Leishmaniasis: Immune Cells Crosstalk in Macrophage Polarization
Fernanda Silva Almeida, Shayenne Eduarda Ramos Vanderley, Fernando Cézar Comberlang, Arthur Gomes de Andrade, Luiz Henrique Agra Cavalcante‐Silva, Edson dos Santos Silva, Pedro Henrique de Sousa Palmeira, Ian Porto Gurgel do Amaral, Tatjana Souza Lima Keesen
Abstract
Leishmaniasis is a complex infectious parasitic disease caused by protozoa of the genus Leishmania, belonging to a group of neglected tropical diseases. It establishes significant global health challenges, particularly in socio-economically disadvantaged regions. Macrophages, as innate immune cells, play a crucial role in initiating the inflammatory response against the pathogens responsible for this disease. Macrophage polarization, the process of differentiating macrophages into pro-inflammatory (M1) or anti-inflammatory (M2) phenotypes, is essential for the immune response in leishmaniasis. The M1 phenotype is associated with resistance to Leishmania infection, while the M2 phenotype is predominant in susceptible environments. Notably, various immune cells, including T cells, play a significant role in modulating macrophage polarization by releasing cytokines that influence macrophage maturation and function. Furthermore, other immune cells can also impact macrophage polarization in a T-cell-independent manner. Therefore, this review comprehensively examines macrophage polarization’s role in leishmaniasis and other immune cells’ potential involvement in this intricate process.