Investigação do perfil da citocina th17a e outras citocinas pró-inflamatórias em pacientes com hanseníase

Abstract

Leprosy is a chronic infectious disease characterized by dermato-neurological manifestations. Leprosy patients are clinically classified into two large groups as paucibacillary (PB) and multibacillary (MB). PB patients present a polarization of the Th1 immune response, with a strong cellular response and destruction of the bacillus. MB patients polarize the immune response to Th2 lymphocytes with antibody formation, and there is no destruction of the bacterium leading to an uncontrolled form of the disease. Leprosy reactions usually occur after initiation of multidrug therapy (MDT) as a result of an exacerbated immune response of PB and MB individuals. These reactions commonly cause permanent damage to patients. They are classified as Type 1 Reaction (RT1) or Reverse Reaction (RR) and Type 2 Reaction (RT2). Another subpopulation of CD4 + T cells, Th17 and its respective signature cytokine, IL-17A, may present a relevant response in the pathogenesis of leprosy. However, there are few studies attempting to describe the role of Th17 in leprosy. In addition, some of these studies have conflicting results, therefore it is important to carry out new studies that try to better elucidate the function of Th17 cells in Hansen's disease. The objective of this work was to analyze the profile of several cytokines, especially those related to the Th17 immunological pattern, in patients with leprosy and leprosy reaction. Our results demonstrate that inflmmatory cytokines, IL-17, IL-1, IL-12 and INF-γ, are elevated in PB patients and especially in individuals with RT1 and RT2. In contrast, IL-4 and IL-10 anti-inflammatory cytokines were elevated in MB and decreased in PB, RT1 and RT2.The exaggerated immune response with harmful potential observed in patients with leprosy episodes can be justified by the increase of IL-17A. This interleukin is highly inflammatory which leads to an increase in neutrophil recruitment with consequent tissue damage.