Leishmania donovaniNucleoside Hydrolase (NH36) Domains Induce T-Cell Cytokine Responses in Human Visceral Leishmaniasis.
Development of immunoprotection against visceral leishmaniasis (VL) focused on the identification of antigens capable of inducing a Th1 immune response. Alternatively, antigens targeting the CD8 and T-regulatory responses are also relevant in VL pathogenesis and worthy of being included in a preventive human vaccine. We assessed in active and cured patients and VL asymptomatic subjects the clinical signs and cytokine responses to theLeishmania donovaninucleoside hydrolase NH36 antigen and its N-(F1), central (F2) and C-terminal (F3) domains. As markers of VL resistance, the F2 induced the highest levels of IFN-γ, IL-1β, and TNF-α and, together with F1, the strongest secretion of IL-17, IL-6, and IL-10 in DTH+and cured subjects. F2 also promoted the highest frequencies of CD3+CD4+IL-2+TNF-α-IFN-γ-, CD3+CD4+IL-2+TNF-α+IFN-γ-, CD3+CD4+IL-2+TNF-α-IFN-γ+, and CD3+CD4+IL-2+TNF-α+IFN-γ+T cells in cured and asymptomatic subjects. Consistent with this, the IFN-γ increase was correlated with decreased spleen (R= -0.428,P= 0.05) and liver sizes (R= -0.428,P= 0.05) and with increased hematocrit counts (R= 0.532,P= 0.015) in response to F1 domain, and with increased hematocrit (R= 0.512,P0.02) and hemoglobin counts (R= 0.434,P= 0.05) in response to F2. Additionally, IL-17 increases were associated with decreased spleen and liver sizes in response to F1 (R= -0.595,P= 0.005) and F2 (R= -0.462,P= 0.04). Conversely, F1 and F3 increased the CD3+CD8+IL-2+TNF-α-IFN-γ-, CD3+CD8+IL-2+TNF-α+IFN-γ-, and CD3+CD8+IL-2+TNF-α+IFN-γ+T cell frequencies of VL patients correlated with increased spleen and liver sizes and decreased hemoglobin and hematocrit values. Therefore, cure and acquired resistance to VL correlate with the CD4+-Th1 and Th-17 T-cell responses to F2 and F1 domains. Clinical VL outcomes, by contrast, correlate with CD8+T-cell responses against F3 and F1, potentially involved in control of the early infection. Thein silico-predicted NH36 epitopes are conserved and bind to many HL-DR and HLA and B allotypes. No human vaccine againstLeishmaniais available thus far. In this investigation, we identified the NH36 domains and epitopes that induce CD4+and CD8+T cell responses, which could be used to potentiate a human universal T-epitope vaccine against leishmaniasis.
Laboratório de Biologia Molecular, Hospital Universitário, Departamento de Medicina, Universidade Federal de Sergipe (HU-UFS) , Aracaju, Sergipe , Brazil.
Micheli Luize
ML
Barbosa Santos
Laboratório de Biologia e Bioquímica de Leishmania, Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro (UFRJ) , Rio de Janeiro, Rio de Janeiro , Brazil.
Dirlei
D
Nico
Laboratório de Biologia Molecular, Hospital Universitário, Departamento de Medicina, Universidade Federal de Sergipe (HU-UFS) , Aracaju, Sergipe , Brazil.
Fabrícia Alvisi
FA
de Oliveira
Laboratório de Biologia Molecular, Hospital Universitário, Departamento de Medicina, Universidade Federal de Sergipe (HU-UFS) , Aracaju, Sergipe , Brazil.
Aline Silva
AS
Barreto
Laboratório de Biometrologia, Programa de Pós-Graduação em Metrologia, Pontifícia Universidade Católica do Rio de Janeiro , Rio de Janeiro, Rio de Janeiro , Brazil.
Iam
I
Palatnik-de-Sousa
WHO Collaborating Centre for Leishmaniasis, Instituto de Salud Carlos III, Centro Nacional de Microbiologia , Madrid, Comunidad de Madrid , Spain.
Eugenia
E
Carrillo
WHO Collaborating Centre for Leishmaniasis, Instituto de Salud Carlos III, Centro Nacional de Microbiologia , Madrid, Comunidad de Madrid , Spain.
Javier
J
Moreno
Laboratório de Imunoparasitologia, Instituto Oswaldo Cruz (IOC) , Rio de Janeiro, Rio de Janeiro , Brazil.
Paula Mello
PM
de Luca
Laboratório de Imunologia Integrada, Departamento de Imunologia, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro (UFRJ) , Rio de Janeiro, Rio de Janeiro , Brazil.
Alexandre
A
Morrot
Faculdade de Medicina, Instituto de Investigação em Imunologia, Universidade de São Paulo (USP), São Paulo, Brazil; Laboratório de Vacinas experimentais, Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo (UNIFESP), São Paulo, São Paulo, Brazil.
Daniela Santoro
DS
Rosa
Laboratório de Imunohematologia, Faculdade de Medicina, Hospital Universitário Clementino Fraga-Filho, Universidade Federal do Rio de Janeiro (UFRJ) , Rio de Janeiro, Rio de Janeiro , Brazil.
Marcos
M
Palatnik
Departamento de Morfologia, Universidade Federal de Sergipe (HU-UFS) , Aracaju, Sergipe , Brazil.
Cristiane
C
Bani-Corrêa
Laboratório de Biologia Molecular, Hospital Universitário, Departamento de Medicina, Universidade Federal de Sergipe (HU-UFS), Aracaju, Sergipe, Brazil; Faculdade de Medicina, Instituto de Investigação em Imunologia, Universidade de São Paulo (USP), São Paulo, Brazil.
Roque Pacheco
RP
de Almeida
Laboratório de Biologia e Bioquímica de Leishmania, Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Rio de Janeiro, Brazil; Faculdade de Medicina, Instituto de Investigação em Imunologia, Universidade de São Paulo (USP), São Paulo, Brazil.
Clarisa Beatriz
CB
Palatnik-de-Sousa
Leishmania donovani; Leishmania infantum chagasi; T cell epitopes; epitope vaccine design; human visceral leishmaniasis; nucleoside hydrolase; recombinant domains