Characterization of the immune response to Leishmania infantum recombinant antigens.
Leishmaniases have a high prevalence in tropical countries. In order to improve existing diagnostic systems based on total Leishmania proteins, and to identify antigen candidates for vaccine development, an intensive search for the identification of antigens was performed using molecular biology techniques. In this study, the immune response to three L. infantum recombinant antigens was evaluated. Upon stimulation with KMP11, mononuclear cells from leishmaniasis patients produced high levels of IL-10, while a predominant IFN-gamma production could be observed in cultures stimulated with H2A and soluble Leishmania antigen. All the recombinant antigens induced very little IL-5. KMP11 decreased IFN-gamma production by 48% in cultures of peripheral blood mononuclear cells from cutaneous leishmaniasis patients who had been stimulated with soluble Leishmania antigen. Furthermore, antibodies to KMP11 were detected in the sera from all patients with visceral leishmaniasis and in the majority of the sera from patients with cutaneous leishmaniasis or individuals with asymptomatic L. chagasi infection. Thus, KMP11 is recognized by cells and sera of patients with different clinical forms of leishmaniasis, and KMP11, through IL-10 production, proved to be a potent antigen in modulating type 1 immune response.
de Carvalho
Lucas Pedreira
LP
Serviço de Imunologia do Hospital Universitário Prof. Edgard Santos, Universidade Federal da Bahia, 5 degrees andar, Rua João das Botas s/n, Canela 40110-160, Salvador, Bahia, Brazil.
Soto
Manuel
M
Jerônimo
Selma
S
Dondji
Blaise
B
Bacellar
Olívia
O
Luz
Viviane
V
Orge Orge
Glória
G
Alonso
Carlos
C
Jesus
Amélia R
AR
Carvalho
Edgar M
EM
D000818:Animals; D000953:Antigens, Protozoan / Q000235:genetics / Q000276:immunology*; D002478:Cells, Cultured; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007371:Interferon-gamma / Q000032:analysis / Q000037:antagonists & inhibitors; D016753:Interleukin-10 / Q000819:agonists / Q000032:analysis; D015848:Interleukin-5 / Q000032:analysis; D018314:Leishmania infantum / Q000276:immunology*; D016773:Leishmaniasis, Cutaneous / Q000276:immunology*; D007898:Leishmaniasis, Visceral / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000276:immunology / Q000494:pharmacology; D015800:Protozoan Proteins / Q000276:immunology / Q000494:pharmacology; D011994:Recombinant Proteins / Q000276:immunology
D000953:Antigens, Protozoan; D007074:Immunoglobulin G; D015848:Interleukin-5; D008562:Membrane Glycoproteins; D015800:Protozoan Proteins; D011994:Recombinant Proteins; C090009:kinetoplastid membrane protein 11, Leishmania donovani; D016753:Interleukin-10; D007371:Interferon-gamma