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Immuno-Biochemical Alterations in Leishmania major Infected Balb/c Mice after Immunization with Killed Leishmania Vaccine and BCG as Adjuvant  [cached]
Sara Nemati,Seyedeh Parisa Jafary,Hossein Nahrevanian,Mahin Farahmand
Current Research Journal of Biological Sciences , 2012,
Abstract: BCG is an immune modulatory that inducing humoral and cellular immune responses during a number of infections including cutaneous leishmaniasis. Killed Leishmania Vaccine (KLV) has been applied for its immunogenicity in hosts. This study was carried out between 2010 and 2011 at the Department of Parasitology, Pasteur Institute of Iran. In the present study, alterations of Nitric Oxide (NO) levels, total content of essential trace elements (Cu, Zn) and liver enzymes (SGOT, SGPT) were investigated in Balb/c mice infected with Leishmania major. Results showed that BCG induced NO in liver; Zn increased in KLV/BCG and KLV test groups and Cu decreased in KLV test group, but increased in BCG test group. Moreover to decreasing SGOT level in KLV/BCG test group, SGPT decreased in BCG test group. Our findings showed that serum trace element concentrations were altered in CL infection, probably in accordance with host defense mechanisms. It is indicated that application of KLV/BCG as a combined vaccine/adjuvant could be indicated as a potent inducer of immuno-biochemical characters during infection with Leishmaniasis. In conclusion, some dependency is observed between KLV/BCG and NO levels, Cu, Zn concentrations and SGOT, SGPT production. The mechanism of KLV/BCG action may be associated more on BCG rather than KLV.
Pathogenicity Variations of Susceptibility and Resistance to Leishmania major MRHO/IR/75/ER Strain in BALB/c and C57BL/6 mice
Marzieh Amini,Hossein Nahrevanian,Mahin Farahmand
Iranian Journal of Parasitology , 2008,
Abstract: Background: To compare the pathogenicity differences in two susceptible Balb/c and resistant C57bl/6 mice infected with Leishmania major MRHO/IR/75/ER as a prevalent strain of zoonotic cutaneous leishmaniasis in Iran. Methods: Mice were assigned into four groups as control and infected BALB/c and C57BL/6 mice. Experimental leishma-niasis was initiated by (s. c) injection of the 2×106 L. major promastigotes into the basal tail of infected groups. The devel-opment of lesions was determined weekly by measuring the two diameters. After 10 weeks, all mice were killed humanly, target tissues including lymph node, spleen and liver from each mouse were removed, weighted, and their impression smears were prepared. Results: Proliferation of amastigotes inside macrophages, pathogenicity signs in two susceptible, resistant hosts was varied, and these variations were depended on mice strain. Conclusion: Host immunity may modify clinical signs and could affect the proliferation of amastigotes inside macro-phages, the size of lesions, the survival rates, the degree of hepatomegaly and splenomegaly and the percentage of amasti-gotes in lesion, liver, spleen, lymph node and brain smears.
Sphingolipid Degradation in Leishmania (Leishmania) amazonensis  [PDF]
Agiesh Balakrishna Pillai equal contributor,Wei Xu equal contributor,Ou Zhang,Kai Zhang
PLOS Neglected Tropical Diseases , 2012, DOI: 10.1371/journal.pntd.0001944
Abstract: Background Human leishmaniasis is caused by more than 20 Leishmania species and has a wide range of symptoms. Our recent studies have demonstrated the essential role of sphingolipid degradation in the virulence of Leishmania (Leishmania) major, a species responsible for localized cutaneous leishmaniasis in the Old World. In this study, we investigated the function of sphingolipid degradation in Leishmania (Leishmania) amazonensis, an etiological agent of localized and diffuse cutaneous leishmaniasis in South America. Methodology/Principal Findings First, we identified the enzyme LaISCL which is responsible for sphingolipid degradation in L. amazonensis. Primarily localized in the mitochondrion, LaISCL shows increased expression as promastigotes progress from replicative log phase to non-replicative stationary phase. To study its function, null mutants of LaISCL (Laiscl?) were generated by targeted gene deletion and complemented through episomal gene add-back. In culture, loss of LaISCL leads to hypersensitivity to acidic pH and poor survival in murine macrophages. In animals, Laiscl? mutants exhibit severely attenuated virulence towards C57BL6 mice but are fully infective towards BALB/c mice. This is drastically different from wild type L. amazonensis which cause severe pathology in both BALB/c and C57BL 6 mice. Conclusions/Significance A single enzyme LaISCL is responsible for the turnover of sphingolipids in L. amazonensis. LaISCL exhibits similar expression profile and biochemical property as its ortholog in L. major. Deletion of LaISCL reduces the virulence of L. amazonensis and the outcome of Laiscl?-infection is highly dependent on the host's genetic background. Therefore, compared to L. major, the role of sphingolipid degradation in virulence is substantially different in L. amazonensis. Future studies may reveal whether sphingolipid degradation is required for L. amazonensis to cause diffuse cutaneous infections in humans.
Immune response to Leishmania (Leishmania) chagasi infection is reduced in malnourished BALB/c mice
Serafim, Tiago Donatelli;Malafaia, Guilherme;Silva, Marcelo Eustáquio;Pedrosa, Maria Lúcia;Rezende, Simone Aparecida;
Memórias do Instituto Oswaldo Cruz , 2010, DOI: 10.1590/S0074-02762010000600014
Abstract: protein-energy malnutrition and micronutrient deficiencies may down-regulate immune response and increase morbidity and mortality due to infection. in this study, a murine model was used to study the effects of protein, iron and zinc deficiencies on the immune response to leishmania (leishmania) chagasi infection. mice were initially fed a standard diet or with a diet containing 3% casein but deficient in zinc and iron. after malnutrition was established, mice were inoculated with l. chagasiand sacrificed four weeks later in order to evaluate liver and spleen parasite loads and serum biochemical parameters. significant decreases in liver and spleen weight, an increase in the parasite loads in these organs and decreases in serum protein and glucose concentrations in malnourished animals were observed. furthermore, the production of interferon-gamma by spleen cells from infected malnourished mice stimulated by leishmaniaantigen was significantly lower compared with that in control diet mice. these data suggest that malnutrition alters the immune response to l. chagasiinfection in the balb/c model and, in association with the effects on biochemical and anatomical parameters of the host, favored increases in the parasite loads in the spleens and livers of these animals.
Kinetics of Antibody Response in BALB/c and C57BL/6 Mice Bitten by Phlebotomus papatasi  [PDF]
Michaela Vlkova ,Iva Rohousova,Jitka Hostomska,Lucia Pohankova,Lenka Zidkova,Jan Drahota,Jesus G. Valenzuela,Petr Volf
PLOS Neglected Tropical Diseases , 2012, DOI: 10.1371/journal.pntd.0001719
Abstract: Background Phlebotomine sand flies are blood-sucking insects transmitting Leishmania parasites. In bitten hosts, sand fly saliva elicits specific immune response and the humoral immunity was shown to reflect the intensity of sand fly exposure. Thus, anti-saliva antibodies were suggested as the potential risk marker of Leishmania transmission. In this study, we examined the long-term kinetics and persistence of anti-Phlebotomus papatasi saliva antibody response in BALB/c and C57BL/6 mice. We also tested the reactivity of mice sera with P. papatasi salivary antigens and with the recombinant proteins. Methodology/Principal Findings Sera of BALB/c and C57BL/6 mice experimentally bitten by Phlebotomus papatasi were tested by ELISA for the presence of anti-saliva IgE, IgG and its subclasses. We detected a significant increase of specific IgG and IgG1 in both mice strains and IgG2b in BALB/c mice that positively correlated with the number of blood-fed P. papatasi females. Using western blot and mass spectrometry we identified the major P. papatasi antigens as Yellow-related proteins, D7-related proteins, antigen 5-related proteins and SP-15-like proteins. We therefore tested the reactivity of mice sera with four P. papatasi recombinant proteins coding for most of these potential antigens (PpSP44, PpSP42, PpSP30, and PpSP28). Each mouse serum reacted with at least one of the recombinant protein tested, although none of the recombinant proteins were recognized by all sera. Conclusions Our data confirmed the concept of using anti-sand fly saliva antibodies as a marker of sand fly exposure in Phlebotomus papatasi–mice model. As screening of specific antibodies is limited by the availability of salivary gland homogenate, utilization of recombinant proteins in such studies would be beneficial. Our present work demonstrates the feasibility of this implementation. A combination of recombinant salivary proteins is recommended for evaluation of intensity of sand fly exposure in endemic areas and for estimation of risk of Leishmania transmission.
Cell migration induced by Leishmania (Leishmania) amazonensis, Leishmania (Leishmania) major and Leishmania (Viannia) braziliensis into the peritoneal cavity of BALB/c mice
Wakimoto, DT;Gaspareto, KV;Silveira, TGV;Lonardoni, MVC;Aristides, SMA;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2010, DOI: 10.1590/S1678-91992010000100017
Abstract: in american cutaneous leishmaniasis, the initial infection phase is characterized by recruitment of neutrophils and monocytes. the migration of these cells in response to the presence of leishmania in the peritoneum of affected animals remains unclear. the objective of this study was to investigate cell migration to the peritoneum of balb/c mice after infection with leishmania (leishmania) amazonensis, leishmania (viannia) braziliensis and leishmania (leishmania) major. initially, leishmania spp. was intraperitoneally inoculated in five groups of six animals each and the cell migration was analyzed 0, 3, 6, 12, 24 and 48 hours after infection. different cell counts were performed with a staining kit and showed a higher percentage of polymorphonuclear than mononuclear cells in all three species studied. the total cell count revealed peak migration in l. (l.) amazonensis and l. (l.) major at six hours, and in l. (v.) braziliensis at 12 hours. these results suggest that factors released from different cell types probably act by attracting polymorphonuclear cells, with the peak migration most likely depending on the species of leishmania inoculated into the host.
The Multiple Forms of Leishmania Major in BALB/C Mice Lung in Iran
Sh Shirbazou,M Jafari
Iranian Journal of Parasitology , 2012,
Abstract: Cutaneous leishmaniasis is one of the most important parasitic diseases, which are endemic in different parts of Iran. Leishmania major and L. tropica are the primary causative agents of this disease. The aim of the present study was to detect the multiple forms of L. major in lung. Ppromastigotes of L. major at stationary phase were injected to BALB/c mice. After 60 days, the different forms of Leishmania parasites were checked in lung tissue. Promastigote and amastigote forms of Leishmania parasites were detected.
Immunization of Balb/C Mice by Protein Fragments of Lizard Leishmania promastigote
B. Kazemi,F. Moazzen,A. Abadi,A. Ghadjari
Pakistan Journal of Biological Sciences , 2004,
Abstract: The objective of this study was the immunization of balb/C mice by protein fragments of lizard Leishmania promastigote. Mice were divided in 6 case groups and one as control. Each group received a fraction of lizard Leishmania promastigote. Then active pathogenic Leishmania major challenged them separately. We followed up all the case groups (6 groups) till five months after the challenge with Leishmania major together with control group and recorded the lesions diameter. None of the mice manifested detectable wound or nodules, except those at group 6 but the difference compared to control group was not significant according to the Mann-Whitney analytical test.
Persistence of Leishmania antigen in C57Bl/6j inbred mice infected with Leishmania (Leishmania) amazonensis
Vasconcellos, C.;Kauffman, M.R.;Sotto, M. N.;
Revista da Associa??o Médica Brasileira , 1999, DOI: 10.1590/S0104-42301999000300006
Abstract: purpose. to develop an animal model for studying mucocutaneous leishmaniasis. methods. the hind footpad of c57bl/6j inbred mice was experimentally infected with 107 leishmania (leishmania) amazonensis promastigote and the skin was studied through light and electron transmission microscopy and immunohistochemistry (pap) techniques. results. there were morphological evidences of cellular immune mechanisms and hypersensitivity reaction after eight weeks of infection and metastasis and well shaped parasites at ultrastructural level by fifty-one weeks post infection. relapse of infection with mucosa lesions occurred around the 50th week after inoculation. conclusion. the use of this animal model in long term follow up could be an useful experimental model for human mucocutaneous leishmaniasis.
Persistence of Leishmania antigen in C57Bl/6j inbred mice infected with Leishmania (Leishmania) amazonensis
Vasconcellos C.,Kauffman M.R.,Sotto M. N.
Revista da Associa??o Médica Brasileira , 1999,
Abstract: PURPOSE. To develop an animal model for studying mucocutaneous leishmaniasis. METHODS. The hind footpad of C57Bl/6j inbred mice was experimentally infected with 10(7) Leishmania (Leishmania) amazonensis promastigote and the skin was studied through light and electron transmission microscopy and immunohistochemistry (PAP) techniques. RESULTS. There were morphological evidences of cellular immune mechanisms and hypersensitivity reaction after eight weeks of infection and metastasis and well shaped parasites at ultrastructural level by fifty-one weeks post infection. Relapse of infection with mucosa lesions occurred around the 50th week after inoculation. CONCLUSION. The use of this animal model in long term follow up could be an useful experimental model for human mucocutaneous leishmaniasis.
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