Identificação de peptídeos potenciais candidatos para desenvolvimento de vacina contra Leptospirose

Abstract

Leptospirosis is caused by bacteria of the genus Leptospira. More than 500,000 severe cases are reported annually, with a mortality rate of over 10%. Infection in humans usually occurs through direct or indirect contact with the urine of carrier animals. Reservoir animals do not present clinical signs of the acute disease, but renal colonization by Leptospira is frequent. Leptospirosis affects populations in both urban and rural areas, especially in tropical and subtropical climates areas. Conditions such as heavy rainfall and areas without sanitary services, favor the incidence and spread of leptospirosis. Humans are accidental hosts and may have asymptomatic manifestations or severe disease leading to death. The Leptospira genus harbors a wide variety of serovars, hindering the development of vaccine and early diagnosis, and consequently the control of the disease. The aim of this study was to identify Leptospira protein peptides conserved with immunogenic potential and capacity for recognition by antibodies present in human sera from diagnosed patients with leptospirosis. For this, five peptides were designed and selected in silico and analyzed by Dot-blot technique. The results demonstrated the five peptides were recognized by antibodies from human serum. The Pep 9 was recognized by two sera samples. In this study, the immunoinformatics tools were important to help in the peptides screening, and optimizing time and reducing financial expenses. The Dot-blot technique indicate to be effective for testing the recognition of epitopes that may induce an immune system response. The identification of peptides that are recognized by antibodies is a promising approach for the development of vaccines and diagnostic method for leptospirosis.