Screen Reader Access   

People : Scientific : Faculty & Scientists


Senior Scientist
+91-129-2876306  (9540278405)
supratik [at] thsti [dot] res [dot] in
Ph.D., Albert Einstein College of Medicine, USA

Research Interests

Generating a soluble, trimeric, cleaved envelope (Env) immunogen is a significant challenge towards developing an effective vaccine against HIV-1. The mature Env spike is composed of a trimer of the gp120 and gp41 heterodimer that are non-covalently associated. It has been recently shown that trimeric gp140 elicits more potently neutralizing antibodies than monomeric gp120. Although, the gp140 trimer showed high affinity binding to CD4bs bNAbs VRC01 and CH31 and no binding to the non-neutralizing CD4 BS antibody b6, it is likely that, due to its structure, epitopes that are occluded in the native Env spike will be exposed in these immunogens resulting in non-neutralizing antibody responses in addition to NAbs. Therefore, further improvements are required in developing Env immunogens that closely resemble the native, oligomeric Env spike. Proteolytic processing of the HIV-1 gp160 Env glycoprotein is essential for infectivity of the virus. The precursor gp160 is processed under normal conditions into the mature gp120 (HIV-1 SU) and gp41 (HIV-1 TM) subunits. The major site (site 1) of cleavage at the gp120-gp41 junction is R-E-K-R which results in an oligomeric gp41. Previous studies have demonstrated that efficient precursor cleavage is essential for selective recognition of oligomeric Env by potently neutralizing antibodies. Env from different primary isolates are processed differently and there is a positive correlation between efficient precursor cleavage and neutralization potency. Finally, the gp120 and gp41 non-covalent association in the mature, native spike is very labile making it unsuitable for vaccine development. In previous studies, researchers have attempted to introduce disulphide bonds between gp120 and gp41 in order to develop more stable gp120/gp41 heterodimers. The overall aim of my research is to develop Env immunogens that are trimeric and cleaved but soluble, monodisperse and stable to be used as candidate subunit vaccine.

Fellowships/Assistantships/Travel Awards

  • Junior Research Fellowship by the University Grants Commission (Government of India) in 1993.
  • Graduate Research Assistantship by Albert Einstein College of Medicine, USA in 1994.
  • SRA (Scientist’s pool scheme) Fellowship by the Council for Scientific and Industrial Research, India in 2009.
  • HIVR4P Meeting Travel Scholarship in 2016

Research Articles

  • Samal S, Bansal M, Das SMethod to identify efficiently cleaved, membrane-bound, functional HIV-1 (Human Immunodeficiency Virus-1) envelopes. MethodsX (Elsevier) 2019 6:837-849.
  • Das S@, Bansal M, Bhattacharya J Characterization of the membrane-bound form of the chimeric, B/C recombinant HIV-1 Env, LT5.J4b12C. J Gen Virol 2018 99 (10): 1438-1443. 
  • Samal S*, Das S*, Boliar S, Qureshi H, Shrivastava T, Kumar N, Goswami S, Bansal M, Chakrabarti BK. (*Co-First Author) Cell surface ectodomain integrity of a subset of functional HIV-1 envelopes is dependent on a conserved hydrophilic domain containing region in their C-terminal tail. Retrovirology 2018, 15:50.
  • Das S, Boliar S, Samal S, Ahmed S, Shrivastava T, Shukla BN, Goswami S, Bansal M, Chakrabarti BK. Identification and characterization of a naturally occurring, efficiently cleaved, membrane-bound, clade A HIV-1 Env, suitable for immunogen design, with properties comparable to membrane-bound BG505. Virology 2017; 510:22-28.

  • Das S, Boliar S, Mitra N, Samal S, Bansal M, Koff WC, Chakrabarti BK Membrane bound modified form of clade B Env, JRCSF is suitable for immunogen design as it is efficiently cleaved and displays all the broadly neutralizing epitopes including V2 and C2 domain-dependent conformational epitopes Retrovirology 2016; 13:81.
  • Boliar S*, Das S*, Bansal M, Shukla BN, Patil S, Shrivastava T, Samal S, Goswami S, King CR, Bhattacharya J, Chakrabarti BK (*Co-First Author) An efficiently cleaved HIV-1 clade C Env selectively binds to neutralizing antibodies PLOS One 2015; 10(3): e0122443.
  • Das S@, Banerjee B, Hossain M, ThangamuniyandiM, Dasgupta S, Chongdar N, Kumar GS, Basu G Characterization of DNA binding property of the HIV-1 host factor and tumor suppressor protein Integrase Interactor 1 (INI1/hSNF5) PLOS One 2013; 8(7):e66581 
  • Biswas A, Mukherjee S, Das S, Shields D, Chow CW, Maitra U. Opposing action of casein kinase 1 and calcineurin in nucleo-cytoplasmic shuttling of mammalian translation initiation factor eIF6.  J Biol Chem 2011; 286(4):3129-3138.
  • Das S, Kalpana GV. Reverse Two-hybrid Screening to Analyze Protein-Protein Interaction of HIV-1 Viral and Cellular Proteins. Methods in Molecular Biology 2009; 485: 271-293.
  • Das S, Cano J, Kalpana GV Multimerization and DNA binding properties of INI1/hSNF5 and its functional significance. J Biol Chem 2009; 284(30):19903-19914.
  • Sorin M*, Cano J*, Das S, Mathew S, Wu X, Davies KP, Shi X, Cheng GS, Ott D, Kalpana GV. (*Co-First Author) Recruitment of a SAP18-HDAC1 complex into HIV-1 virions and its requirement for viral replication. PLOS Pathogens 2009; 5(6) e1000463.
  • Foletta VC, Lim MA, Soosairaiah J, Kelly AP, Stanley EG, Shannon M, He W, Das S, Massague J, Bernard O. Direct signaling by the BMP type II receptor via the cytoskeletal regulator LIMK1. J Cell Biol 2003; 162(6):1089-1098.
  • Das S, Ghosh R, Maitra U. Eukaryotic translation initiation factor 5 functions as a GTPase-activating protein. J Biol Chem. 2001; 276(9):6720-6726.
  • Das S, Maitra U. Mutational analysis of mammalian translation initiation factor 5 (eIF5): role of interaction between the beta subunit of eIF2 and eIF5 in eIF5 function in vitro and in vivo. Mol Cell Biol. 2000; 20(11):3942-3950.
  • Maiti T*, Das S*, Maitra U. (*Co-First Author) Isolation and functional characterization of a temperature-sensitive mutant of the Yeast Saccharomyces cerevisiae in translation initiation factor eIF5: an eIF5- dependent cell-free translation system. Gene 2000; 244(1-2):109-118.
  • Das S, Maiti T, Das K, Maitra U. Specific interaction of eukaryotic translation initiation factor 5 (eIF5) with the beta-subunit of eIF2. J Biol Chem 1997; 272(50):31712-31718.


Books/Book Chapters /Reviews 

  • Das STowards a HIV Vaccine: Biology, Progress and Challenges Scholars’ Press, SIA OmniScriptum Publishing 2018; ISBN-13: 978-620-2-30940-0. Book

  • Das S@ Integrase interactor 1 in health and disease Current Protein and Peptide Science 2015; 16(6):478-490. Review
  • Das S, Maitra U. Functional significance and mechanism of eIF5-promoted GTP hydrolysis in eukaryotic translation initiation. Prog Nucleic Acid Res Mol Biol 2001; 70:207-231. Review/Book chapter.


@ Corresponding Author