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the isolation of leishmania major from rodents in baringo district, kenya. 19846464123
vaccination against cutaneous leishmaniasis in mice using nonpathogenic cloned promastigotes of leishmania major and importance of route of injection.in vaccination studies, mice have been injected by different routes with living promastigotes of nonpathogenic leishmania followed by cutaneous challenge with pathogenic promastigotes. parasites used for vaccination have been promastigotes of the cloned parasite lines a12 and a52 derived from leishmania major isolate l137, or long-term cultured promastigotes of the leishmaniasis recidiva isolate, l32 (l.t.tropica). none of these protozoa causes lesions after cutaneous injection to mice. disease ...19846466205
an amphipathic sulphated glycoconjugate of leishmania: characterization with monoclonal antibodies.a major glycoconjugate of leishmania tropica major identified by two monoclonal antibodies was shown to be an externally oriented, amphipathic membrane antigen shed into the culture medium in which the parasites grow. this molecule could be labelled metabolically with [3h]glucose, [3h]galactose, [32p]phosphate and [35s]sulphate. it migrated as a polydisperse band upon electrophoresis in sds-polyacrylamide gels, spanning the region of the gel corresponding to an apparent mol. wt. of 20 000-67 000 ...19846499830
leishmania tropica: protective response in c3h mice vaccinated with excreted factor crosslinked with the synthetic adjuvant, muramyl dipeptide.excreted factor, an immunosuppressive, acidic polysaccharide released by promastigotes of leishmania tropica major in culture, was chemically crosslinked to the synthetic adjuvant muramyl dipeptide via the bifunctional imidoester dimethyladipimidate and poly-l-lysine. this conjugate, an uncrosslinked mixture of the components, or each of the components alone were injected one to three times into different groups of 8- to 12-week-old c3h mice. the mice were challenged 2 weeks after the last injec ...19846499996
antidepressants cause lethal disruption of membrane function in the human protozoan parasite leishmania.the antidepressant compounds clomipramine and nitroimipramine were cidal to extracellular promastigotes of both human protozoan parasites leishmania donovani and leishmania major. clomipramine also killed amastigotes of both species within murine macrophages with no apparent toxicity to the host cells. further, amastigotes were more sensitive than promastigotes to clomipramine. clomipramine (100 micromoles per liter or 0.2 nanomole per 1 x 10(6) cells) inhibited l-proline transport in promastigo ...19846505677
development of topical treatment for cutaneous leishmaniasis caused by leishmania major in experimental animals.topical treatment, with drug-containing ointments, of cutaneous leishmaniasis caused by leishmania major in balb/c mice was studied. twenty chemotherapeutic agents having potential or established antileishmanial activity were formulated in different ointment and cream bases. only 15% paromomycin sulfate with 12% methylbenzethonium chloride, 12% benzethonium chloride, 12% cetalkonium chloride, or 12% dimethyl sulfoxide, all incorporated in white soft paraffin (united kingdom patent application no ...19846517557
cutaneous leishmaniasis in kenya: transmission of leishmania major to man by the bite of a naturally infected phlebotomus duboscqi.one leishmanial stock was isolated from a phlebotomus duboscqi female captured in baringo district, kenya, and others from papular lesions that developed at sites where this sandfly had fed on a man. when characterized by cellulose acetate electrophoresis (eight enzymes examined), these isolates proved to be identical to known leishmania major strains from man and a rodent (arvicanthis sp.) and different from l. donovani and l. adleri, which also occur in baringo. this is the first case of human ...19846533846
comparison of the effect of various stimuli on the leishmaniacidal capacity of human monocytes in vitro.leishmania organisms are obligate intracellular parasites of mammalian mononuclear phagocytes in vivo. in order to study the interactions of these parasites and mononuclear phagocytes, we have used a model of infection of leishmania major in human monocytes in vitro. the presence of intracellular parasites did not alter the normal secretion of lysozyme or result in increased secretion of prostaglandin e2 (pge2) or superoxide anion by the monocytes. addition of concanavalin a (con a), which binds ...19846589101
mechanisms of acquired immunity in leishmaniasis.self-curing cutaneous leishmaniasis depends on t cell-mediated immune activation of infected macrophages. failure of immune control in inbred mouse models of metastasizing mucocutaneous and visceralizing forms of the disease involves, respectively, insusceptibility of the parasite and the generation of t cells that suppress a potentially curative response. prophylactic immunization in man has so far been restricted to cutaneous leishmaniasis and based on inducing infection under controlled condi ...19846151691
restriction endonuclease analysis of leishmania kinetoplast dna characterizes parasites responsible for visceral and cutaneous disease.the kinetoplast dna (kdna) from promastigotes of leishmania responsible for old and new world cutaneous and visceral disease was characterized to determine if species and strains causing similar or different diseases could be identified. restriction enzymes were used to digest kdna into fragments that were separated into characteristic banding patterns after electrophoresis in agarose or linear gradient polyacrylamide gels. hybridization was conducted with a 32p-kdna probe and kdna fragments tra ...19846091469
induction by specific t lymphocytes of intracellular destruction of leishmania major in infected murine macrophages.the following cell populations derived from lymph nodes of mice primed in vivo with living leishmania major promastigotes were tested for their capacity to induce parasiticidal activity in l. major-infected macrophages: a l. major-primed lymph node cells, draining lymph node cells from mice primed by a subcutaneous injection of living l. major in freund's complete adjuvant; b l. major-specific t blasts, i.e. blast t cells resulting from in vitro challenge of primed lymph node cells with l. major ...19846609335
leishmania major: culture media, mouse strains, and promastigote virulence and infectivity.promastigotes of leishmania major were isolated from an infected mouse in two media, blood agar and schneider's medium + 30% fetal calf serum, and maintained continuously for over 1 year. infectivity studies in two strains of mice, outbred cd1 strain and inbred balb/c strain, showed that promastigotes grown in schneider's medium maintained infectivity to balb/c mice throughout the period of cultivation. infectivity to cd1 strain mice was progressively lost. promastigotes grown in blood agar medi ...19846723897
mechanical transmission of leishmania major by glossina morsitans morsitans (diptera: glossinidae). 19846726762
[comparative electron microscopy study of leishmania major and l. tropica in experimental infestation of the sandfly phlebotomus papatasi].for the first time comparative study was conducted of the ultrastructure of promastigotes of leishmania major and l. tropica in the organism of phlebotomus papatasi which for the first species of leishmania is and for the second species is not a natural invertebrate host. during the bloodsucking on mesocricetus auratus experimentally infected with leishmania sandflies perceive amastigotes of both l. major and l. tropica. in the midgut of the sandfly both species of leishmania pass into the stage ...19846728513
[interepidemic surveillance of a cutaneous leishmaniasis focus in senegal].the cutaneous leishmaniasis is rampant in an endemo -epidemic way in the region of thiès, senegal. at the occasion of an epidemic observed between 1975 and 1978, the ecological study of the focus of keur moussa , led by dedet and al., permitted to discover, for the first time in west africa, the structure of a cutaneous leishmaniasis focus. the most important part of the present laboratory work consists in the observation of that wild anthropozoonosis due to leishmania tropica major, having as v ...19846738336
leishmania major: identification of stage-specific antigens and antigens shared by promastigotes and amastigotes.a battery of antisera to leishmania major was used to identify stage-specific antigens, or antigens expressed predominantly in amastigotes or promastigotes. at least 30 protein antigens common to amastigotes and promastigotes could be detected in 35s-methionine labelled preparations. they ranged in molecular weight from 25 000 to 165 000. two amastigote specific antigens and five antigens expressed predominantly in the amastigote were detected in biosynthetically-labelled preparations. five prom ...19846739119
immunogenic proteins of leishmania major during mouse infection.mice of different strains (c3h/he, a/jax, dba/2, balb/c and cba/ca) were infected intracutaneously with leishmania major. antibody production was analysed on the antigens of the promastigote form of the parasite which had previously been separated by sds-polyacrylamide gel electrophoresis and transferred to nitrocellulose sheets. the kinetics of igg antibody production were determined and the major immunogenic proteins of the parasite were identified for each strain of mouse. it was found that: ...19846739122
brazilian leishmania stocks phenotypically similar to leishmania major.screening by enzyme electrophoresis of isolates of new world leishmania from different geographic areas revealed a number of stocks with enzyme profiles different from those produced by reference strains of described subspecies of l. mexicana, l. braziliensis, and l. donovani. analysis by six enzymes (aspartate aminotransferase; alanine aminotransferase; malate dehydrogenase; glucose-6-phosphate dehydrogenase; phosphoglucomutase; and glucose-phosphate isomerase) showed that these stocks have ide ...19853834794
stimulation of trypanosoma brucei pyruvate kinase by fructose 2,6-bisphosphate.the activity of pyruvate kinase present in a crude extract of the bloodstream form of trypanosoma brucei was greatly increased by fructose 2,6-bisphosphate, which converted the saturation curve for phosphoenolpyruvate from a sigmoid into a hyperbola with no change in v. phosphate and arsenate had an effect opposite to that of fructose 2,6-bisphosphate and the apparent ka for fructose 2,6-bisphosphate was shifted from 75 nm to 1.5 microm by the presence of 5 mm phosphate. fructose 1,6-bisphosphat ...19853841061
immunization with leishmania receptor for macrophages protects mice against cutaneous leishmaniasis.the leishmania major receptor for macrophages is a lipid-containing glycoconjugate that is recognized by the monoclonal antibody wic-79.3. when l. major promastigotes were incubated with fab fragments of wic-79.3 prior to injection into genetically susceptible mice, their infectivity was decreased. fab fragments from an irrelevant control antibody of the same class had no effect. the l. major glycolipid was purified from detergent-solubilized promastigotes by affinity chromatography on immobiliz ...19853862105
human monocytes infected with leishmania amastigotes enhance lymphocyte proliferation.human monocytes were infected in vitro with leishmania tropica major (l. major) promastigotes which transformed to intracellular amastigotes. a spontaneous increase in lymphocyte proliferation occurred in mononuclear cell cultures where the monocytes had been infected with l. major organisms. in addition, an apparent additive effect of lymphocyte proliferation was seen in cultures infected with l. major following phytohaemagglutinin stimulation. this effect was apparent after 3 days in culture a ...19853874731
a limiting dilution assay for quantifying leishmania major in tissues of infected mice.a limiting dilution assay for the quantification of leishmania major in infected mouse tissue was developed. the assay was found to be both sensitive and reliable, and, due to its design, could be scored either visually or following the incorporation of 3h-thymidine by the growing parasites. results are presented in which the assay was employed to enumerate l. major in the tissues of susceptible (balb/c) and resistant (cba) mice at intervals after infection with l. major. it was found that paras ...19853877902
the development of a solid phase radioimmunoassay for the detection of leishmanial parasites in the sand fly.the development of a solid phase radioimmunoassay inhibition test using anti-leishmanial monoclonal antibodies is described for the detection of leishmanial promastigote infections in sand flies, as an aid to epidemiology. as few as 6-12 leishmania major promastigotes could be detected in laboratory-bred phlebotomus papatasi. the test was sensitive and species-specific.19853885771
leishmania amastigotes: resistance to complement-mediated lysis is not due to a failure to fix c3.amastigote forms of leishmania major are sensitive to lysis by fresh serum, whereas those of l. donovani are resistant. to understand the basis for this resistance we have examined the interaction of complement with amastigotes of seven strains of leishmania. complement activation was determined by measuring the ability of amastigotes to consume complement from normal serum and by identifying parasite surface-bound c3. all of the strains that were tested activated complement, including both thos ...19853886796
nitrocellulose-based assays for the detection of glycolipids and other antigens: mechanism of binding to nitrocellulose.a variety of simple and rapid assays for the detection of glycolipids by direct binding to nitrocellulose or binding to antibody-coated nitrocellulose, and probing with monoclonal antibodies are described. these include dot-blotting, charge shift electrophoresis and electroblotting. it is shown that the direct binding of the leishmania major glycolipid to nitrocellulose is dependent on its lipid moiety, indicating that the mechanism of binding is probably via hydrophobic interactions. however, t ...19853902968
immunoregulatory pathways in murine leishmaniasis: different regulatory control during leishmania mexicana mexicana and leishmania major infections.the effect of whole body sublethal gamma irradiation on the subsequent growth of leishmania mexicana mexicana and leishmania major was studied in cba/ca and balb/c mice. whereas balb/c mice are highly susceptible to both parasites developing non healing progressively growing lesions at the site of cutaneous infection, cba/ca mice develop small healing cutaneous ulcers following subcutaneous infection with l. major but non healing lesions following subcutaneous infection with l.m. mexicana. prior ...19853907906
phenotypic diversity of cloned lines of leishmania major promastigotes.in vitro cultured promastigotes of virulent (v) and avirulent (a) cloned lines of leishmania major, and the parental isolate lrc-l137, were examined with respect to morphology, cell size, growth rate, and apparent dna content. growth rates of all lines were comparable and both virulent (v121, lrc-l137) and avirulent parasites (a12, a52, a59) exhibited a progressive decrease in apparent dna content with time in culture, as measured by incorporation of hoechst dye 33342. the four cloned lines and ...19853922149
macrophage activation to kill leishmania major: activation of macrophages for intracellular destruction of amastigotes can be induced by both recombinant interferon-gamma and non-interferon lymphokines.macrophages treated with lymphokine (lk)-rich culture fluids from antigen- or mitogen-stimulated spleen cells or the hybridoma t cell 24/g1, or murine recombinant interferon-gamma (ifn-gamma) from either transfected monkey kidney cells (cos rifn-gamma) or bacterial (e. coli) dna (rifn-gamma) developed the capacity to kill intracellular amastigotes of leishmania major. removal of ifn activity from lk by neutralizing fluid phase monoclonal anti-rifn-gamma antibody, or by solid phase immunoadsorpti ...19853930606
[efficacy of the vaccination of c57bl/6 mice against infection with different species of leishmania].antigens were isolated from lysates of promastigotes of leishmania infantum by electro-elution from polyacrylamide gels. antigens with respective molecular weights for f2 = 94-67 kd; f5 = 30-20 kd and f6 below 20 kd, were injected intravenously in c 57 bl/6 mice. the immune sera were studied by indirect immunofluorescence; an in vivo test showed their inhibitory effect on the life cycle of several leishmania species from the old and the new world. furthermore, mice immunized with f2, f5 or f6 we ...19853936605
cell contact-mediated macrophage activation for antileishmanial defence: mapping of the genetic restriction to the i region of the mhc.employing a murine model of cutaneous leishmaniasis, we observed that draining popliteal lymph node lyt-1+2- t cells from c57bl/6 mice with leishmania major (also called l. tropica major) footpad infections activate macrophages in vitro to kill intracellular leishmania amastigotes. this antileishmanial effect requires direct contact between t cell effectors and infected macrophage targets. furthermore, it neither is strictly lymphokine mediated nor causes damage to infected macrophages; and it i ...19853936653
leishmania major: excreted factor, calcium ions, and the survival of amastigotes.mouse macrophages infected with amastigotes of leishmania major contain about 40% more intracellular exchangeable calcium than control macrophages. similar elevation of intracellular exchangeable calcium was observed in macrophages engulfing red blood cells coated with purified excreted factor from l. major. the rate of cytolysis of red blood cells coated with excreted factor was significantly lower than that of uncoated controls. excreted factor strongly binds calcium; thus, the possible role o ...19853972056
macrophage activation for microbicidal activity against leishmania major: inhibition of lymphokine activation by phosphatidylcholine-phosphatidylserine liposomes.resident peritoneal macrophages from untreated mice develop microbicidal activity against amastigotes of the protozoan parasite leishmania tropica (current nomenclature = leishmania major) after in vitro exposure to lk from antigen-stimulated leukocyte culture fluids. this lk-induced macrophage microbicidal activity was completely abrogated by addition of 7:3 phosphatidylcholine: phosphatidylserine liposomes. liposome inhibition was not due to direct toxic effects against the parasite or macroph ...19853980997
mycoses, bacterial infections and antibacterial activity in sandflies (psychodidae) and their possible role in the transmission of leishmaniasis.high incidence of mycoses were found in the guts and malpighian tubes of phlebotomus papatasi from the jordan valley and p. tobbi from zakinthos, greece. infections with several different bacteria were also found in the guts of female p. tobbi. fungi cultured from guts of laboratory reared p. papatasi that had similar mycoses were identified as aspergillus sclerotiorum and saccharomyces cerevisiae. fungi-infected laboratory reared p. papatasi were refractory to artificial infections with a leish ...19853982854
modification of sand fly biting behavior by leishmania leads to increased parasite transmission.to attempt rodent-sand fly-rodent transmission of leishmania major, laboratory-reared phlebotomus doboscqi were fed on l. major-infected mice and then refed on uninfected mice 21 days later. flies which refed either probed 1-2 times and took a full blood meal in less than 10 min or probed 3 or more times and took little or no blood during a period of 15 min or more. when dissected, 7 of 8 flies which experienced difficulty in obtaining a blood meal had flagellates in their cibaria, an observatio ...19853985271
[presence of leishmania major yakimoff and schokhor, 1914 in mali. enzymatic identification of a strain of human origin].the first case of oriental sore reported to leishmania major is identified in mali. the characterization of the stain isolated from a left arm lesion of a 30 years old european woman is carried out by electrophoretic analysis using enzymes, i.e. pgm, pgi, g-6-pdh, 6-pgdh, idh, mdh, me, got.19853985536
evidence that the major surface proteins of three leishmania species are structurally related.promastigotes of leishmania major lrc-l137, l. donovani lem 75, and l. tropica lrc-l32 were surface radioiodinated. the proteins of the parasites were analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and labeled molecules were revealed by fluorography. a single major iodinated protein of mr 63 000 (p63) was identified in each of the three species. these proteins were partially purified by phase separation in triton x-114 solution, demonstrating that the p63 of each of the th ...19853990704
is leishmania major the cause of infantile kala-azar in alexandria, egypt? 19853992633
an h-11-linked gene has a parallel effect on leishmania major and l. donovani infections in mice.the courses of visceral infection following intravenous injection of leishmania donovani amastigotes, or lesion growth following subcutaneous injection of l. major promastigotes, were examined in b10.129(10m) (h-2b, h-11b) mice and compared with disease profiles observed in congenic c57bl/10scsn(= b10) (h-2b, h-11a) and b10.d2/n (h-2d, h-11a) mice, and in balb/mice. possession of alternative alleles at h-11 and closely linked loci transformed the normal curing/healing phenotype of b10 mice into ...19853997209
complement-mediated serum cytotoxicity for leishmania major amastigotes: killing by serum deficient in early components of the membrane attack complex.leishmania major, the agent of oriental sore, is an obligate intracellular parasite of macrophages in mammalian hosts. man's immune defense against this organism requires participation of specifically sensitized lymphocytes and activated macrophages. recent studies, however, have demonstrated that as little as 1/120 concentration of normal human serum is highly cytotoxic for the amastigote form of l. major. initiation of the lethal process occurs rapidly, requiring only 30 sec of parasite exposu ...19853998474
zoonotic cutaneous leishmaniasis in saudi arabia: the incrimination of phlebotomus papatasi as the vector in the al-hassa oasis.surveys of the phlebotomine fauna in a focus of zoonotic cutaneous leishmaniasis (zcl) in the al-hassa oasis, eastern province, saudi arabia, revealed only one species of phlebotomus (p. papatasi) and three of sergentomyia (s. antennata, s. clydei and s. fallax). 11 specimens of p. papatasi from six sites in the oasis were found with promastigotes in the midgut. an isolate from one of the sandflies was typed by the examination of isoenzymes and identified as leishmania major, zymodeme lon-4 (= m ...19854002297
lipid and lipopolysaccharide-like antigens of leishmania promastigotes.extraction of whole promastigotes of leishmania tropica major and l. donovani with a mixture of hexane and isopropanol (3:2) yielded three fractions containing immunological activity: lipids, where the activity was determined by radioimmunoassay; a lipopolysaccharide-like (lps-like), water-soluble precipitate, where activity was determined both by radioimmunoassay and double gel diffusion, and the phenol: water extract of the lipid-free promastigotes, where activity was followed by double gel di ...19854009512
impaired macrophage leishmanicidal activity at cutaneous temperature.temperature is one of the primary influences upon the pathogenesis of cutaneous leishmaniasis. in this study, we measured the temperature of murine leishmanial lesions and determined the ability of lymphokine (lk) activated macrophages to kill leishmania major at these temperatures. the temperature of leishmanial lesions in balb/c and c3h/hen mice ranged from 27 degrees c to 32 degrees c. we found that lk activated resident or inflammatory macrophages exhibited significantly less leishmanicidal ...19854011301
the molecular karyotype of leishmania major and mapping of alpha and beta tubulin gene families to multiple unlinked chromosomal loci.the arrangement of tubulin genes in the genome of the protozoan parasite leishmania major was studied by genomic southern blot analysis and mapping of genes to chromosomes fractionated by pulsed field gradient gel (pfg) electrophoresis. alpha-tubulin genes exist as a tandem array of 2.4 kb psti fragments. beta-tubulin genes are found as a tandem array of 3.9 kb avai or pvui fragments, but additional genes are also found on other genomic dna fragments. chromosome-sized dna molecules released from ...19854011445
heat shock genes: regulatory role for differentiation in parasitic protozoa.the parasitic protozoa trypanosoma brucei and leishmania major are transmitted by insect vectors to their mammalian hosts. the temperature difference between the hosts (25 degrees and 37 degrees c) may induce a heat shock response in the parasite. transcripts of heat shock genes (homologous to hsp70 and hsp83) were 25 to 100 times more abundant in trypanosoma brucei bloodstream forms (trypomastigotes) than in insect (procyclic) stages. in leishmania major the patterns of heat shock gene expressi ...19854012301
the leishmania receptor for macrophages is a lipid-containing glycoconjugate.the glycoconjugate of leishmania major recognized by the monoclonal antibody wic-79.3 exists in two forms. the cellular form associated with the promastigote is a population of amphipathic molecules consistent with membrane insertion. in contrast, the extracellular form mainly consists of hydrophilic molecules, and probably arises by cleavage of the cellular form by an endogenous phospholipase. the hydrophilic population of extracellular glycoconjugate molecules binds specifically to macrophages ...19854018028
prophylactic immunization against experimental leishmaniasis. iv. subcutaneous immunization prevents the induction of protective immunity against fatal leishmania major infection.durable immunity against fatal l. major infection in genetically susceptible mice can be induced by immunization with 150,000-rad irradiated or heat-killed promastigotes administered i.v. or to a lesser extent i.p. conversely, subcutaneous (s.c.) and intramuscular (i.m.) injections are not only totally ineffective but generally increase susceptibility to and enhance the progression of the disease, leading to earlier mortality. this detrimental effect is particularly evident with lower infecting ...19854020140
development of infective stage leishmania promastigotes within phlebotomine sand flies.midgut promastigotes were obtained from phlebotomus papatasi and lutzomyia longipalpis on days 3-7 after infection with cloned isolates of leishmania major and leishmania mexicana amazonensis, respectively, and examined as to their ability to initiate cutaneous infections in balb/c mice. sequential development of midgut promastigotes from a noninfective to an infective stage was confirmed for both the new world and old world species. the generation of infective promastigotes from rapidly dividin ...19854039899
zoonotic cutaneous leishmaniasis in saudi arabia: lesions healing naturally in man followed by a second infection with the same zymodeme of leishmania major.a patient with a previous history of an infection with leishmania b. braziliensis contracted zoonotic cutaneous leishmaniasis (zcl) in the al-hassa oasis, eastern province, saudi arabia. five lesions healed spontaneously over a period of 40 weeks without treatment. a year after acquiring zcl he became infected again in the same focus. isolates of parasites at both episodes were identified as l. major, zymodeme lon-4. compared with the first infection of zcl, parasites were fewer in the lesions o ...19854041081
immunoprophylaxis in balb/c mice: a model for development of protection against primary and secondary infection with leishmania major. 19854042672
genetic control of systemic leishmania major infection: identification of subline differences for susceptibility to disease. 19854042673
[study of the virulence and immunogenicity of vaccinal strains of leishmania major, preserved by freezing in liquid nitrogen]. 19854050086
genetic control of systemic leishmania major infections: dissociation of intrahepatic amastigote replication from control by the lsh gene.systemic disease induced by leishmania major was estimated by microscopic examination of liver impression smears and determination of numbers of intrahepatic amastigotes in intravenously or subcutaneously infected inbred, hybrid, and congenic mice. the distribution of susceptible phenotypes among these mice, particularly the susceptibility of a strain congenic for lshr, strongly suggested that lsh, a gene which controls intrahepatic replication of leishmania donovani, does not influence systemic ...19854055035
identification and purification of membrane and soluble forms of the major surface protein of leishmania promastigotes.a major integral membrane glycoprotein of 63 kda (p63), present at 500,000 copies/cell, was found on the surface of leishmania major lem 513 promastigotes. this protein was labeled either by surface iodination of the cells or by metabolic incorporation of [35s]methionine. peptide maps of the proteins labeled by the two procedures were identical. protein p63 was purified in three steps: extraction and phase separation in the nonionic detergent triton x-114, chromatography on deae-cellulose, and f ...19854066680
rapid enzymological identification of leishmanial isolates in kenya.leishmanial isolates from kenya were identified as being either leishmania major, l. donovani or l. aethiopica by using cellulose acetate electrophoresis. species determination is based on the electrophoretic pattern for glucose phosphate isomerase alone. this report describes the technique and presents data on its reliability as a rapid identification test for leishmania isolates from the same geographical region.19854082254
induction and detection of leishmanial infections in rattus norvegicus.weanling sprague-dawley rats were injected intradermally with leishmania major or with l. donovani promastigotes. parasites could be cultivated from the skin at times from 2 to 28 days after infection. at necropsy, no parasites were observed in spleen or liver impression smears, nor could they be cultivated from heart blood or spleen, even when skin cultures were positive. rats were not highly susceptible to infection with l. donovani, since parasites could be cultured from skin only at 2 days a ...19854082256
examination of variables in the vaccination of mice against cutaneous leishmaniasis using living avirulent cloned lines and killed promastigotes of leishmania major. 19854093239
pathogenesis of leishmania major in guinea pig. 19854093657
keziot--a new endemic site of cutaneous leishmaniasis in israel. an epidemiological and clinical study of a non-immune population entering an endemic area.in this study we describe a new endemic focus of cutaneous leishmaniasis at keziot in southern israel, and the pattern of the disease among a group of soldiers newly based in the area. interviews and physical examinations were conducted on 296 soldiers, and 247 were subjected to a leishmanin skin test. positive tests were recorded in 18% of the soldiers; in 16% of them keziot was identified as the area where the infection was acquired. positive skin tests were found among 93% and 41% of soldiers ...19854095766
identification of cell surface carbohydrate and antigenic changes between noninfective and infective developmental stages of leishmania major promastigotes.differentiation of leishmania major promastigotes from a noninfective to an infective stage has been demonstrated for promastigotes growing within axenic culture and within the sandfly vector. we have been attempting to identify specific biochemical or antigenic changes that are associated with the development of infective-stage promastigotes. in this report we demonstrate that during growth, cultured l. major promastigotes undergo selective changes in surface carbohydrates, determined by their ...19852582050
antigen recognition by effector t cells in antileishmanial defense.we have observed that t cells (ly1+2-) from draining lymph nodes of mice that have footpad infections with leishmania major activate macrophages for antileishmanial effects in vitro in an apparently contact-dependent, noncytotoxic manner. the nature of antigenic specificity in this system was investigated. whereas lymphocytes sensitized to l. major induced antileishmanial effects in macrophages infected with l. major, lymphocytes sensitized to listeria monocytogenes were ineffective. when macrop ...19852413143
specific suppressor t cells for delayed-type hypersensitivity in susceptible mice immunized against cutaneous leishmaniasis.balb/c mice injected intravenously with 10(6) or higher doses of formaldehyde-fixed promastigotes (ffp) of leishmania major developed significantly lower levels of delayed-type hypersensitivity (dth) compared with uninjected control mice when they were subsequently immunized intradermally with ffp. the suppression of dth was antigen specific and was also inducible with lethally irradiated promastigotes or soluble parasite antigens. the suppressive effect was adoptively transferable with splenic ...19853160663
prophylactic immunization against experimental leishmaniasis. v. mechanism of the anti-protective blocking effect induced by subcutaneous immunization against leishmania major infection.the responsiveness of balb/c mice to protective i.v. immunization with 150,000-rad irradiated or heat-killed leishmania major promastigotes can be totally suppressed by prior subcutaneous (s.c.) injection of the same "vaccine." induction of this effect is leishmania specific for although prevention of protection against l. major infection can be obtained with either homologous or leishmania donovani promastigotes, it does not follow s.c. administration of an immunogenic trypanosoma cruzi epimast ...19853160786
the mouse macrophage receptor for c3bi (cr3) is a major mechanism in the phagocytosis of leishmania promastigotes.we examined the role of the macrophage receptor for c3bi, the cr3, in the phagocytosis of leishmania major promastigotes and report that m1/70, a monoclonal antibody to the cr3, inhibited the binding of leishmania to macrophages both when the assays were performed in the presence of normal serum and in its absence. in serum, leishmania activate complement and fix c3. fixation and subsequent cleavage to c3bi occurs rapidly, and by as early as 5 min both forms of the molecule can be identified on ...19853161950
higher frequency of leishmania major-specific l3t4+ t cells in susceptible balb/c as compared with resistant cba mice.in previous studies, we reported that a) the adoptive transfer of parasite-specific l3t4+ t cells enhanced rather than inhibited the development of lesions induced by leishmania major in normal balb/c mice, and b) the depletion in vivo of l3t4+ t cells by administration of anti-l3t4 monoclonal antibody reversed the susceptibility of balb/c mice to l. major. to further assess the role of specific l3t4+ t cells in the development of lesions induced by l. major in balb/c mice, the frequency of para ...19862418115
the glycoconjugate derived from a leishmania major receptor for macrophages is a suppressogenic, disease-promoting antigen in murine cutaneous leishmaniasis.lymphoid cells from genetically-susceptible balb/c mice immunized against a glycoconjugate of the protozoan parasite, leishmania major, promote chronic cutaneous disease in balb/c nude mice. this cell population therefore differs from cells harvested from non-immunized balb/c mice that are known to be potent mediators of protection against cutaneous leishmaniasis in minimally-reconstituted, syngeneic nude mice. the glycoconjugate when injected into genetically-resistant c57bl/6 mice will increas ...19862425330
suppression of pathogenesis in cutaneous leishmaniasis by uv irradiation.the effects of suberythematous levels of uv-b radiation on the development of of cutaneous leishmaniasis were studied in b10.129(10m) mice. doses of 15 mj cm-2 uv-b applied locally to the injection site suppressed the development of skin lesions after the inoculation of leishmania major promastigotes. the primary targets of uv-b radiation appeared to be host cells and not leishmanial parasites, because uv-b irradiation of parasites cultured in vitro did not affect their viability, but did kill h ...19863949383
prophylactic treatment of balb/c mice with cyclosporine a and its analog b-5-49 enhances resistance to leishmania major.the effect of cyclosporine a (cs a) and its analog b-5-49 on leishmania major in vitro and in vivo in the highly susceptible balb/c mouse strain has been investigated. in vitro, both of these drugs showed significant toxicity toward l. major, but only at relatively high levels (greater than 25 micrograms/ml). however, at 5 and 10 micrograms/ml, levels which correspond more closely to physiologically achievable concentrations, no growth-inhibitory effect in vitro was observed. on administration o ...19863958489
characterization of kenyan leishmania spp. and identification of mastomys natalensis, taterillus emini and aethomys kaiseri as new hosts of leishmania major.a survey to examine rodents for leishmanias was initiated in the perkerra settlement scheme, marigat, baringo district, kenya, 789 rodents of ten different species were trapped and examined. leishmanial parasites were isolated from the spleen and liver of 17 animals of five different species: seven from tatera robusta, five from arvicanthis niloticus, two from mastomys natalensis, two from taterillus emini and one from aethomys kaiseri. these were identified as l. major by enzyme electrophoresis ...19863632097
primary structure of the gene encoding the bifunctional dihydrofolate reductase-thymidylate synthase of leishmania major.we have determined the nucleotide sequence of the dihydrofolate reductase-thymidylate synthetase (dhfr-ts) gene of the protozoan parasite leishmania major (dihydrofolate reductase, ec 1.5.1.3 and thymidylate synthase, ec 2.1.1.45). the dhfr-ts protein is encoded by a single 1560-base-pair open reading frame within genomic dna, in contrast to vertebrate dhfrs or mouse and phage t4 tss, which contain intervening sequences. comparisons of the dhfr-ts sequence with dhfr and ts sequences of other org ...19863458220
the effects of con a-induced lymphokines from the t-lymphocyte subpopulations on human monocyte leishmanicidal capacity and h2o2 production.the effects of concanavilin a (con a)-induced lymphokines from human peripheral blood mononuclear cells, enriched helper and suppressor lymphocyte populations and recombinant interferon-gamma (ifn-gamma) on the ability of monocytes to promote killing of intracellular leishmania major (l. major) amastigotes and to induce the production of hydrogen peroxide (h2o2) was examined. all these mitogen-induced supernatants contained active ifn-gamma. there were no differences in the ability of these supe ...19862945777
b lymphocytes are required for the generation of t cells that mediate healing of cutaneous leishmaniasis.the role that b lymphocytes and/or antibodies play in the healing of leishmania major infections in genetically resistant c3h/hen mice was investigated by monitoring the course of infection in animals that had been b cell depleted by treatment from birth with anti-igm sera (mu-suppressed). l. major infection of mu-suppressed c3h/hen mice produced lesions that were significantly larger than those induced in control animals, and failed to heal. moreover, vaccinated mu-suppressed mice also develope ...19863487581
increased myelopoiesis during leishmania major infection in mice: generation of 'safe targets', a possible way to evade the effector immune mechanism.balb/c mice are highly susceptible to leishmania major infection and develop a disseminated lethal disease. previous experiments indicate that during infection the spleen is heavily populated with large mononuclear cells containing amastigotes. morphologically these cells resemble undifferentiated monocytes and granulocytes. in this study we examined myelopoiesis in balb/c and c57bl/6 (resistant) mice during infection with l. major. the number of macrophage-granulocyte precursors in the spleen o ...19863488146
suppression of interleukin-2 production by macrophages in genetically susceptible mice infected with leishmania major.spleen cells from balb/c mice infected with 2 x 10(7) l. major promastigotes and developing progressive disease produced significantly lower levels of interleukin-2 (il-2) in response to concanavalin a stimulation than did spleen cells from uninfected mice. in contrast, spleen cells from sublethally irradiated and infected mice, which were able to contain lesion development, produced significantly higher levels of il-2. the increase in il-2 production closely paralleled lesion regression. mice p ...19863490440
effect of t-lymphocyte suppression on the parasite burden in leishmania major-infected, genetically susceptible balb/c mice.treatment of leishmania major-infected, genetically susceptible balb/c mice with the t-lymphocyte-immunosuppressive drug cyclosporin a (cya) resulted in a significantly reduced parasite burden in the local site of infection and in the draining lymph nodes. these data indicate that t cells are pivotal for the propagation of l. major in vivo.19863491051
occurrence of autoantibodies to intermediate filament proteins in human visceral leishmaniasis and their induction by experimental polyclonal b-cell activation.fifteen sera of patients with visceral leishmaniasis were investigated for the occurrence of autoantibodies. they were found in high incidence and titre, and with specificity to the intermediate filament (infil) proteins vimentin (12 out of 15 with a titre higher than 1:10) and keratin (9 out of 15 with a titre higher than 1:10) as well as to speckled anti-nuclear antigens (ana). additionally, supernatants of leishmania major and leishmania donovani cultures containing soluble parasite-derived a ...19863492440
murine cutaneous leishmaniasis: resistance correlates with the capacity to generate interferon-gamma in response to leishmania antigens in vitro.the kinetics of cell-mediated immunity developed during the course of leishmania major infection in resistant (c57bl/6) and susceptible (balb/c) mice were determined by using in vitro bioassays. cells isolated from the lymph nodes draining the infected footpads were assayed for their proliferative responses to leishmania antigens (promastigote and amastigote) or to concanavalin a (con a). although lymph node cells (lnc) from both mouse strains proliferated to mitogen and antigen early after infe ...19863079789
the enhancing effect of interferon-beta and -gamma on the killing of leishmania tropica major in human mononuclear phagocytes in vitro.both native human ifn-beta or -gamma added to human monocytes in culture increased their leishmaniacidal effect on intracellular leishmania tropica major (l. major) amastigotes. this effect was dose-dependent, and was apparent if the ifn was added either before or after infection of the monocyte cultures with the promastigote form of the parasite. compared on the basis of antiviral activity, ifn-gamma was shown to have a leishmaniacidal effect approximately three times greater than ifn-beta. rec ...19863082979
identification of a genetic locus, rsm-1, controlling protective immunity against schistosoma mansoni.mice of most inbred strains develop moderate to high levels of resistance to challenge infection on vaccination with radiation-attenuated cercariae of schistosoma mansoni. p strain mice, however, fail to display significant protective immunity after exposure to the same vaccine. to examine the genetic basis of this polymorphism in host immunity, vaccine-induced resistance was examined in (c57/bl6j x p/n)f1, f2, and reciprocal backcross generations. the defective immunity which characterizes the ...19863091695
failure of meglumine antimoniate to cure cutaneous lesions due to leishmania major in algeria. 19863544363
pathophysiology of experimental leishmaniasis: pattern of development of metastatic disease in the susceptible host.a clear understanding of the etiology of the various forms of leishmaniasis will require knowledge of how physiological properties of the parasite and host immunity influence the pattern of development of the disease. of particular importance are how these factors affect the growth rate of leishmania spp. at the site of inoculation in the skin, their capacity to disseminate to visceral and distant cutaneous sites, and their capacity to multiply once there. this paper details the pattern of devel ...19863699885
the major surface protein of leishmania promastigotes is anchored in the membrane by a myristic acid-labeled phospholipid.promastigotes of the protozoan parasite leishmania major were biosynthetically labeled with myristic acid. solubilization and phase separation in the non-ionic detergent triton x-114 shows that the label is not incorporated into soluble hydrophilic proteins, but is incorporated into a few insoluble proteins. the bulk of the incorporated fatty acid is associated with a heterogeneous phosphorylated glycolipid and a few amphiphilic integral membrane proteins. among these, the major surface protein ...19863709520
leishmania major: solid phase radioimmunoassay for antibody detection in human cutaneous leishmaniasis.a radioimmunoassay for the quantitative determination of antileishmanial antibody in sera from patients suffering from cutaneous leishmaniasis was developed. the assay, using as antigen either the soluble fraction from freeze-thawed sonicated leishmania major (lrc-l137) promastigotes or a carbohydrate-lipid containing fraction obtained by extraction with hexane-isopropanol, was shown to be sensitive and reproducible. the sera of 95 patients were examined. these were from patients with cutaneous ...19863720902
impaired drug uptake in methotrexate resistant crithidia fasciculata without changes in dihydrofolate reductase activity or gene amplification.crithidia fasciculata cells grown in defined medium are sensitive to methotrexate (mtx), an inhibitor of dihydrofolate reductase (dhfr). when cells are challenged with 2-5 microm mtx, cell division ceases after 3-4 divisions and the cells become rounded and immotile for approximately 60 h, with a 40% decrease in cell viability occurring during this period. the cells then recover normal morphology and cell division resumes. cells which undergo this treatment can be transferred directly into high ...19863724795
stable amplified dna in drug-resistant leishmania exists as extrachromosomal circles.the relative stability of amplified dna in drug-resistant leishmania major was previously reported to be dependent on location, that is, unstable amplified dna was extrachromosomal and stable amplified dna was chromosomal. leishmanial chromosomes have now been directly examined by means of orthogonal-field-alternation gel electrophoresis (ofage). the amplified dna's in three resistant cell lines displayed unusual migration and were clearly extrachromosomal, regardless of whether the amplified dn ...19863726545
leishmania in the old world: 1. the geographical and hostal distribution of l. major zymodemes.135 stocks of leishmania major from man, reservoir hosts and sandflies were characterized using thin-layer starch-gel electrophoresis of 13 enzymes: mdh, 6pgd, gd, sod, asat, alat, pk, pgm, es, nh, pepd, mpi, gpi. homogeneity in this species was demonstrated by identical electrophoretic mobilities in nine enzymes. polymorphism in four enzymes: 6pgd, gpi, pepd, es, gave six zymodemes among the collection. stocks from sandflies and several species of burrowing rodents were indistinguishable from t ...19863727004
[isolation of leishmania major yakimoff and shokhor, 1914 (kinetoplastida-trypanosomatidae) in meriones shawi-shawi (duvernoy, 1842) (rodentia-gerbillidae) in tunisia].leishmania major, agent of zoonotic cutaneous leishmaniasis, has been isolated from the rodent meriones shawi shawi in central tunisia. as a result, the north saharan arid mediterranean area can be considered as epidemiologically homogeneous.19863729234
inhibition of lymphokine-induced macrophage microbicidal activity against leishmania major by liposomes: characterization of the physicochemical requirements for liposome inhibition.resident peritoneal macrophages from untreated mice develop potent microbicidal activity against amastigotes of leishmania major after in vitro treatment with lymphokine (lk) from mitogen-stimulated spleen cells. lk-induced macrophage microbicidal activity was completely and selectively abrogated by treatment with phosphatidylcholine-phosphatidylserine (pc/ps) liposomes. other macrophage effector functions (phagocytosis, tumoricidal activity) were unaffected, as was cytotoxicity by macrophages a ...19863745916
scanning electron microscopy of leishmania major in phlebotomus papatasi.the morphology of leishmania major parasites and their interactions with various regions of the alimentary canal of phlebotomus papatasi were studied by scanning electron microscopy. parasites were observed to undergo development initiated with the ingestion of amastigotes and culminating in a characteristic distribution of four distinct morphological forms in various parts of the alimentary canal: namely, large numbers of elongate nectomonads in the abdominal mid-gut, haptomonad forms attached ...19863751230
[attempt at cryogenic preservation of the amastigote stage of leishmania major in the ear skin of experimentally infected golden hamsters (mesocricetus auratus)]. 19863762496
the effect of post-bloodmeal nutrition of phlebotomus papatasi on the transmission of leishmania major.to test the effects of post-bloodmeal nutrition of sand flies on the transmission of leishmania major, groups of infected p. papatasi females maintained on diets of sucrose, trehalose, albumin or a mixture of sucrose and albumin, were subjected to forced feeding with capillaries. transmission was evaluated by counting the parasites egested; numbers ranged from 0 to over 1,000 promastigotes. infections of the anterior midgut were seen in the majority of flies from all the experimental groups but ...19863766853
leishmania major and l. donovani: effects on proteolytic enzymes of phlebotomus papatasi (diptera, psychodidae).phlebotomus papatasi is susceptible to leishmania major which it transmits in nature, but is resistant to l. donovani. the present study compares the effect of l. major and l. donovani on the proteolytic activity of p. papatasi gut enzymes. the experiments measured digestion of c14-labeled globin by gut homogenates of flies. homogenates were prepared from flies fed on serum only (controls) or from flies fed serum containing promastigotes or their dried culture overlayer. in other experiments, th ...19863780930
leishmania species: mechanisms of complement activation by five strains of promastigotes.the interaction of fresh serum with promastigotes of leishmania major, l. donovani, l. mexicana mexicana, l. mexicana amazonensis, and l. braziliensis guyanensis results in lysis of all strains tested with either fresh human or guinea pig serum at 37 c for 30 min. lysis does not occur in the cold and requires divalent cations and complement that is active hemolytically. serum deficient in the eighth component of complement is not lytic. lysis of l. major, l. mexicana, and l. braziliensis proceed ...19863780933
passive transfer of leishmania lipopolysaccharide confers parasite survival in macrophages.infection of macrophages by the intracellular protozoan parasite leishmania involves specific attachment to the host membrane, followed by phagocytosis and intracellular survival and growth. two parasite molecules have been implicated in the attachment event: leishmania lipopolysaccharide (l-lps) and a glycoprotein (gp63). this study was designed to clarify the role of l-lps in infection and the stage in the process of infection at which it operates. we have recently identified a leishmania majo ...19863782793
inhibition in vivo of both infective leishmania major and l. mexicana amazonensis mediated by a single monoclonal antibody.monoclonal antibodies raised against a strain of leishmania infantum isolated in greece were produced and tested for their protective effect in an in vivo system (in balb/c mice). a single monoclonal antibody, igg2b isotype, can prevent the development of two leishmania strains in vivo: one of l. major and one of l. mexicana amazonensis. this antibody-mediated protection may be dependent on complement.19863787687
leishmania major: antileishmanial activity of methylbenzethonium chloride.methylbenzethonium chloride (mbcl) decreased the growth of leishmania major promastigotes and amastigotes in vitro. this decrease occurred during 4 days of exposure to the drug at concentrations of 0.1 to 2.5 micrograms ml-1. mbcl at 2 micrograms ml-1 killed almost 100% of the free living promastigotes and 87% of amastigotes within 4 days of treatment. electron microscopy studies showed marked swelling of mitochondria in treated parasites. a possible additional effect on the parasite surface mem ...19863789266
use of the enzyme-linked immunosorbent assay (elisa) for detection of circulating antibodies to human leishmaniasis.in an attempt to lay the background work of immunodiagnosis of human leishmaniasis in taiwan, the usefulness of enzyme-linked immunosorbent assay (elisa) for detection serum antibodies in large regional groups was studied. antigens were prepared from promastigotes of leishmania tropica major recently isolated in our laboratory by chao. one hundred and sixty-five serum samples were collected from medical students of national yang-ming medical college (ym), taipei, 61 from residents of san-hsing d ...19863793392
cell-mediated immunity in experimental cutaneous leishmaniasis.forms of cutaneous leishmaniasis are caused by leishmania major, l. tropica, l. mexicana, l. amazonensis and l. panamensis. like all leishmanial species, these are obligate intracellular parasites of the mononuclear phagocyte system, with a restricted range of vertebrate hosts including humans, dogs, rodents and arboreal animals. the disease evolves chronically, usually with slow healing, but can sometimes become nonhealing, diffuse disseminating or relapsing. the parasite exists within the macr ...198615462732
induction of delayed-type hypersensitivity to leishmania major and the concomitant acceleration of disease development in progressive murine cutaneous leishmaniasis.balb/c mice injected intradermally with 10(5) or higher doses of formaldehyde-fixed promastigotes (ffp) of leishmania major developed strong delayed-type hypersensitivity (dth) to leishmanial antigens injected into the hind footpad 3 to 10 days later. the dth peaked 15 to 18 h after footpad injection and disappeared by 48 h. this specific dth correlated with the homing of 51cr-labeled syngeneic bone marrow cells and the infiltration of proliferating cells to the site of antigen administration. s ...19873818088
experimental infections of the multimammate rat (mastomys natalensis) with leishmania donovani and leishmania major.the susceptibility of the multimammate rat, mastomys natalensis, to experimental infections with leishmania donovani and l. major was examined. inoculations of l. major promastigotes into the skin resulted in nonulcerating lesions in which parasites could be detected for more than 30 weeks later. intravenous inoculations of l. donovani promastigotes produced visceral infections characterized by a continuing increase in splenic parasite burdens and liver parasite burdens which peaked during the f ...19873826485
sequence and s1 nuclease mapping of the 5' region of the dihydrofolate reductase-thymidylate synthase gene of leishmania major.the 5' structure of mrna transcribed from the dihydrofolate reductase-thymidylate synthase (dhfr-ts) gene of the protozoan parasite leishmania major has been characterized. s1 nuclease mapping identifies a heterogenous 5' structure which is not affected by growth phase or developmental stage. the dna sequence of the 5' region of the dhfr-ts gene does not reveal homology with other trypanosomatid genes, eukaryotic consensus genetic elements, or the mammalian dhfr promoter element. this latter fin ...19873554143
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