In vitro evaluation of putative lectin activity from Paracoccidioides brasiliensis on adaptive immunity events

• Grant number: 16/16034-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2016
• End date: September 30, 2017
• Field of knowledge: Biological Sciences - Immunology - Cellular Immunology
• Principal Investigator: Fabrício Freitas Fernandes
• Grantee: Marcia de Almeida
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Lectins are a class of carbohydrate binding proteins, which show high potential for therapeutic and biotechnological applications. Fungal lectins have attracted great interest due to antitumor, immunomodulatory, and antiproliferative activities. Although, commonly the fungal lectins have not been characterized and expressed in recombinant form, fact that is essential to evaluate the therapeutic potential of fungal lectins. In this context, the cloning, expression, and purification of fungal lectins are necessary. Our group has been developing studies with pathogens lectins, as Paracoccin, which is obtained from Paracoccidioides brasiliensis. It is known that P. brasiliensis and P. lutzii cause the paracoccidioidomycosis (PCM), which is characterized as systemic mycosis. The clinical forms of PCM varies depending of host immune response. The high incidence of PCM cases in Brazil, the severity of the clinical condition, and the high toxicity of antifungal, are factors that explain the importance of studies to identify new molecules that can act in resolving the PCM. In this sense, we identified two possible lectins from P. brasiliensis and we intend to investigate the biological activities of these proteins. Therefore, we propose the cloning and expression of putative proteins PADG_07152 and PADG_01036 from P. brasiliensis employing the expression system in Pichia pastoris. Afterwards, the characterization of biological activities of PADG_07152 and PADG_01036 from P. brasiliensis will be evaluated their effects on murine adaptive immunity cells. This study will help to identify new molecules as therapeutic tools against PCM. Besides, the study of lectins from P. brasiliensis opens perspectives to identify other biological activities, as antitumor and antiproliferative activity, performed by different lectins already known and well characterized. (AU)