Megha Kadam Bedekar
Central Institute of Fisheries Education, India
Megha Kadam Bedekar completed Bachelor of Veterinary Science degree in 1999, and secured gold medal for best thesis research work for Master's degree. She completed PhD in Animal Biotechnology from Indian Veterinary Research Institute and joined Animal Biotechnology Centre, Jawaharlal Nehru Veterinary University, Jabalpur India, as Assistant Professor in 2005. In 2011 she got selected as Senior Scientist in Central Institute of Fisheris Education, Mumbai. Her areas of specialization are animal biotechnology, immunology, and microbiology. She developed PCR based diagnosis system and database of Infectious bronchitis virus strains of India and novel vaccine construct against Mycobacterium avium paratuberculosis. Currently, she is working on development of bicistronic vaccines against important bacterial diseases of aquatic animals.
Economics of fish farming industry is severely affected with problems due to a variety of infectious agents that includes both bacterial and viral pathogens. Immune system of fishes is less developed compared to higher vertebrates. Therefore responsibility of the fisheries scientists is more towards development of better vaccination strategy that can activate both specific and non-specific immune response.Interferon gamma (IFNγ) is the key cytokine which activate inflammatory and Th1 subset of immune response against bacterial and viral diseases.Addressing to the important role of IFNγwe have cloned and studied the effect of rIFNγ on immune system of labeorohita, which is one of the most economically important fresh water carp in India. We have cloned and expressed 551 bpIFNγ open reading frame of Labeorohita in SSN-1 cell line using eukaryotic expression vector system. The SSN-I cell linewas transfected and at 24h and 48h post-transfection, 18.7kDAIFNγ protein was expressed in these cells, which was confirmed by Western blot with anti-his antibodies. This IFNγ construct was also transfected in peripheral blood lymphocytes (PBMCs) and checked for expression of four genes IFNγ, iNOS, MX and IL-1β by real-time PCR. Significantly high expression of all four genes was observed in IFNγ-treated group compared to mock transfected group at 24h and 48h time-points in terms of fold increase (p<0.05). IFNγ and iNOS showed the peak expression at 24h and remained at the same level until 48h. However, MX and IL-β1 were found to be highly up-regulated at 48h compared to 24h. The results showed the conserved function of IFNγand up-regulation of these genes indicated the role of IFNγin anti- bacterial, anti-viral and inflammatory responses. Our study highlights the candidature of IFNγ as immunoadjuvant along with vaccine against fish pathogens.