A5038384623- Immune responses and vaccinations
- COVID-19 Clinical Research Studies
- Malaria Research and Control
- SARS-CoV-2 and COVID-19 Research
- Mosquito-borne diseases and control
- COVID-19 epidemiological studies
- Vaccine Coverage and Hesitancy
- Immune Cell Function and Interaction
- Complement system in diseases
- Viral gastroenteritis research and epidemiology
- Bacterial biofilms and quorum sensing
- Medical and Biological Ozone Research
- COVID-19 Impact on Reproduction
- Ultrasound and Hyperthermia Applications
- Transgenic Plants and Applications
- Drug Transport and Resistance Mechanisms
- Liver Disease and Transplantation
- Enzyme Structure and Function
- Amino Acid Enzymes and Metabolism
- Parasites and Host Interactions
- Enzyme Production and Characterization
- Immune cells in cancer
- HIV Research and Treatment
- Forest Biomass Utilization and Management
- Genomics and Phylogenetic Studies
University of Washington
2020-2023
Indian Institute of Science Bangalore
2022-2023
St.John's Medical College Hospital
2023
St. John's University
2022
Rutgers, The State University of New Jersey
2016-2017
Whole-sporozoite vaccines engender sterilizing immunity against malaria in animal models and importantly, humans. Gene editing allows for the removal of specific parasite genes, enabling generation genetically attenuated (GAP) strains vaccination. Using rodent parasites, we have previously shown that late liver stage-arresting replication-competent (LARC) GAPs confer superior protection when compared with early replication-deficient radiation-attenuated sporozoites. However, generating a...
The human malaria parasite Plasmodium vivax remains vastly understudied, mainly due to the lack of suitable laboratory models. Here, we report a humanized mouse model test interventions that block P. transition from liver stage infection blood infection. Human liver-chimeric FRGN huHep mice infected with sporozoites were infused reticulocytes, allowing exo-erythrocytic merozoites reticulocyte and development into all erythrocytic forms, including gametocytes, in vivo. In order utility this...
This proof-of-concept study tested if prior BCG revaccination can qualitatively and quantitively enhance antibody T-cell responses induced by Oxford/AstraZeneca ChAdOx1nCoV-19 or COVISHIELD™, an efficacious the most widely distributed vaccine in India. We compared COVISHIELD™ longitudinal immune 21 re-vaccinees (BCG-RV) 13 BCG-non-revaccinees (BCG-NRV), all of whom were vaccinated at birth; latent tuberculosis negative SARS-CoV-2 seronegative to vaccination. Compared BCG-NRV, BCG-RV...
There are limited global data on head-to-head comparisons of vaccine platforms assessing both humoral and cellular immune responses, stratified by pre-vaccination serostatus. The COVID-19 vaccination drive for the Indian population in age group 18–45 years began April 2021 when seropositivity rates general were rising due to delta wave pandemic during April–May 2021. Between June 30, 2021, Jan 28, 2022, we enrolled 691 participants across four clinical sites India. In this non-randomised...
During the coronavirus disease 2019 (COVID-19) pandemic, large differences in susceptibility and mortality due to severe acute respiratory syndrome 2 (SARS-CoV-2) infection have been reported between populations Europe South Asia. While both host environmental factors (including Mycobacterium bovis BCG vaccination) proposed explain this, potential biological substrate of these is unknown. We purified peripheral blood mononuclear cells from individuals living India Netherlands at baseline 10...
This study characterized mechanisms of Bacille Calmette-Guérin (BCG) revaccination-induced trained immunity (TI) in India. Adults, BCG vaccinated at birth, were sampled longitudinally before and after a second dose. revaccination significantly elevated tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β, IL-6 HLA-DR+CD16-CD14hi monocytes, demonstrating induction TI. Mycobacteria-specific CD4+ T cell interferon (IFN) γ, IL-2, TNF-α higher re-vaccinees correlated positively with TI...
Abstract Detailed characterisation of immune responses induced by COVID-19 vaccines rolled out in India: COVISHIELD TM (CS) and COVAXIN® (CO) a pre-exposed population is only recently being discovered. We addressed this issue subjects who received their primary series vaccination between November 2021 January 2022. Both are capable strongly boosting Wuhan Spike-specific neutralising antibody, polyfunctional Th1 cytokine producing CD4+ T-cells single IFN-γ + CD8+ T-cells. Consistent with...
Antibodies against the Plasmodium falciparum circumsporozoite protein (PfCSP) can block hepatocyte infection by sporozoites and protect malaria. Needle-free vaccination strategies are desirable, yet most PfCSP-targeted vaccines like RTS,S require needle-based administration. Here, we evaluated edible algae, Arthrospira platensis (commonly called 'spirulina') as a malaria vaccine platform. Spirulina were genetically engineered to express virus-like particles (VLPs) consisting of woodchuck...
Abstract This study tested if prior BCG revaccination can further boost immune responses subsequently induced by an otherwise efficacious Oxford/AstraZeneca ChAdOx1nCoV-19 vaccine, referred to as COVISHIELDTM in India. We compared longitudinal 21 re-vaccinees (BCG-RV) and 13 BCG-non-revaccinees (BCG-NRV), all of whom were vaccinated at birth latent tuberculosis negative, after prime with baseline samples that collected pre-pandemic pre-BCG revaccination. Compared BCG-NRV, BCG-RV displayed...
Aggregatibacter actinomycetemcomitans, a Gram-negative bacterium, is the causative agent of localized aggressive periodontitis. Attachment to biotic surface critical first step in A. actinomycetemcomitans infection process for which exopolysaccharides have been shown be essential. In addition, pga operon, containing genes encoding biosynthetic proteins poly-N-acetyl glucosamine (PNAG), plays key role virulence, as mutant strain lacking operon induces significantly less bone resorption. Among...
Surgical instrumentation is now available to facilitate wound debridement. The 2 primary options involve different energy applications, but both have the potential spray. Versajet II (Smith & Nephew, London, UK) utilizes a high-powered water jet disrupt tissue and remove debris by means of Venturi effect. SonicVac (Misonix, Farmingdale, NY) direct-contact, low-frequency ultrasound debriding device. It delivers high-energy surface via fluid medium, causing bubble cavitation, physical effect...
The oral pathogen Aggregatibacter actinomycetemcomitans uses pga gene locus for the production of an exopolysaccharide made up a linear homopolymer β-1,6-N-acetyl-d-glucosamine (PGA). An enzyme encoded by pgaB operon in A. is de-N-acetylase, which used to alter PGA. full length (AaPgaB) and N-terminal catalytic domain (residues 25-290, AaPgaBN) from were cloned, expressed purified. enzymatic activities AaPgaB enzymes determined using 7-acetoxycoumarin-3-carboxylic acid as substrate....
Plasmodium sporozoites invade hepatocytes and transform into liver stages within a parasitophorous vacuole (PV). The parasites then grow replicate their genome to form exoerythrocytic merozoites that infect red blood cells. We report the human malaria parasite falciparum (Pf) expresses C-type ATP-binding cassette transporter, Pf ABCC2, which marks transition from invasive sporozoite intrahepatocytic early stage. Using humanized mouse infection model, we show ABCC2 localizes plasma membrane...
Abstract Background There are limited global data on head-to-head comparisons of vaccine platforms assessing both humoral and cellular immune responses, stratified by pre-vaccination serostatus. The COVID-19 vaccination drive for the Indian population in 18 to 45-year age-group began April 2021 when seropositivity rates general were rising due Delta wave April-May 2021. Methods Between 30 June 28 January 2022, we enrolled 691 participants 18-45 age group across 4 clinical sites India. In...
This study aimed to characterize mechanisms of BCG revaccination induced trained immunity (TI) in a TB endemic country, India. Adults, vaccinated at birth, were sampled longitudinally post second dose pre-COVID-19. Whole blood and PBMC stimulation with mycobacterial heterologous stimuli followed by flow-cytometric analysis, measurement secreted mediators RNA-seq approaches used characterise TI. significantly elevated TNFα, IL-1β IL-6 HLA-DR+CD16-CD14hi monocytes, demonstrating induction...
Liver stage (LS) Plasmodia mature in 2-2.5 days rodents compared to 5-6 humans. Plasmodium-specific CD8+ T cell expansion differs across these varied timespans. To mimic the kinetics of cells human Plasmodium infection, a two-dose challenge mouse model that achieved 4-5 LS exposure was developed. In this model, mice were inoculated with non-protective, low dose late-arresting, genetically-attenuated sporozoites initiate activation and then re-inoculated 2-3 later wild-type sporozoites....
Purpose: Implant infections are highly morbid and costly. Staph species the primary agents. Despite extensive efforts, satisfactory treatment is elusive, largely due to persistence of biofilm. Ultrasound a known biofilm disrupter. A new low frequency direct contact ultrasound (LFDCU) device available for wound debridement. This study meant determine if energy levels in this instrument effective dispersing Methods:Staph. epidermidis was grown on one centimeter diameter metallic discs both...
Abstract During the COVID-19 pandemic, large differences in susceptibility and mortality due to SARS-CoV-2 infection have been reported between populations Europe South Asia. While both host environmental factors (including BCG vaccination) proposed explain this, potential biological substrate of these is unknown. We purified peripheral blood mononuclear cells from individuals living India Netherlands at baseline 10-12 weeks after vaccination. compared chromatin accessibility two baseline,...