title: Immunogenicity of the P-8 amastigote antigen in the experimental model of canine visceral leishmaniasis.
abstract: The P-8 proteoglycolipid complex (P-8 PGLC), an amastigote antigen of Leishmania pifanoi, has been demonstrated to induce protection in mouse models, as well as to induce Tc1/Th1-like cellular responses in American cutaneous leishmaniasis patients. Because the immunization with P-8 PGLC in the murine model does not appear to be genetically restricted, we have studied the reactivity of the P-8 PGLC in Leishmania infantum infected dogs. In this study, it is shown that PBMC from experimentally infected dogs (asymptomatic, oligosymptomatic) significantly proliferated in response to soluble leishmanial antigen (SLA) or the P-8 PGLC. Further, quantification of the gene expression induced by the stimulation with P-8 in asymptomatically infected dogs showed an up-regulation of IFN-gamma and TNF-alpha, which were three to 4-fold higher than that induced by soluble Leishmania antigen (SLA). While no measurable induction of IL-10 was observed, low levels of IL-4 mRNA were observed in response to both P-8 and SLA antigens. Thus, our studies establish that P-8 is recognized by infected canines and elicits a potentially curative/protective Th1-like immune response. The identification of Leishmania antigens that elicit appropriate immune responses across different host species (humans, canine) and disease manifestations (cutaneous or visceral) could be an advantage in generating a general vaccine for leishmaniasis.
authors.affiliation: WHO Collaborating Centre for Leishmaniasis, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo km. 2, 28220 Madrid, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Carrillo
authors.forename: S
authors.initials: S
authors.lastname: Ahmed
authors.forename: K
authors.initials: K
authors.lastname: Goldsmith-Pestana
authors.forename: J
authors.initials: J
authors.lastname: Nieto
authors.forename: Y
authors.initials: Y
authors.lastname: Osorio
authors.forename: B
authors.initials: B
authors.lastname: Travi
authors.forename: J
authors.initials: J
authors.lastname: Moreno
authors.forename: D
authors.initials: D
authors.lastname: McMahon-Pratt
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000096:biosynthesis / Q000276:immunology; D000953:Antigens, Protozoan / Q000276:immunology*; D016207:Cytokines / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D004283:Dog Diseases / Q000276:immunology* / Q000469:parasitology*; D004285:Dogs; D005260:Female; D007371:Interferon-gamma / Q000276:immunology; D018314:Leishmania infantum / Q000276:immunology* / Q000469:parasitology; D007898:Leishmaniasis, Visceral / Q000276:immunology* / Q000469:parasitology; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008213:Lymphocyte Activation; D016052:Protozoan Vaccines / Q000276:immunology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D018417:Th1 Cells / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D016207:Cytokines; D016052:Protozoan Vaccines; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma