Effects of Toxoplasma gondii and Paracoccidioides brasiliensis, exerted through their respective lectins on intracellular pathways activated by the recognition of N-linked glycans to toll like receptors on neutrophils

• Grant number: 17/02998-0
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: June 01, 2017
• End date: August 31, 2020
• Field of knowledge: Biological Sciences - Immunology - Applied Immunology
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Maria Cristina Roque Antunes Barreira
• Grantee: Rafael Ricci de Azevedo
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated scholarship(s): 18/16374-0 - Transcriptome analysis of Toxoplasma gondii-infected human neutrophils: roles of MIC1 and MIC4, BE.EP.PD

Abstract

Interest in studying neutrophils has been increased in recent years among many research groups, which look for characterizing new functions and identifying the role exerted by neutrophils in different pathologies. Numerous obligatory or facultative intracellular pathogens can escape from neutrophil responses and thus live and reproduce in the host organism. Some pathogens modulate neutrophils functions to be successful in the infection process, regulating the activation of signaling pathways and controlling host cell survival. The interactions between neutrophils and the pathogens Toxoplasma gondii or Paracoccidioides brasiliensis are poorly studied, concerning the intracellular signaling mechanisms. Indeed, it is known that both pathogens activate myeloid cells through the binding to Toll-like receptors (TLRs). Our research group studies the lectins' interaction with glycoproteins on the surface of mammalian cells, including TLRs. These studies led us to identify and characterize some pathogens' lectins, such as TgMIC1 and TgMIC4, from T. gondii, and Paracoccina (PCN) from P. brasiliensis. These lectins bind to TLRs' N-glycans on myeloid cells, eliciting appropriate responses for influencing the host immunity. Since neutrophils are the first cells migrating into infected sites and intracellular pathogens can subvert the neutrophils' microbicide mechanisms, it is crucial to understand in detail the interaction established between intracellular pathogens and neutrophils. Therefore, the aim of this work is to evaluate the effect of the pathogens T. gondii and P. brasiliensis, and their lectins, on the activation of neutrophil intracellular signaling pathways, triggered by the recognition of glycans N-linked to TLRs. Then, human neutrophils will be stimulated with the mentioned lectins or infected with the focused pathogens and assessed by western blot for the activation of signaling pathways, such as MAPK - P38 and ERK1 / 2, mTOR, AKT, PI3K, JNK, TAK1. We will used the same approach in assays with transformed pathogens, which are knocked out, deficient or presenting superexpression of the lectins, to evaluate their role in triggering the obtained neutrophils phenotypes. Also, we will use models of infection in mice that were knocked out for TNF receptor, TLRs, dectin, and eventually others, with the purpose of identifying the primary neutrophils targets for the pathogens or their lectins. Finally, gene expression analysis of infected or lectin-stimulated neutrophils will allow to precisely determining the mechanisms involved in the interaction of neutrophils with the studied pathogens. By understanding the determinant mechanisms of the interactions established by innate immune receptors on neutrophils and pathogens components, it will be possible to create new therapeutic strategies against infectious diseases, in particular against the caused by T. gondii and P. brasiliensis. (AU)

Scientific publications

(5)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

BATISTA, BIANCA BONTEMPI; RODRIGUES DE SOUZA SANTOS, RENATO ELIAS; RICCI-AZEVEDO, RAFAEL; SILVA NETO, JOSE FREIRE. Production and Uptake of Distinct Endogenous Catecholate-Type Siderophores Are Required for Iron Acquisition and Virulence in Chromobacterium violaceum. Infection and Immunity, v. 87, n. 12, DEC 2019. (18/01388-6, 12/20435-9, 17/03342-0, 17/02998-0)

MENDONCA-NATIVIDADE, FLAVIA COSTA; LOPES, CARLA DUQUE; RICCI-AZEVEDO, RAFAEL; SARDINHA-SILVA, ALINE; PINZAN, CAMILA FIGUEIREDO; PAIVA ALEGRE-MALLER, ANA CLAUDIA; NOHARA, LILIAN L.; CARNEIRO, ALAN B.; PANUNTO-CASTELO, ADEMILSON; ALMEIDA, IGOR C.; et al. Receptor Heterodimerization and Co-Receptor Engagement in TLR2 Activation Induced by MIC1 and MIC4 from Toxoplasma gondii. INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES, v. 20, n. 20, OCT 2 2019. (13/04088-0, 17/02998-0, 14/13324-1)

GONCALES, RELBER AGUIAR; RICCI-AZEVEDO, RAFAEL; VIEIRA, VANESSA C. S.; FERNANDES, FABRICIO F.; THOMAZ, SANDRA M. DE O.; CARVALHO, AGOSTINHO; VENDRUSCOLO, PATRICIA E.; CUNHA, CRISTINA; ROQUE-BARREIRA, MARIA CRISTINA; RODRIGUES, FERNANDO. Paracoccin Overexpression in Paracoccidioides brasiliensis Enhances Fungal Virulence by Remodeling Chitin Properties of the Cell Wall. Journal of Infectious Diseases, v. 224, n. 1, p. 164-174, JUL 1 2021. (14/22561-7, 17/02998-0, 13/04088-0, 18/21708-5, 16/00629-4)

RICCI-AZEVEDO, RAFAEL; COSTA MENDONCA-NATIVIDADE, FLAVIA; CAROLINA SANTANA, ANA; ALCOFORADO DINIZ, JULIANA; CRISTINA ROQUE-BARREIRA, MARIA. Microneme Proteins 1 and 4 From Toxoplasma gondii Induce IL-10 Production by Macrophages Through TLR4 Endocytosis. FRONTIERS IN IMMUNOLOGY, v. 12, APR 12 2021. (16/10446-4, 17/02998-0, 18/21708-5, 16/14657-0, 14/13324-1, 13/04088-0)

DINIZ, JULIANA ALCOFORADO; CHAVES, MARIANA M.; VASELEK, SLAVICA; MISERANI MAGALHAES, RUBENS D.; RICCI-AZEVEDO, RAFAEL; DE CARVALHO, RENAN V. H.; LORENZON, LUCAS B.; FERREIRA, TIAGO R.; ZAMBONI, DARIO; WALRAD, PEGINE B.; et al. Protein methyltransferase 7 deficiency in Leishmania major increases neutrophil associated pathology in murine model. PLoS Neglected Tropical Diseases, v. 15, n. 3, MAR 2021. (19/18607-5, 16/14657-0, 18/02761-2, 17/02998-0, 15/13618-8, 16/00969-0)