| protein profiles of dense-centered forms of five chlamydial strains of animal origin. | purified dense-centered form of 1 bovine strain (lw613) and 3 ovine strains (b577, 034-eye, and 047-eye) of chlamydia psittaci and 1 murine strain of chlamydia trachomatis (mopn) were dissociated in the presence of sodium dodecyl sulfate (sds) and 2-mercaptoethanol. the number of polypeptides detected in the 5 strains varied between 17 and 20, with a molecular weight range of 29,000 to 120,000. two polypeptides predominated and comprised approximately a third of the total protein in each of the ... | 1975 | 1147351 |
| effect of gamma interferon on resolution of murine chlamydial genital infection. | mice infected in the genital tract with the chlamydia trachomatis agent of mouse pneumonitis were treated with monoclonal rat anti-gamma interferon (anti-ifn-gamma) antibody to determine whether ifn-gamma participated in the resolution of the infection. in two experiments, anti-ifn-gamma antibody treatment resulted in significantly prolonged infections. in support of these data, passive administration of recombinant ifn-gamma to chronically infected nu/nu mice was able to bring about resolution ... | 1992 | 1398955 |
| production of colony-stimulating factors during pneumonia caused by chlamydia trachomatis. | the colony-stimulating factors (csfs) are cytokines involved in the production, differentiation, and activation of host phagocytes. during murine infection with chlamydia trachomatis (mopn), plasma csf levels increased in euthymic (nu/+) and athymic (nu/nu) balb/c mice. levels declined later in infection, with the nu/+ mice resolving the infection but the nu/nu mice succumbing by day 16. either live or heat-killed chlamydia organisms could induce csf increases on day 7 postchallenge in nu/+ mice ... | 1991 | 1828791 |
| humoral immune response to chlamydial genital infection of mice with the agent of mouse pneumonitis. | the objective of this study was to characterize the humoral immune response to chlamydial genital infection of mice with the mouse pneumonitis agent (mopn). with an enzyme-linked immunoabsorbent assay, immunoglobulin g antibodies to mopn were first detected in plasma by day 14. peak plasma antibody concentrations were reached by day 49, and this response did not decline significantly throughout the 300-day monitoring period. immunoglobulin a against mopn could first be detected in pooled vaginal ... | 1989 | 2744854 |
| chlamydia trachomatis pneumonia in the immune, athymic and normal balb mouse. | this paper compares the histopathology of pneumonia due to murine chlamydia trachomatis (mopn, mouse pneumonitis agent) in susceptible athymic nude mice (nu/nu), resistant heterozygous littermates (nu/+) and very resistant immunized nu/+ mice. while all groups had an early heterophil response, successful host defence correlated with the presence of large numbers of plasma cells, lymphocytes, monocytes, and lipid laden macrophages. reticulate bodies were seen in all groups, predominantly in type ... | 1987 | 3040067 |
| antibody-mediated modulation of arthritis induced by chlamydia. | the purpose of this investigation was to determine the role of the humoral immune response in the production of arthritis in mice immunized with the chlamydial agent of mouse pneumonitis (mopn) (chlamydia trachomatis biovar). mice were made b cell deficient (bcd) by treatment with rabbit antiserum to murine igm. control mice included animals treated similarly with normal rabbit serum or phosphate-buffered saline. male mice were immunized with mopn inactivated with ultraviolet irradiation while f ... | 1988 | 3400779 |
| chronic chlamydial genital infection in congenitally athymic nude mice. | congenitally athymic nude mice and their heterozygous counterparts were inoculated intravaginally with the chlamydial agent of mouse pneumonitis, a chlamydia trachomatis biovar. heterozygous mice resolved their infections in 20 days, whereas nude mice developed chronic infections which lasted at least 265 days and did not resolve within the time course of the experiments. heterozygous mice produced high levels of antibody in both serum and secretions in contrast to nude mice, which produced very ... | 1985 | 3997251 |
| the role of antibody in host defense against the agent of mouse pneumonitis. | athymic nude (nu/nu) mice, which are more susceptible to the agent of mouse pneumonitis (mopn) (murine chlamydia trachomatis) than are their heterozygous littermates (nu/+), do not develop significant igg or iga antibody to the mopn agent. nu/+ mice develop significant titers of both specific igg or iga antibodies after either intranasal or intrauterine challenge. prior intranasal or intrauterine immunization protects nu/+ but not nu/nu mice against subsequent intranasal challenge with the mopn ... | 1982 | 7054323 |
| a new animal model for the study of chlamydia trachomatis genital infections: infection of mice with the agent of mouse pneumonitis. | a new animal model for the study of genital infections caused by chlamydia trachomatis has been developed. female mice were successfully infected after intravaginal inoculation with the c. trachomatis agent of mouse pneumonitis. evidence for infection was obtained by detection of chlamydial inclusions in smears of cervical scrapings treated with giemsa stain. chlamydiae were observed in sections of cervical tissues examined by light and electron microscopy as well as by immunofluorescence micros ... | 1981 | 7217713 |
| pneumonia due to chlamydia trachomatis in the immunocompromised (nude) mouse. | athymic nude mice (nu/nu) were significantly more susceptible to pneumonia due to the agent of mouse pneumonitis (mopn), chlamydia trachomatis, than their heterozygous (nu/+) littermates, as judged both by a greater mortality and a decreased ability to rid their lungs of the infection. nu/nu mice did not produce significant antibody to the mopn agent, whereas nu/+ mice did. thymic transplantation rendered nu/nu mice significantly more resistant to the mopn agent than nu/nu controls. resistance t ... | 1981 | 7217718 |
| protective efficacy of major outer membrane protein-specific immunoglobulin a (iga) and igg monoclonal antibodies in a murine model of chlamydia trachomatis genital tract infection. | the protective efficacy of immunoglobulin a (iga) and igg monoclonal antibodies (mabs) specific for the major outer membrane protein of chlamydia trachomatis mopn was evaluated in a murine genital tract infection model. mabs were delivered into serum and vaginal secretions of naive mice by using the backpack hybridoma tumor system, and protective efficacy was assessed over the first 8 days following challenge by quantitative determination of chlamydial recovery from cervicovaginal swabs, histopa ... | 1995 | 7591126 |
| local th1-like responses are induced by intravaginal infection of mice with the mouse pneumonitis biovar of chlamydia trachomatis. | a critical role for cell-mediated immunity (cmi) has been demonstrated for effecting the resolution of genital infections of mice infected intravaginally with the mouse pneumonitis biovar of chlamydia trachomatis (mopn). however, little is known about expression of cmi in the murine genital tract. the mouse mopn model was used to examine cmi responses in the genital tract and associated lymph nodes during the course of infection. mopn-specific lymphocytes were present in the genital mucosa, with ... | 1995 | 7729886 |
| effect of gamma-irradiation on the effector function of t lymphocytes in microbial control. | a chlamydial-specific t cell clone, capable of inhibiting the growth of infectious chlamydia in vivo and in vitro, was employed to investigate the effect of gamma-irradiation on the ability of effector t cells to control infections. clone 2.14-0 (cd4+), specific for the chlamydia trachomatis biovar agent of mouse pneumonitis (mopn), was irradiated with varying doses (0, 2.5, 5.0, 10.0, 20.0 and 40.0 gy) and its biological functions and ability to inhibit the intraepithelial growth of mopn were a ... | 1995 | 7775831 |
| characteristics of murine model of genital infection with chlamydia trachomatis and effects of therapy with tetracyclines, amoxicillin-clavulanic acid, or azithromycin. | following intravaginal inoculation of progesterone-treated outbred mice with chlamydia trachomatis mopn, 4 to 6 log10 inclusion-forming units were recovered in vaginal swabs for 21 days but all animals were culture negative after 28 days. serum antibody titers were elevated and remained high for at least 70 days. between 28 and 70 days, upper tract infection (inflammation and distension of the uterine horns, occlusion of oviducts with inflammatory exudate, pyosalpinx, and hydrosalpinx) was seen ... | 1994 | 7811001 |
| role for cd8+ t cells in antichlamydial immunity defined by chlamydia-specific t-lymphocyte clones. | the role of cd8+ t cells in antichlamydial immunity was investigated in a murine model of chlamydial genital infection by using t-cell clones generated against the chlamydia trachomatis agent of mouse pneumonitis (mopn). two cd8+ t-cell clones tested (2.1f and 2.14-9) were chlamydia antigen specific and mhc restricted and reacted against mopn as well as the chlamydia psittaci agent of guinea pig inclusion conjunctivitis and c. trachomatis serovar e, suggesting the recognition of a genus-specific ... | 1994 | 7927806 |
| an in vitro model for immune control of chlamydial growth in polarized epithelial cells. | a polarized epithelial culture system and chlamydia-specific t-cell lines and clones were employed to investigate the ability and mechanisms by which t cells control the growth of chlamydiae in epithelial cells. monolayers of polarized mouse epithelial cells were infected with the chlamydia trachomatis agent of mouse pneumonitis (mopn) and then exposed to antigen-stimulated mopn-specific t-cell lines and clones. the results revealed that in vivo-protective mopn-specific t-cell lines and clone 2. ... | 1994 | 8039923 |
| resolution of murine chlamydial genital infection by the adoptive transfer of a biovar-specific, th1 lymphocyte clone. | mopn-specific t-cell clones were isolated from a t-cell line that was capable of curing chlamydial genital infection by the chlamydia trachomatis agent of mouse pneumonitis (mopn) after adoptive transfer. two clones (designated as 2.14-0 and 2.14-3) were characterized by flow cytometry techniques to be homogenous for l3t4, cd3, and alpha/beta t cell receptor (tcr) t-helper cell markers. the two clones were biovar specific, because they reacted to mopn but not the chlamydia psittaci agent of guin ... | 1993 | 8068534 |
| integrin-mediated epithelial-t cell interaction enhances nitric oxide production and increased intracellular inhibition of chlamydia. | t cell-mediated immunity against chlamydia in mice is mediated at least in part by t cell-derived interferon-gamma (ifn-gamma) induction of the nitric oxide synthase (inos) system in infected epithelial cells. although ifn-gamma alone could stimulate nitric oxide (no) production from epithelial cells and inhibit the intracellular growth of chlamydia, the effectiveness was less than when infected epithelial cells were co-cultured with ifn-gamma-producing t cell clones. in co-cultures containing t ... | 1996 | 8656050 |
| the molecular mechanism of t-cell control of chlamydia in mice: role of nitric oxide. | t-cell mediated immunity (cmi) is crucial for protection against genital chlamydial infection in mice. to define the underlying molecular mechanism for this protection, several t-cell clones generated against the chlamydia trachomatis agent of mouse pneumonitis (mopn) were analysed in an in vitro model of the mucosal epithelium, the polarized epithelial-lymphocyte co-culture (pelc) system, for immunobiological functions that correlated with chlamydial inhibition. the six clones analysed were cla ... | 1996 | 8666420 |
| molecular mechanism of t-cell control of chlamydia in mice: role of nitric oxide in vivo. | t-cell-mediated immunity is crucial for the control of chlamydia in mice. recent evidence from studies in an in vitro model of the mucosal epithelium, the polarized epithelial-lymphocyte co-culture (pelc) system, indicated that protective murine t cells mediated intracellular inhibition of the chlamydia trachomatis agent of mouse pneumonitis (mopn) at least partly by activating the interferon-gamma (ifn-gamma)-inducible nitric oxide synthase (inos) pathway. to investigate whether nitric oxide pl ... | 1996 | 8707333 |
| initial route of antigen administration alters the t-cell cytokine profile produced in response to the mouse pneumonitis biovar of chlamydia trachomatis following genital infection. | a th1-type response develops following vaginal infection with the mouse pneumonitis biovar of chlamydia trachomatis (mopn). since the type of response, i.e., th1 versus th2, can be influenced by factors present during t-cell activation, we examined the effects of different routes of mopn administration on the cytokine profile and resistance against infection following a mopn vaginal challenge. a dominant th1-type cytokine profile developed in mice given live mopn via the intranasal, oral, and va ... | 1996 | 8945535 |
| does chlamydia trachomatis mopn enter a microbiologically-inapparent state during experimental infection of the mouse genital tract? | microbiologically-inapparent chlamydial infection may contribute towards the immunopathogenesis of these diseases. although morphologically and physiologically aberrant non-cultivable chlamydiae can be induced reversibly in cell culture, evidence for these forms in infections of animals and humans is indirect. a mouse model of salpingitis caused by the mouse pneumonitis biovar of chlamydia trachomatis (mopn) was used to determine the existence of non-cultivable organisms in vivo. following intra ... | 1997 | 9049999 |
| reactivation of chlamydial genital tract infection in mice. | a model was developed to study chlamydial quiescence in c3h/hen (c3h) and c57bl/6n (c57) mice following genital tract infection by chlamydia trachomatis mopn. reactivation of chlamydial shedding following immunosuppression indicated that viable mopn remained in the genital tract for up to 4 or 5 weeks after the apparent clearance of a primary infection. either cyclophosphamide or cortisone acetate treatment could cause reactivation, but cyclophosphamide was more effective. however, the frequency ... | 1997 | 9169733 |
| dissemination of chlamydia trachomatis chronic genital tract infection in gamma interferon gene knockout mice. | mice (c57bl/6), treated with progesterone and infected intravaginally with the mouse pneumonitis strain of chlamydia trachomatis (mopn), acquired genital tract disease that ascended from the endocervix to the uterine horns, oviducts, and ovaries in a temporal fashion before the occurrence of spontaneous microbiological resolution by about 28 days after infection. surprisingly, dissemination of mopn in small numbers to draining lymph nodes, the peritoneal cavity, spleen, liver, kidneys, and lungs ... | 1997 | 9169744 |
| identification of homing receptors that mediate the recruitment of cd4 t cells to the genital tract following intravaginal infection with chlamydia trachomatis. | murine genital infection induced with the mouse pneumonitis biovar of chlamydia trachomatis (mopn) elicits a short-lived protective immunity mediated primarily by th1 cd4 cells. to understand the development of local cell-mediated immunity against c. trachomatis infection, we investigated the mechanism(s) which mediates cd4 lymphocyte migration to the genital mucosa by identifying molecules that could support this process. we found that primarily cd4 cells were recruited to the genital tract (gt ... | 1997 | 9393816 |
| role of nk cells in early host response to chlamydial genital infection. | the cell-mediated immune response has been documented to be the major protective immune mechanism in mice infected genitally with the agent of mouse pneumonitis (mopn), a biovar of chlamydia trachomatis. moreover, there is strong evidence to indicate that gamma interferon (ifn-gamma) is a major effector mechanism of the cell-mediated immune response. previous studies from this laboratory have also reported that the dominant cell population in the genital tract is the cd4 th1 population. when exp ... | 1998 | 9826367 |
| emended description of the order chlamydiales, proposal of parachlamydiaceae fam. nov. and simkaniaceae fam. nov., each containing one monotypic genus, revised taxonomy of the family chlamydiaceae, including a new genus and five new species, and standards for the identification of organisms. | the current taxonomic classification of chlamydia is based on limited phenotypic, morphologic and genetic criteria. this classification does not take into account recent analysis of the ribosomal operon or recently identified obligately intracellular organisms that have a chlamydia-like developmental cycle of replication. neither does it provide a systematic rationale for identifying new strains. in this study, phylogenetic analyses of the 16s and 23s rrna genes are presented with corroborating ... | 1999 | 10319462 |
| differential regulation of cd4 lymphocyte recruitment between the upper and lower regions of the genital tract during chlamydia trachomatis infection. | genital infection with chlamydia trachomatis results in both the local recruitment of protective immune responses and an inflammatory infiltrate that may also participate in tubal pathology. as a beginning to understanding the etiology of immune system-mediated tubal pathology, we evaluated the regional recruitment of lymphocyte subsets to different areas of the female genital tract (gt) over the course of a murine infection with the mouse pneumonitis agent of chlamydia trachomatis (mopn). using ... | 2000 | 10678969 |
| genome sequences of chlamydia trachomatis mopn and chlamydia pneumoniae ar39. | the genome sequences of chlamydia trachomatis mouse pneumonitis (mopn) strain nigg (1 069 412 nt) and chlamydia pneumoniae strain ar39 (1 229 853 nt) were determined using a random shotgun strategy. the mopn genome exhibited a general conservation of gene order and content with the previously sequenced c.trachomatis serovar d. differences between c.trachomatis strains were focused on an approximately 50 kb 'plasticity zone' near the termination origins. in this region mopn contained three copies ... | 2000 | 10684935 |
| characterization of the rnpb gene and rnase p rna in the order chlamydiales. | the sequence of the rnase p rna gene (rnpb) was determined for 60 strains representing all nine species in the family chlamydiaceae and for the related chlamydiales species, parachlamydia acanthamoebae and simkania negevensis. these sequences were used to infer evolutionary relationships among the chlamydiaceae. the analysis separated chlamydophila and chlamydia into two lineages, with chlamydophila forming three distinct clusters: the chlamydophila pneumoniae strains; the chlamydophila pecorum ... | 2000 | 10826799 |
| mouse strain-dependent chemokine regulation of the genital tract t helper cell type 1 immune response. | vaginal infection with the mouse pneumonitis agent of chlamydia trachomatis (mopn) produces shorter courses of infection in c57bl/6 and balb/c mice than in c3h/hen mice, while c57bl/6 mice are more resistant to oviduct pathology. a robust th1 response is extremely important in host defense against chlamydia. in this study we examined gamma interferon (ifn-gamma), interleukin 10 (il-10), and the t-cell-regulatory chemokines macrophage inflammatory protein-1alpha (mip-1alpha) and monocyte chemoatt ... | 2001 | 11705916 |
| chemokine and chemokine receptor dynamics during genital chlamydial infection. | current design strategies for vaccines against certain microbial pathogens, including chlamydia trachomatis, require the induction and targeting of specific immune effectors to the local sites of infection known as the mucosal effector sites. chemokines and their receptors are important mediators of leukocyte trafficking and of the controlled recruitment of specific leukocyte clonotypes during host defense against infections and during inflammation. we analyzed the dynamics of chemokine and chem ... | 2002 | 11796619 |
| inhibition of apoptosis by gamma interferon in cells and mice infected with chlamydia muridarum (the mouse pneumonitis strain of chlamydia trachomatis). | the effect of gamma interferon (ifn-gamma) on apoptosis due to infection by chlamydia muridarum (the mouse pneumonitis strain of chlamydia trachomatis) was studied in epithelial cells in culture and in the genital tracts of mice. ifn-gamma concentrations that induce the formation of aberrant, persistent chlamydiae inhibit apoptosis due to c. muridarum infection. in cells treated with an ifn-gamma concentration that leads to the development of a heterogenous population of normal and aberrant chla ... | 2002 | 11953396 |
| a chlamydia trachomatis-specific th2 clone does not provide protection against a genital infection and displays reduced trafficking to the infected genital mucosa. | a t helper type 1 (th1) response is essential for resolving genital infections with the mouse pneumonitis biovar of chlamydia trachomatis (mopn). however, t-cell-dependent anti-chlamydial antibody is produced and may also contribute to protective immunity. we produced a mopn-specific cd4 th2 clone (th2-mopn) to study the role of a th2 response during infection. we found that th2-mopn was unable to eradicate chlamydiae from the genital tract (gt) when it was transferred into mopn-infected nude mi ... | 2002 | 12183563 |
| a new family of highly variable proteins in the chlamydophila pneumoniae genome. | chlamydiaceae are obligate intracellular bacterial pathogens characterized by a wide range of vertebrate host, tissue tropism and spectrum of diseases. to get insights into the biological mechanisms involved in these differences, we have put forward a computational and experimental procedure to identify the genome recombination hotspots, as frequent sequence variation allows rapid adaptation to environmental changes. we find a larger potential for recombination in chlamydophila pneumoniae genome ... | 2002 | 12384581 |
| role of proapoptotic bax in propagation of chlamydia muridarum (the mouse pneumonitis strain of chlamydia trachomatis) and the host inflammatory response. | the bcl-2 family member bax plays a critical role in regulating apoptosis. surprisingly, bax-deficient mice display limited phenotypic abnormalities. here we investigate the effect of bax on infection by the sexually transmitted pathogen, chlamydia muridarum (the mouse pneumonitis strain of chlamydia trachomatis). bax(-/-) cells are relatively resistant to chlamydia-induced apoptosis, and fewer bacteria are recovered after two infection cycles from bax(-/-) cells than from wild-type cells. these ... | 2003 | 12509420 |
| genome sequence of chlamydophila caviae (chlamydia psittaci gpic): examining the role of niche-specific genes in the evolution of the chlamydiaceae. | the genome of chlamydophila caviae (formerly chlamydia psittaci, gpic isolate) (1 173 390 nt with a plasmid of 7966 nt) was determined, representing the fourth species with a complete genome sequence from the chlamydiaceae family of obligate intracellular bacterial pathogens. of 1009 annotated genes, 798 were conserved in all three other completed chlamydiaceae genomes. the c.caviae genome contains 68 genes that lack orthologs in any other completed chlamydial genomes, including tryptophan and t ... | 2003 | 12682364 |
| inhibition of the growth of agents of the psittacosis group by d-cycloserine and its specific reversal by d-alanine. | moulder, james w. (university of chicago, chicago, ill.), dorothy l. novosel, and julius e. officer. inhibition of the growth of agents of the psittacosis group by d-cycloserine and its specific reversal by d-alanine. j. bacteriol. 85:707-711. 1963.-d-cycloserine inhibited multiplication of four members of the psittacosis group in chick embryo yolk sac. d-alanine reversed each inhibition. in infections with the agent of mouse pneumonitis, the most sensitive member of the psittacosis group tested ... | 1963 | 14042952 |
| rab gtpases are recruited to chlamydial inclusions in both a species-dependent and species-independent manner. | chlamydiae are obligate intracellular bacteria that replicate within an inclusion that is trafficked to the peri-golgi region where it fuses with exocytic vesicles. the host and chlamydial proteins that regulate the trafficking of the inclusion have not been identified. since rab gtpases are key regulators of membrane trafficking, we examined the intracellular localization of several green fluorescent protein (gfp)-tagged rab gtpases in chlamydia-infected hela cells. gfp-rab4 and gfp-rab11, whic ... | 2003 | 14500507 |
| transcutaneous immunization with combined cholera toxin and cpg adjuvant protects against chlamydia muridarum genital tract infection. | chlamydia trachomatis is a pathogen of the genital tract and ocular epithelium. infection is established by the binding of the metabolically inert elementary body (eb) to epithelial cells. these are taken up by endocytosis into a membrane-bound vesicle termed an inclusion. the inclusion avoids fusion with host lysosomes, and the ebs differentiate into the metabolically active reticulate body (rb), which replicates by binary fission within the protected environment of the inclusion. during the ex ... | 2004 | 14742549 |
| murine oviduct epithelial cell cytokine responses to chlamydia muridarum infection include interleukin-12-p70 secretion. | epithelial cells play an important role in host defense as sentinels for invading microbial pathogens. chlamydia trachomatis is an intracellular bacterial pathogen that replicates in reproductive tract epithelium. epithelial cells lining the reproductive tract likely play a key role in triggering inflammation and adaptive immunity during chlamydia infections. for this report a murine oviduct epithelial cell line was derived in order to determine how epithelial cells influence innate and adaptive ... | 2004 | 15213139 |
| intranasal immunization with c. muridarum major outer membrane protein (momp) and cholera toxin elicits local production of neutralising iga in the prostate. | successful control of sexually transmitted diseases (stds) through vaccination will require the development of vaccine strategies that target protective immunity to both the female and male reproductive tracts (mrt). in the male, the immune privileged nature of the male reproductive tract provides a barrier to entry of serum immunoglobulins into the male reproductive ducts, thereby preventing the induction of protective immunity using conventional injectable vaccination techniques. in this study ... | 2004 | 15474723 |
| the infecting dose of chlamydia muridarum modulates the innate immune response and ascending infection. | murine vaginal infection with the obligate intracellular bacterium chlamydia muridarum is commonly used as a model for ascending chlamydia infections of the human female genital tract. gamma interferon-producing th1 cells, in concert with other mononuclear infiltrates, primarily mediate antichlamydial immunity. however, many factors modify this response, including the bacterial load. to investigate the manner in which the inoculating dose of c. muridarum modulates a genital infection, we measure ... | 2004 | 15501762 |
| histopathologic changes related to fibrotic oviduct occlusion after genital tract infection of mice with chlamydia muridarum. | we sought to determine if intraluminal occluding fibrosis of the oviduct occurs after urogenital chlamydia muridarum infection in mice. | 2005 | 15614121 |
| immunology of chlamydia infection: implications for a chlamydia trachomatis vaccine. | sexually transmitted chlamydia trachomatis infections are a serious public-health problem. with more than 90 million new cases occurring annually, c. trachomatis is the most common cause of bacterial sexually transmitted disease worldwide. recent progress in elucidating the immunobiology of chlamydia muridarum infection of mice has helped to guide the interpretation of immunological findings in studies of human c. trachomatis infection and has led to the development of a common model of immunity ... | 2005 | 15688042 |
| production of a proteolytically active protein, chlamydial protease/proteasome-like activity factor, by five different chlamydia species. | we have previously identified a chlamydial protein, chlamydial protease/proteasome-like activity factor (cpaf), for degrading host transcription factors in cells infected with the human chlamydial species chlamydia trachomatis or chlamydia pneumoniae. we now report that functional cpaf was also produced during infection with the species chlamydia muridarum, chlamydia psittaci, and chlamydia caviae, which primarily infect nonhuman hosts. | 2005 | 15731091 |
| differences in growth characteristics and elementary body associated cytotoxicity between chlamydia trachomatis oculogenital serovars d and h and chlamydia muridarum. | in vitro growth and elementary body (eb) associated cytotoxicity of two chlamydia trachomatis strains belonging to serovars d and h and c muridarum were compared to identify difference(s) that correlate with virulence variations between these strains in the mouse model of human female genital tract infection, and phenotypic characteristics that could explain human epidemiological data on serovar prevalence and levels of shedding during serovar d and h infection. | 2005 | 15790704 |
| tyrosine phosphorylation of the chlamydial effector protein tarp is species specific and not required for recruitment of actin. | chlamydiae are obligate intracellular pathogens that efficiently induce their endocytosis by susceptible eukaryotic host cells. recently, a chlamydia trachomatis type iii secreted effector protein, tarp, was found to be translocated and tyrosine phosphorylated at the site of entry and associated with the recruitment of actin that coincides with endocytosis. c. trachomatis tarp possesses up to six direct repeats of approximately 50 amino acids each. the majority of the tyrosine residues are found ... | 2005 | 15972471 |
| cationic liposomes containing mycobacterial lipids: a new powerful th1 adjuvant system. | the immunostimulation provided by the mycobacterial cell wall has been exploited for many decades, e.g., in freund's complete adjuvant. recently, the underlying mechanism behind this adjuvant activity, including toll receptor signaling, has begun to be unraveled, confirming the potential of mycobacterial constituents to act as adjuvants. in this study, the immunostimulatory properties of a mycobacterium bovis bcg lipid extract were tested for their adjuvant activity. administration of the lipids ... | 2005 | 16113300 |
| comparison of intranasal and transcutaneous immunization for induction of protective immunity against chlamydia muridarum respiratory tract infection. | chlamydia pneumoniae causes a range of respiratory infections including bronchitis, pharyngitis and pneumonia. infection has also been implicated in exacerbation/initiation of asthma and chronic obstructive pulmonary disease (copd) and may play a role in atherosclerosis and alzheimer's disease. we have used a mouse model of chlamydia respiratory infection to determine the effectiveness of intranasal (in) and transcutaneous immunization (tci) to prevent chlamydia lung infection. female balb/c mic ... | 2006 | 16153755 |
| expression of matrix metalloproteinases subsequent to urogenital chlamydia muridarum infection of mice. | the central hypothesis of this study was that matrix metalloproteinases (mmps) would be enhanced following murine chlamydial infection and that their expression would vary in mouse strains that differ in their susceptibility to chronic chlamydia-induced disease. to address this hypothesis, female c3h/hen and c57bl/6 mice were infected intravaginally with chlamydia muridarum. uterine and oviduct tissues were assessed for transcription of mmp genes and their tissue inhibitors. an increased activit ... | 2005 | 16177376 |
| pattern recognition molecules activated by chlamydia muridarum infection of cloned murine oviduct epithelial cell lines. | chlamydia trachomatis is the most common bacterial sexually transmitted disease in the united states and a major cause of female infertility due to infection-induced fallopian tube scarring. epithelial cells are likely central to host defense and pathophysiology as they are the principal cell type productively infected by c. trachomatis. we generated cloned murine oviduct epithelial cell lines without viral or chemical transformation to investigate the role of the tlrs and cytosolic nucleotide b ... | 2005 | 16237102 |
| cox-2 inhibition affects growth rate of chlamydia muridarum within epithelial cells. | chlamydiae alter apoptosis of host target cells, which regulates their growth. cyclooxygenase-2 (cox-2), the rate-limiting enzyme for prostaglandin e2 (pge2) production, modulates epithelial cell survival. we addressed whether endogenous pge2 alters chlamydial growth or apoptosis of epithelial cells infected with chlamydia muridarum. pge2 is secreted by infected host cells in the genital tract (gt). using immunohistochemical techniques, we found that cox-2 enzyme was localized to epithelial cell ... | 2006 | 16297651 |
| a new mouse model of chlamydia trachomatis mopn genital infection. | | 1989 | 16312297 |
| comparison of gamma interferon-mediated antichlamydial defense mechanisms in human and mouse cells. | gamma interferon (ifn-gamma)-induced effector mechanisms have potent antichlamydial activities that are critical to host defense. the most prominent and well-studied effectors are indoleamine dioxygenase (ido) and nitric oxide (no) synthase. the relative contributions of these mechanisms as inhibitors of chlamydial in vitro growth have been extensively studied using different host cells, induction mechanisms, and chlamydial strains with conflicting results. here, we have undertaken a comparative ... | 2006 | 16368976 |
| stimulation of the cytosolic receptor for peptidoglycan, nod1, by infection with chlamydia trachomatis or chlamydia muridarum. | infection of epithelial cells by the intracellular pathogen, chlamydia trachomatis, leads to activation of nf-kappab and secretion of pro-inflammatory cytokines. we find that overexpression of a dominant-negative nod1 or depletion of nod1 by rna interference inhibits partially the activation of nf-kappab during chlamydial infection in vitro, suggesting that nod1 can detect the presence of chlamydia. in parallel, there is a larger increase in the expression of pro-inflammatory genes following chl ... | 2006 | 16681844 |
| recruitment of bad by the chlamydia trachomatis vacuole correlates with host-cell survival. | chlamydiae replicate intracellularly in a vacuole called an inclusion. chlamydial-infected host cells are protected from mitochondrion-dependent apoptosis, partly due to degradation of bh3-only proteins. the host-cell adapter protein 14-3-3beta can interact with host-cell apoptotic signaling pathways in a phosphorylation-dependent manner. in chlamydia trachomatis-infected cells, 14-3-3beta co-localizes to the inclusion via direct interaction with a c. trachomatis-encoded inclusion membrane prote ... | 2006 | 16710454 |
| a plasmid-cured chlamydia muridarum strain displays altered plaque morphology and reduced infectivity in cell culture. | a highly conserved cryptic plasmid is present in chlamydia trachomatis yet naturally occurring plasmid-deficient isolates are very rare. this paper describes the isolation and characterization of a plasmid-deficient strain of c. muridarum, using novobiocin as a curing agent. plasmid-deficient derivatives of c. muridarum strain nigg were generated at high efficiencies (4-30%). phenotypic characterization revealed that the cured derivative was unable to accumulate glycogen within intracytoplasmic ... | 2006 | 16735724 |
| susceptibility of prostate epithelial cells to chlamydia muridarum infection and their role in innate immunity by recruitment of intracellular toll-like receptors 4 and 2 and myd88 to the inclusion. | although chlamydia infections are widespread throughout the world, data about immunopathogenesis of genitourinary tract infections in males are very limited. in the present work we present an in vitro model of male genital tract-derived epithelial cells, more precisely prostate epithelial cells (pec), to analyze if they are susceptible and able to respond to chlamydia muridarum infection. our results demonstrate that rat pec are susceptible to c. muridarum infection and respond to this pathogen ... | 2006 | 16954392 |
| inhibition of matrix metalloproteinases protects mice from ascending infection and chronic disease manifestations resulting from urogenital chlamydia muridarum infection. | matrix metalloproteinases (mmp) are a family of host-derived enzymes involved in the turnover of extracellular matrix molecules. we have previously reported enhanced expression of matrix metalloproteinases in chlamydia muridarum urogenital tract infection of female mice. kinetics and patterns of mmp expression as well as enhanced expression in susceptible strains of mice in the prior study implied a role for mmp in pathogenesis. to explore this further, we infected a susceptible strain of mice ( ... | 2006 | 16988226 |
| outcome of urogenital infection with chlamydia muridarum in cd14 gene knockout mice. | cd14 has been postulated to play a role in chlamydial immunity and immunopathology. there is evidence to support this role in human infections but its function in a mouse model has not been investigated. | 2006 | 16995947 |
| chlamydial protease-like activity factor induces protective immunity against genital chlamydial infection in transgenic mice that express the human hla-dr4 allele. | there is no licensed vaccine available against chlamydia trachomatis, the leading cause of bacterial sexually transmitted disease. we have found that intranasal immunization with recombinant chlamydial protease-like activity factor (cpaf) induces cd4(+) t-cell- and gamma interferon (ifn-gamma)-dependent protective immunity against murine genital chlamydial infection, thus making cpaf a viable vaccine candidate for further characterization. hla-dr4 is the predominant allele involved in chlamydial ... | 2006 | 17015458 |
| novel overlapping coding sequences in chlamydia trachomatis. | chlamydia trachomatis is the aetiological agent of trachoma and sexually transmitted infections. the c. trachomatis genome sequence revealed an organism adapted to the intracellular habitat with a high coding ratio and a small genome consisting of 1.042-kilobase (kb) with 895 annotated protein coding genes. here, we repredict the protein-coding genes of the c. trachomatis genome using the gene-finder easygene that was trained specifically for c. trachomatis, and compare it with the primary c. tr ... | 2006 | 17038047 |
| genetic profiling of dendritic cells exposed to live- or ultraviolet-irradiated chlamydia muridarum reveals marked differences in cxc chemokine profiles. | chlamydia trachomatis is a major cause of sexually transmitted disease worldwide for which an effective vaccine is being actively pursued. current vaccine efforts will be aided by elucidating the interaction between chlamydia and dendritic cells (dcs). protective immunity appears to develop slowly following natural infection in humans, and early vaccine trials using inactivated c. trachomatis resulted in partial, short-lived protection with possible enhanced inflammatory pathology during re-infe ... | 2007 | 17073942 |
| adoptive transfer of cd8alpha+ dendritic cells (dc) isolated from mice infected with chlamydia muridarum are more potent in inducing protective immunity than cd8alpha- dc. | chlamydial infections are serious public health concerns worldwide. in this study, we examined the role of dendritic cell (dc) subsets in inducing protective immunity against chlamydial infection using an adoptive transfer approach. we found that cd11c+cd8alpha+ (double-positive, dp) dc, compared with cd11c+cd8alpha- (single-positive, sp) dc isolated from infected mice, are more potent inducers of protective immunity. specifically, mice pretreated with dpdc from infected mice, upon infection wit ... | 2006 | 17082623 |
| the protective efficacy of chlamydial protease-like activity factor vaccination is dependent upon cd4+ t cells. | we have previously determined the protective efficacy of intranasal vaccination with chlamydial protease-like activity factor (cpaf) against genital chlamydial infection. since t-helper 1 (th1) responses are important for anti-chlamydial immunity, we examined the contribution of cd4(+) t cells in cpaf mediated immunity against intravaginal (i.vag.) chlamydia muridarum infection in c57bl/6 mice. cpaf+il-12 vaccination induced antigen-specific cd4(+) t cells that secreted elevated levels of ifn-ga ... | 2006 | 17116296 |
| intranasal vaccination with a secreted chlamydial protein enhances resolution of genital chlamydia muridarum infection, protects against oviduct pathology, and is highly dependent upon endogenous gamma interferon production. | there is currently no licensed vaccine against chlamydia trachomatis, the leading cause of sexually transmitted bacterial disease worldwide. conventional vaccination attempts using surface-exposed chlamydial antigens have achieved only partial success. we have employed a novel vaccination strategy using a secreted protein, chlamydial protease-like activity factor (cpaf), which has been shown to degrade host major histocompatibility complex transcription factors and keratin-8 and therefore may al ... | 2007 | 17118987 |
| chlamydia muridarum infection elicits a beta interferon response in murine oviduct epithelial cells dependent on interferon regulatory factor 3 and trif. | chlamydia trachomatis is the most common sexually transmitted bacterial infection in the united states. utilizing cloned murine oviduct epithelial cell lines, we previously identified toll-like receptor 2 (tlr2) as the principal epithelial pattern recognition receptor (prr) for infection-triggered release of the acute inflammatory cytokines interleukin-6 and granulocyte-macrophage colony-stimulating factor. the infected oviduct epithelial cell lines also secreted the immunomodulatory cytokine be ... | 2007 | 17178782 |
| distinct nkt cell subsets are induced by different chlamydia species leading to differential adaptive immunity and host resistance to the infections. | we investigated the role of nkt cells in immunity to chlamydia pneumoniae and chlamydia muridarum infections using a combination of knockout mice and specific cellular activation approaches. the nkt-deficient mice showed exacerbated susceptibility to c. pneumoniae infection, but more resistance to c. muridarum infection. activation of nkt reduced c. pneumoniae in vivo growth, but enhanced c. muridarum infection. cellular analysis of invariant nkt cells revealed distinct cytokine patterns followi ... | 2007 | 17202368 |
| chlamydial interferon gamma immune evasion influences infection tropism. | chlamydia trachomatis is a human pathogen and chlamydia muridarum is a mouse pathogen but paradoxically, they share near genomic synteny. the majority of strain-variable genes are located primarily in a hyper-variable region termed the plasticity zone. tryptophan synthase and cytotoxin are plasticity zone genes unique to the human and murine strains, respectively. tryptophan synthase is a virulence factor that differentiates c. trachomatis strains into genital and ocular disease pathotypes, wher ... | 2007 | 17208039 |
| expression library immunization confers partial protection against chlamydia muridarum genital infection. | protective sequences of chlamydia muridarum were identified as potential vaccine candidates by screening a genomic dna expression library and assessing the immune responses of mice immunized with individual library clones following vaginal challenge with live chlamydia. groups of female balb/c mice were immunized intra-abdominally by gene gun delivery of dna three times at three-weekly intervals with individual library clones expressing chlamydial protein fragments and humoral and cell-mediated ... | 2007 | 17239501 |
| intranasal immunization with chlamydial protease-like activity factor and cpg deoxynucleotides enhances protective immunity against genital chlamydia muridarum infection. | we have reported recently that intranasal (i.n.) vaccination with chlamydial protease-like activity factor (cpaf) and interleukin-12 (il-12) enhances protective immunity against genital chlamydial challenge. in this study, we show that i.n. or intraperitoneal (i.p.) vaccination with cpaf plus cpg deoxynucleotides (cpg), an alternative t helper 1 (th1) adjuvant, induced robust cpaf-specific ifn-gamma responses and elevated levels of serum antibody and vaginal iga production. cpaf+cpg vaccinated a ... | 2007 | 17349723 |
| phenotypic rescue of chlamydia trachomatis growth in ifn-gamma treated mouse cells by irradiated chlamydia muridarum. | chlamydia trachomatis and c. muridarum, human and mouse pathogens, respectively, share more than 99% of open reading frames (orfs) but differ in a cytotoxin locus. presence or absence of cytotoxin gene(s) in these strains correlates with their ability to grow in ifn-gamma treated mouse cells. growth of toxin-positive c. muridarum is not affected in ifn-gamma treated cells, whereas growth of toxin-negative c. trachomatis is inhibited. we previously reported that this difference in ifn-gamma sensi ... | 2007 | 17501981 |
| survival of chlamydia muridarum within dendritic cells. | immune responses to chlamydia trachomatis underlay both immunity and immunopathology. immunopathology in turn has been attributed to chronic persistent infection with persistence being defined as the presence of organisms in the absence of replication. we hypothesized that dendritic cells (dcs) play a central role in chlamydia immunity and immunopathology by favoring the long-term survival of c. muridarum. this hypothesis was examined based on (i) direct staining of chlamydia in infected dcs to ... | 2007 | 17502393 |
| epithelial membrane protein 2 modulates infectivity of chlamydia muridarum (mopn). | chlamydiae are bacterial pathogens which have evolved efficient strategies to enter, replicate, and survive inside host epithelial cells, resulting in acute and chronic diseases in humans and other animals. several candidate molecules in the host receptor complex have been identified, but the precise mechanisms of infection have not been elucidated. epithelial membrane protein-2 (emp2), a 4-transmembrane protein, is highly expressed in epithelial cells in sites of chlamydial infections. here we ... | 2007 | 17544801 |
| prostaglandin e2 modulates dendritic cell function during chlamydial genital infection. | inflammatory responses mediated by antigen-presenting dendritic cells (dcs), can be modulated by the presence of prostaglandins (pg), including prostaglandin e2 (pge2). pge2 modifies the production of an immune response by altering dc function through pge2 receptors. pge2 is produced by epithelial cells lining the murine female reproductive tract during chlamydia muridarum infection and likely manipulates the antichlamydial immune response during antigen uptake in the genital mucosa. our data de ... | 2008 | 17680801 |
| plasmid-deficient chlamydia muridarum fail to induce immune pathology and protect against oviduct disease. | chlamydia trachomatis is the most prevalent sexually transmitted bacterial infection in the world. in women, genital infection can cause endometritis and pelvic inflammatory disease with the severe sequelae of ectopic pregnancy or infertility. chlamydia sp. do not damage tissues directly, but induce an injurious host inflammatory response at the infected site. in the murine model of genital disease with chlamydia muridarum, tlr2 plays a role in both early production of inflammatory mediators and ... | 2007 | 17785841 |
| separate base usages of genes located on the leading and lagging strands in chlamydia muridarum revealed by the z curve method. | the nucleotide compositional asymmetry between the leading and lagging strands in bacterial genomes has been the subject of intensive study in the past few years. it is interesting to mention that almost all bacterial genomes exhibit the same kind of base asymmetry. this work aims to investigate the strand biases in chlamydia muridarum genome and show the potential of the z curve method for quantitatively differentiating genes on the leading and lagging strands. | 2007 | 17925038 |
| induction of cross-serovar protection against genital chlamydial infection by a targeted multisubunit vaccination approach. | an important consideration for antichlamydial vaccine development is the induction of cross-serovar protection, since multiple serovars (d to l) of chlamydia trachomatis cause genital infections. we have shown previously that vaccination with c. trachomatis-derived recombinant chlamydial protease-like activity factor (rcpaf) induced significant earlier resolution of chlamydia muridarum infection and reduced oviduct pathology. however, the vaccinated mice continued to shed chlamydiae for up to 2 ... | 2007 | 17942608 |
| regulation of surfactant protein d in the mouse female reproductive tract in vivo. | surfactant protein d (sp-d) plays a role in innate immunity in the lung and is expressed at many other mucosal surfaces throughout the human body. in this study, we show that sp-d mrna and protein are present in the murine female reproductive tract; i.e. in the vagina, cervix, uterus and oviduct. sp-d protein is primarily localized to epithelial cells lining the genital tract and is also present in secretory material within the lumen of the uterus and cervix. the levels of sp-d mrna in the uteru ... | 2007 | 17954522 |
| a role for matrix metalloproteinase-9 in pathogenesis of urogenital chlamydia muridarum infection in mice. | matrix metalloproteinases (mmps) are a family of host-derived enzymes involved in the turnover of extracellular matrix (ecm) molecules and the processing of cytokines, chemokines and growth factors. we have previously reported that global inhibition of mmp in chlamydia muridarum urogenital tract infection of susceptible strains of female mice impeded ascension of c. muridarum into the upper genital tract, blunted acute inflammatory responses and reduced the rate of formation of chronic disease. ... | 2007 | 18023394 |
| chlamydia muridarum infection subverts dendritic cell function to promote th2 immunity and airways hyperreactivity. | there is strong epidemiological evidence that chlamydia infection can lead to exacerbation of asthma. however, the mechanism(s) whereby chlamydial infection, which normally elicits a strong th type 1 (th1) immune response, can exacerbate asthma, a disease characterized by dominant th type 2 (th2) immune responses, remains unclear. in the present study, we show that chlamydia muridarum infection of murine bone marrow-derived dendritic cells (bmdc) modulates the phenotype, cytokine secretion profi ... | 2008 | 18250429 |
| immunoproteomic discovery of novel t cell antigens from the obligate intracellular pathogen chlamydia. | chlamydia infections cause substantial morbidity worldwide and effective prevention will depend on a vaccine. since chlamydia immunity is t cell-mediated, a major impediment to developing a molecular vaccine has been the difficulty in identifying relevant t cell ags. in this study, we used a combination of affinity chromatography and tandem mass spectrometry to identify 13 chlamydia peptides among 331 self-peptides presented by mhc class ii (i-a(b)) molecules from bone marrow-derived murine dend ... | 2008 | 18250455 |
| antigen-specific cd4+ t cells produce sufficient ifn-gamma to mediate robust protective immunity against genital chlamydia muridarum infection. | chlamydia has been shown to evade host-specific ifn-gamma-mediated bacterial killing; however, ifn-gamma-deficient mice exhibit suboptimal late phase vaginal chlamydia muridarum clearance, greater dissemination, and oviduct pathology. these findings introduce constraints in understanding results from murine chlamydial vaccination studies in context of potential implications to humans. in this study, we used mice deficient in either ifn-gamma or the ifn-gamma receptor for intranasal vaccination w ... | 2008 | 18292563 |
| endogenous ifn-gamma production is induced and required for protective immunity against pulmonary chlamydial infection in neonatal mice. | chlamydia trachomatis infection in neonates, not adults, has been associated with the development of chronic respiratory sequelae. adult chlamydial infections induce th1-type responses that subsequently clear the infection, whereas the neonatal immune milieu in general has been reported to be biased toward th2-type responses. we examined the protective immune responses against intranasal chlamydia muridarum challenge in 1-day-old c57bl/6 and balb/c mice. infected c57bl/6 pups displayed earlier c ... | 2008 | 18322226 |
| nk cells contribute to intracellular bacterial infection-mediated inhibition of allergic responses. | to experimentally examine the hygiene hypothesis, here we studied the effect of chlamydial infection on the development of allergic responses induced by ova and the involvement of nk cells in this process using a mouse model of airway inflammation. we found that prior chlamydia muridarum infection can inhibit airway eosinophilic inflammation and mucus production induced by allergen sensitization and challenge. the inhibition was correlated with an alteration of allergen-driven cytokine-producing ... | 2008 | 18354185 |
| characterization of murine dendritic cell line jaws ii and primary bone marrow-derived dendritic cells in chlamydia muridarum antigen presentation and induction of protective immunity. | dendritic cells (dcs) appear to orchestrate much of the immunobiology of chlamydia infection, but most studies of chlamydia-dc interaction have been limited by the availability and heterogeneity of primary bone marrow-derived dcs (bmdcs). we therefore evaluated the immunobiology of chlamydia muridarum infection in an immortal dc line termed jaws ii derived from bmdcs of a c57bl/6 p53-knockout mouse. jaws ii cells were permissive to the developmental cycle of chlamydia. infection-induced cell dea ... | 2008 | 18362126 |
| rna interference screen identifies abl kinase and pdgfr signaling in chlamydia trachomatis entry. | to elucidate the mechanisms involved in early events in chlamydia trachomatis infection, we conducted a large scale unbiased rna interference screen in drosophila melanogaster s2 cells. this allowed identification of candidate host factors in a simple non-redundant, genetically tractable system. from a library of 7,216 double stranded rnas (dsrna), we identified approximately 226 host genes, including two tyrosine kinases, abelson (abl) kinase and pdgf- and vegf-receptor related (pvr), a homolog ... | 2008 | 18369471 |
| chlamydia muridarum evades growth restriction by the ifn-gamma-inducible host resistance factor irgb10. | chlamydiae are obligate intracellular bacterial pathogens that exhibit a broad range of host tropism. differences in host tropism between chlamydia species have been linked to host variations in ifn-gamma-mediated immune responses. in mouse cells, ifn-gamma can effectively restrict growth of the human pathogen chlamydia trachomatis but fails to control growth of the closely related mouse pathogen chlamydia muridarum. the ability of mouse cells to resist c. trachomatis replication is largely depe ... | 2008 | 18424746 |
| type i ifns enhance susceptibility to chlamydia muridarum lung infection by enhancing apoptosis of local macrophages. | type i ifns (ifnis) have pleiotropic functions in regulating host innate and adaptive immune responses to pathogens. to elucidate the role of ifnis in host resistance to chlamydial infection in vivo, we compared ifn-alpha/beta receptor knockout (ifnar(-/-)) and wild-type control mice in susceptibility to chlamydia trachomatis mouse pneumonitis (chlamydia muridarum) lung infection. we found that the ifnar(-/-) mice were significantly more resistant to c. muridarum infection showing less bacterial ... | 2008 | 18641348 |
| liposome delivery of chlamydia muridarum major outer membrane protein primes a th1 response that protects against genital chlamydial infection in a mouse model. | immunity to chlamydia is thought to rely on interferon (ifn)-gamma-secreting t helper cells type 1 (th1) with an additional effect of secreted antibodies. a need for th1-polarizing adjuvants in experimental chlamydia vaccines has been demonstrated, and antigen conformation has also been reported as being important for raising protective immunity. | 2008 | 18652549 |
| type i interferon signaling exacerbates chlamydia muridarum genital infection in a murine model. | type i interferons (ifns) induced during in vitro chlamydial infection exert bactericidal and immunomodulatory functions. to determine the precise role of type i ifns during in vivo chlamydial genital infection, we examined the course and outcome of chlamydia muridarum genital infection in mice genetically deficient in the receptor for type i ifns (ifnar(-/-) mice). a significant reduction in chlamydial shedding and duration of lower genital tract infection was observed in ifnar(-/-) mice in com ... | 2008 | 18663004 |
| poly-immunoglobulin receptor-mediated transport of iga into the male genital tract is important for clearance of chlamydia muridarum infection. | chlamydia trachomatis is the most common sexually transmitted infection worldwide. while infection in females requires a th1 response for clearance, such a response in males may disrupt the immune privileged nature of the male reproductive tract, potentially contributing to infertility. | 2008 | 18803626 |
| role for the chlamydial type iii secretion apparatus in host cytokine expression. | in many important human pathogens, such as shigella and salmonella spp., the bacterial type iii secretion (t3s) apparatus is required to initiate inflammation via activation of caspase-1- or nf-kappab-dependent genes. using an ex vivo infection model, the goal of the present study was to determine whether the chlamydial t3s apparatus also modulates the host inflammatory response. infections of mouse peritoneal macrophages were performed with chlamydia muridarum, and the expression of inflammator ... | 2009 | 18852236 |
| a real-time quantitative polymerase chain reaction assay for the detection of chlamydia in the mouse genital tract model. | chlamydia trachomatis is a human pathogen that infects genital tracts in women. disease control may be achieved through development of an efficacious vaccine. a mouse genital tract model serves as a tool for evaluation of vaccine candidates. currently, assessment of infection in mice is performed by enumeration of inclusion-forming units (ifus) through microscopic counting of fluorescently stained bacteria. we have developed a highly sensitive real-time quantitative polymerase chain reaction (rt ... | 2009 | 19026505 |
| a vibrio cholerae ghost-based subunit vaccine induces cross-protective chlamydial immunity that is enhanced by cta2b, the nontoxic derivative of cholera toxin. | the vibrio cholerae ghost (rvcg) platform is an effective carrier and delivery system for designing efficacious chlamydia vaccines. we investigated whether cta2b, the nontoxic derivative of cholera toxin, can augment protective immunity conferred by an rvcg-based chlamydial vaccine and enhance cross-protection against heterologous chlamydial strains. an rvcg vaccine coexpressing chlamydial major outer membrane protein and cta2b was genetically constructed and antigens were targeted to the inner ... | 2009 | 19040663 |
| chlamydia infection causes loss of pacemaker cells and inhibits oocyte transport in the mouse oviduct. | chlamydia trachomatis is a common sexually transmitted bacterial infection that results in health care costs in the united states that exceed $2 billion per year. chlamydia infections cause damage to the oviducts, resulting in ectopic pregnancy and tubal factor infertility, but the reasons for defective oviduct function are poorly understood. we have investigated the role of oviduct contractions in egg transport and found that underlying electrical pacemaker activity is responsible for oviduct m ... | 2009 | 19109220 |
| novel chlamydia muridarum t cell antigens induce protective immunity against lung and genital tract infection in murine models. | using a combination of affinity chromatography and tandem mass spectrometry, we recently identified 8 mhc class ii (i-a(b)) -bound chlamydia peptides eluted from dendritic cells (dcs) infected with chlamydia muridarum. in this study we cloned and purified the source proteins that contained each of these peptides and determined that three of the eight peptide/protein ags were immunodominant (pmpg-1, rplf, and pmpe/f-2) as identified by ifn-gamma elispot assay using splenocytes from c57bl/6 mice r ... | 2009 | 19155509 |
| blockade of epithelial membrane protein 2 (emp2) abrogates infection of chlamydia muridarum murine genital infection model. | new methods are needed to eradicate or prevent chlamydia trachomatis infections. blockade of epithelial membrane protein 2 (emp2) by genetic silencing or neutralizing polyclonal antibody reduced chlamydial infectivity in vitro. this study tests the prediction that recombinant anti-emp2 diabody could reduce early chlamydial infection of the genital tract in vivo. in a murine infection model, pretreatment with anti-emp2 diabody, as compared with control diabody, significantly reduced bacterial loa ... | 2009 | 19159428 |
| identification of dendritic cell subsets responding to genital infection by chlamydia muridarum. | dendritic cells (dcs) are central for the induction of t-cell responses needed for chlamydial eradication. here, we report the activation of two dc subsets: a classical cd11b+ (cdc) and plasmacytoid (pdc) during genital infection with chlamydia muridarum. genital infection induced an influx of cdc and pdc into the genital tract and its draining lymph node (iliac lymph nodes, iln) as well as colocalization with t cells in the iln. genital infection with c. muridarum also stimulated high levels of ... | 2009 | 19159430 |