title: Vaccination with DNA encoding ORFF antigen confers protective immunity in mice infected with Leishmania donovani.
abstract: The gene ORFF is part of the multigenic LD1 locus on chromosome 35 that is frequently amplified in Leishmania. The function of ORFF is unknown. The gene encoding ORFF was cloned into a eukaryotic expression vector downstream to the cytomegalovirus (CMV) promoter. BALB/c mice were injected intramuscularly with ORFF DNA and challenged with Leishmania donovani promastigotes. Vaccination with ORFF gene induced both humoral and cellular immune response against ORFF, which provided significant level of protection against challenge with L. donovani. A qualitative PCR was used to determine whether activation of Th1 cells develops selectively in response to this ORFF DNA vaccine. The results indicated that mRNA for IFN-gamma was significantly induced in immunized mice. No significant change in IL-4 mRNA expression was observed in mice immunized with ORFF DNA vaccine versus mice immunized with control plasmid. Thus, DNA immunization may offer an attractive alternative strategy against leishmaniasis.
authors.affiliation: School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
authors.forename: Bindu
authors.initials: B
authors.lastname: Sukumaran
authors.forename: Poonam
authors.initials: P
authors.lastname: Tewary
authors.forename: Shailendra
authors.initials: S
authors.lastname: Saxena
authors.forename: Rentala
authors.initials: R
authors.lastname: Madhubala
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000096:biosynthesis / Q000276:immunology; D000953:Antigens, Protozoan / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D019556:COS Cells; D002522:Chlorocebus aethiops; D005260:Female; D005786:Gene Expression Regulation; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000096:biosynthesis / Q000235:genetics; D015847:Interleukin-4 / Q000096:biosynthesis / Q000235:genetics; D007893:Leishmania donovani / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D007898:Leishmaniasis, Visceral / Q000276:immunology / Q000469:parasitology / Q000517:prevention & control*; D008099:Liver / Q000276:immunology / Q000469:parasitology; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D018482:Muscle, Skeletal / Q000276:immunology; D010957:Plasmids / Q000235:genetics / Q000276:immunology; D016133:Polymerase Chain Reaction; D015800:Protozoan Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D016052:Protozoan Vaccines / Q000276:immunology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D013154:Spleen / Q000276:immunology / Q000469:parasitology; D018417:Th1 Cells / Q000276:immunology; D014162:Transfection; D014611:Vaccination; D019444:Vaccines, DNA / Q000276:immunology*
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; C402106:ORFF protein, Leishmania; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; D012333:RNA, Messenger; D019444:Vaccines, DNA; D015847:Interleukin-4; D007371:Interferon-gamma