Effect of rIL-7 in the M1 and M2 macrofage phenotypes after Leishmania infantum infection.

• Grant number: 22/06106-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): October 01, 2022
• Effective date (End): September 30, 2023
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Preventive Veterinary Medicine
• Principal Investigator: Valéria Marçal Felix de Lima
• Grantee: Lucas Caetano de Castro Zocante
• Host Institution: Faculdade de Medicina Veterinária (FMVA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

Zoonotic visceral leishmaniasis is caused by the parasite Leishmania infantum. Dogs are considered the most important urban reservoirs of this parasite due to the high rate of infection and transmission to humans. The parasite promotes host immunosuppression which allows its replication in macrophages. Macrophage polarization for the M2 profile is coincident with high macrophage parasitism in dogs with leishmaniasis. Therapeutic measures include the use of drugs such as miltefosine, allopurinol and meglubin antimoniate, which can be toxic, ineffective and expensive. In this sense, interleukin - 7 (IL-7), a pleiotropic cytokine, essential to restore the functions of immune system cells, may be an alternative treatment. IL-7 is a potent inducer of macrophages for the M1 profile with secretion of inflammatory cytokines and production of nitric oxide (NO), one of the main leishmanicidal mechanisms. Thus, we intend to evaluate in vitro whether canine macrophages infected with Leishmania infantum and stimulated with recombinant IL-7 can increase the microbicidal capacity and induce polarization to M1.