In vitro evaluation of the contribution of CCL2/MCP-1 and the importance of chemokines in the mechanisms of resistance and susceptibility to infection with Leptospira sp.

• Grant number: 13/16451-1
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2014
• End date: April 30, 2017
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Josefa Bezerra da Silva
• Grantee: Josefa Bezerra da Silva
• Host Institution: Instituto Butantan. Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Associated researchers: Elizabeth Angelica Leme Martins ; Enéas de Carvalho ; Marcelo de Franco ; Paulo Lee Ho ; Renata Maria Augusto da Costa

Abstract

Leptospirosis is a zoonotic disease widely disseminated in various parts of the world. The disease is caused by spirochetes of the genus Leptospira that infect humans and animals. Among the pathogenic species, L. interrogans is the most important cause of disease in humans. In Brazil, the disease is considered endemic with seasonal epidemic outbreaks, representing a serious public health problem. The bacterium spreads via the circulatory system, colonizing the target organs. The pathogenesis in humans is observed mainly in the lung with cases of pulmonary haemorrhage and acute respiratory failure, lesions in liver tissue and kidneys, leading to renal failure. Several in vivo and in vitro studies have assessed the damage caused by infections with L. interrogans, but the importance of the innate immune system action mechanisms on leptospirosis is not well known. CCL2 (MCP-1) is an inflammatory chemokine which acts on the displacement of monocytes/macrophages, acts as an angiogenic factor and presents antagonistic actions for some groups of bacteria. Besides that, it acts in the regulation of transcription of genes involved in the host immune response. In this study we will evaluate the contribution of MCP-1 on the mechanisms of the invasion and control of L. interrogans strains in cell lines of monocyte/macrophage (RAW 264-7) and leukocytes isolated from spleen of C3H/HeJ and BALB/c mice. Furthermore, we will assess the expression pattern of cytokines and chemokines in infected cells and animals with L. interrogans, correlating with the resistance mechanisms in leptospirosis. The virulence of L. interrogans will be maintained by inoculation in golden hamster (Mesocricetus auratus). The bacteria will be isolated from the organs (liver, kidney and lung) of the animals and cultured in EMJH medium. Virulent bacteria will be inoculated into monocytes/macrophages cell cultures and spleen cell isolated from C3H/HeJ and BALB/c for analysis of the MCP-1 control potential in the infected cells (in vitro) and expression of other chemokines in the supernatant and in the infected cells with L. interrogans but not activated with MCP-1. The expression of chemokines will be analyzed using molecular tests (qPCR) and/or ELISA. The genes of bacteria infecting the cells will be assessed by amplification of specific genes of L. interrogans by molecular test (qPCR). The information obtained in this study could be essential to clarify the role of CCL2 and other possible chemokines on controlling the infection, or, if the expression in high levels, accelerate the host damage tissue from leptospirosis. In addition, this study can also contribute to further investigation in the search for new alternatives for the treatment of disease. (AU)

Scientific publications

(4)

(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)

DOMINGOS, R. H.; PAVANEL, E. B.; NAKAJIMA, E.; SCHONS-FONSECA, L.; DA COSTA, R. M. A.; DE FRANCO, M.; CARVALHO, E.; HO, P. L.; MARTINS, E. A.; DA SILVA, J. B.. Resistance of mice to Leptospira infection and correlation with chemokine response. Immunobiology, v. 222, n. 11, p. 1004-1013, NOV 2017. (13/16451-1)

DA SILVA, PALOMA L.; LAURETTI-FERREIRA, FABIANA; DE LIMA, MAIARA CALDAS; LIMA, SWIANY SILVEIRA; COVARRUBIAS, AMBART E.; DE FRANCO, MARCELO; CARVALHO, ENEAS; HO, PAULO LEE; DA COSTA, RENATA M. A.; MARTINS, ELIZABETH A. L.; et al. Phagocytosis of Leptospira by leukocytes from mice with different susceptibility to leptospirosis and possible role of chemokines. BMC Microbiology, v. 19, JAN 7 2019. (13/16451-1)

MARTINS-PINHEIRO, MARINALVA; SCHONS-FONSECA, LUCIANE; DA SILVA, JOSEFA B.; DOMINGOS, RENAN H.; SANTOS MOMO, LEONARDO HIROYUKI; QUIRINO SIMOES, ANA CAROLINA; HO, PAULO LEE; DA COSTA, RENATA M. A.. Genomic survey and expression analysis of DNA repair genes in the genus Leptospira. Molecular Genetics and Genomics, v. 291, n. 2, p. 703-722, APR 2016. (09/17123-2, 10/51365-0, 13/16451-1)

SILVA, PALOMA L. D.; NAKAJIMA, ERIKA; DA COSTA, RENATA M. A.; HO, PAULO LEE; MARTINS, ELIZABETH A. L.; CARVALHO, ENEAS; DA SILVA, JOSEFA B.. Chemokine expression profiles in liver and kidney of mice with different susceptibilities to leptospirosis. Microbial Pathogenesis, v. 149, DEC 2020. (13/16451-1, 17/20903-6)