Biology subjects

Jha, D.

Publications and source records attributed to Jha, D..

12 recordsLinked to original sources

bioRxiv2026

Genetic and structural interpretation of NLRP1 FIIND domain variants in glioma in an Indian cohort: a pilot study

Gliomas, particularly glioblastoma (GBM), are aggressive primary brain tumors associated with dysregulated NLR signaling, a pathway central to innate immunity and inflammation. NLRP1 triggers proinflammatory cytokine release and pyroptotic cell death via autoproteolytic cleavage. The FIIND missense variant rs11651270 (M1184V) may modulate this cleavage process. While NLRP1 polymorphisms are associated with various diseases and cancers, their specific impact on glioma remains to be investigated. In our study, five FIIND-domain single-nucleotide polymorphisms (SNPs) of NLRP1 rs371579423, rs58604457, rs57636751, rs11651270, and rs2301583, were investigated by Sanger sequencing in a clinical cohort of glioma patients and compared against population-matched controls from the GenomeIndia dataset (Rajasthan cohort) using genetic association models. Molecular dynamics simulations were performed to evaluate the structural effects of the missense variant rs11651270 (M1184V) in NLRP1 during pre- and post-cleavage states. The linked variants rs58604457 (G>A) and rs57636751 (C>T) exhibited complete linkage disequilibrium (r2=1.00) and were significantly associated with lower odds of glioma (odds ratio ~0.5). The missense variant rs11651270 (T>C) showed no association with glioma risk. Notably, the SNP rs2301583 had a higher allelic frequency in glioma cases despite being absent in the GenomeIndia population-based control catalogue. Molecular dynamics simulations revealed that the M1184V substitution stabilizes local FIIND architecture by preserving {beta}-strand organization through persistent interactions with neighboring residues. This study provides the first combined genetic and structural analysis of NLRP1 FIIND-domain variants in an Indian glioma cohort. These findings illustrate the potential value of integrating population-based genetic association with structural modelling to generate hypotheses and uncover potential functional mechanisms of inflammasome-gene variants in neuro-oncology.

cancer biology↗

bioRxiv2025

NLRP3 Inflammasome Exhibits Context-Dependent Roles in Glioblastoma-Astrocyte Crosstalk

Glioblastoma (GBM) is a highly aggressive brain tumor characterized by molecular and cellular heterogeneity and poor patient survival. NLRP3 inflammasome regulates inflammation and cell death with context-specific roles in cancer, but its functions in GBM tumour and astrocyte interactions remain unclear. In this study, we analyzed NLRP3 expression and function in GBM cell lines (LN-229 and LN18), astrocytes (SVG), patient-derived tissues, and organoids. Basal NLRP3 expression was higher in astrocytes than in GBM cells and increased after LPS stimulation, altering astrocyte morphology and NLRP3 subcellular localization. siRNA-mediated silencing of NLRP3 reduced GBM proliferation, migration, and viability in GBM cells, while enhancing proliferation and cytokine secretion in astrocytes, highlighting its context-dependent effects. NLRP3 deficiency exhibited reciprocal cytokine paracrine signaling, with GBM cells releasing elevated levels of IL-6 and TNF-, and astrocytes releasing elevated levels of IL-1{beta}. Glyburide treatment reduced NLRP3 expression and IL-1{beta} release in GBM cells but elevated NLRP3 and IL-1{beta} in astrocytes. Overall, these data reveal NLRP3s dual roles in GBM-astrocyte crosstalk, suggesting cell-type-selective inhibition for therapeutic exploration.

cancer biology↗

bioRxiv2025

NLRP12-mediated Glioblastoma-Astrocyte Cross-talk Promotes Tumor Growth

Nucleotide-binding domain leucine-rich repeat-containing receptors (NLR) are cytosolic pattern recognition receptors that regulate inflammation by sensing pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). NLRP12 is a cytosolic protein with inflammation-promoting and inflammation-attenuating properties. NLRP12 exhibits tumor-suppressive or tumor-promoting effects that may be cancer, cell-type, context-dependent, aided by differences in the microenvironment contributing to the pathophysiology of hepatocellular carcinoma, prostate cancer, colitis-associated cancer, and glioblastoma (GBM). GBM is a grade IV malignant brain tumor with poor patient survival and high tumor recurrence due to a heterogeneous cell population and angiogenesis. Our previous research reported NLRP12 as a potential prognostic marker for GBM with high expression in GBM patient tissues. In the present study, we investigated the role of NLRP12-mediated signalling between GBM and tumor-adjacent astrocytes, using a comprehensive panel of experimental models, including LN-229 GBM and SVG astrocyte cell lines, cell line-derived spheroids, patient-derived primary glioma cells, and patient-derived glioma organoids. We report that NLRP12 deficiency reduces cell proliferation and viability in the LN-229 cells, but increases these parameters in SVG cells. Furthermore, NLRP12-deficient LN-229 cells display attenuated ability to form three-dimensional spheroids, indicating a role of NLRP12 in anchorage-independent growth, which is considered a hallmark of tumorigenicity. Analysis of patient-derived glioma tissue and patient-derived GBM organoids revealed differential expression of NLRP12. Our findings suggest that NLRP12 modulates GBM cell proliferation, viability, and anchorage-independent growth in a cell-context dependent manner. The cell-type-specific roles of NLRP12 may underlie its complex contribution to GBM pathophysiology with implications for therapy and prognosis. SummaryNLRP12, a cytosolic regulator of inflammation, exhibits context-dependent roles in cancer. Its deficiency reduces glioblastoma cell proliferation, viability, and spheroid formation, while enhancing these properties in astrocytes, indicating a cell-type-dependent role for NLRP12 in GBM progression.

cancer biology↗

bioRxiv2025

InCytokine, an open-source software, reveals a TREM2 variant specific cytokine signature

Cytokine and chemokine profiling is central to understanding inflammatory processes and the mechanisms driving diverse diseases. We introduce InCytokine, an open-source tool for semiquantitative analysis of cytokine and chemokine data generated by protein array technologies. InCytokine features robust and modular image-processing workflows, including automated spot detection, template alignment, normalization, quality-control measures and quantitative intensity summarization to deliver consistent and reliable readouts from profiling assays. We evaluated InCytokine by profiling wild-type microglia, TREM2 knockout, and Alzheimers-associated TREM2 R47H variant cells in response of lipopolysaccharide and sulfatide exposure. Differential expression analysis revealed unique sulfatide-specific and genotype-specific cytokine signatures in TREM2 variants. We also report an intriguing modulation of DPP4 and a divergent expression pattern of ENA-78 in TREM2 variants in response to lipopolysaccharide and sulfatide treatment. Such distinct expression signatures raise the possibility that TREM2 variants may play a role in modulating inflammatory signaling relevant to cardio-metabolic and Alzheimers disease. These signatures were corroborated using transcriptional profiling of the same microglia cells, revealing also a good concordance between protein array and RNA sequencing technologies. Taken together, InCytokine is an interactive, user-friendly web application for rapid, reproducible, and scalable analysis of protein array data, proven to generate meaningful insights for drug and biomarker discovery campaigns in pharmaceutical settings.

bioinformatics↗

bioRxiv2024

HIV-1 infection is associated with depletion of germinal center B cells and a decrease in IgA+ plasma cells in the GI tract

Gastrointestinal (GI) B cells and plasma cells (PCs) are critical to mucosal homeostasis and the host response to HIV-1 infection. Here, high resolution mapping of human B cells and PCs sampled from the colon and ileum during both viremic and suppressed HIV-1 infection identified a reduction in germinal center (GC) B cells and follicular dendritic cells (FDCs) during HIV-1 viremia. IgA+ PCs are the major cellular output of intestinal GCs and were significantly reduced during viremic HIV-1 infection. PC-associated transcriptional perturbations, including type I interferon signaling, persisted in antiretroviral therapy (ART)-treated individuals, suggesting ongoing disruption of the intestinal immune milieu during ART. GI humoral immune perturbations were associated with changes in the intestinal microbiome composition and systemic inflammation. These findings highlight a key immune defect in the GI mucosa due to HIV-1 viremia. One Sentence SummaryIntestinal germinal center B cell reduction in HIV-1 infection linked to reduced IgA+ plasma cells and systemic inflammation.

immunology↗

bioRxiv2023

Brain map of aging-induced alterations in membrane ganglioside pattern

Recent efforts to develop comprehensive metabolome and proteome brain atlases for animal models have yielded significant progress. However, the ganglioside (GSs) profile of these models remains largely unexplored. As essential components of the brain, GSs play a crucial role in neuronal function. To address this gap in knowledge, we conducted an in-depth analysis of the young and adult rat brain, as well as its major brain regions, using ultra-high performance liquid chromatography and tandem mass spectrometry in positive and negative ion modes. We also analyzed GSs in cerebrospinal fluid (CSF) and serum from matched samples. Our findings indicate a shift in the ratio of a-series to b-series GSs with age, along with region-specific changes accompanied by aging. This could improve our understanding of brain aging and neurodegenerative diseases. Our study complements existing brain atlases of lipidome and protein expression and highlights the importance of further investigating the mechanisms underlying these GSs changes and the potential therapeutic implications of our findings.

neuroscience↗

bioRxiv2023

Apolipoprotein-based regulation of ganglioside metabolism upon secretase activity inhibition in iPSC-derived cerebral organoids

Beta and gamma-secretase inhibitors have been of pharmacological interest to reduce abeta (A{beta}) formation and aggregation, one of the defining characteristics of Alzheimers disease (AD). Recent research indicates that Apolipoprotein E (ApoE), a genetic risk factor for AD, can regulate secretase activity. Secretase inhibitor-induced elevation of neuronal membrane lipids has been documented in 2D models. Due to their enhanced ability to reproduce AD-like pathology and ease of performing the experimental intervention, we utilized a 3D cerebral organoid model derived from human pluripotent stem cells generated from an AD patient. We treated cerebral organoids carrying ApoE3 and ApoE4 variants with beta and gamma-secretase inhibitors to determine if organoids could reproduce the differences observed in the 2D model and if the alteration in secretase activity could affect the regulation of neuronal lipids synthesis in an ApoE-dependent manner. Ganglioside profiling was accomplished using liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) via selective reaction monitoring (SRM). The inhibitor administration elevated the levels of ganglioside and ceramide in ApoE4-derived organoids. Since gangliosides are known to enhance A{beta} fibrillogenesis, our study implies that reduction in secretase activity affects neuronal membrane architecture that could eventually aggravate AD, particularly in patients with the ApoE4 isoform. In addition, the ability of organoids to replicate results from other experimental models demonstrates their potential to improve translatability significantly.

neuroscience↗

bioRxiv2023

Myeloid cell influx into the colonic epithelium is associated with disease severity and non-response to anti-Tumor Necrosis Factor Therapy in patients with Ulcerative Colitis.

Ulcerative colitis (UC) is an idiopathic chronic inflammatory disease of the colon with sharply rising global prevalence. Dysfunctional epithelial compartment (EC) dynamics are implicated in UC pathogenesis although EC-specific studies are sparse. Applying orthogonal high-dimensional EC profiling to a Primary Cohort (PC; n=222), we detail major epithelial and immune cell perturbations in active UC. Prominently, reduced frequencies of mature BEST4+OTOP2+ absorptive and BEST2+WFDC2+ secretory epithelial enterocytes were associated with the replacement of homeostatic, resident TRDC+KLRD1+HOPX+ {gamma}{delta}+ T cells with RORA+CCL20+S100A4+ TH17 cells and the influx of inflammatory myeloid cells. The EC transcriptome (exemplified by S100A8, HIF1A, TREM1, CXCR1) correlated with clinical, endoscopic, and histological severity of UC in an independent validation cohort (n=649). Furthermore, therapeutic relevance of the observed cellular and transcriptomic changes was investigated in 3 additional published UC cohorts (n=23, 48 and 204 respectively) to reveal that non-response to anti-Tumor Necrosis Factor (anti-TNF) therapy was associated with EC related myeloid cell perturbations. Altogether, these data provide high resolution mapping of the EC to facilitate therapeutic decision-making and personalization of therapy in patients with UC.

immunology↗

bioRxiv2023

Gut-associated lymphoid tissue attrition associates with response to anti-α4β7 therapy in ulcerative colitis

Targeting the 4{beta}7-MAdCAM-1 axis with vedolizumab (VDZ) is a front-line therapeutic paradigm in ulcerative colitis (UC). However, mechanism(s) of action (MOA) of VDZ remain relatively undefined. Here, we examined three distinct cohorts of patients with UC (n=83, n=60, and n=21), to determine the effect of VDZ on the mucosal and peripheral immune system. Transcriptomic studies with protein level validation were used to study drug MOA using conventional and transgenic murine models. We found a significant decrease in colonic and ileal naive B and T cells and circulating gut-homing plasmablasts ({beta}7+) in VDZ-treated patients, pointing to gut-associated lymphoid tissue (GALT) targeting by VDZ. Murine Peyers patches (PP) demonstrated a significant loss cellularity associated with reduction in follicular B cells, including a unique population of epithelium-associated B cells, following anti-4{beta}7 antibody (mAb) administration. Photoconvertible (KikGR) mice unequivocally demonstrated impaired cellular entry into PPs in anti-4{beta}7 mAb treated mice. In VDZ-treated, but not anti-tumor necrosis factor-treated UC patients, lymphoid aggregate size was significantly reduced in treatment responders compared to non-responders, with an independent validation cohort further confirming these data. GALT targeting represents a novel MOA of 4{beta}7-targeted therapies, with major implications for this therapeutic paradigm in UC, and for the development of new therapeutic strategies.

immunology↗

bioRxiv2022

Domino-like Effect of C112R Mutation on APOE4 Aggregation and Its Suppression by Alzheimer's Disease Drug Candidate

BackgroundApolipoprotein E (ApoE) {varepsilon}4 genotype is the most prevalent risk factor for late-onset Alzheimers Disease (AD). Although ApoE4 differs from its non-pathological ApoE3 isoform only by the C112R mutation, the molecular mechanism of its proteinopathy is unknown. MethodsHere, we reveal the molecular mechanism of ApoE4 aggregation using a combination of experimental and computational techniques, including X-ray crystallography, site-directed mutagenesis, hydrogen-deuterium mass spectrometry (HDX-MS), static light scattering and molecular dynamics simulations. Treatment of ApoE {varepsilon}3/{varepsilon}3 and {varepsilon}4/{varepsilon}4 cerebral organoids with tramiprosate was used to compare the effect of tramiprosate on ApoE4 aggregation at the cellular level. ResultsWe found that C112R substitution in ApoE4 induces long-distance (>15 [A]) conformational changes leading to the formation of a V-shaped dimeric unit that is geometrically different and more aggregation-prone than the ApoE3 structure. AD drug candidate tramiprosate and its metabolite 3-sulfopropanoic acid induce ApoE3-like conformational behavior in ApoE4 and reduce its aggregation propensity. Analysis of ApoE {varepsilon}4/{varepsilon}4 cerebral organoids treated with tramiprosate revealed its effect on cholesteryl esters, the storage products of excess cholesterol. ConclusionsOur results connect the ApoE4 structure with its aggregation propensity, providing a new druggable target for neurodegeneration and ageing.

neuroscience↗

bioRxiv2020

Evolution of Antibody Immunity to SARS-CoV-2

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has infected 78 million individuals and is responsible for over 1.7 million deaths to date. Infection is associated with development of variable levels of antibodies with neutralizing activity that can protect against infection in animal models. Antibody levels decrease with time, but the nature and quality of the memory B cells that would be called upon to produce antibodies upon re-infection has not been examined. Here we report on the humoral memory response in a cohort of 87 individuals assessed at 1.3 and 6.2 months after infection. We find that IgM, and IgG anti-SARS-CoV-2 spike protein receptor binding domain (RBD) antibody titers decrease significantly with IgA being less affected. Concurrently, neutralizing activity in plasma decreases by five-fold in pseudotype virus assays. In contrast, the number of RBD-specific memory B cells is unchanged. Memory B cells display clonal turnover after 6.2 months, and the antibodies they express have greater somatic hypermutation, increased potency and resistance to RBD mutations, indicative of continued evolution of the humoral response. Analysis of intestinal biopsies obtained from asymptomatic individuals 4 months after coronavirus disease-2019 (COVID-19) onset, using immunofluorescence, or polymerase chain reaction, revealed persistence of SARS-CoV-2 nucleic acids and immunoreactivity in the small bowel of 7 out of 14 volunteers. We conclude that the memory B cell response to SARS-CoV-2 evolves between 1.3 and 6.2 months after infection in a manner that is consistent with antigen persistence.

immunology↗

bioRxiv2020

Intestinal inflammation modulates the expression of ACE2 and TMPRSS2 and potentially overlaps with the pathogenesis of SARS-CoV-2 related disease

The presence of gastrointestinal symptoms and high levels of viral RNA in the stool suggest active Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) replication within enterocytes. Here, in multiple, large cohorts of patients with inflammatory bowel disease (IBD), we have studied the intersections between Coronavirus Disease 2019 (COVID-19), intestinal inflammation and IBD treatment. A striking expression of ACE2 on the small bowel enterocyte brush border supports intestinal infectivity by SARS-CoV-2. Commonly used IBD medications, both biologic and non-biologic, do not significantly impact ACE2 and TMPRSS2 receptor expression in the uninflamed intestines. Additionally, we have defined molecular responses to COVID-19 infection that are also enriched in IBD, pointing to shared molecular networks between COVID-19 and IBD. These data generate a novel appreciation of the confluence of COVID-19- and IBD-associated inflammation and provide mechanistic insights supporting further investigation of specific IBD drugs in the treatment of COVID-19.

immunology↗