Avaliação da resposta celular das subpopulações de linfócitos e níveis de plaquetas em pacientes com malária vivax segundo histórico de infecção prévia de malária

Abstract

The innate immune response in the acute phase of malaria results in an immune state that is profoundly altered can protect the host against a grave form of disease. The aim of this study was to evaluate the dynamics of cellular subpopulations of T lymphocytes (CD3+CD4+ e CD3+CD8+), B lymphocytes (CD5+CD19+ e CD5-CD19+) , NK (CD3+CD16+CD56+ e CD16+CD56+) and regulatory T cells ((CD4+CD25+FoxP3+) in patients infected with Plasmodium vivax according to exposure criteria provided malaria and hemoglobin and platelets. During May and November (2012) Peripheral blood samples from patients infected exclusively by P. vivax with uncomplicated malaria were separated into: Group 1 (Primo-infected), Group 2 (Last infection <7 months) and Group 3 (Last infection over 1 year). Mixed infections and co-infections with dengue were excluded by PCR. The expression of adhesion molecules (CD31 and CD54) molecule and memory (CD45RO) and cytokines IL-2, IL-4, IL-6, IL-10, IL-17, TNF-α and IFN-Ɣ, were analyzed by Flow Cytometry. Hematological data showed that patients with vivax malaria had decreased percentages of lymphocytes (p <0.0001) compared to controls. Of the seventy-one patients, 36 were Primo infected; 16 had malaria <7 months and 19 for 1 more year. We observed significant differences in immunophenotyping in relation to the malaria patients recent (<7 months) relative to other features. These patients showed decreased amount of B1 lymphocytes (p=0.042) and T-CD8-CD69 (p=0.027). Was also noted Thrombocytopenia in patients infected with cousin directly proportional correlation with the subpopulations of activated CD4 and CD8 expression and PECAM-1 in CD8 T-lymphocytes. Marked differences in cytokine profile could be observed with cytokines TNF-α compared with IL-10 and IL-6 and the reduction in the number of some lymphocyte subpopulations in patients whose last malaria occurred <7 months. These results would indicate immunocompensation of the immune response against severe disease in these individuals with recent history malaria, and the state is not immune from the Primo-infected patients could contribute to the change in platelet count behaving as a risk factor for the development of thrombocytopenia in malaria.