Disease Biology Laboratory
Major Focus:
Investigating Signaling Pathways of Thrombosis, Inflammation, and Innate and Adaptive Immune Responses in Human Health and Diseases, and Identifying Biomarkers and Molecular Targets to Develop Potential Therapeutics.
SARS-CoV-2 infection: ARDS and pulmonary fibrosis and host immune response
Molecular signaling of inflammation, thrombosis and thrombophilia, promoting lung injury and cell death, leading to clinical conditions like acute respiratory distress syndrome (ARDS) and hypoxemia, and developing pulmonary fibrosis in SARS- CoV-2 infected animals and patients: Role of Akt, p38 and HIF1α, and epithelial to mesenchymal transition (EMT) signaling.
Interferon and antibody responses in SARS-CoV-2 infection in mice and patients
Testing anti-inflammatory/thrombotic drugs in SARS-CoV-2 infected animals.
Cytokine signaling in platelet activation in SARS-CoV-2 infection.
Related pub: Agarwal S et al. 2022. Clinical Translation Medicine; Shrimali NM et al. 2021 EBioMedicine.
Dengue virus (DENV) and Japanese encephalitis virus (JEV) infection: pathogenesis and host immune response
Investigating the pro-viral role of platelet factor 4 (PF4 or CXCL4) in the pathogenesis of DENV and JEV infection using PF4-/- mice.
Investigating the autophagy and interferon synthesis pathways in DENV and JEV infection.
Developing small molecule inhibitors against PF4:CXCR3(receptor of PF4) pathway and testing their antiviral efficacy in DENV and JEV mice models.
Related pub: Singh A et al. 2023 Journal of Thrombosis and Haemostasis; Singh A et al. 2023 Cytokine; Ojha et al. 2019 EBioMedicine.
DENV: heterotypic infection and host immune response
Investigating interferon and antibody responses in in heterotypic DENV infection in mice and patients.
Antibody-dependent enhancement (ADE) and disease severity in mice and patients with primary and secondary infections with DENV subtypes: Role of IgG/complement factors with FcγR.
Viral infections in diabetes: severity and host immune response
Severity of SARS-CoV-2 infection and host immune response in mice with type 1 diabetes (T1D)/ type 2 diabetes (T2D).
Severity of DENV infection and host immune response in mice with T1D/T2D.
Diabetes: pathogenesis of inflammation, thrombosis and pulmonary fibrosis
Hyperglycemia induced thrombosis, thrombophilia and inflammation in mice and patients with T1D/T2D.
Pulmonary fibrosis in mice with T1D/T2D: EMT signaling.
Platelet and immune cells interactions contribute to thrombo-inflammatory complications in mice and patients with T2D.
Hyperglycemia induced glycosylation of CD36 in platelets promotes oxLDL-mediated platelet hyperactivation and thrombosis in T2D patients: Lyn-JNK signaling.
Related pub: Agarwal S et al. 2023 FEBS Journal; Agarwal S et al. 2023 Clinical Experimental Immunology.
Genetic polymorphism and high altitude adaptation in Tibetan highlanders
Tibetan highlanders carrying PHD2D4E;C127S polymorphisms are protected from polycythemia and inflammation, on the other hand, non-Tibetan travelers from sea level to high altitudes are predisposed to mountain maladies like pulmonary and cerebral edema: Role of PHD2, HIF1α and Akt signaling.
Tibetans carrying PHD2D4E;C127S polymorphisms are protected from hypoxia induced thrombosis and thrombophilia? Role of PHD2, HIF1α and Akt signaling.
Tibetans carrying PHD2D4E;C127S polymorphisms are protected from viral infections at high altitude under hypoxia? Role of PHD2, HIF1α and Akt signaling.
Related pub: Bhattacharya S et al. 2021 EBioMedicine; Sharimali NM et al. 2021 EBioMedicine.
Diabetes in highlander population
Metabolome profiles of glucose and fatty acid oxidation pathways in plasma/blood cells in T2D patients from high altitudes are different sea level counterparts? Does high-altitude hypoxia and PHD2, HIF1α signaling play role? Does gut microbiome play role? Do hypoxia-responsive factors crosstalk with metabolic enzymes to alter metabolome profiles of T2D patients at high altitude? Genetic polymorphism and/or epigenetic modifications of metabolic enzymes play role?
Hemolytic disorders: pathogenesis of inflammation and thrombosis
Platelet-immune cells crosstalk in the pathogenesis of systemic inflammation in hemolytic disorders including paroxysmal nocturnal hemoglobinuria (PNH) and sickle cell disease (SCD): Role of extracellular hemoglogin (Hb).
Related pub: Sighal R et al. 2015 Haematologica; Sighal R et al. 2016 Clinical Immunology; Sighal R et al. 2018 Euro J Immunology; Sighal R et al. 2019 Journal Immunology Research; Bhasym A et al. 2019 Clinical Experimental Immunology.
Autoimmune disorders: pathogenesis of inflammation and thrombophilia
Systemic inflammation in autoimmune disorders like atypical hemolytic uremic syndrome (aHUS) and systemic lupus erythematosus (SLE): Role of complement factors H polymorphisms.
Thrombophilia or hypercoagulation in aHUS and SLE: Crosstalk between complement and coagulation factors.
Related pub: Bhasym A et al. 2019 Journal of Clinical Immunology