Recombinant LipL32 and LigA from Leptospira are unable to stimulate protective immunity against leptospirosis in the hamster model

• Published in: Vaccine Vol. 29; no. 18; pp. 3413 - 3418
• Main Authors: Deveson Lucas, Deanna S, Cullen, Paul A, Lo, Miranda, Srikram, Amporn, Sermswan, Rasana W, Adler, Ben
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 18.04.2011; Elsevier
• Subjects: Adjuvants, Immunologic - pharmacology; Allergy and Immunology; Aluminum Hydroxide - pharmacology; animal models; Animals; Antibody Formation; Antigens, Bacterial - immunology; Applied microbiology; Bacterial Outer Membrane Proteins - immunology; Bacterial Proteins - immunology; Bacterial Vaccines - immunology; Bacteriology; Biological and medical sciences; carbohydrate structure; Cricetinae; Disease Models, Animal; Fundamental and applied biological sciences. Psychology; hamsters; humans; immune response; Immunity; Leptospira interrogans; Leptospira interrogans - immunology; Leptospira spp; leptospirosis; Leptospirosis - immunology; Leptospirosis - prevention & control; LigA; LipL32; lipopolysaccharides; lipoproteins; Lipoproteins - immunology; Microbiology; Miscellaneous; outer membrane proteins; Recombinant Fusion Proteins - immunology; serotypes; vaccines; Vaccines, antisera, therapeutical immunoglobulins and monoclonal antibodies (general aspects); LigA; LipL32; Immunity; Leptospira spp; Immunoprotection; Leptospirosis; Spirochaetales; Rodentia; Infection; Vertebrata; Mammalia; Spirochaetosis; Leptospiraceae; Bacteriosis; Bacteria; Models; Hamster; Leptospira
• ISSN: 0264-410X; 1873-2518
• DOI: 10.1016/j.vaccine.2011.02.084

Abstract The major antigenic component of pathogenic Leptospira spp. is lipopolysaccharide (LPS). However, due to the specificity of the immune response generated towards LPS and the diversity in leptospiral LPS carbohydrate structure, current commercial vaccines stimulate protection only against homologous or closely related serovars. Vaccines that confer heterologous protection would enhance protection in vaccinated animals and reduce transmission to humans. Several studies have investigated the potential of various leptospiral outer membrane proteins to stimulate protective immunity against pathogenic Leptospira species. These include the surface-exposed lipoproteins LipL32 and LigA. However, consistent protection from infection has proved difficult to reproduce. In this study we assessed the protective capacity of recombinant LipL32, the six carboxy-terminal unique Ig-like repeat domains of LigA (LigANI) and a LipL32–LigANI fusion protein in hamsters against infection with Leptospira interrogans serovar Manilae. Despite all of the proteins eliciting antibody responses, none of the hamsters was protected against infection.