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Awasthi, A.

Publications and source records attributed to Awasthi, A..

4 recordsLinked to original sources

Immunological and cardio-vascular pathologies associated with SARS-CoV-2 infection in golden syrian hamster

Severe acute respiratory syndrome coronavirus (SARS-CoV)-2 infection in golden Syrian hamster (GSH) causes lung pathology and resembles human coronavirus disease (Covid-19). However, extra-pulmonary pathologies of SARS-CoV-2 infection that result in long Covid remains undefined in GSH. Here, using in silico modelling we show that hamster angiotensin-converting enzyme-2 (ACE-2) and neuropilin-1 (NRP-1) interaction with SARS-CoV-2 is similar to human. Intranasal SARS-CoV-2 infection in GSH resulted in early onset of lung pathologies marked by aggressive inflammatory response. Remarkably, late phase of SARS-CoV2 infection in GSH showed cardiovascular complications (CVC) characterized by ventricular hypertrophy, ventricular wall thickening, interstitial coronary fibrosis and altered lipidomics with elevated cholesterol, low-density lipoprotein and long chain fatty acid triglycerides. Moreover, serum metabolomics profile of infected GSH correlated with Covid19 patients. Together, we propose GSH as a suitable animal model to study immediate and long Covid19 pathologies that could be extended to therapeutics against Covid19 related CVC.

microbiology

Evaluation of Safety and Immunogenicity of an Adjuvanted, TH-1 Skewed, Whole Virion Inactivated SARS-CoV-2 Vaccine - BBV152

We report the development and evaluation of safety and immunogenicity of a whole virion inactivated SARS-COV-2 vaccine (BBV152), adjuvanted with aluminium hydroxide gel (Algel), or a novel TLR7/8 agonist adsorbed Algel. We used a well-characterized SARS-CoV-2 strain and an established vero cell platform to produce large-scale GMP grade highly purified inactivated antigen, BBV152. Product development and manufacturing were carried out in a BSL-3 facility. Immunogenicity was determined at two antigen concentrations (3g and 6g), with two different adjuvants, in mice, rats, and rabbits. Our results show that BBV152 vaccine formulations generated significantly high antigen-binding and neutralizing antibody titers, at both concentrations, in all three species with excellent safety profiles. The inactivated vaccine formulation containing TLR7/8 agonist adjuvant-induced Th1 biased antibody responses with elevated IgG2a/IgG1 ratio and increased levels of SARS-CoV-2 specific IFN-{gamma}+ CD4 T lymphocyte response. Our results support further development for Phase I/II clinical trials in humans.

immunology

Tracking mitochondrial density and positioning along a growing neuronal process in individual C. elegans neuron using a long-term growth and imaging microfluidic device

The long cellular architecture of neurons requires regulation in part through transport and anchoring events to distribute intracellular organelles. During development, cellular and sub-cellular events such as organelle additions and their recruitment at specific sites on the growing axons occur over different time scales and often show inter-animal variability thus making it difficult to identify specific phenomena in population averages. To measure the variability in sub-cellular events such as organelle positions, we developed a microfluidic device to feed and immobilize C. elegans for high-resolution imaging over several days. The microfluidic device enabled long-term imaging of individual animals and allowed us to investigate organelle density using mitochondria as a testbed in a growing neuronal process in vivo. Sub-cellular imaging of an individual neuron in multiple animals, over 36 hours in our microfluidic device, shows the addition of new mitochondria along the neuronal process and an increase in the accumulation of synaptic vesicles at synapses, both organelles with important roles in neurons. Long-term imaging of individual C. elegans touch receptor neurons identifies addition of new mitochondria and interacts with other moving mitochondria only through fission and fusion events. The addition of new mitochondria takes place along the entire neuronal process length and the threshold for the addition of a new mitochondrion is when the average separation between the two pre-existing mitochondria exceeds 24 micrometers.

neuroscience

Regulated distribution of mitochondria in touch receptor neurons of C. elegans influences touch response

Density of mitochondria and their localization at specific sub-cellular regions of the neurons is regulated by molecular motors, their adaptors and the cytoskeleton. However, the regulation of the mitochondrial density, the positioning of mitochondria along the neuronal process and the role of axonal mitochondria in neuronal function remain poorly understood. This study shows that the density of mitochondria in C. elegans touch receptor neuron processes remains constant through development. Simulations show that mitochondrial positioning along parts of the neuronal process that are devoid of synapses is regulated. Additionally, we also demonstrate that axonal mitochondria are necessary for maintaining touch responsiveness.

neuroscience