Vector Borne Diseases

INFECTIOUS DISEASES / Virology

Research Interests

Vector-borne diseases, arbovirus, vector biology, chikungunya virus, dengue virus, host pathogen interactions, RNAi, functional genomics

Description of Research

The current focus in the lab is on understanding chikungunya virus (CHIKV) and dengue virus (DENV) evolution and in studying the dynamics of chikungunya virus /dengue virus (CHIKV/DENV) co-infections in vector and host. With respect to CHIKV evolution, we characterize CHIKV isolated from patients over the years and study the changes in the disease pattern and the molecular characterization over the years. Our studies have paved way to understanding chikungunya disease progression and occurrence of co-infections of CHIKV with DENV in the Indian population. Recently, we identified distinct metabolites in clinical samples of chikungunya and dengue mono and co-infections. We show that distinct pathways are regulated during fever, joint pain and chronic phase of the three conditions of disease presentations.

Using genomic tools, we are identifying vector factors that may play a role on pathogen establishment within the vector with primary interests on the insect microRNA populations. Using next generation sequencing technologies, we have provided important insights to the role of microRNAs in pathogenesis and development. Currently, efforts are been made to bring in another layer of data analysis from global proteomic and metabolomics studies thereby integrating the fields of omics to understand the biology of virus-vector interactions.

We are also studying virus derived virulence factors that could be playing important roles in enabling virus to fight insect immunity. In this regard, we have shown that two non-structural proteins, namely, nsP2 and nsP3 exhibit suppressor RNAi activity in both insect and host. These proteins are the first viral RNAi suppressors to be identified in alphavirus, thereby providing new insights to underlying mechanisms for virulence in alphaviruses. Furthermore, we are also interested in identifying vector host factors that may play a role in CHIKV replication and we are using CRISPR-CAS 9 gene editing technologies for this purpose.

Our lab’s long-term research goal is evaluating the mechanism of co-infection in vector. For this purpose, we have already initiated proof of concept experiments to establish co-infections in lab reared Aedes. We have seen that initial viral load of both the viruses are important in establishing co-infections in the vector. We are currently evaluating the role of super-infections of each of the virus to decipher if either of the viruses exhibit competitive suppression in the vector and further evaluate transmission potential of these viruses in the mosquito salivary glands.

Group Figure
Immunofluorescent images showing tissue-specific infection of chikungunya virus in Aeses aegypti. Viral infection in the midgut, ovaries, and salivary glands

Recent publications

Kumar, R., Mehta, D., Mishra, N., Nayak, D., Sunil, S. 2021/ Role of host-mediated post-translational modifications (PTMs) in RNA virus pathogenesis. International J of Mol Sciences. Int J Mol Sci  22(1), 323 PubMed link

Shastri, J.S., Parikh, S., Agrawal, S., Chatterjee, N., Pathak, M., Chaudhary, S., Sharma, C., Kanakan, A., Vivekanand, A., Vasudevan, J.S., Maurya, R., Fatihi, S., Thukral, L., Agrawal, A., Pinto, L., Pandey, R., Sunil, S. 2020. Whole Genome Sequencing Confirmed SARS-CoV-2 Reinfections Among Healthcare Workers in India with Increased Severity in the Second Episode. SSRN-id3688220 

George, A., Amrutha, M.S., Srivastava, P., Sunil, S., Sai, V.V.R., Ramanathan, S. 2021/ Development of U-bent plastic optical fiber biosensor with plasmonic labels for detection of chikungunya non-structural protein 3. Analyst. PubMed link

Tripathi, P.K., Soni, A., Yadav, S.P.S., Kumar, A., Gaurav, N., Raghavendhar, S., Sharma, P., Sunil, S., Jayaram, A.B., Patel, A.K. 2020. Evaluation of novobiocin and telmisartan for anti-CHIKV activity. Virol DOI: 10.1016/j.virol.2020.05.010 PubMed link

Srivastava, P., Kumar, A., Hasan, A., Mehta, D., Kumar, R., Sharma, C., Sunil, S. 2020. Disease resolution in chikungunya-What decides the outcome? Front Immunol 11, 695 PubMed link

Rana, V.P., Popli, S., Saurav, G.K., Yadav, K., Kumar, A., Sunil, S., Kumar, N., Singh, O.P., Natarajan,K., Rajagopal, R. 2020. Aedes aegypti lachesin protein binds to the domain III of envelop protein of Dengue virus-2 and inhibits viral replication. Cell Microbiol doi: 10.1111/cmi.13200 PubMed link