Area: Infectious Immunology and Immunopathology

In a quest to clear infections of various kinds, the host responds to the insults and induces activation of cells of innate and adaptive immune system that eradicate invading pathogens. At the same time regulatory mechanisms also operate to curtail excessive inflammatory responses. The timely induction of an adaptive immune response and its maintenance in the memory phase forms the  basis  of  lasting  protective  immunity  against  infectious  diseases  and  provides  clue  for successful vaccination. After receiving help from CD4 T cells, pathogen-specific CD8 T cells are appropriately activated to control the spread of intracellular pathogens such as viruses.  Animal models  are  used  to  investigate  host-pathogen  interaction.  For  studying  the  function  and differentiation of adaptive T and B cells, one has to secure sufficient number of antigen-specific cells in naïve state but in a normal host the frequency of T cells specific to any given antigen is very low and frustrates attempts at isolating such cells in meaningful numbers. In our laboratory we aim to  understand  the  function  and  differentiation  of  CD8  T  cells  during  infection  with  endemic pathogens  such  as  dengue  virus,  Chikungunya  virus  and  protozoan  parasites  such  as Plasmodium  in  addition  to  herpes  viruses,  the  latter  being  the  most  successful  pathogen. Employing various molecular and immunological approaches, we try to understand the host- pathogen interaction. We are also putting efforts in developing novel animal models to study immunity and immunopathology during viral infections. We welcome creative colleagues who are interested in learning and contributing to the advancement of immunology to join our group.

• Veiga-Parga T, Sehrawat S and Rouse BT (2013) Regulatory T cell function in anti-viral immunity. Immunol Reviews 255(1):182-96
• Swee KL, Guimaraes CP, Sehrawat  S, Spooner E, Brassa, I and Ploegh HL (2013) Sortase- mediated installation of antigens onto anti-DEC205 enables optimization of antigen presentation and  immunization  against  a  complex  set  of  viral  epitopes.  Proc  Natl  Acad  Science  USA 110(4):1428-33
• Sehrawat S, Koenig, PA, Kirak O, Schlieker C and Ploegh HL (2013) A catalytically inactive mutant of deubiquitylase YOD-1 enhances the antigen cross presentation. Blood 121(7):1145-56
• Sehrawat S, Kirak O, Koenig PA, Issacson MK, Marques S, Bozkurt G, Simas JP, Jaenisch R and Ploegh HL (2012). CD8⁺  T cells from mice transnuclear for a TCR that recognizes a single H-2K^b– restricted MHV68 epitope derived from gB (ORF8) help control the infection. Cell rep 1: 461-471.
• Sehrawat S* and Rouse BT (2011) Tregs and Infections: On the potential value of modifying their function? J Leukoc Biol. 90: 1079-1087.
• Rouse BT and Sehrawat S (2010) Immunity and immunopathology to viruses: What decides the outcome? Nature Rev Immunology 10, 514-526.
• Sehrawat S, Reddy PB, Rajasagi N, Suryawanshi A, Hirashima M, Rouse BT (2010) Galectin- 9/TIM-3  interaction  regulates  virus-specific  primary  and  memory  CD8  T  cell  response.  PloS Pathogens. 6 (5): e1000882
• Sehrawat S*, Suryawanshi A and Rouse BT (2009) Role of TIM-3/galectin-9 inhibitory interaction in  a  virus  induced  immunoinflammatory  lesion:  Shifting  the  balance  towards  regulators.  J Immunol. 182(5): 3191-201.
• Sehrawat  S, Suvas S, Sarangi PP, Suryawanshi, A and Rouse BT (2008) In vitro generated antigen specific CD4⁺CD25⁺Foxp3⁺  regulatory T cells control the severity of HSV-induced ocular immunoinflammatory lesion. J. Virol. 82(14): 6838-51.
• Sehrawat  S*  and  Rouse  BT  (2008)  Anti-inflammatory  effect  of  FTY720  in  a  viral  induced immunopathology: Role of drug induced conversion of CD4⁺Foxp3^– cells to become CD4⁺Foxp3⁺ T cells. J Immunol: 180(11): 7636-47.