Biology subjects

Jha, R.

Publications and source records attributed to Jha, R..

8 recordsLinked to original sources

bioRxiv2026

Sanjeevani: A manually curated anti-cancerous phytochemical database integrated with downstream analysis tools.

BackgroundCancer continues to pose a massive global health burden. While plant-derived phytochemicals offer promising therapeutic leads, existing natural product databases often lack cancer specificity, dataset downloadability, and integrated screening tools. MethodsWe developed Sanjeevani, an integrative web platform cataloguing 4,823 curated anticancer phytochemicals. Using a balanced dataset of 9,646 molecules, we trained Support Vector Machine (SVM), Random Forest, and K-Nearest Neighbours classifiers using a hybrid feature representation of RDKit descriptors and 2048-bit ECFP4 fingerprints. The platform also integrates AutoDock Vina for web-based molecular docking for binding affinity, poses prediction and ADMET-AI for pharmacokinetics estimation. ResultsThe SVM model demonstrated the strongest predictive capability, achieving a top test accuracy of 0.966 and a ROC-AUC of 0.992. Benchmarking across five docking tools confirmed that AutoDock Vina successfully balanced computational automation with literature-consistent binding affinity replication. The final architecture provides rapid interactive 2D/3D visualizations integrated with downstream analysis tools. ConclusionSanjeevani provides an open-access, one-stop pipeline that bridges the gap between raw natural product data and actionable computational screening, accelerating natural product-based oncology drug discovery. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=80 SRC="FIGDIR/small/732344v1_ufig1.gif" ALT="Figure 1"> View larger version (17K): org.highwire.dtl.DTLVardef@77183borg.highwire.dtl.DTLVardef@d7e465org.highwire.dtl.DTLVardef@1d3dfd7org.highwire.dtl.DTLVardef@10cc94d_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗

bioRxiv2026

Characterization of effects of a neurotropic murine coronavirus infection on Alzheimer's disease neuropathology of 5xFAD mice

BackgroundRecent studies revealed key immunological mechanisms within the central nervous system (CNS) that contribute to Alzheimers disease pathology. Additionally, analyses of human AD datasets have also associated viral encephalitis exposure (i.e., viral-induced neuroinflammation) with the development of AD and dementia, highlighting the need to better understand how viral encephalitis and neuroimmune mechanisms within the brain may impact AD pathologies such as A{beta} plaque deposition. Intracranial infection of susceptible mice with the neurotropic JHM strain of murine coronavirus (JHMV) results in acute encephalomyelitis characterized by viral infection of glia and a robust inflammatory response comprised of monocytes/macrophages and T cells that aid in controlling viral replication. MethodsTo determine how coronavirus-induced encephalitis may impact established A{beta} plaque deposition, we intracranially inoculated JHMV into aged 5xFAD model of amyloidosis. We utilize immunohistochemical and biochemical analysis to assess the impact on existing A{beta} pathology. We also utilize spatial transcriptomic imaging to explore how viral encephalitis affects cellular responses to plaque pathology with single-cell resolution. ResultsIn aged 5xFAD mice, JHMV-induced encephalitis at 12 days p.i. resulted in minimal changes to overall A{beta} protein within the brain. However, viral encephalitis induces CD4+ and CD8+ T cell infiltration and more Lgals3/MAC2-expressing macrophages surrounding dense-core A{beta} plaques, which appear more compacted in JHMV-infected 5xFAD brains compared to uninfected 5xFAD controls. We compared gene expression within JHMV-infected 5xFAD mice and uninfected controls to identify distinct cellular responses to A{beta} plaques that differed. Utilizing differential gene expression and pathway analysis, we found that viral encephalitis increased the proportion of myeloid cells in the 5xFAD brain, which also showed down-regulated disease-associated (DAM) pathways involving A{beta} clearance, response to lipids, and macrophage activation within the post-encephalitis 5xFAD brains. ConclusionsTogether, these findings suggest an attenuated myeloid cell response to A{beta} plaque burden in 5xFAD mice following acute viral encephalitis. Future experiments aim to further dissect inflammatory mechanisms between infiltrating myeloid cells, T cells, and the progression of A{beta} and tau pathology. Data derived from these experiments will further elucidate the viral-induced neuroimmune mechanisms that affect AD pathology and offer an opportunity to determine how these neuropathologic changes, such as subsequent neuronal damage, occur.

neuroscience↗

bioRxiv2023

Designer small molecule control system based on Minocycline induced disruption of protein-protein interaction.

A versatile, safe, and effective small-molecule control system is highly desirable for clinical cell therapy applications. Therefore, we developed a two-component small-molecule control system based on the disruption of protein-protein interactions using minocycline, an FDA-approved antibiotic with wide availability, excellent bio-distribution, and low toxicity. The system comprises an anti-minocycline single-domain antibody (sdAb) and a minocycline-displaceable cyclic peptide. Here we show how this versatile system can be applied to OFF-switch split CAR systems (MinoCAR) and universal CAR adaptors (MinoUniCAR) with reversible, transient, and dose-dependent suppression; to a tunable T cell activation module based on MyD88/CD40 signaling; to a controllable cellular payload secretion system based on IL-12 KDEL retention and as a cell/cell inducible junction. This work represents an important step forward in the development of a remote-controlled system to precisely control the timing, intensity, and safety of therapeutic interventions. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=125 SRC="FIGDIR/small/553207v1_ufig1.gif" ALT="Figure 1"> View larger version (57K): org.highwire.dtl.DTLVardef@1a16d73org.highwire.dtl.DTLVardef@1189ceeorg.highwire.dtl.DTLVardef@e70a57org.highwire.dtl.DTLVardef@580fa9_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

bioRxiv2022

Divergent MEK/ERK and AMPK signaling dictate lipogenic plasticity and dependence on fatty acid synthesis in Glioblastoma

Deregulated de novo lipid synthesis (DNLS) is a potential druggable vulnerability in Glioblastoma (GBM), a highly lethal and incurable cancer. Yet the molecular mechanisms that determine susceptibility to DNLS-targeted therapies remain unknown, and the lack of brain-penetrant inhibitors of DNLS has prevented their clinical evaluation as GBM therapeutics. Here, we report that YTX-7739, a clinical-stage, brain-penetrant inhibitor of stearoyl CoA desaturase (SCD), triggers lipotoxicity in patient-derived GBM stem-like cells (GSCs) and inhibits fatty acid desaturation in GSCs orthotopically implanted in mice. When administered as a single agent, or particularly in combination with the first line GBM chemotherapy, Temozolomide (TMZ), YTX-7739 showed therapeutic efficacy in orthotopic GSC mouse models owing to its lipotoxicity and its ability to impair DNA damage repair. Leveraging genetic, pharmacological, and physiological manipulation of key signaling nodes in gliomagenesis, we uncover that aberrant MEK/ERK signaling and its repression of the energy sensor AMP-activated protein kinase (AMPK) primarily drives therapeutic vulnerability to SCD and other DNLS inhibitors. Conversely, AMPK activation mitigates lipotoxicity and renders GSCs impervious to the loss of DNLS, both in culture and in vivo, by decreasing the saturation state of phospholipids and diverting toxic lipids into lipid droplets. Altogether, our findings reveal mechanisms of metabolic plasticity in GSCs and provide a framework for rational integration of DNLS-targeted therapies for the treatment of GBM.

cancer biology↗

bioRxiv2021

Three-dimensional microenvironment regulates gene expression, function, and tight junction dynamics of iPSC-derived blood-brain barrier microvessels

The blood-brain barrier (BBB) plays a pivotal role in brain health and disease. In the BBB, brain microvascular endothelial cells (BMECs) are connected by tight junctions which regulate paracellular transport, and express specialized transporter systems which regulate transcellular transport. However, existing in vitro models of the BBB display variable physiological accuracy across a wide range of characteristics including gene/protein expression and barrier function. Here, we use an isogenic family of fluorescently-labeled iPSC-derived BMEC-like cells (iBMECs) and brain pericyte-like cells (iPCs) within two-dimensional confluent monolayers (2D) and three-dimensional (3D) tissue-engineered microvessels to explore how 3D microenvironment regulates gene expression and function of the in vitro BBB. We show that 3D microenvironment (shear stress, cell-ECM interactions, and cylindrical geometry) increases BBB phenotype and endothelial identity, and alters angiogenic and cytokine responses in synergy with pericyte co-culture. Tissue-engineered microvessels incorporating junction-labeled iBMECs enable study of the real-time dynamics of tight junctions during homeostasis and in response to physical and chemical perturbations.

bioengineering↗

bioRxiv2021

CD49a Identifies Polyfunctional Memory CD8 T cell Subsets that Persist in the Lungs after Influenza Infection

CD8 T cell memory offers critical antiviral protection, even in the absence of neutralizing antibodies. The paradigm is that CD8 T cell memory within the lung tissue consists of a mix of circulating TEM cells and non-circulating TRM cells. However, based on our analysis, the heterogeneity within the tissue is much higher, identifying TCM, TEM, TRM, and a multitude of populations which do not perfectly fit these classifications. Further interrogation of the populations shows that TRM cells that express CD49a, both with and without CD103, have increased and diverse effector potential compared with CD49a negative populations. These populations function as a one-man band, displaying antiviral activity, chemokine production, release of GM-CSF, and the ability to kill specific targets in vitro with delayed kinetics compared with effector CD8 T cells. Together, this study establishes that CD49a defines multiple polyfunctional CD8 memory subsets after clearance of influenza infection, which act to eliminate virus in the absence of direct killing, recruit and mature innate immune cells, and destroy infected cells if the virus persists. Contribution to the fieldProtection from previously seen infections requires specialized immune memory cells properly positioned throughout the body to combat the newly invading pathogen. In the case of re-exposure to influenza virus, CD8 T cells resident within the respiratory tract (TRM) are critical for eliminating the virus. Previously, TRM were viewed as mostly homogenous, with a limited range of immune functions. In this study, lung TRM were compared with circulating memory CD8 T cells transiently present within the lung, to define the breadth of their effector capabilities. Using TRM defining surface proteins CD49a and CD103 to identify different memory CD8 T cell subsets, gene and protein expression were evaluated. In addition to demonstrating higher levels of diversity than previously reported, multiple polyfunctional subsets were identified. This polyfunctionality was primarily associated with cell populations expressing CD49a, and these cells produced multiple antiviral factors, chemokines to recruit other immune cells, a growth factor associated with improved antigen presenting cell function, and cytolytic granules. Functional assays further demonstrated killing of target cells by TRM. This study paints a more holistic, complete picture of the phenotype and functions of lung CD8 T cells after viral infection, revealing CD49a as a marker of cells with high effector capacity.

immunology↗

bioRxiv2019

Confirmation of local transmission of Orientia tsutsugamushi during scrub typhus outbreaks in Nepal

BackgroundScrub typhus is a severely ignored tropical disease and a leading cause of undifferentiated febrile illness worldwide caused by infection of an obligate intracellular bacteria Orientia tsutsugamushi. It has been rapidly expanding in South Asian countries, although clear epidemiological information is not available from Nepal. After the 2015 earthquake in Nepal, a sudden upsurge in scrub typhus cases was reported. The objective of this study was to investigate scrub typhus and its causative agents in human, rodent and chigger mites to better understand the ongoing transmission ecology. MethodsScrub typhus cases with confirmed diagnosis throughout the country were included in the analysis. Studies were concentrated in the Chitwan district, the site of a major outbreak in 2016. Additional country-wide data from 2015 to 2017 was made available from the government database to analyse the disease distribution using geographical mapping. ResultsDuring 2015-2017, 1,239 scrub typhus cases were confirmed with the largest outbreak occurring in 2016 with 831 (67.1%) cases. The remainder 267 cases were reported in 2017. The case fatality rate was 5.7% in 2015 and declined to 1.1% in 2017. Nationwide outbreak of scrub typhus was identified as the cases were found from 52 of the 75 districts of Nepal. A seasonal trend was observed with a peak during August and September (p = 0.01). In addition to the human cases, the presence of O. tsutsugamushi was also confirmed in rodents and chigger mites from the outbreak areas of southern Nepal. ConclusionThe detection of O. tsutsugamushi in human, rodent, and chigger mites from outbreak locations and wide-spread reports of scrub typhus throughout the country over two years confirms the ongoing transmission of O. tsutsugamushi with a firmly established ecology in Nepal. The countrys health system needs to be strengthened for systematic surveillance, early outbreaks detection, and immediate response actions including treatment and preventive measures. Author SummaryScrub typhus is a disease caused by a bacteria called Orientia tsutsugamushi and transmitted to people through bites of infected chiggers (larval mites). After the 2015 Gorkha earthquake in Nepal, a sudden upsurge in scrub typhus cases was reported with repeated outbreaks from different parts of the country. This study has documted epidemiology of scrub typhus and its causative agents in human, rodent and chigger mites confimring the local transmission O. tsutsugamushi with a firmly established ecology in Nepal. The local transmission of the diseases from most parts of the country demands strengthening for systematic surveillance, early outbreaks detection, and immediate response actions including treatment and preventive measures.

pathology↗

bioRxiv2017

Combinatorial Regulation Of The Balance Between Dynein Microtubule End Accumulation And Initiation Of Directed Motility

Cytoplasmic dynein is involved in a multitude of essential cellular functions. Dyneins activity is controlled by the combinatorial action of several regulators. The molecular mechanism of this regulation is poorly understood. Using purified proteins, we reconstitute the regulation of the human dynein complex by three prominent regulators on dynamic microtubules in the presence of end binding proteins (EBs). We find that dynein can be in biochemically and functionally distinct pools: either passively tracking dynamic microtubule plus-ends in an EB-dependent manner or moving processively towards minus ends in an adaptor protein-dependent manner. Whereas both dynein pools share the dynactin complex, they have opposite preferences for binding other regulators, either the adaptor protein Bicaudal D2 (BicD2) or the multifunctional regulator Lisencephaly-1 (Lis1). Remarkably, dynactin, but not EBs, strongly biases motility initiation locally from microtubule plus ends by autonomous plus end recognition. BicD2 and Lis1 together control the overall efficiency of motility initiation. Our study provides insight into the mechanism of dynein activity regulation by dissecting the distinct functional contributions of the individual members of a dynein regulatory network.

cell biology↗