Capacity of ArtinM to induce the repolarization of M2 macrophages to M1 in in vitro Paracoccidioides brasiliensis infection

• Grant number: 19/26876-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2020
• End date: June 30, 2021
• Field of knowledge: Biological Sciences - Immunology - Immunochemistry
• Principal Investigator: Maria Cristina Roque Antunes Barreira
• Grantee: Letícia Baccaglini Caetano de Camargo
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated research grant: 18/21708-5 - Application of immunomoduladors, by carbohydrate recognition, as therapeutic agents: mechanism of action to immunotherapy, AP.TEM

Abstract

Paracoccidioidomycosis (PCM) is a disease caused by Paracoccidioides brasiliensis, which caracterizes the most prevalent invasive fungal infection in Latin America and it this disease is iniciated by inhalation of airborne propagules. The P. brasiliensis form inhalated is transformed to yeast form in the human lungs at 35 - 37oC. The PCM can be found in 2 types, the young acute form and adult chronic form, and the young form is more severe and accompanied by lymphatic and lymphogenic dissemination affecting spleen and liver. By side the conventional antifungal therapy, there are studies using other therapeutic strategies against PCM including immunomodulatory molecules (citokines, pentoxifylline) and immunization protocols via pathogen peptides. In this context, the ArtinM lectin has immunomodulatory activity through N-glycan-TLR2/CD14 recognition present on surface of the innate imune cells, and the ArtinM administration in mice favored the control of P. brasiliensis infection. Then, the current proposal aims to evaluate the effect of ArtinM in the repolarization of alveolar and peritoneal macrophages from M2 subset to M1 during in vitro infection within P. brasiliensis. Initially, we will standardize the concentrations of IL-4 and IL-12p40 adequate to induce the M1 and M2 macrophage, moreover, the several MOI (P. brasiliensis : macrophages) will be evaluated in the induction of M1 and M2 subsets. The characterization of macrophage polarization will be performed by qRT-PCR for transcripts of M1 subset (iNOs; STAT1; SOCS3) and M2 subset (Arginase-1; Fizz; YM-1; STAT3; SOCS1). In addition, the capacity of ArtinM to promote the macrophage repolarization from M2 to M1 will be evaluated after suppressor effect of IL-4 and P. brasiliensis. To investigate the effect of immunomodulation induced by ArtinM in the repolarization macrophage over time during the P. brasiliensis infection, the present proposal will focus to demonstrate whether M2 macrophage incubated with ArtinM is able to inhibit the growth of P. brasiliensis in vitro infection. This approach will be performed by colony forming units (CFU) count after co-culture of M2 macrophage, previously stimulated with ArtinM, P. brasiliensis yeast form. Our hypothesis that ArtinM can induce macrophage repolarization from M2 to M1 will open new perspectives in the immunotherapy to fight against PCM, and other mechanisms involved with immunomodulatory activity of ArtinM will be reported.Key-words: P. brasiliensis, lectin, ArtinM, macrophage polarization.