Profile
After doing my M.Sc. and Ph.D. degrees from Jawaharlal Nehru University, New Delhi, specializing in Life Sciences, I gained research experience at the Laboratory of Immunology, NIAID, NIH, Bethesda, USA, and currently hold a faculty position at NII. I am actively involvement in national level committees and professional societies. During my doctoral studies, I delved into the genomic intricacies of the extrachromosomal ribosomal DNA (rDNA) circle of Entamoeba histolytica, elucidating DNA fragment sequence organization, revealing short repeat sequences proximal to rRNA genes, and uncovering novel genes. Subsequently, in my post-doctoral training, I made significant contributions to immunology, particularly in the realm of B cell biology and antibody diversification, elucidating mechanisms governing B cell repertoire maintenance, diversification, and antibody generation, thereby offering valuable insights into immune responses. Now, as an independent investigator, my research focuses on B-cell biology, monoclonal antibodies, pathogen-immune cell interactions, and host immune responses, thereby enriching our comprehension of immune response mechanisms. My notable publications encompass studies on antibody responses against Streptococcus pneumoniae and the immunomodulatory properties of bacterial components. Through our research program we hope to translate immunological discoveries into practical solutions for infectious diseases.
Current Focus Areas
Our laboratory has developed PCR-based methods to amplify immunoglobulin variable region genes from B lymphocytes. This facilitates comprehensive examination of B cell repertoires, revealing diverse heavy chain gene patterns and maturation processes. We aim to advance understanding of B-cells and develop targeted monoclonal antibody therapies.
Our research focuses on pneumococcal infections. Our studies on extracellular vesicle-associated nucleases shed light on how Streptococcus pneumoniae evades the immune system. We analyzed the immunomodulatory properties of pneumococcal capsular polysaccharide. Through these efforts we hope to understand pathogen-immune cell interactions and host immune responses, crucial for developing therapeutic interventions.
Selected Publications
Rohatgi S, Ganju P and Sehgal D (2008) Systematic design and testing of nested (RT-)PCR primers for specific amplification of mouse rearranged/expressed immunoglobulin variable region genes from small number of B cells. J Immunol Methods. 339: 205-19.
Rohatgi S, Dutta D, Tahir S and Sehgal D (2009) Molecular dissection of antibody responses against Pneumococcal surface protein A: Evidence for diverse ‘DH-less’ heavy chain gene usage and avidity maturation. J Immunol. 182: 5570-85.
Khan N, Qadri RA and Sehgal D (2015) Correlation between in vitro complement deposition and passive mouse protection of anti-Pneumococcal surface protein A monoclonal antibodies. Clin Vaccine Immunol. 22: 99-107.
Jhelum H, Sori H and Sehgal D (2018) A novel extracellular vesicle-associated endodeoxyribonuclease helps Streptococcus pneumoniae evade neutrophil extracellular traps and is required for full virulence. Sci Rep. 22: 7985.
Kaushal N, Kumari S, Jhelum H and Sehgal D (2020) In vitro and in vivo characterization of the interaction, proinflammatory, immunomodulatory and antigenic properties of capsular polysaccharide from Streptococcus pneumoniae serotype 1. Int J Biol Macromol. 143: 521-32.