Journal of Vaccines & Vaccination

Heat-killed multi-serotype Shigella immunogens induced humoral and cell mediated immunity and protection in animal models

8^th Indo Global summit and Expo on Vaccines, Therapeutics & Healthcare

November 02-04, 2015 HICC, Hyderabad, India

Dhrubajyoti Nag, Ritam Sinha, Sumio Shinoda and Hemanta Koley

National Institute of Cholera and Enteric Diseases, India

Posters-Accepted Abstracts: J Vaccines Vaccin

Abstract:

Bacillary dysentery caused by Shigella species, is a major reason of infant morbidity and mortality in developed as well as in developing countries. In our present study, we have developed a heat-killed multi-serotype Shigella (HKMS) immunogens from six sero-groups of shigellae. After three successive oral immunizations with HKMS immunogens in rabbit model, serum and lymphocyte supernatant antibody titer against the heterologous shigellae were reciprocally increased and remained at an elevated level up to 180 days. Serogroup and serotype specific O-antigen of lipopolysaccharide and immunogenic proteins of heterologous challenge strains were detected by immunoblot assay. HKMS-specific plasma cell response was confirmed by production of a relatively higher level of HKMS-specific IgG in immunized PBMC supernatant compared to control group. To check the cell mediated immune responses in mice we have immunized mice; peritoneal macrophages, bone marrow derived dendritic cell (BMDC) and CD4+ T-cells were isolated from immunized and non-immunized mice on different time interval after immunization. Production of nitric oxide from peritoneal macrophages and different cytokines such as IL-12p70, IL-1β, IL-6 and IL-23 from BMDC of non-immunized mice treated with HKMS immunogens confirmed the immunogens induced innate and adaptive immune responses. Incubation with HKMS immunogens with HKMS-primed splenic CD4+ T cells enhances the production of IFN-γ, IL-10 and IL-17 represented HKMS immunogens may induce Th1 and Th17 cellmediated immune responses. Furthermore, the immunized groups of animals exhibited complete protection against wild type heterologous shigellae challenge. This immunogen could be a broad spectrum non-living vaccine candidate for human in the near future.

Biography :

Dhrubajyoti Nag has completed his MSc in 2011 in Biotechnology from Jadavpur University. From 2011, he has been working as a research fellow in National Institute of Cholera and Enteric Diseases (ICMR), Kolkata. Mainly he is working on vaccine development against shigellosis. He has been working on different forms of Shigella immunogen and investigating their immunogenicity and protective efficacy in different animal models. He has published 11 original papers as first author and also as co-author in international prestigious journals.

Email: nagdhrubajyoti@gmail.com