A Conserved Region of Leptospiral Immunoglobulin-Like A and B Proteins as a DNA Vaccine Elicits a Prophylactic Immune Response against Leptospirosis

Adhesins of Leptospira interrogans Mediate the Interaction to Fibrinogen and Inhibit Fibrin Clot Formation In Vitro

“…We thus decided to investigate whether the selected surface-exposed proteins were capable of binding human Fg in vitro . Seven recombinant leptospiral proteins, expressed and purified in our laboratory, LigB7-12, used as positive control [31], [16], [17], and the negative protein controls gelatin and pneumococcal recombinant protein PspA, were individually placed onto 96-wells and incubated with previously immobilized human Fg. The binding was quantified by ELISA and the results obtained from three independent experiments are shown in Fig.…”

“…The binding of the recombinant proteins to Fg was evaluated by a modified ELISA, as follows: 96-well plates (Costar High Binding, Corning) were coated overnight in PBS at 4°C with 100 µL of 10 µg/mL of the human Fg (Sigma); LigB7-12 protein of L. interrogans , known as having Fg-binding domain [31], [17], generous donation from Dr. Odir Dellagostin, UFPEL, RS, Brazil, was employed as a positive control. PspA, an outer membrane protein of Streptococcus pneumoniae [32], kind gift from Dr. Luciana Leite, Instituto Butantan, SP, Brazil, was employed as an unrelated negative control protein.…”

Protective Immunity and Reduced Renal Colonization Induced by Vaccines Containing Recombinant Leptospira interrogans Outer Membrane Proteins and Flagellin Adjuvant

“…Previous evidence indicated that hamsters vaccinated with a combination of OmpL1 and LipL41 embedded in bacterial membranes developed protective immunity and resistance to renal colonization (11). Immunization with a DNA vaccine encoding the conserved amino-terminal regions of LigA and LigB provided partial protection, and most of the surviving animals showed sterilizing immunity (19). LigA belongs to the family of bacterial proteins characterized by the presence of immunoglobulinlike repeat domains.…”

“…Several leptospiral outer membrane proteins have been evaluated as potential vaccine antigens, including lipoproteins (LipL41 and LipL32), porin OmpL1, immunoglobulinlike proteins (LigA and LigB), and OmpA-like proteins (9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). Previous evidence indicated that hamsters vaccinated with a combination of OmpL1 and LipL41 embedded in bacterial membranes developed protective immunity and resistance to renal colonization (11).…”

Clivagem de proteínas do complexo de ataque à membrana do sistema complemento humano por proteases de leptospiras patogênicas.

“…Diferentes fragmentos da proteína LigA foram capazes de conferir 100% de proteção em modelo experimental empregando hamster. No entanto, estudos adicionais são necessários para prevenir a colonização renal, uma vez que esses animais continuaram sendo portadores da bactéria (Faisal et al, 2008;Forster et al, 2013;Palaniappan et al, 2006).…”