Research Interest:
Our group works in the area of virus immunology. The goal is to identify the determinants of long-lasting protective humoral immunity. Major emphasis is on understanding the biology and traits of CD4+ follicular T helper (Tfh) cells that are indispensable for the generation of germinal center derived humoral immunity. The long-term goal is to identify and harness the positive attributes of Tfh cells for rational designing of vaccines.
Summary of Research:
Our lab works at the interface of fundamental and translational immunology. Tfh cells are a specialized subset of CD4+ T cells that provide help to B cells and devise the magnitude and quality of germinal-center derived antibodies. In the last two decades, the factors that govern Tfh cells differentiation and the unique role of Tfh cells in the establishment of humoral immunity have been extensively studied. However, more needs to be learned about the cues that lead to the generation of potent Tfh cells in long-lasting and broadly protective humoral immunity. Certainly, this knowledge will be phenomenal for vaccine development. Therefore, our attempts are focused on resolving the traits and function of Tfh cells in long-term sustained immunity. We study Tfh cells in the settings of immunological memory acquired after virus infection or human vaccination. We are integrating viral immunology, deep immunophenotyping, single-cell genomics, and metabolomics approaches to investigate the biology of Tfh cells in two different models - (i) Human vaccination. Here, we are studying the characteristics and clonotypic diversity of human Tfh cells established in response to licensed human vaccines like SA14-14-2 Japanese encephalitis (JE) vaccine, SARS-CoV-2 vaccines etc. To identify the ideal attributes of Tfh cells in long-term immunity, we are studying the function and traits of Tfh cells induced in vaccination to that of natural infection. To do this, we have established longitudinal cohorts of controlled vaccination and virus infection. Besides, we are also using ex vivo Tfh model and mouse models to mechanistically investigate the leads generated from our human studies. (ii) Human virus infection. In this program, our attempts are focused on providing insight into the immunological memory and T-cell determinants of humoral responses to viruses like Dengue virus. Here, we are exploring the biology of Tfh cells and related CD4+ T-cell subsets at a greater depth in patients with diverse outcomes of virus infection.
Group Members:
Asgar Ansari, Bhushan Nikam, Someshwar Nath Jha, Suvechchha Pandit, Bhanu Pratap Singh (PhD scholars); Sathi Mallick (Postdoctoral fellows); Yatish Thakarey, Asha Kushwaha (Project staff); Sudipta Das, Inderjit Singh (Technical officers)
Awards:
• 2022: Mid-Career Immunologist Oration Award by the Indian Immunology Society for the contribution in the area of “T cell immunity to vaccines”
• 2021: Young Scientist award, India International Science Festival-2020
• 2020: Early Career Faculty Award by American Association of Immunology
• 2019: The Merieux Foundation Fellowship for the Advancement in Vaccinology
• 2016: Martin Villar Award
• 2016: Ramalingaswami Fellowship
• 2016: Global Health Travel Award of Bill and Melinda Gates Foundation
• 2013: European Federation of Immunological Societies Young Investigator Award
• 2013: International Society of Thrombosis & Haemostasis Young Investigator Award
• 2008: Raman-Charpak Fellowship, Institute Pasteur, Paris, France
• 2008-2010: Brig. K.M. Rao Award, Defence R&D Establishment, India
Funding:
Department of Biotechnology, Department of Science and Technology (SERB), NER-BPMC Twinning Program (DBT), Ramalingaswami Fellowship, Indo-USA Human Immunophenotyping Consortium, National Biopharma Mission Dengue Consortium (BIRAC), National Biopharma Mission COVID-19 Consortium (DBT-BIRAC), Intensification of Research in High Priority Areas (DST).
Patents:
• 202211046391 (Indian Patent): A dengue virus follicular T helper (Tfh) cell specific peptide megapool and its use thereof.
• WO2017/012959: Methods and pharmaceutical compositions for inducing immune tolerance by mucosal vaccination with Fc-coupled antigens.
• US62/188,004: Prenatal therapy to induce immune tolerance.
• 202111003148 (Indian Patent) - A novel method to evaluate the quality of antigen-specific T cells in infection and vaccination.