Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| [epidemiology of felv and fiv infection in the federal republic of germany]. | in a nationwide study 6101 cats were tested for presence of feline leukemia virus (felv) antigen and for feline immunodeficiency virus (fiv) antibodies utilizing enzyme linked immunosorbent assay (elisa). 21.8% of the german cat population may be felv- and/or fiv-positive. of the animals tested, 13.4% were found to be felv carriers, while 8.4% showed evidence of fiv infection. infection with both viruses was identified in 2.1% of the cats tested. of the animals showing clinical symptoms, nearly ... | 1994 | 8048038 |
| photopheresis. | 1994 | 8050928 | |
| vaccination against feline leukaemia virus. | 1994 | 8080515 | |
| vaccination against feline leukaemia virus. | 1994 | 8080585 | |
| [vaccination of cats against infection with feline leukemia virus (felv): first recombinant vaccine and the effect of a pre-existing infection with feline immunodeficiency virus (fiv)]. | a new recombinant felv vaccine was evaluated in 30 specified pathogen-free cats 10 months of age cats. the vaccine consisted of the non-glycosylated felv envelope protein p45, aluminium hydroxide and a saponin adjuvant. the cats (n = 18) were vaccinated twice intramuscularly, 3 weeks apart. all animals were challenged intraperitoneally with felv subgroup a, 18 weeks later. while 94% of the vaccinated cats showed no viraemia or were only transiently viraemic, 80% of the non-vaccinated animals bec ... | 1994 | 7801087 |
| uses of flow cytometry in virology. | this article reviews some of the published applications of flow cytometry for in vitro and in vivo detection and enumeration of virus-infected cells. sample preparation, fixation, and permeabilization techniques for a number of virus-cell systems are evaluated. the use of flow cytometry for multiparameter analysis of virus-cell interactions for simian virus 40, herpes simplex viruses, human cytomegalovirus, and human immunodeficiency virus and its use for determining the effect of antiviral comp ... | 1994 | 7530594 |
| ultrasensitive retrovirus detection by a reverse transcriptase assay based on product enhancement. | reverse transcriptase (rt) is an indispensable component of infectious retroviruses. we have developed an ultrasensitive rt test in which rna of bacteriophage ms2 serves as the template for rt-mediated cdna synthesis. a fragment of the cdna is selectively amplified by polymerase chain reaction and the amplification product is analyzed by southern blot hybridization or enzyme immunoassay. the procedure was 10(6) to 10(7) times more sensitive than a conventional rt test and detected as little as 1 ... | 1994 | 7509077 |
| recombination between feline exogenous and endogenous retroviral sequences generates tropism for cerebral endothelial cells. | brain tissues of domestic cats that died of aplastic anemia from infection with either parental feline leukemia virus (felv), subgroup c, or a mixture of felv-c and recombinants between felv-c and an endogenous felv provirus were examined by the immunoperoxidase staining technique using a monoclonal antibody (c11d8) directed against an epitope of the viral surface glycoprotein (su). positive staining of the central nervous system (cns) capillary endothelial cells with no labeling on neuronal or ... | 1994 | 8311118 |
| genetic determinants of feline leukemia virus-induced lymphoid tumors: patterns of proviral insertion and gene rearrangement. | the genetic basis of feline leukemia virus (felv)-induced lymphoma was investigated in a series of 63 lymphoid tumors and tumor cell lines of presumptive t-cell origin. these were examined for virus-induced rearrangements of the c-myc, flvi-2 (bmi-1), fit-1, and pim-1 loci, for t-cell receptor (tcr) gene rearrangements, and for the presence of env recombinant felv (felv-b). the myc locus was most frequently affected in naturally occurring lymphomas (32%; n = 38) either by transduction (21%) or b ... | 1994 | 7966623 |
| comparison of fibrosarcomas that developed at vaccination sites and at nonvaccination sites in cats: 239 cases (1991-1992). | questionnaires were sent to veterinarians who had submitted a fibrosarcoma from a cat to the surgical pathology services of the veterinary schools of the university of pennsylvania and tufts university between jan 1, 1991 and june 30, 1992. questionnaire items included signalment, felv and feline immunodeficiency virus status, site of sarcoma, vaccination site, vaccines used, treatment, biologic behavior of the tumor, and final outcome. data were analyzed, using student's t-test for continuous d ... | 1994 | 7698923 |
| pathogenicity of a subgroup c feline leukemia virus (felv) is augmented when administered in association with certain felv recombinants. | there is evidence to suggest that infectious feline leukemia viruses (felvs) may be altered biologically because of homologous recombination with non-infectious endogenous felv (enfelv) sequences in the infected cells. to evaluate the role of such recombination events in felv pathogenesis, a molecular clone of subgroup c felv, sarma strain (fsc), was tested for induction of aplastic anemia in the absence or presence of mixtures of recombinants between fsc and an enfelv element. in the recombinan ... | 1994 | 8259654 |
| conversion of human fibroblasts to tissue macrophages by the snyder-theilen feline sarcoma virus (st:fesv(felv)): productive infection by leishmania major. | the decisive role of macrophages in t-cell differentiation is best exemplified by cutaneous leishmaniasis. during infection, leishmania attach to macrophages, the only site of replication for the parasite. we have recently demonstrated the conversion of human fibroblasts to tissue macrophages (tm) by transduction with the snyder-theilen feline sarcoma virus (st:fesv-(felv)). since leishmania have tropism only for macrophages, we have used the parasite to ascertain the functional phenotype of the ... | 1994 | 7721332 |
| felv incidence. | 1994 | 8160342 | |
| engineering of the human-immunodeficiency-virus-type-1 (hiv-1) reverse transcriptase gene to prevent dimerization of the expressed chimaeric protein: purification and characterization of a monomeric hiv-1 reverse transcriptase. | we report here a human-immunodeficiency-virus-type-1 (hiv-1) recombinant reverse transcriptase (rt) engineered to contain a 26-amino-acid linker insertion from the tether domain of feline leukaemia virus (flv) rt. the chimaeric protein was expressed in escherichia coli and migrated on sds/page as a 68 kda band. a monomeric form of the chimaeric hiv-1 rt has been prepared by the coordinated applications of immobilized-metal-affinity chromatography and gel filtration on superose 12 columns. the mo ... | 1994 | 7514879 |
| the c-kit proto-oncogene receptor is expressed on a subset of human cd3-cd4-cd8- (triple-negative) thymocytes. | the c-kit receptor is a tyrosine-kinase transmembrane receptor first identified as an oncogene in the hz4-feline leukemia virus and later found to be important in hematopoiesis in mice. the ligand for this receptor (steel factor) can stimulate hematopoiesis both in vitro and in vivo. to study the pattern of c-kit receptor expression in normal human hematopoietic progenitor cells, we prepared a monoclonal antibody (9b9) against human c-kit receptor by using a synthetic peptide (amino acids 476-50 ... | 1994 | 7522182 |
| differential antiviral activities and intracellular metabolism of 3'-azido-3'-deoxythymidine and 2',3'-dideoxyinosine in human cells. | dideoxynucleosides such as 3'-azido-3'-deoxythymidine (azt) and 2',3'-dideoxyinosine (ddi) can effectively inhibit the replication of human immunodeficiency virus (hiv) in t lymphoid cells. there is evidence that hiv can infect and replicate in other cells including monocytoid cells and macrophages. the present study compared the antiretroviral activities of ddi and azt in three lineages of human cells, i.e., molt4 (t lymphocytoid, cd4+), u937 (monocytoid, cd4+), and ht1080 (fibroblastoid, cd4-) ... | 1994 | 7526781 |
| viral diseases as a threat to free-living wild cats (felis silvestris) in continental europe. | 1994 | 7975059 | |
| infection of cats with molecularly cloned and biological isolates of the feline immunodeficiency virus. | molecularly cloned viruses are considered essential reagents for characterizing viral domains responsible for infectivity and disease pathogenesis in the host. the infectivity and hematological alterations associated with two molecularly cloned isolates of feline immunodeficiency virus (fiv-pppr and fiv-pf34) and an uncloned isolate (fiv-ppr) were assessed by inoculation of cats. inoculated cats were tested for viral antibody, viremia, and clinical pathological disease. peripheral blood mononucl ... | 1994 | 7975256 |
| is it possible to catch leukaemia from a cat? | 1994 | 7983981 | |
| vaccination and fibrosarcomas in cats. | 1994 | 8009792 | |
| hemostatic disorders in feline immunodeficiency virus-seropositive cats. | the hemostatic function of 40 feline immunodeficiency virus (fiv) seropositive and 8 fiv and feline leukemia virus (felv) seropositive cats was evaluated and compared with reference values from 30 clinically healthy cats. the fiv-positive cats were divided into 3 groups: group i included asymptomatic carriers; group ii comprised sick fiv-infected cats with illnesses not likely to influence the hemostatic system; and group iii included fiv-positive cats with diseases potentially associated with c ... | 1994 | 7837113 |
| abnormal processing of a recombinant feline leukemia virus envelope polyprotein and its interference with subgroup c virus infection. | processing of the env polyprotein of a noninfectious feline leukemia virus (felv) recombinant, named r6gp, was examined in human-transfected cells. the r6gp provirus was previously generated in the frame of felv, subgroup b, ga clone with substitution of all but 40 c-terminal amino acid sequences of the surface glycoprotein (su) from an endogenous felv provirus element (cfe-6). although r6gp produced a normal size (85 kda) env glycoprotein precursor, the product, unlike the precursor of the pare ... | 1994 | 8009844 |
| defective endogenous proviruses are expressed in feline lymphoid cells: evidence for a role in natural resistance to subgroup b feline leukemia viruses. | endogenous feline leukemia virus (felv)-related sequences (enfelv) are a family of proviral elements found in domestic cats and their close relatives. these elements can recombine with exogenous, infectious felvs of subgroup a (felv-a), giving rise to host range variants of felv-b. we found that a subset of defective enfelv proviruses is highly expressed in lymphoma cell lines and in a variety of primary tissues, including lymphoid tissues from healthy specific-pathogen-free cats. at least two r ... | 1994 | 8138999 |
| evolution of feline leukemia virus variant genomes with insertions, deletions, and defective envelope genes in infected cats with tumors. | in order to study retroviral variation, selection, and viral correlates of in vivo pathogenicity, we documented the evolution of feline leukemia virus (felv) variants in cats that died with thymic lymphoma after infection with molecularly cloned subgroup a felv. using genomic dna from cat necropsy samples, we employed pcr to amplify and clone the envelope gene, which is a major determinant of the specific pathogenicity of different felv variants. in the envelope gene, mutations encoded scattered ... | 1994 | 8139030 |
| lack of evidence for infection with known human and animal retroviruses in patients with chronic fatigue syndrome. | we investigated 21 patients with chronic fatigue syndrome who were identified through the surveillance system of the centers for disease control and prevention (cdc) in atlanta for the presence of several human and animal retroviruses. in addition, we evaluated 21 cdc employee controls matched with the patients for age (+/- 5 years), gender, and race. the viruses tested included human t-lymphotropic viruses types i and ii; human spuma retrovirus; simian t-lymphotropic virus type i; simian retrov ... | 1994 | 8148438 |
| induction of feline acquired immune deficiency syndrome by feline leukemia virus: immuno- and neuroendocrine dysfunctions. | young cats, when chronically infected with feline leukemia virus (felv), developed feline acquired immune deficiency syndrome (faids). the syndrome was associated with a sequence of dysfunctions in the hypothalamic-pituitary-gonadal (hpg) and the immune system, manifested in the reduction of luteinizing hormone-releasing hormone (lhrh), follicle stimulating hormone (fsh), luteinizing hormone (lh), and testosterone in blood plasma. the average fsh and lh (in plasma or lymphocyte), testosterone, a ... | 1994 | 8171057 |
| evaluation of a feline leukemia virus vaccine in a controlled natural transmission study. | twenty-six 8-week-old specific-pathogen-free cats were vaccinated subcutaneously with 2 doses of a commercially available felv vaccine, and 26 age-matched specific-pathogen-free cats were similarly vaccinated with a placebo vaccine containing the same adjuvant as the felv vaccine. cats then were randomly assigned to 2 groups of 26 cats (13 felv-vaccinated cats and 13 control cats), and each group was housed with 5 cats previously inoculated with felv. all cats were tested biweekly for the next 2 ... | 1994 | 8188511 |
| retroviral transmission by the transplantation of connective-tissue allografts. an experimental study. | the transmission of a retrovirus by the transplantation of allografts of connective tissues was studied in a feline model with use of the feline leukemia virus, a retrovirus with a replication cycle and pathological characteristics similar to those of the human immunodeficiency virus. the retrovirus was used to infect four specific-pathogen-free cats that were subsequently used as tissue donors. fresh allografts of menisci, patellar ligaments, and patellar ligament and bone composites were harve ... | 1994 | 8027111 |
| safety aspects of a vaccine for cats containing a toxoplasma gondii mutant strain. | 1994 | 7804276 | |
| cutaneous t-cell lymphoma in a cat. | an 8-year-old castrated male cat was examined because of a chronic, nonhealing, ulcerative lesion on the left hind limb. cutaneous lymphoma was diagnosed on the basis of the morphologic appearance of malignant cells and pautrier's microabscesses on light and electron microscopic examination. the tumor was found to be of t-cell origin by use of a polyclonal antibody recognizing t-cell antigen. results of serum elisa for felv were negative. the gp70 antigen of felv was not detected immunohistochem ... | 1994 | 8163416 |
| structure and self assembly of a retrovirus (felv) proline rich neutralization domain. | the 60 amino acid proline-rich neutralization domain of the external surface unit glycoprotein of feline leukemia virus was chemically synthesized in total and in fragments. we examined the ability of these retroviral peptides to form ordered conformations using 1h-nmr, circular dichroism spectroscopy, and intrinsic viscosity measurements. one dimensional nuclear magnetic resonance spectroscopy revealed that the 60 amino acid peptide could form a stable, folded structure that was long-lived, as ... | 1994 | 8204217 |
| [distribution of p27 and gp70 feline leukemia virus antigens in various tissues]. | application of immunocytochemical methods (dp, ip, pap, apaap and ip-ip) has confirmed the existence of p27 and gp70 feline leukosis viral antigens (felv) in various tissues of 22 cats. both viral antigens were found in bone marrow stem cells, but p27 antigens were mostly found in epithelial cells of intestinal crypts. in splenic t-lymphocytes and mediastinal lymph nodes the predominance of gp70 antigens in felv was confirmed, while the tropism of leukosis viruses in the lung was inclined to epi ... | 1994 | 8560843 |
| feline leukemia virus detection by immunohistochemistry and polymerase chain reaction in formalin-fixed, paraffin-embedded tumor tissue from cats with lymphosarcoma. | the prevalence of feline leukemia virus (felv) antigen and dna was assessed in formalin-fixed, paraffin-embedded tumor tissues from 70 cats with lymphosarcoma (lsa). tissue sections were tested for felv gp70 antigen using avidinbiotin complex (abc) immunohistochemistry (ihc); dna was extracted and purified from the same tissue blocks for polymerase chain reaction (pcr) amplification of a 166 base pair region of the felv long terminal repeat (ltr). results were related to antemortem felv enzyme-l ... | 1993 | 8269365 |
| felv vaccination. | 1993 | 8279119 | |
| thrombocytopenia in cats: a retrospective study of 41 cases. | the prevalence of feline thrombocytopenia (< 200,000 platelets/microl) at north carolina state university, college of veterinary medicine teaching hospital, from january 1985 to march 1990, was 1.2% (41/3300). cats were divided into six categories based on clinical diagnoses: 29% (12/41) had infectious disease, 20% (8/41) had neoplasia, 7% (3/41) had cardiac disease, 2% (1/41) had primary immune-mediated disease, 22% (9/41) had multiple diseases, and 20% (8/41) had disorders of unknown etiology. ... | 1993 | 8263843 |
| chronic feline leukemia virus infection alters arachidonic acid proportions in vivo and in vitro. | the polyunsaturated omega-6 fatty acid, arachidonic acid ([aa] 20:4n-6), is both the key of the immunoregulatory substances, prostaglandins, and leukotrienes, and an essential component of immune cell membrane phospholipids, providing stability and flexibility to ensure cellular function. to explore possible effects of the physiological burden of viral replication in chronic viral infections on aa availability, plasma total esterified fatty acid (fa) proportions were measured in the feline leuke ... | 1993 | 8380929 |
| immunogenicity and efficacy of a commercial feline leukemia virus vaccine. | twenty young adult specific pathogen-free cats were randomly divided into two groups of 10 animals each. one group was vaccinated with two doses of feline leukemia virus vaccine according to the manufacturer's recommendations. all 20 cats were challenge exposed oronasally (4 times over a 1-week period), beginning 3 weeks after immunization, with a virulent subgroup a strain of felv (ct600-felv). the severity of the felv infection was enhanced by treating the cats with methylprednisolone acetate ... | 1993 | 8384261 |
| eosinophilic pleural or peritoneal effusions in dogs and cats: 14 cases (1986-1992). | case records of 9 dogs and 5 cats with eosinophilic effusions were reviewed. the animals ranged from 11 months to 13 years old. seven animals had pleural effusions, 5 had peritoneal effusions, and 2 had pleural and peritoneal effusions. neoplasia was confirmed in 6 animals and suspected in 1. eosinophilic pleural effusion was diagnosed 2 days after pneumothorax developed as a consequence of thoracic tube placement in a cat, and pneumothorax was diagnosed in another cat with eosinophilic peritone ... | 1993 | 8320159 |
| establishment and characterization of a feline large granular lymphoma cell line expressing interleukin 2 receptor alpha-chain. | a feline large granular lymphocyte (lgl) cell line was established from a cat with an alimentary-form lymphoma. this cell line, designated as fgl, had many large azurophilic granules in the cytoplasm, which were typical to lgl cells. proviral genome of feline leukemia virus was detected in the chromosomal dna of fgl cells, and reverse transcriptase activity was also demonstrated in the culture supernatant. furthermore, we found expression of interleukin 2 (il-2) receptor alpha-chain on the cell ... | 1993 | 8286547 |
| synthesis of large multideterminant peptide immunogens using a poly-proline beta-turn helix motif. | we report the synthesis and characterization of a novel secondary structural motif, the poly-proline beta-turn helix. this motif is found in the proline-rich immunogenic domains of feline retroviruses, mucins and many proline-rich tandem repeat-containing surface proteins. we describe the synthetic methodology to directly synthesize natural and engineered immunogens of up to 100+ amino acids. using manual solid-phase peptide synthesis modified for optimal efficiency, we directly synthesized 1, 2 ... | 1993 | 8292850 |
| computed tomography and magnetic resonance findings of meningeal syndrome in a leukemic cat. | a 3-year-old japanese domestic cat with a diagnosis of lymphocytic leukemia showed severe generalized seizures in the course of chemotherapy after leukemic condition was improved clinically. computed tomography (ct) and magnetic resonance (mr) imaging of the brain were carried out. both contrast procedures disclosed enhancements at the falx cerebri and the margin of cerebral cortex. among these procedures contrast mr imaging demonstrated the lesion most clearly. cytological examination of cerebr ... | 1993 | 8117801 |
| seroprevalence of infectious disease agents in free-ranging florida panthers (felis concolor coryi). | serum samples obtained from 38 free-ranging florida panthers (felis concolor coryi) in southern florida, march 1978 through february 1991, were tested for antibodies against eight bacterial, parasitic, and viral disease agents. sera were positive for antibodies against feline panleukopenia virus (fpv) (78%), feline calicivirus (56%), feline immunodeficiency virus/puma lentivirus (37%), feline enteric coronavirus/feline infectious peritonitis virus (19%), and toxoplasma gondii (9%). all samples w ... | 1993 | 8445789 |
| distinct superinfection interference properties yet similar receptor utilization by cytopathic and noncytopathic feline leukemia viruses. | cell killing by cytopathic retroviruses is often associated with a delay or failure in the establishment of superinfection interference. superinfection has been observed during t-cell killing and fatal immunodeficiency disease induction by the feline leukemia virus (felv) chimera felv-faids-eecc, containing the surface envelope glycoprotein (su) of felv-faids clone 61c. we demonstrate here that 61c su has a defect that results in a nearly complete failure to establish superinfection interference ... | 1993 | 8394443 |
| advances in the understanding of feline leukaemia virus. | 1993 | 8384389 | |
| [retrovirus infections of the cat: feline leukemia virus (felv) and feline immunodeficiency virus (fiv). a review from the clinical viewpoint]. | diseases caused by felv are very variable. they can be classified in felv associated, proliferative and neoplastic signs. moreover there are other nonspecific diseases and clinically inapparent infections. felv as well as fiv may cause immunodeficiency syndromes; this is the main problem in fiv infections. in contrast to humans fiv does not induce specific secondary diseases. positive diagnostic results obtained by use of commercial test kits must be verified by other methods. methods of treatme ... | 1993 | 8122242 |
| fusion activity dissociated from replication ability in feline immunodeficiency virus (fiv) in human cells. | multinucleated-giant-cell formation followed by cell killing was observed after cocultivation of the feline immunodeficiency virus (fiv)-producing feline t-cell line 3201/fiv with various human cells, including t-cell lines carrying human t-cell lymphotropic virus type i (htlv-i). the susceptibility to giant cell formation varied with the cell lines tested. cocultivation of irradiated 3201/fiv cells with mt-2 cells resulted in giant cell formation as early as 2 h in culture, with striking resemb ... | 1993 | 8254466 |
| epidemiologic evidence for a causal relation between vaccination and fibrosarcoma tumorigenesis in cats. | within the past 2 years, a putative causal relationship has been reported between vaccination against rabies and the development of fibrosarcomas at injection sites in cats. a retrospective study was undertaken, involving 345 cats with fibrosarcomas diagnosed between january 1991 and may 1992, to assess the causal hypothesis. cats with fibrosarcomas developing at body locations where vaccines are typically administered (n = 185) were compared with controls (n = 160) having fibrosarcomas at locat ... | 1993 | 8257557 |
| effects of preactivated mc540 in the treatment of lymphocytic plasmacytic stomatitis in feline leukemia virus and feline immunodeficiency virus positive cats. | photoactive compounds and drugs are used therapeutically as antibacterial, antiviral and antitumor agents. this report examines the use of a photoactive compound, preactivated merocyanine 540 (pmc540), in the treatment of stomatitis in two cats that are both feline immunodeficiency virus (fiv) positive. one of the cats was also feline leukemia virus (felv) positive. dramatic short term improvement is reported with the dosage regimen and complications. | 1993 | 8148094 |
| sequence and functional characterization of feline interleukin 2. | since the discovery of its involvement in the pathogenesis of feline immunodeficiency virus infection ("cat aids") and feline leukemia virus infection, the role of feline interleukin 2 (il-2) has been a focus of particular interest. the purpose of this study was to clone feline il-2 cdna, as well as synthesize bioactive recombinant feline il-2. the isolation of cdna encoding feline il-2 was carried out using a pcr-based strategy and screening of a feline leukocyte cdna library. feline il-2 consi ... | 1993 | 8352761 |
| feline leukemia virus. immunization and prevention. | our understanding of the pathogenesis of felv infection is little changed from what was described by hardy and his colleagues in the mid-1970s. the prevention of felv infection consists, first, of avoiding the agent and, second, of providing optimum immunologic resistance. in multi-cat environments, the former is achieved through test-and-removal methods perennially reviewed in the literature and by minimizing exposure to outdoor cats. the latter is possible by attempting to maintain a low-stres ... | 1993 | 8380657 |
| induction of feline leukaemia virus-neutralizing antibodies by immunization with synthetic peptides derived from the felv env gene. | the surface glycoprotein, gp70, of feline leukaemia virus (felv) contains sites which are important in inducing neutralizing antibodies. using synthetic peptides corresponding to nucleotide sequence 729-957 (amino acid sequence 243-319) of felv-a/glasgow-1, the antigenicity and immunogenicity of this part of the viral surface glycoprotein were investigated. the region contains two highly conserved domains separated by a variable region (vr4), when compared with felv of subgroups b and c, and an ... | 1993 | 7692683 |
| felv vaccination. | 1993 | 8296439 | |
| in vitro infection of human bone marrow by feline leukemia viruses. | four subgroup feline leukemia viruses (felv) were tested for their ability to infect primary cultures of human bone marrow in vitro. using three sequential exposures to both concentrated and unconcentrated virus, felv infection of human bone marrow was documented by indirect immunofluorescence, elisa, and polymerase chain reaction (pcr) assays. based on comparison to known standards, it was estimated that between 5 and 10% of the bulk human marrow culture could be infected by felv. further evide ... | 1993 | 8382406 |
| protection of cats against feline leukemia virus by vaccination with a canarypox virus recombinant, alvac-fl. | two alvac (canarypox virus)-based recombinant viruses expressing the feline leukemia virus (felv) subgroup a env and gag genes were assessed for their protective efficacy in cats. both recombinant viruses contained the entire gag gene. alvac-fl also expressed the entire envelope glycoprotein, while alvac-fl(dl is) expressed an env-specific gene product deleted of the putative immunosuppressive region. although only 50% of the cats vaccinated with alvac-fl(dl is) were protected against persistent ... | 1993 | 8383248 |
| evaluation of cofactor effect of feline syncytium-forming virus on feline immunodeficiency virus infection. | although feline immunodeficiency virus (fiv) and the unrelated retrovirus feline leukemia virus (felv) are associated with acquired immune deficiency in cats, experimental and field evidence indicates that coinfection with both viruses may lead to more serious disease syndrome. a third feline retrovirus, feline syncytium-forming virus (fesfv), which is far more prevalent than either fiv or felv and is considered nonpathogenic in nature, is consistently coisolated from sick, fiv-infected cats. to ... | 1993 | 8391229 |
| mutation of amino acids within the gibbon ape leukemia virus (galv) receptor differentially affects feline leukemia virus subgroup b, simian sarcoma-associated virus, and galv infections. | the three type c retroviruses, gibbon ape leukemia virus (galv), simian sarcoma-associated virus (ssav), and feline leukemia virus subgroup b (felv-b), infect human cells by interacting with the same cell surface receptor, glvr1. using lacz retroviral pseudotypes and murine cells transfected with mutant glvr1 expression vectors, we show that the same 9-amino-acid region of human glvr1 is critical for infection by the three viruses. rat cells were not susceptible to infection by lacz (felv-b) pse ... | 1993 | 8411376 |
| granulated round cell tumor of cats. | morphologic and biologic features of five feline granulated round cell tumours were compared with those previously reported to be of globule leukocyte and large granular lymphocyte origin. the five cats ranged from 6 to 9 years of age and presented with nonspecific gastrointestinal signs. four of the five cats were tested for feline leukemia virus and were negative by enzyme-linked immunosorbent assay. the neoplastic process involved the abdominal cavity in all cases, with a predilection for the ... | 1993 | 8470340 |
| reversal of feline leukemia virus infection by adoptive transfer of lectin/interleukin-2-activated lymphocytes, interferon-alpha, and zidovudine. | previous experimental studies utilizing human recombinant interferon-alpha-2b (ifn alpha-2b) alone or with zidovudine (azt) to treat established feline leukemia virus (felv) infection resulted in a significant reduction in circulating virus throughout a 49-day treatment period. however, the anti-felv effect of ifn alpha was limited by the production of ifn alpha-neutralizing antibodies detected 7 weeks after the start of treatment. azt without ifn alpha had no effect on circulating virus load. t ... | 1993 | 8399067 |
| enhanced immunosuppressive activity associated with metastatic lymphoma cells. | earlier reports from our laboratory showed that abelson virus-induced, highly malignant and liver metastatic raw117-h10 cells, but not the parental, less metastatic raw117-p cells, inhibited both t-cell and b-cell mitogen-induced proliferation of syngeneic normal murine spleen cells. similar inhibition was also noted when raw117-h10 cell surface molecules extracted with butanol were used instead of whole tumor cells. in this report we describe the suppressive properties of the butanol-extracted ... | 1993 | 8385575 |
| coincident involvement of flvi-2, c-myc, and novel env genes in natural and experimental lymphosarcomas induced by feline leukemia virus. | the flvi-2 locus is a target of insertional mutagenesis in thymic lymphosarcomas induced by feline leukemia virus (felv). flvi-2 encodes the gene bmi-1, whose product is implicated as a myc-collaborator in the induction of b- and t-cell lymphoma. we have examined the involvement of flvi-2 and myc in natural and experimentally induced felv-positive feline lymphosarcomas which are heterogeneous in anatomical origin, geographic origin, and strain of felv involved. we further compared these findings ... | 1993 | 8396818 |
| macrophage tropism of feline leukemia virus (felv) of subgroup-c and increased production of tumor necrosis factor-alpha by felv-infected macrophages. | erythroid aplasia is induced in cats by feline leukemia virus (felv) of subgroup c but not by felv of subgroup a. in an investigation of the role of macrophages in felv-c-induced diseases, the concentrations of felv and tumor necrosis factor-alpha (tnf-alpha) were compared between feline peritoneal macrophages incubated with felv of subgroup a or c. felv of both subgroups infected macrophages, but expression of felv-c was 21-fold higher than felv-a in peritoneal macrophages (p = .004). the super ... | 1993 | 8387834 |
| nucleotide sequence of the splice junction of feline leukemia virus envelope mrna. | the splice donor and acceptor sequences for the subgenomic envelope messenger rna of feline leukemia virus (felv) were determined. the splice junction was characterized for viral mrna from a prototype subgroup a felv and an immunodeficiency-inducing felv variant. thirty-seven of 38 partial envelope cdnas, cloned after pcr amplification from t cells infected with either virus, utilized the same splice donor and acceptor sites to generate a mrna that would be predicted to encode envelope protein. ... | 1993 | 8393248 |
| delayed cytopathicity of a feline leukemia virus variant is due to four mutations in the transmembrane protein gene. | two molecularly cloned, replication-defective variants of feline leukemia virus, called 61b and 61c, have both been shown to cause fatal immunodeficiency in cats when coinfected with a replication-competent, minimally pathogenic helper virus, but 61b exhibits a longer latency period between infection and disease (j. overbaugh, e. a. hoover, j. i. mullins, d. p. w. burns, l. rudensey, s. l. quackenbush, v. stallard, and p. r. donahue, virology 188:558-569, 1992). infection of the 3201 feline t-ce ... | 1993 | 8396654 |
| a common proviral integration region, fit-1, in t-cell tumors induced by myc-containing feline leukemia viruses. | feline leukemia viruses carrying transduced v-myc genes (myc-felv) induce tumors of clonal origin, suggesting that activated myc alone is not sufficient for tumorigenesis. to investigate the hypothesis that insertional mutagenesis plays a role by activating genes which collaborate with v-myc, we looked for evidence of common proviral integration sites in these tumors. by inverse polymerase chain reaction we identified a 6-kb domain, designated fit-1, in which felv proviruses were inserted in fou ... | 1993 | 8396812 |
| recombinant feline leukemia virus genes detected in naturally occurring feline lymphosarcomas. | using a polymerase chain reaction strategy aimed at detecting recombinant feline leukemia virus (felv) genomes with 5' env sequences originating from an endogenous source and 3' env sequences resulting from felv subgroup a (felv-a), we detected recombinant proviruses in approximately three-fourths of naturally occurring thymic and alimentary feline lymphosarcomas (lsas) and one-third of the multicentric lsas from cats determined to be felv capsid antigen positive by immunofluorescence assay. in ... | 1993 | 8388492 |
| interference with superinfection and with cell killing and determination of host range and growth kinetics mediated by feline leukemia virus surface glycoproteins. | the functions of the surface glycoproteins (su) of feline leukemia viruses (felvs) are of interest since these proteins mediate virus infection and interference and are critical determinants of disease specificity. in this study, we examined the biochemical and genetic determinants of su important to virus entry and cell killing. in particular, we developed and used vesicular stomatitis virus (vsv)/felv pseudotype virus interference assays to determine interference subgroupings and assess mechan ... | 1993 | 8389921 |
| flvi-2, a target of retroviral insertional mutagenesis in feline thymic lymphosarcomas, encodes bmi-1. | lc-felv is a myc-containing strain of feline leukemia virus which induces thymic lymphosarcoma in the domestic cat with short latency. a locus in feline dna, termed flvi-2, is commonly interrupted in naturally occurring and experimentally induced thymic lymphosarcomas containing lc-felv; thus, interruption of a gene encoded by flvi-2 may cooperate with the myc oncogene in the induction of t-cell tumors by lc-felv. clones homologous to flvi-2 have been isolated from a normal human thymus cdna lib ... | 1993 | 8390036 |
| photodynamic inactivation of retrovirus by benzoporphyrin derivative: a feline leukemia virus model. | the ability of a photosensitizer, benzoporphyrin derivative monoacid ring a (bpd-ma), and either broad-spectrum (400-1200 nm) or narrow-band (600-700 nm) red light to kill feline leukemia virus (felv) and felv-infected cat t cells (cell line 3201) was investigated in culture medium containing fetal calf serum and in blood from infected cats. a molecular clone of felv, 61e, is minimally pathogenic and productively infects 3201 cells while causing no change in rate of cell division, viability, or ... | 1992 | 1371895 |
| isolation and characterization of a retrovirus from the fish genus xiphophorus. | a cell line (bst) established from neoplastic embryonal tissues of the platyfish (xiphophorus maculatus) released spontaneously retrovirus-like particles. the particles have a buoyant density of 1.16 g/ml, a mean diameter of 100 nm and the morphology of immature retroviruses. the particle-associated proteins p70, p65, and p28 react with an antiserum directed against the major internal feline leukemia virus structural protein p27. the particles are associated with a reverse transcriptase. the pur ... | 1992 | 1374984 |
| biologically selected recombinants between feline leukemia virus (felv) subgroup a and an endogenous felv element. | in efforts to elucidate the proximal leukemogens that might be produced during a feline leukemia virus (felv) infection of cats, homologous recombinations between molecularly cloned exogenous and endogenous felv proviruses of known sequences were examined in cell cultures in vitro. a plasmid containing an infectious member of the most commonly occurring felv subgroup (felv subgroup a or felv-a) was coexpressed with noninfectious constructs containing the envelope (env) gene of an endogenously in ... | 1992 | 1381539 |
| cell lines produce factors that induce fetal hemoglobin in human bfue-derived colonies. | established cell lines were screened for secretion of activities than can stimulate fetal hemoglobin (hbf) production in adult burst-forming unit-erythroid (bfue) cultures. conditioned media from four cell lines, a human teratocarcinoma, an osteosarcoma, a bladder cell carcinoma, and feline leukemia virus (felv) a-infected feline fibroblasts (fef-a cells), consistently increased the relative production of fetal globin in bfue-derived colonies. in vitro translation of rna from these cells in xeno ... | 1992 | 1384795 |
| enzyme-linked immunosorbent assays for the detection of toxoplasma gondii-specific antibodies and antigens in the aqueous humor of cats. | serum and aqueous humor samples, collected from 14 clinically normal cats and 96 cats with clinical evidence of intraocular inflammation, were assayed with elisa for toxoplasma gondii-specific immunoglobulin m (igm), t gondii-specific igg, t gondii-specific antigens, total igg, and total igm. additionally, serum was assayed with elisa for feline leukemia virus p27 antigen and antibodies against the feline immunodeficiency virus as well as with an immunofluorescent antibody assay for antibodies a ... | 1992 | 1429123 |
| [the effectiveness of paramunization for the control of feline coryza]. | 20 cats in a cat home were treated prophylactically and therapeutically with baypamun hk. the animals were allocated into three groups as described. 7 freshly admitted clinically healthy cats were treated prophylactically on day 1, 2 and 9 with 1 ml baypamun hk (group i). 7 cats, who already were allocated for one year in the home and were sick of the feline respiratory disease complex were treated as described for group i (group ii). 6 further cats, who also showed symptoms of the feline respir ... | 1992 | 1524577 |
| synthetic hexapeptides derived from the transmembrane envelope proteins of retroviruses suppress n-formylpeptide-induced monocyte polarization. | retroviral infections are frequently associated with immunosuppression. retroviral transmembrane envelope proteins (tm proteins) play an important role in this phenomenon. cks-17, a synthetic heptadecapeptide, represents the immunosuppressive site of these retroviral tm proteins. here we support on the further delineation of this immunosuppressive site using cks-17-derived hexapeptides. the n-formyl-methionyl-leucyl-phenylalanine-induced monocyte polarization assay was used throughout this study ... | 1992 | 1541910 |
| simultaneous separation and purification of mononuclear and polymorphonuclear cells from the peripheral blood of cats. | peripheral blood mononuclear cells (pbmc) and polymorphonuclear cells (pmnc) play important roles in immunodeficiency diseases and aids-like syndromes in cats caused by feline leukemia virus (felv) and presumably also when caused by feline immunodeficiency virus (fiv). for comparative or functional studies it is advantageous or necessary to obtain these cells as separate entities from the same sample of an animal. therefore, we analyzed the technical parameters of obtaining, separating and purif ... | 1992 | 1556164 |
| use of 8-methoxypsoralen and long wavelength ultraviolet radiation for decontamination of platelet concentrates. | transmission of viral diseases through blood products remains a problem in transfusion medicine. we have developed a photochemical decontamination system (pcd) for platelet concentrates (pc) utilizing treatment with long wavelength ultraviolet radiation (uva, 320-400 nm) and 8-methoxypsorlan (8-mop). this system is capable of inactivating 25-30 logs/hour of bacteria e. coli or s. aureus, 6 logs/hour of bacteriophage fd, 0.9 log/hour of bacteriophage r17, and 1.1 logs/hour of feline leukemia viru ... | 1992 | 1617193 |
| evaluation of feline immunodeficiency virus and feline leukemia virus transmembrane peptides for serological diagnosis. | the general model for retrovirus transmembrane (tm) proteins proposed by gallaher et al. (w. r. gallaher, j. m. ball, r. f. garry, m. c. griffin, and r. c. montelaro, aids res. hum. retroviruses 5:431-440, 1989) suggests that all retrovirus tm proteins may contain an immunodominant domain (imd-tm peptide) located at the apex of the tm polypeptide. although this imd-tm peptide has been shown to be immunodominant in a variety of lentivirus infections, there has not been a detailed serological anal ... | 1992 | 1629349 |
| retroviral pseudotypes produced by rescue of a moloney murine leukemia virus vector by c-type, but not d-type, retroviruses. | human hos cells containing a moloney murine leukemia virus (mo-mlv) recombinant genome were infected by a panel of retroviruses. the c-type viruses simian sarcoma associated virus, feline leukemia virus subgroup b, and the feline endogenous virus rd114 were able to form pseudotypes with the mo-mlv genome, which transferred a selectable marker gene to target cells; however, human t cell leukemia virus-1 and the d-type viruses mason-pfizer monkey virus and simian retrovirus-1 failed to rescue the ... | 1992 | 1733113 |
| feline leukemia virus subgroup b uses the same cell surface receptor as gibbon ape leukemia virus. | pseudotypes of gibbon ape leukemia virus/simian sarcoma-associated virus (galv/ssav) and feline leukemia virus subgroup b (felv-b) have been constructed by rescuing a moloney murine leukemia virus vector genome with wild-type galv/ssav or felv-b. the resulting recombinant viruses utilized core and envelope proteins from the wild-type virus and conferred resistance to growth in l-histidinol upon infected cells by virtue of the hisd gene encoded by the vector genome. they displayed the host range ... | 1992 | 1309898 |
| novel gacg-hairpin pair motif in the 5' untranslated region of type c retroviruses related to murine leukemia virus. | we searched for the presence of common rna structural motifs in mammalian type c retroviruses related to murine leukemia viruses and the closely related avian spleen necrosis virus. a novel motif consisting of a pair of hairpins, called hairpin pair motif, was detected in the 5' untranslated regions of the genomes of these retroviruses. a combination of computational analyses that included the assessment of phylogenetic sequence conservation by multiple alignment, the search for regions with unu ... | 1992 | 1309906 |
| meeting report. report of meeting of section of clinical immunology and allergy, 11 march 1991. | 1992 | 1311382 | |
| feline leukemia virus: pathophysiology, prevention, and treatment. | 1992 | 1312884 | |
| detection of feline immunodeficiency proviral dna in peripheral blood lymphocytes by the polymerase chain reaction. | feline immunodeficiency virus (fiv) proviral dna was detected by the polymerase chain reaction method (pcr). pcr products were detected by gel electrophoresis and ethidium bromide staining. the p-10, p-15 and p-24 regions of the gag gene of fiv were chosen as the target sequences for amplification, and three primer pairs were prepared. the pcr products subjected to amplification with each primer pair were found to possess sites of digestion by a restriction enzyme, as hypothesized. they did not ... | 1992 | 1313618 |
| comparison of the viral promoter activities in feline cell lines (crfk and fcwf-4 cells). | 1992 | 1313705 | |
| insertional mutagenesis of flvi-2 in tumors induced by infection with lc-felv, a myc-containing strain of feline leukemia virus. | lc-felv is a myc-containing strain of feline leukemia virus (felv) which exhibits only partial transforming activity in vitro and in vivo. lc-felv infection in kittens may induce, but does not necessarily induce, thymic lymphosarcoma in viremic animals after a short latency. these observations suggest that infection with lc-felv is not sufficient to induce complete transformation and that another genetic event(s) is required. one possibility for such an event is that the integrating provirus act ... | 1992 | 1313907 |
| prevalence of feline leukemia virus and antibodies to feline immunodeficiency virus in cats in norway. | serum samples from 224 norwegian cats were analyzed for the presence of feline leukemia virus (felv) p27 common core antigen, and for antibodies to feline immunodeficiency virus (fiv). ninety specimens originated from the serum bank at the central referral clinic at the norwegian college of veterinary medicine, which had been collected during the years 1983-1989; 67 sera were submitted from veterinarian practitioners; while 67 sera originated from cats presented for euthanasia. the cats were cla ... | 1992 | 1316024 |
| cytotoxicity in feline leukemia virus subgroup-c infected fibroblasts is mediated by adherent bone marrow mononuclear cells. | the pathogenesis of retrovirus-induced erythroid aplasia in cats is unknown. in studies to define mechanisms of cytotoxicity associated with retroviral infections, bone marrow mononuclear cells (bmmc) from healthy specific pathogen-free cats were co-cultured with uninfected feline embryonic fibroblasts (fea cells) and fea cells infected with feline leukemia virus (felv) of subgroup a (fea-a) or subgroup c (fea-c). moderate to marked cytotoxicity (cpe) developed in co-cultures of bmmc and fea-c c ... | 1992 | 1316351 |
| pathogenesis of feline leukemia virus t17: contrasting fates of helper, v-myc, and v-tcr proviruses in secondary tumors. | a naturally occurring feline thymic lymphosarcoma (t17) provided the unique observation of a t-cell antigen receptor beta-chain gene (v-tcr) transduced by a retrovirus. the primary tumor contained three classes of feline leukemia virus (felv) provirus, which have now been characterized in more detail as (i) v-tcr-containing recombinant proviruses, (ii) v-myc-containing recombinant proviruses, and (iii) apparently full-length helper felv proviruses. the two transductions appear to have been indep ... | 1992 | 1316466 |
| identification of a putative receptor for subgroup a feline leukemia virus on feline t cells. | retrovirus infection is initiated by the binding of virus envelope glycoprotein to a receptor molecule present on cell membranes. to characterize a receptor for feline leukemia virus (felv), we extensively purified the viral envelope glycoprotein, gp70, from culture supernatants of felv-61e (subgroup a)-infected cells by immunoaffinity chromatography. binding of purified 125i-labeled gp70 to the feline t-cell line 3201 was specific and saturable, and scatchard analysis revealed a single class of ... | 1992 | 1316477 |
| recombination between feline leukemia virus subgroup b or c and endogenous env elements alters the in vitro biological activities of the viruses. | 1992 | 1316496 | |
| structure and pathogenicity of individual variants within an immunodeficiency disease-inducing isolate of felv. | we previously described the molecular cloning of a replication-defective variant of feline leukemia virus (felv) that induced fatal immunodeficiency in cats. eighteen proviruses have now been molecularly cloned from cats inoculated with the original isolate (felv-faids) or its in vivo passages. three were replication-competent and each of these was noncytopathic for the feline t-cell line, 3201. replication of the prototype, felv-61e, in cats was associated with development of t cell tumors in s ... | 1992 | 1316674 |
| incidence of localized feline leukemia virus infection in cats. | anecdotal descriptions of atypical felv infections, wherein standard clinical elisa or immunofluorescence testing fails to detect active infections, suggest that an unknown proportion of felv-infected cats may go undetected. in this study, 127 viremic and nonviremic cats experimentally inoculated with felv were evaluated at necropsy for atypical expression of felv antigen. results from viremic cats were in accordance with results of earlier studies on the pathogenesis of felv infection in cats, ... | 1992 | 1316726 |
| prevalence of feline immunodeficiency virus and other retroviral infections in sick cats in italy. | two hundred and seventy-seven sick pet cats living in italy were tested for antibodies to feline immunodeficiency virus (fiv) and for feline leukemia virus (felv) antigen. overall, 24% of the cats resulted positive for anti-fiv antibody and 18% for felv antigen. fiv was isolated from the peripheral mononuclear blood cells of ten out of 15 seropositive cats examined and from one out of eight saliva samples. no fiv isolations were obtained from six serum samples cultured. feline syncytium forming ... | 1992 | 1317073 |
| a survey of fiv antibodies and felv antigens in free-roaming cats in the capital area of finland. | feline immunodeficiency virus (fiv) was first isolated and identified in 1986. since then it has been shown to have a worldwide distribution, and the infection generally appears to have reached a state of endemicity. this is the 1st study of fiv-prevalence in finland. serum samples of 196 free-roaming cats were tested for antibodies to fiv and felv antigens (feline leukemia virus). with a combined enzyme-linked immunosorbent assay (elisa), 13 of the cats (6.6%) turned out to be positive for fiv ... | 1992 | 1317991 |
| development of a monoclonal antibody-based p24 capsid antigen detection assay for htlv-i, htlv-ii, and stlv-i infection. | a monoclonal antibody-based antigen capture enzyme-linked immunosorbent assay (elisa) was developed and employed to detect p24 capsid antigen from human t-cell lymphotropic viruses type i and ii (htlv-i, htlv-ii), simian t-cell lymphotropic virus type i (stlv-i)-infected cell lines, and from mononuclear cell cocultures of htlv-infected humans and stlv-i infected monkeys. a monoclonal antibody specific for htlv p24 and p53 capsid antigens was coated onto 96-well microtiter plates to capture htlv/ ... | 1992 | 1318063 |
| pathogenicity of feline leukemia virus is commonly associated with variant viruses. | many of the serious diseases resulting from feline leukemia virus (felv) infection are associated with the generation of novel variant viruses. the prototype felv-a virus is highly stable and circulates in the cat population without apparent antigenic change. however, recombination with cellular oncogenes produces viruses which cause leukemia or other malignant diseases. other recombinants within the env genes of felv-a and endogenous felv are recognized as belonging to a second subgroup, felv-b ... | 1992 | 1318467 |
| [trichomonad infections of the oral cavity in cats in south germany]. | in this investigation trichomonads were isolated from the oral cavity in 21 of 110 examined cats, and only from those which were simultaneously felv, fiv or fip positive. by means of scanning electron microscopy the trichomonads were shown to be round or piriform parasites which were on average 7.9 microns long and 6.2 microns wide at maximum width. they had 4 anterior flagella, which were on average 9.4 microns long, an undulating membrane measuring 6.7 microns with no trailing flagellum as wel ... | 1992 | 1319091 |
| viral inactivation in blood and red cell concentrates with benzoporphyrin derivative. | using both the vesicular stomatitis virus (vsv) and feline leukemia virus (felv) as models we have shown that the photosensitizer benzoporphyrin derivative ring a (bpd), when activated with red light (600-700 nm), is effective in eliminating both free virus and virally infected cells from spiked blood products and whole blood drawn from viremic cats experimentally infected with felv, under conditions which appear to share red blood cells. the effect of photodynamic therapy on infected lymphocyte ... | 1992 | 1319771 |
| the microepidemiology of wasting syndrome, a common link to diarrheal disease, cancer, rabies, animal models of aids, and hiv-aids yhaids). the feline leukemia virus and rabies virus models. | infant cats were inoculated intracranially with rabies or feline leukemia viruses in an experimental study of wasting syndrome. the daily pre- and postinoculation body weights were recorded until kittens were moribund. affected animals in both groups manifested growth failure or wasting syndrome. immunodepression, manifested by a conspicuous depletion of thymic cortex, the thymus dependent areas of the spleen, and growth hormone producing-alpha adenopituicytes was significantly (p less than 0.01 ... | 1992 | 1320842 |
| effects of tumor necrosis factor-alpha on normal feline hematopoietic progenitor cells. | the effects of tumor necrosis factor-alpha (tnf-alpha) on feline bone marrow hematopoietic progenitors were evaluated by exposing bone marrow mononuclear cells from specific pathogen-free cats to different concentrations of tnf-alpha (ranging from 50 to 800 pg/ml) for 2 h before plating for clonal assays of colony-forming units. tnf-alpha caused a dose-dependent suppression of feline erythroid colony-forming units (cfu-e) and erythroid burst-forming units (bfu-e), whereas granulocyte-macrophage ... | 1992 | 1321052 |