Recombinant Gene Products
Research Interests and Description
Group Leader: Navin Khanna, PhD
Genetically engineered biomolecules of medical use, subunit dengue vaccines, dengue reporter viruses, anti-dengue herbals, RNAi, codon-shuffling, pathogenesis of dengue and tuberculosis.
Description of Research
Genetically engineered biomolecules and viral diagnostics
Current research focuses on genetically engineered biomolecules of medical use. A primary contribution is in the development of novel recombinant designer proteins as inexpensive, highly sensitive and specific diagnostic intermediates for viral infections, such as HCV, HIV and Dengue virus. The availability of high quality diagnostic intermediates for HCV, HIV and HBV from our laboratory to manufacturers of diagnostic kits has reduced production costs significantly. These kits are being manufactured in India and are being used in several Asian and African countries.
In collaboration with Prof. Kim Pettersson, University of Turku, Finland, these designer proteins are being explored for developing novel reporter assays using Terbium-labelled nanoparticles. Work is underway to create a unique 3-in-1 assay for the simultaneous detection of HIV, HBV and HCV infections, for use in blood bank settings. Based on our diagnostic intermediates, a test has been commercialized for the detection of dengue NS1 antigen from all 4 dengue serotypes. This kit has been launched in 2010 and has been a great success on the Indian market.
In collaboration with Prof. Ursula Rinas, Helmholtz Institute of Infection Research, Germany, we have used our HBsAg clone to design a robust high cell density protocol capable of yields as high as ~7 g/L culture broth. Recently, our lab-scale technology to produce HBsAg in the yeast has been transferred to a company in China. This high cell density cultivation process, extended to a tri-party collaboration with ICGEB Trieste, has resulted in the secretion of insulin precursor to 3g/L culture broth, and this newly developed know-how for high-level secretion of rh-Insulin has been transferred to China.
Recombinant dengue vaccine development
Four serotypes of Dengue viruses (DENV-1, -2, -3 and -4) cause Dengue disease, for which there is currently no vaccine or antiviral drug. The RGP Group is interested in developing sub-unit vaccines, based on DENV envelope domain III, which mediates virus entry into cells and elicits virus-neutralizing antibodies. At present, our research activities are focused towards the development of experimental Dengue tetravalent subunit vaccine in yeast. In consultation with the Indo-US Vaccine Action Program, we have created DENV-2 EDIII HBsAg virus-like particles (VLPs) and are currently evaluating these physically and functionally.
Synthesis and selection of de novo antibacterial proteins
Current efforts are directed towards extending the previously developed codon-shuffling method to create antibacterial proteins against pathogenic organisms, such as Mycobacterium tuberculosis, focussing on some essential proteins from this pathogen. During our efforts to isolate potential binding partners of key secretory proteins of M. tuberculosis from a human lung protein library, we isolated peptides that strongly bound the virulence determinant protein Esat6. We have also initiated studies towards finding potent binders and inhibitors of some selected proteins of DENV-2.
Sood, R., Raut, R., Tyagi, P., Pareek, P.K., Barman, T.K., Singhal, S., Shirumalla, R.K., Kanoje, V., Subbarayan, R., Rajerethinam, R., Sharma, N., Kanaujia, A., Shukla1, G., Gupta, Y.K., Katiyar, C.K., Bhatnagar, P.K., Upadhyay, D.J., Swaminathan, S., Khanna, N. 2015. Cissampelos pareira Linn: Natural Source of Potent Antiviral Activity against All Four Dengue Virus Serotypes PLoS NTD (In Press)
Talha, S.M., Juntunen, E., Salminen, T., Sangha, A., Vuorinen, T., Khanna, N., Pettersson, K. 2015. All-in-one dry-reagent time-resolved immunofluorometric assay for the rapid detection of HIV-1 and -2 infections. J Virol Methods 226, 52-59 PubMed link
Tripathi, L., Mani, S., Raut, R., Poddar, A., Tyagi, P., Arora, U., de Silva, A., Swaminathan, S., Khanna, N. 2015. Pichia pastoris-expressed dengue 3 envelope-based virus-like particles elicit predominantly domain III-focused high titer neutralizing antibodies. Front Microbiol 6, 1005 PubMed link
Sharma, C., Sankhyan, A., Sharma, T., Khan, N., Chaudhuri, S., Kumar, N., Bhatnagar, S., Khanna, N., Tiwari, A. 2015. A repertoire of high-affinity monoclonal antibodies specific to S. typhi: as potential candidate for improved typhoid diagnostic Immunol Res 62, 325-340 doi: 10.1007/s12026-015-8663-z PubMed link
Beesetti, H., Khanna, N., Swaminathan, S. 2014. Drugs for dengue: a patent review Expert Opin Ther Pat 24, 1171-1184 PubMed link
Talha, S.M., Hytönen, J., Westhorpe, A., Kumar, S., Khanna, N., Pettersson, K. 2013. Europium nanoparticle based high performing immunoassay for the screening of treponemal antibodies. PLoS One 8 PubMed link
P.K. Bhatnagar, C. K. Katiyar, N. Khanna, D. J. Upadhyay, S. Swaminathan, K. Srinivas, N. Sharma, A. Kanaujia, R. Sood, S. Singhal, G. Shukla, R. Duggar, P. K. Pareek, Y. Singh, S. Khan, and R. Raut. Anti-dengue activity of Cissampelos pariera extracts. US 2012/0107424 A1
P.K. Bhatnagar, C. K. Katiyar, N. Khanna, D. J. Upadhyay, S. Swaminathan, K. Srinivas, N. Sharma, A. Kanaujia, R. Sood, S. Singhal, G. Shukla, R. Duggar, P. K. Pareek, Y. Singh, S. Khan, and R. Raut. Anti-dengue activity of Cissampelos pariera extracts. EP2389184
P.K. Bhatnagar, C. K. Katiyar, N. Khanna, D. J. Upadhyay, S. Swaminathan, K. Srinivas, N. Sharma, A. Kanaujia, R. Sood, S. Singhal, G. Shukla, R. Duggar, P. K. Pareek, Y. Singh, S. Khan, and R. Raut. Anti-dengue activity of Cissampelos pariera extracts. CN102361644 (A)