Publications by authors named "Pritha Sen"

Article Synopsis
  • Immune checkpoint inhibitors, a type of cancer treatment, can cause serious side effects, including immune-related myocarditis (irMyocarditis), which can be fatal.
  • Researchers studied immune responses in the heart, tumor, and blood of 28 patients with irMyocarditis using advanced techniques like single-cell RNA sequencing and T-cell receptor (TCR) sequencing.
  • Their findings showed an increase in certain immune cells in the heart tissue of irMyocarditis patients and identified specific TCR clones associated with severe cases, shedding light on the disease's biology and potential biomarkers.
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  • - Pregnancy may worsen the severity of SARS-CoV-2 and other respiratory infections, but the reasons behind this increased risk are not well understood.
  • - A study involving 226 women, including 152 pregnant and 74 non-pregnant, showed that pregnant women experience significant changes in T cell responses and immune functions after SARS-CoV-2 infection.
  • - The study found increased levels of interleukin-27 in pregnant women, which is linked to T cell exhaustion, suggesting that unique immune responses during pregnancy could make them more vulnerable to viral infections.
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  • - Respiratory fungal infections pose a serious health risk and existing animal models don't accurately mimic human disease, prompting the need for better research models.
  • - This study used primary human airway epithelial cells (hAECs) to examine responses to two important fungal pathogens through single-cell RNA sequencing.
  • - Findings showed that while both fungi caused cellular stress and inflammation, they impacted different cell types and pathways, highlighting unique stress responses that could lead to potential treatment targets.
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  • Immune checkpoint inhibitor (ICI) therapy has significantly advanced cancer treatment but is often complicated by immune-related adverse events like checkpoint inhibitor colitis (irColitis).
  • A study profiling around 300,000 cells from patients with irColitis uncovered key immune cell expansions and molecular changes in the colon mucosa and blood, highlighting the complexity of the condition.
  • Findings indicate that specific T cells and epithelial interactions are crucial for understanding irColitis and may lead to new therapeutic approaches for managing this side effect of ICI therapy.
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Pregnancy is a risk factor for increased severity of SARS-CoV-2 and other respiratory infections. The mechanisms underlying this risk have not been well-established, partly due to a limited understanding of how pregnancy shapes immune responses. To gain insight into the role of pregnancy in modulating immune responses at steady state and upon perturbation, we collected peripheral blood mononuclear cells (PBMC), plasma, and stool from 226 women, including 152 pregnant individuals (n = 96 with SARS-CoV-2 infection and n = 56 healthy controls) and 74 non-pregnant women (n = 55 with SARS-CoV-2 and n = 19 healthy controls).

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Article Synopsis
  • Immune checkpoint inhibitors (ICIs) can lead to serious immune-related adverse events (irAEs), with ICI-related myocarditis (irMyocarditis) being particularly dangerous and the most lethal among these events.
  • Researchers explored immune responses in the heart, tumors, and blood of 28 patients with irMyocarditis compared to 23 controls, using advanced techniques like single-cell RNA sequencing and proteomics.
  • Key findings revealed a unique presence of specific immune cells in irMyocarditis heart tissue, distinct T cell responses in heart vs. tumor, and identified novel biomarkers related to fatality that could inform future therapies.
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Prohibitin is a multifunctional protein that plays an important role in numerous cellular processes. Membrane-associated mitochondrial prohibitin complex is made up of two subunits, PHB1 and PHB2 which are ubiquitously expressed and analogous to each other. High levels of prohibitin expression have consequently been found in esophageal cancer, endometrial adenocarcinoma, gastric cancer, hepatocellular carcinoma, breast cancer and bladder cancer.

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The field of infectious diseases currently takes a reactive approach and treats infections as they present in patients. Although certain populations are known to be at greater risk of developing infection (eg, immunocompromised), we lack a systems approach to define the true risk of future infection for a patient. Guided by impressive gains in "omics" technologies, future strategies to infectious diseases should take a precision approach to infection through identification of patients at intermediate and high-risk of infection and deploy targeted preventative measures (ie, prophylaxis).

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Objective: Little is known about CSF profiles in patients with acute COVID-19 infection and neurological symptoms. Here, CSF was tested for SARS-CoV-2 RNA and inflammatory cytokines and chemokines and compared to controls and patients with known neurotropic pathogens.

Methods: CSF from twenty-seven consecutive patients with COVID-19 and neurological symptoms was assayed for SARS-CoV-2 RNA using quantitative reverse transcription PCR (RT-qPCR) and unbiased metagenomic sequencing.

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Immunomodulating therapies for COVID-19 may carry risks of reactivating latent infections in foreign-born people. We conducted a rapid review of infection-related complications of immunomodulatory therapies for COVID-19. We convened a committee of specialists to formulate a screening and management strategy for latent infections in our setting.

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  • This study examines the pathophysiology of COVID-19 by analyzing single-cell and spatial atlases from various organ autopsy samples of individuals who died from the virus.
  • Findings revealed significant changes in lung tissue, including impaired tissue regeneration and inflammation, indicating how SARS-CoV-2 affects different cell types.
  • The research provides crucial insights into the biological impact of severe COVID-19, aiding in the development of potential new treatments.
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  • The SARS-CoV-2 pandemic has led to over 1 million deaths worldwide, primarily due to severe lung injuries and multiple organ failures, but there is limited understanding of the immune responses involved in COVID-19.
  • Researchers collected and analyzed over 420 tissue samples from various organs of 17 COVID-19 victims, utilizing advanced techniques like RNA sequencing to map out cellular changes related to their illness.
  • Significant findings include alterations in lung tissue cell types, such as the increase of specific progenitor cells and myofibroblasts, indicating impaired tissue repair and failed regenerative processes in severely damaged lungs.
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We evaluated the incidence, distribution, and histopathologic correlates of microvascular brain lesions in patients with severe COVID-19. Sixteen consecutive patients admitted to the intensive care unit with severe COVID-19 undergoing brain MRI for evaluation of coma or neurologic deficits were retrospectively identified. Eleven patients had punctate susceptibility-weighted imaging (SWI) lesions in the subcortical and deep white matter, eight patients had >10 SWI lesions, and four patients had lesions involving the corpus callosum.

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In severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, viral load peaks early and declines quickly after symptom onset. Severe coronavirus disease 2019 (COVID-19) is marked by aberrant innate and adaptive immune responses with an abnormal cytokine profile and multiorgan system dysfunction that persists well after viral clearance. A purely antiviral treatment strategy may therefore be insufficient, and antiviral agents have not shown a benefit later in the illness course.

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Background: The efficacy of interleukin-6 receptor blockade in hospitalized patients with coronavirus disease 2019 (Covid-19) who are not receiving mechanical ventilation is unclear.

Methods: We performed a randomized, double-blind, placebo-controlled trial involving patients with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, hyperinflammatory states, and at least two of the following signs: fever (body temperature >38°C), pulmonary infiltrates, or the need for supplemental oxygen in order to maintain an oxygen saturation greater than 92%. Patients were randomly assigned in a 2:1 ratio to receive standard care plus a single dose of either tocilizumab (8 mg per kilogram of body weight) or placebo.

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Background: Remdesivir is efficacious for severe coronavirus disease 2019 (COVID-19) in adults, but data in pregnant women are limited. We describe outcomes in the first 86 pregnant women with severe COVID-19 who were treated with remdesivir.

Methods: The reported data span 21 March to 16 June 2020 for hospitalized pregnant women with polymerase chain reaction-confirmed severe acute respiratory syndrome coronavirus 2 infection and room air oxygen saturation ≤94% whose clinicians requested remdesivir through the compassionate use program.

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Importance: Microvascular lesions are common in patients with severe COVID-19. Radiologic-pathologic correlation in one case suggests a combination of microvascular hemorrhagic and ischemic lesions that may reflect an underlying hypoxic mechanism of injury, which requires validation in larger studies.

Objective: To determine the incidence, distribution, and clinical and histopathologic correlates of microvascular lesions in patients with severe COVID-19.

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Cytomegalovirus (CMV) is an important cause of morbidity and mortality in the immunocompromised host. In transplant recipients, a variety of clinically important "indirect effects" are attributed to immune modulation by CMV, including increased mortality from fungal disease, allograft dysfunction and rejection in solid organ transplantation, and graft-versus-host-disease in stem cell transplantation. Monocytes, key cellular targets of CMV, are permissive to primary, latent and reactivated CMV infection.

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Background: Glioblastomas are the most common and lethal primary brain tumors. Microglia, the resident immune cells of the brain, survey their environment and respond to pathogens, toxins, and tumors. Glioblastoma cells communicate with microglia, in part by releasing extracellular vesicles (EVs).

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Iron porphyrins are potential catalysts for the electrocatalytic and photocatalytic reduction of CO2. It has been recently established that the reduction of CO2 by an iron porphyrin complex with a hydrogen bonding distal pocket involves at least two intermediates: a Fe(ii)-CO22- and a Fe(ii)-COOH species. A distal hydrogen bonding interaction was found to be key in determining the stability of these intermediates and affecting both the selectivity and rate of CO2 reduction.

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The neuroimmune system is involved in development, normal functioning, aging, and injury of the central nervous system. Microglia, first described a century ago, are the main neuroimmune cells and have three essential functions: a sentinel function involved in constant sensing of changes in their environment, a housekeeping function that promotes neuronal well-being and normal operation, and a defense function necessary for responding to such changes and providing neuroprotection. Microglia use a defined armamentarium of genes to perform these tasks.

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Iron porphyrin complexes with second-sphere distal triazole residues show a hydrogen evolution reaction (HER) catalyzed by the Fe(I) state in both organic and aqueous media, whereas an analogous iron porphyrin complex without the distal residues catalyzes the HER in the formal Fe(0) state. This activation of the Fe(I) state by the second-sphere residues lowers the overpotential of the HER by these iron porphyrin complexes by 50%. Experimental data and theoretical calculations indicate that the distal triazole residues, once protonated, enhance the proton affinity of the iron center via formation of a dihydrogen bond with an Fe(III)-H intermediate.

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The reduction of CO2 by an iron porphyrin complex with a hydrogen bonding distal pocket involves at least two intermediates. The resonance Raman data of intermediate I, which could only be stabilized at -95 °C, indicates that it is a Fe(II)-CO2(2-) adduct and is followed by an another intermediate II at -80 °C where the bound CO2 in intermediate I is protonated to form a Fe(II)-COOH species. While the initial protonation can be achieved using weak proton sources like MeOH and PhOH, the facile heterolytic cleavage of the C-OH bond in intermediate II requires strong acids.

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An ideal human immunodeficiency virus type 1 (HIV-1) vaccine would elicit potent cellular and humoral immune responses that recognize diverse strains of the virus. In the present study, combined methodologies (flow cytometry, Vbeta repertoire analysis, and complementarity-determining region 3 sequencing) were used to determine the clonality of CD8(+) T lymphocytes taking part in the recognition of variant epitope peptides elicited in Mamu-A*01-positive rhesus monkeys immunized with vaccines encoding diverse HIV-1 envelopes (Envs). Monkeys immunized with clade B Envs generated CD8(+) T lymphocytes that cross-recognized both clade B- and clade C-p41A epitope peptides using a large degree of diversity in Vbeta gene usage.

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To afford the greatest possible immune protection, candidate human immunodeficiency virus (HIV) vaccines must generate diverse and long-lasting CD8(+) T lymphocyte responses. In the present study, we evaluate T-cell receptor Vbeta (variable region beta) gene usage and a CDR3 (complementarity-determining region 3) sequence to assess the clonality of epitope-specific CD8(+) T lymphocytes generated in rhesus monkeys following vaccination and simian-human immunodeficiency virus (SHIV) challenge. We found that vaccine-elicited epitope-specific CD8(+) T lymphocytes have a clonal diversity comparable to those cells generated in response to SHIV infection.

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