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Biology subjects

Mir, R. A.

Publications and source records attributed to Mir, R. A..

6 recordsLinked to original sources

A crucial role for PIH1D1 in modulating p53 stability via the R2TP complex

The R2TP is a multimeric protein complex consists of RUVBL1, RUVBL2, PIH1D1, and RPAP3, and it is known to functions as a specialized co-chaperone. We hypothesize that PIH1D1 recognizes p53 and stabilizes it via R2TP complex. Upon successful completion of this study, innovative mechanism has been found for the interaction and stabilization of p53 and hence govern the cell cycle. Upon interaction between p53 and PIH1D1 protein, p53 is stabilized by PIH1D1 protein, without affecting its C-terminal domain. We have also observed that p53 protein levels were affected after the alteration in expression levels of PIH1D1. Based on the finding, we suggest that the R2TP complex stabilizes and regulates P53. Therefore, this novel method will work as a flashpoint to restore the function of p53 in cancer cells, controlling cancer and cell cycle progression.

biochemistry↗

Dual Preconditioned Mesenchymal Stem Cells-Derived Culture Conditioned Media Augment Immunomodulation and Drive Metabolic Reprogramming in Acute Graft-versus-Host Disease

BackgroundThe toxicity associated with conventional conditioning regimens limits treatment outcomes in autoimmune disorders such as acute graft-versus-host disease (aGVHD). Developing effective adjunctive interventions to restore immune balance is therefore essential. This study investigated the immunomodulatory potential of mesenchymal stem cells (MSCs)-derived culture-conditioned media (CCM) from naive and preconditioned MSCs-hypoxic (MSCsHYP), apoptotic (MSCsAPO), and dual preconditioned (MSCsHYP+APO) in aGVHD. MethodsHuman MSCs isolated from bone marrow and Whartons Jelly were preconditioned under hypoxia (1% O2), apoptosis (1 {micro}M staurosporine, 24 h), or both. The immunoregulatory and antioxidant properties of their CCM were evaluated through T-cell proliferation assays, Treg induction, macrophage polarization, mitochondrial function, and T-cell bioenergetics. Comparative proteomic profiling of CCM from WJ-MSCs and WJ-MSCsHYP+APO co-cultured with aGVHD patient-derived activated PBMNCs was performed using LC-MS/MS, alongside in vivo validation in a chemotherapy-induced aGVHD murine model. ResultsWJ-MSCsHYP+APO-CCM exhibited superior immunomodulatory efficacy, suppressing T-cell proliferation, promoting Treg and Th2/Th9 differentiation, and driving M2 macrophage polarization. It reduced mitochondrial ROS, enhanced mitochondrial polarization, and shifted T-cell metabolism from glycolysis toward oxidative phosphorylation. Proteomic analysis revealed modulation of IL-12, IL-17, and JAK-STAT pathways, along with regulation of complement, coagulation, and metabolic cascades. Interaction with immune cells further enhanced its antioxidant and tissue-reparative properties via extracellular matrix remodeling. ConclusionDual preconditioning under hypoxia and apoptosis amplifies the immunomodulatory, antioxidant, and reparative efficacy of WJ-MSC-CCM, offering a potent non-cellular therapeutic strategy for aGVHD management. GRAPHICAL ABSTRACTImmunomodulatory and immune metabolic reprogramming potential of naive and preconditioned MSCs (MSCs, MSCsHYP, MSCsAPO, MSCsHYP+APO) derived CCM in Acute GVHD (created using Biorender.com) O_FIG O_LINKSMALLFIG WIDTH=95 HEIGHT=200 SRC="FIGDIR/small/686182v1_ufig1.gif" ALT="Figure 1"> View larger version (26K): org.highwire.dtl.DTLVardef@f7ed73org.highwire.dtl.DTLVardef@1063015org.highwire.dtl.DTLVardef@13ed827org.highwire.dtl.DTLVardef@e103c0_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Predictive Modeling of acute Graft-versus-Host-Disease using Machine Learning on Immune Cell and Cytokine Profiles at Engraftment

BackgroundAcute Graft-versus-Host-Disease (aGvHD) is a major immune complication following allogenic hematopoietic stem cell transplantation (Allo-HSCT), initiated by conditioning regimen-associated tissue damage. It involves the complex interplay of immune cells and cytokines. Our study aims to leverage machine learning (ML) algorithms on the immune and cytokine profile of Allo-HSCT recipients to develop biomarker-based classification models to predict the onset of aGvHD at the time of engraftment. Materials and MethodsSeventy patients diagnosed with hematological disorders who had undergone Ist Allo-HSCT were recruited from All India Institute of Medical Sciences, New Delhi, India. Peripheral blood (PB) was collected from the patients at the time of engraftment, and the immune cell subtypes and cytokine profiles were analyzed using flow cytometry and ELISA respectively. The individual cell counts were then processed using basic ML models, including support vector classifier with RBF kernel, Decision Tree, and Random Forest, chosen for their mathematical simplicity and feature importance advantage of Decision Trees and Random Forests. Various data settings were utilized in the study: combined immune and cytokine counts, immune cell counts only, cytokine counts only, T-cell counts only, NK cell counts only, dendritic cell counts only, and B-cell counts only. These configurations were selected to investigate how different data sets impact the prediction of aGvHD before its onset. ResultsAt the engraftment flow cytometric analysis of reconstituted lymphocytes in patients who developed aGvHD revealed that there was a remarkable decrease in the ratio of CD4+/CD8+ T-cell and Tregs, with an increase in the cytotoxic regulatory NK-cell, dendritic cells, and B-cell. The levels of pro-inflammatory cytokines (IFN-{gamma}, IL-1{beta}, IP-10, TNF-, IL-17, IL-12p70, MIP-1, MIP-1{beta}, RANTES), and Th17-and Th1-cells were elevated with consequent decline of the levels of anti-inflammatory cytokine IL-10, IL-2, IL-4 and Th2-, Th9-cells. Machine learning based on 48 parameters [all immune cell subsets n=34 and all cytokines (n=14)]. The correlation heat map shows a higher correlation of aGvHD with the cytokine profile with or without immune cells (accuracy: 1), T-cell alone (accuracy: 0.96); NK-cell alone (accuracy: 0.93); dendritic cells alone (accuracy: 0.90), B-cell alone (accuracy: 0.86). ConclusionThe current models classify perfectly, indicating the potential for a ML algorithm in predicting the onset of aGvHD. However, a study with a larger sample size is required to validate these classification models and mitigate the risk of overfitting observed due to the consistently high performance. The study also highlights the potential of cytokine profiles as a viable alternative to T-cell counts, as evidenced by the correlation heat map and classifier models. These findings provide valuable insights into dataset requirements and future directions for integrating ML models into aGvHD prediction.

immunology↗

Hypoxia-Mediated Molecular Interactions of Tissue-Specific Mesenchymal Stem Cells Drive Metabolic Reprogramming and Immunomodulation in Acute Graft-versus-Host Disease

BackgroundMesenchymal stem cells (MSCs) mediate immunomodulation through various mechanisms, including apoptosis, efferocytosis, and mitochondrial transfer. Our study investigates the impact of hypoxia preconditioning on the immune metabolic reprogramming and immunomodulatory potential of MSCs in acute graft-versus-host disease (aGVHD). Additionally, we explored the differential immunomodulatory effects of tissue-specific MSCs, specifically bone marrow (BM) and Whartons Jelly (WJ), and elucidated the mechanisms underlying variability in their therapeutic efficacy. MethodsMSCs were isolated from BM and WJ and subjected to hypoxia preconditioning. Their immunometabolic programming potential was assessed by evaluating T-cell proliferation, regulatory T-cell (Treg) induction, effector T-cell differentiation toward Th2, Th9 phenotypes, and macrophage polarization, T-cell bioenergetics in the direct co-culture systems. ResultsWJ-MSCsHYP exhibited superior immunomodulatory properties compared to BM-MSCsHYP, by inhibiting T-cell proliferation, enhancing Treg induction, and promoting anti-inflammatory macrophage polarization. WJ-MSCsHYP demonstrated enhanced mitochondrial transfer to T-cell, improving mitochondrial health, reducing ROS, and promoting oxidative phosphorylation, leading to immune homeostasis. Unlike BM-MSCs, WJ-MSCs exhibited higher rates of apoptosis, which facilitated immune modulation through mechanisms independent of efferocytosis. ConclusionOur findings highlight that WJ-MSCsHYP is a superior candidate for aGVHD by utilizing apoptosis, mitochondrial transfer, and metabolic reprogramming to achieve immune regulation.

immunology↗

Decoding Prognostic Markers Bioinformatics Insights into PIH1D1 and p53 in Children's Brain Cancer

Genetic alterations in normal brain cells lead to the development of brain tumors (BT). The incidence of newly diagnosed cases is on the rise over time. Understanding the molecular biology of pediatric brain tumors is crucial for advancing novel therapeutic approaches to prevent or effectively manage this disease. The R2TP complex, a conserved co-chaperone from yeast to mammals, including RUVBL1, RUVBL2, PIH1D1, and RPAP3 in humans, plays a crucial role in the assembly and maturation of various multi-subunit complexes. This study evaluates the expression of PIH1D1 and p53 in pediatric brain cancers using The Cancer Genome Atlas (TCGA) data through the UALCAN platform--a novel, user-friendly resource for cancer OMICS data analysis. Our analysis revealed elevated expression levels of PIH1D1 in pediatric brain tumors across all age groups compared to normal tissues, suggesting its potential as an early detection marker and a prognostic indicator. Additionally, P53 emerged as a promising target for brain tumor treatment, warranting exploration for age-specific applications. The Venn Diagram analysis further delineated key genes within the PIH1D1 and P53 networks, providing insights into the genetic landscape of childhood brain cancer. Despite these findings, the study has limitations, primarily relying on bioinformatics databases. Future research will incorporate clinical tissues and cell lines in in vivo and in vitro experiments to unravel the mechanistic roles of PIH1D1 and p53 in brain tumors. This comprehensive approach bridges bioinformatics and clinical exploration, contributing to a holistic understanding of pediatric brain cancer molecular biology and paving the way for targeted therapeutic interventions.

bioinformatics↗

Cross-neutralization of SARS-CoV-2 by HIV-1 specific broadly neutralizing antibodies and polyclonal plasma

Cross-reactive epitopes (CREs) are similar epitopes on viruses that are recognized or neutralized by same antibodies. The S protein of SARS-CoV-2, similar to type I fusion proteins of viruses such as HIV-1 envelope (Env) and influenza hemagglutinin, is heavily glycosylated. Viral Env glycans, though host derived, are distinctly processed and thereby recognized or accommodated during antibody responses. In recent years, highly potent and/or broadly neutralizing human monoclonal antibodies (bnAbs) that are generated in chronic HIV-1 infections have been defined. These bnAbs exhibit atypical features such as extensive somatic hypermutations, long complementary determining region (CDR) lengths, tyrosine sulfation and presence of insertions/deletions, enabling them to effectively neutralize diverse HIV-1 viruses despite extensive variations within the core epitopes they recognize. As some of the HIV-1 bnAbs have evolved to recognize the dense viral glycans and cross-reactive epitopes (CREs), we assessed if these bnAbs cross-react with SARS-CoV-2. Several HIV-1 bnAbs showed cross-reactivity with SARS-CoV-2 while one HIV-1 CD4 binding site bnAb, N6, neutralized SARS-CoV-2. Furthermore, neutralizing plasma antibodies of chronically HIV-1 infected children showed cross neutralizing activity against SARS-CoV-2. Collectively, our observations suggest that human monoclonal antibodies tolerating extensive epitope variability can be leveraged to neutralize pathogens with related antigenic profile. ImportanceIn the current ongoing COVID-19 pandemic, neutralizing antibodies have been shown to be a critical feature of recovered patients. HIV-1 bnAbs recognize extensively diverse cross-reactive epitopes and tolerate diversity within their core epitope. Given the unique nature of HIV-1 bnAbs and their ability to recognize and/or accommodate viral glycans, we reasoned that the glycan shield of SARS-CoV-2 spike protein can be targeted by HIV-1 specific bnAbs. Herein, we showed that HIV-1 specific antibodies cross-react and neutralize SARS-CoV-2. Understanding cross-reactive neutralization epitopes of antibodies generated in divergent viral infections will provide key evidence for engineering so called super-antibodies (antibodies that can potently neutralize diverse pathogens with similar antigenic features). Such cross-reactive antibodies can provide a blueprint upon which synthetic variants can be generated in the face of future pandemics.

immunology↗