Nitasha Kumar
A5059244401- HIV Research and Treatment
- Immune Cell Function and Interaction
- COVID-19 Clinical Research Studies
- T-cell and B-cell Immunology
- Cytomegalovirus and herpesvirus research
- Long-Term Effects of COVID-19
- HIV/AIDS drug development and treatment
- HIV/AIDS Research and Interventions
- Immune cells in cancer
- Tracheal and airway disorders
- SARS-CoV-2 and COVID-19 Research
- Peptidase Inhibition and Analysis
- Intensive Care Unit Cognitive Disorders
- Reproductive System and Pregnancy
- Congenital Diaphragmatic Hernia Studies
- Airway Management and Intubation Techniques
- Viral Infections and Immunology Research
- Radiopharmaceutical Chemistry and Applications
- HIV-related health complications and treatments
- Immune responses and vaccinations
- Animal Virus Infections Studies
- SARS-CoV-2 detection and testing
- Pneumocystis jirovecii pneumonia detection and treatment
- Sepsis Diagnosis and Treatment
- Tryptophan and brain disorders
University Hospital of Bern
2025
University of Bern
2025
University of California, San Francisco
2021-2024
University of California System
2023
San Francisco VA Health Care System
2021-2022
Peter Doherty Institute
2016-2020
The University of Melbourne
2015-2020
The Royal Melbourne Hospital
2017-2020
University College London Hospitals NHS Foundation Trust
2020
University College London
2020
The mechanisms of postacute medical conditions and unexplained symptoms after SARS-CoV-2 infection [Long Covid (LC)] are incompletely understood. There is growing evidence that viral persistence, immune dysregulation, T cell dysfunction may play major roles. We performed whole-body positron emission tomography imaging in a well-characterized cohort 24 participants at time points ranging from 27 to 910 days acute using the radiopharmaceutical agent [
Abstract The immunological features that distinguish COVID-19-associated acute respiratory distress syndrome (ARDS) from other causes of ARDS are incompletely understood. Here, we report the results comparative lower tract transcriptional profiling tracheal aspirate 52 critically ill patients with COVID-19 or etiologies, as well controls without ARDS. In contrast to a “cytokine storm,” observe reduced proinflammatory gene expression in when compared due causes. is characterized by...
Limited data are available on the long-term clinical and immunologic consequences of SARS-CoV-2 infection in people with HIV (PWH).We measured SARS-CoV-2-specific humoral cellular responses without recovering from COVID-19 ( n = 39 43, respectively) using binding antibody, surrogate virus neutralization, intracellular cytokine staining, inflammatory marker assays. We identified individuals experiencing postacute sequelae (PASC) evaluated parameters. used linear regression generalized models...
ABSTRACT The etiologic mechanisms of post-acute medical morbidities and unexplained symptoms (Long COVID) following SARS-CoV-2 infection are incompletely understood. There is growing evidence that viral persistence immune dysregulation may play a major role. We performed whole-body positron emission tomography (PET) imaging in cohort 24 participants at time points ranging from 27 to 910 days acute using novel radiopharmaceutical agent, [ 18 F]F-AraG, highly selective tracer allows for...
We recently described that HIV latent infection can be established in vitro following incubation of resting CD4+ T-cells with chemokines bind to CCR7. The main aim this study was fully define the post-integration blocks virus replication model CCL19-induced latency.High levels integrated DNA but low production reverse transcriptase (RT) found CCL19-treated infected either wild type (WT) NL4.3 or single round envelope deleted pseudotyped (NL4.3- Δenv). Supernatants from cells WT NL4.3- Δenv...
Latently infected resting CD4+ T cells are a major barrier to HIV cure. Understanding how latency is established, maintained and reversed critical identifying novel strategies eliminate latently cells. We demonstrate here that co-culture of syngeneic myeloid dendritic (mDC) can dramatically increase the frequency DNA integration latent infection in non-proliferating memory, but not naïve, Latency was eliminated when cell-to-cell contact prevented mDC-T cell co-cultures reduced clustering...
In people living with HIV on antiretroviral therapy, latency is the major barrier to a cure. persists preferentially in CD4+ T cells expressing multiple immune checkpoint (IC) molecules, including programmed death (PD)-1, cell Ig and mucin domain-containing protein 3 (TIM-3), lymphocyte associated gene (LAG-3), immunoreceptor ITIM domains (TIGIT). We aimed determine whether these other IC molecules have functional role maintaining blocking Abs reverses latency. Using an vitro model that...
HIV latency is the major barrier to a cure for people living with (PLWH) on antiretroviral therapy (ART) because virus persists in long-lived non-proliferating and proliferating latently infected CD4+ T cells. Latently cells do not express viral proteins are therefore visible immune mediated clearance. Therefore, identifying interventions that can reverse also enhance clearance of high interest. Interferons (IFNs) have multiple enhancing effects inhibit replication activated However, IFNs...
Abstract Dexamethasone is the standard of care for critically ill patients with COVID-19, but mechanisms by which it decreases mortality and its immunological effects in this setting are not understood. Here we perform bulk single-cell RNA sequencing samples from lower respiratory tract blood, assess plasma cytokine profiling to study dexamethasone on both systemic pulmonary immune cell compartments. In blood samples, associated decreased expression genes T activation, including TNFSFR4...
Combination antiretroviral therapy (cART) is able to control HIV-1 viral replication, however long-lived latent infection in resting memory CD4+ T-cells persist. The mechanisms for establishment and maintenance of remain unclear. Previously we have shown that co-cultured with CD11c+ myeloid dendritic cells (mDC) produced a population non-proliferating infection. Here asked whether different antigen presenting (APC), including subpopulations DC monocytes, were induce post-integration T-cells,...
A hallmark of coronavirus transcription is the generation negative-sense RNA intermediates that serve as templates for synthesis positive-sense genomic (gRNA) and an array subgenomic mRNAs (sgRNAs) encompassing sequences arising from discontinuous transcription. Existing PCR-based diagnostic assays SAR-CoV-2 are qualitative or semi-quantitative do not provide resolution needed to assess complex dynamics SARS-CoV-2 over course infection. We developed validated a novel panel sensitive,...
COVIDTrach is a UK multicentre prospective cohort study project that aims to evaluate the outcomes of tracheostomy in patients with COVID-19 receiving mechanical ventilation and record incidence SARS-CoV-2 infection among healthcare workers involved procedure.Data on patient demographic, clinical history were entered prospectively updated over time via an online database (REDCap). Clinical variables compared outcomes, logistic regression used develop model for mortality. Participants...
A major barrier to human immunodeficiency virus (HIV) eradication is the long-term persistence of latently infected CD4+ T cells harboring integrated replication-competent virus. It has been proposed that homeostatic proliferation these drives reservoir in absence reactivation, thus avoiding cell death due either virus-mediated cytopathicity or immune effector mechanisms. Here, we conducted an experimental depletion eight antiretroviral therapy (ART)-treated, simian (SIV)-infected rhesus...
Abstract HIV latency occurs predominantly in long-lived resting CD4+ T cells; however, latent infection also cell subsets, including proliferating cells. We compared the establishment and maintenance of nonproliferating human cells cocultured with syngeneic myeloid dendritic (mDC). Resting were labeled proliferation dye eFluor 670 cultured alone or mDC, plasmacytoid cells, monocytes presence staphylococcal enterotoxin B (SEB). Cells for 24 h infected CCR5-tropic enhanced GFP (EGFP) reporter...
ABSTRACT Background Limited data are available on the long-term clinical and immunologic consequences of SARS-CoV-2 infection in people with HIV (PWH). Methods We measured specific humoral cellular responses without recovering from COVID-19 (n=39 n=43, respectively) using binding antibody, surrogate virus neutralization, intracellular cytokine staining, inflammatory marker assays. identified individuals experiencing post-acute sequelae (PASC) evaluated parameters. used linear regression...
Developing robust in vitro models of HIV latency is needed to better understand how established, maintained and reversed. In this study, we examined the effects donor variability, titre co-receptor usage on establishing using two latency. Using CCL19 model latency, found that up 50% donors, enhanced latent infection resting CD4+ T-cells by CXCR4-tropic presence low dose IL-2. Increasing infectious increased both productive T-cells. a different where myeloid dendritic cells (mDC) were...
Abstract Purpose COVIDTrach is a UK multi-centre prospective cohort study project evaluating the outcomes of tracheostomy in patients with COVID-19 receiving mechanical ventilation. It also examines incidence SARS-CoV-2 infection among healthcare workers involved procedure. Method An invitation to participate was sent all NHS departments patients. Data entered prospectively and clinical updated via an online database (REDCap). Clinical variables were compared using multivariable regression...
People with HIV (PWH) are at greater risk of developing lung diseases even when they antiretroviral therapy (ART)-adherent and virally suppressed. The most common pulmonary function abnormality in PWH is that impaired diffusing capacity the lungs for carbon monoxide (DL CO ), which an independent factor increased mortality PWH. Earlier work has identified several plasma biomarkers inflammation immune activation to be associated decreased DL . However, underpinning molecular mechanisms...
Secondary bacterial pneumonia (2°BP) is associated with significant morbidity following respiratory viral infection, yet remains incompletely understood. In a prospective cohort of 112 critically ill adults intubated for COVID-19, we comparatively assess longitudinal airway microbiome dynamics and the pulmonary transcriptome patients who developed 2°BP versus controls did not. We find that significantly both mortality corticosteroid treatment. The in characterized by increased RNA mass...
Although there have been great advancements in the field of HIV treatment and prevention, is no cure. There are two types HIV: HIV-1 HIV-2. In addition to genetic differences between HIV, HIV-2 infection causes a slower disease progression, rate new infections has dramatically decreased since 2003. Like HIV-1, capable establishing latent CD4 + T cells, thereby allowing virus evade viral cytopathic effects detection by immune system. The mechanisms underlying latency not fully understood,...