Potencial imunomodulador da lectina de Canavalia brasiliensis em modelos de infecção causadas por Listeria monocytogenes

Abstract

Listeriosis is an infectious disease transmitted by food contaminated with the bacterium Listeria monocytogenes, which can cause miscarriages and miningoencephalitis in animals and humans. Antibiotics are not always effective in controlling the disease, so the use of immunotherapeutics becomes an interesting strategy to combat the disease. Conbr lectin, for example, extracted from the seeds of the Canavalia brasiliensis (Brave-Fava beans) has immunomodulatory, antimicrobial and cicatrizant activities already reported in the literature. The objective of this study was to evaluate the potential of the ConBr lectin as an immunotherapeutic in the control of L. monocytogenes infection. For this, in vitro tests with culture of macrophages treated with the lectin and infected by L. monocytogenes were carried out in order to evaluate: lectin cytotoxicity (ConBr); quantify intracellular bacteria and survival of macrophages through infection. In vivo assays were also performed to investigate the influence of ConBr lectin on the clearance of L. monocytogenes from the liver and spleen and quantification of leukocytes present in the blood of experimental animals. The results showed that the lectin produced an antiinflammatory stimulus in the animals that was negative for the elimination of the L. monocytogenes bacterium, as well as reduced the total leukocyte count when compared to the control group. It was concluded that, although ConBr lectin did not contribute to the control of L. monocytogenes infection, there is potential for the control of inflammatory processes derived from systemic infections.