Evaluation of the interaction of Leptospira interrogans proteins with host components by constructing recombinant Leptospira biflexa

• Grant number: 18/09652-4
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: September 01, 2018
• End date: November 30, 2022
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Ana Lucia Tabet Oller do Nascimento
• Grantee: Leandro Toshio Kochi
• Host Institution: Instituto Butantan. Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Associated research grant: 14/50981-0 - Search for surface proteins among the genome sequences of Leptospira interrogans: functional and immunological characterization to understanding mechanisms involved in the bacterial pathogenesis, AP.TEM

Abstract

Leptospirosis is an acute infectious disease of worldwide importance and considered as one of the neglected tropical diseases. The disease is caused by pathogenic bacteria of the genus Leptospira and affects several mammals, including man. To date, there is no effective vaccine against the disease, which is of major socioeconomic importance in tropical developing countries. The fight against leptospirosis becomes more difficult since the biology of the pathogen is not yet fully understood. Several research groups seek to better understand the mechanisms of pathogenicity and development of an effective vaccine by screening potential candidates, which are generally outer membrane proteins conserved in different pathogenic leptospire species. This characterization is generally done through the expression and purification of recombinant proteins, which often may not mirror what occurs in vivo. Thus, developing recombinant strains has been a viable alternative. In this sense, the present project proposes the construction of L. biflexa (saprophytic) recombinant strains expressing the proteins of interest, encoded by the L. interrogan genes LIC11711 and LIC12587, whose recombinant counterparts demonstrated significant interactions with host components in vitro . The expression of the proteins in the saprophytic strain will allow the functional validation of these as possible ligands to components of the host and the understanding of the roles in the mechanisms of pathogenicity and possible vaccine candidates. Initially, constructs will be made using the plasmid pMaOri and the genes of interest, previously fused with the promoter of the lipL32 gene. L. biflexa will be transformed with the plasmid constructs for expression of the proteins. Cell localization assays and interaction assays of recombinant L. biflexa with host components will be performed. Hamsters will be immunized with the recombinant proteins or the recombinant bacteria and challenged for evaluation of the immune protection provided by these vaccine elaborations.

Scientific publications

(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)

KOCHI, LEANDRO TOSHIO; FERNANDES, LUIS GUILHERME VIRGILIO; NASCIMENTO, ANA LUCIA TABET OLLER. Heterologous Expression of the Pathogen-Specific LIC11711 Gene in the Saprophyte L. biflexa Increases Bacterial Binding to Laminin and Plasminogen. PATHOGENS, v. 9, n. 8, AUG 2020. (18/09652-4, 17/06731-8, 14/50981-0)

TEIXEIRA, ALINE F.; CAVENAGUE, MARIA F.; KOCHI, LEANDRO T.; FERNANDES, LUIS G.; SOUZA, GISELE O.; DE SOUZA FILHO, ANTONIO FRANCISCO; VASCONCELLOS, SILVIO A.; HEINEMANN, MARCOS BRYAN; NASCIMENTO, ANA L. T. O.. Immunoprotective Activity Induced by Leptospiral Outer Membrane Proteins in Hamster Model of Acute Leptospirosis. FRONTIERS IN IMMUNOLOGY, v. 11, OCT 30 2020. (14/50981-0, 17/06731-8, 18/09652-4, 18/08131-0, 16/11541-0)

DAROZ, BRENDA B.; FERNANDES, LUIS G. V.; CAVENAGUE, MARIA F.; KOCHI, LEANDRO T.; PASSALIA, FELIPE J.; TAKAHASHI, MARIA B.; NASCIMENTO FILHO, EDSON G.; TEIXEIRA, ALINE F.; NASCIMENTO, ANA L. T. O.. A Review on Host-Leptospira Interactions: What We Know and Future Expectations. FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY, v. 11, p. 13-pg., 2021-11-25. (18/06201-1, 18/08131-0, 17/01102-2, 17/26223-7, 16/11541-0, 18/09652-4, 18/21959-8, 19/17488-2, 17/06731-8)