title: Non PC liposome entrapped promastigote antigens elicit parasite specific CD8+ and CD4+ T-cell immune response and protect hamsters against visceral leishmaniasis.
abstract: Leishmania donovani promastigote soluble antigens (sLAg) were encapsulated in non-phosphatidylcholine (non-PC) liposomes (escheriosomes) prepared from E. coli lipids. The escheriosome-based vaccine was investigated for its potential to elicit a protective immune response against experimental visceral leishmaniasis. The vaccine administration induced strong humoral as well as cell mediated immune responses both in hamsters and BALB/c mice. Immunization of BALB/c mice with escheriosome entrapped sLAg (EL-sLAg) elicited stronger CD8+ cytotoxic T lymphocyte (CTL) response as compared to sLAg entrapped in egg PC/chol liposome (EPC-sLAg) or sLAg administered with incomplete Freund's adjuvant (IFA-sLAg). EL-sLAg also induced the release of mixed (Th1 and Th2) types of cytokines in the immunized BALB/c mice. In addition, the delivery of sLAg via escheriosomes enhanced the expression of costimulatory signals (CD80 and CD86) as determined in peritoneal macrophages obtained from BALB/c mice. In another set of experiments, the EL-sLAg immunized hamsters were found to be better protected than those immunized with EPC-sLAg. The prophylaxis coincided with increased lymphocyte proliferation as well as high nitric oxide (NO) production by peritoneal macrophages among EL-sLAg immunized hamsters. Escheriosomes thus seem to have potential in delivering the antigen to cytosol of the antigen presenting cells (APCs) and in the development of liposome-based vaccine against leishmaniasis as well as other intracellular infections.
authors.affiliation: Inter-Disciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh-202002, India.
authors.forename: Sharad Kumar
authors.initials: SK
authors.lastname: Sharma
authors.forename: Anuradha
authors.initials: A
authors.lastname: Dube
authors.forename: Ahmad
authors.initials: A
authors.lastname: Nadeem
authors.forename: Shazia
authors.initials: S
authors.lastname: Khan
authors.forename: Iram
authors.initials: I
authors.lastname: Saleem
authors.forename: Ravendra
authors.initials: R
authors.lastname: Garg
authors.forename: Owais
authors.initials: O
authors.lastname: Mohammad
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000276:immunology*; D018122:B7-1 Antigen / Q000032:analysis; D051940:B7-2 Antigen / Q000032:analysis; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D049109:Cell Proliferation; D006224:Cricetinae; D016207:Cytokines / Q000032:analysis; D003601:Cytotoxicity Tests, Immunologic; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005620:Freund's Adjuvant / Q000008:administration & dosage / Q000494:pharmacology; D007893:Leishmania donovani / Q000254:growth & development / Q000276:immunology*; D007898:Leishmaniasis, Visceral / Q000469:parasitology / Q000517:prevention & control*; D008081:Liposomes; D017737:Macrophages, Peritoneal / Q000737:chemistry / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009569:Nitric Oxide / Q000096:biosynthesis; D016052:Protozoan Vaccines / Q000008:administration & dosage* / Q000276:immunology*
chemical_list: D000276:Adjuvants, Immunologic; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D018122:B7-1 Antigen; D051940:B7-2 Antigen; D016207:Cytokines; D008081:Liposomes; D016052:Protozoan Vaccines; D009569:Nitric Oxide; D005620:Freund's Adjuvant