Biology subjects

Mathews, V.

Publications and source records attributed to Mathews, V..

5 recordsLinked to original sources

bioRxiv2026

Investigating the significance of iron levels in influencing megakaryocytic commitment in megakaryocyte-erythroid progenitors

AimThe present study investigated the significance of iron in regulating megakaryopoiesis, by a diet-based intervention in an in-vivo model. MethodsMale C57BL/6 mice, aged 4-5 weeks were fed on varying iron diets. Following sacrifice, blood samples collected in EDTA tubes were used to analyse haematological parameters, and iron content of liver and spleen was assessed by biochemical analyses. Megakaryocyte-erythroid progenitors (MEPs) were isolated from bone marrow by magnetic bead-based selection. RNA isolated from bone marrow cells and MEPs were used for gene expression analyses, and RNA Sequencing to identify differentially expressed genes (DEGs) and associated pathways. ResultsMice fed on an iron-deficient diet had reduced hepatic iron content after 5 weeks (p < 0.01), while both the hepatic and spleen iron content increased after 3 weeks in mice on an iron-rich diet (p < 0.05) and developed iron overloading. Hb and RBC counts increased (p < 0.05) in iron-rich mice and decreased in iron-deficient mice (p < 0.05), which also showed elevated platelet counts (p < 0.01). This may be explained by increased expression of Gata1, Tal1 (p < 0.01) Mds1 and Pdpk1 (p < 0.05) in bone marrow cells from iron-deficient mice. MEPs isolated from these mice showed elevated expression of genes associated with megakaryocytic differentiation, platelet functions, and genes encoding TGF-{beta}R1 and Smad 2,3 and 4. ConclusionsIron deficiency may activate TGF-{beta} signalling and downstream Smad-mediated transcriptional programs within MEPs. This may promote a shift in lineage commitment towards megakaryopoiesis through elevated expression of megakaryopoiesis related genes.

molecular biology↗

bioRxiv2025

AI-Guided Design and AKT3 Degradation Synergize to Enhance Bispecific and Trispecific CAR-T Cell Persistence and Overcome Antigen Escape

The structural design of chimeric antigen receptors (CARs) is critical for achieving robust and durable anti-tumor responses, particularly when targeting multiple antigens to prevent tumor antigen escape. However, increasing CAR complexity can introduce structural vulnerabilities, leading to antigen-independent T cell activation, activation-induced cell death, and reduced CAR-T cell persistence. To overcome these challenges, we designed 10,824 CAR molecules across diverse formats and screened 1,452 constructs in-vitro to develop an artificial intelligence model, termed CAR-Mediated Self-Destruction (CARMSeD), which predicts CAR designs susceptible to self-activation and dysfunction. Guided by CARMSeD and structural CAR-CAR interaction modeling, we identified optimized CAR architectures incorporating ICOS and 4-1BB co-stimulatory domains. Humanized bispecific CARs targeting CD20/CD19 and CD22/CD19 demonstrated superior anti-tumor efficacy and persistence both in-vitro and in various xenograft mice models. To further extend CAR-T cell persistence, we engineered bispecific CARs integrated with an AKT3-targeted PROTAC strategy. Targeted degradation of AKT3 enhanced anti-tumor potency, promoted memory T cell formation, and enabled sustained responses even under tumor rechallenge and CD19 antigen-loss conditions. Mechanistically, these effects were mediated by metabolic reprogramming involving FOXO4; notably, FOXO4-deficient CAR-T cells exhibited impaired long-term persistence. Leveraging these mechanistic insights, we developed a trispecific CAR-T cell platform incorporating a bispecific T cell engager (BiTE) targeting CD22/CD3, combined with AKT3 PROTACs. These trispecific CAR-T cells achieved potent tumor eradication, even against malignancies lacking both CD19 and CD20 expression. Collectively, this study presents a comprehensive strategy combining structure-based design, AI-guided screening, and targeted protein degradation to engineer next-generation bi and trispecific CAR-T cells with enhanced persistence, broad antigen coverage, and superior therapeutic durability.

cancer biology↗

bioRxiv2024

Investigating the influence of iron parameters in regulating platelet recovery in Apheresis Platelet Donors

IntroductionThe present study investigates changes in haematological parameters in the donor during apheresis and following donation. Effect of iron parameters in influencing platelet recovery was studied. MethodsBlood samples were collected in EDTA tubes for analyses of haematological parameters. Serum samples were isolated for estimation of iron parameters. ResultsHb, RBC count and Hct increased during apheresis, but no significant changes were observed after 48 hrs post donation. Platelet recovery rates increased from 78 % after 48 hours to > 100% on day 10 (p < 0.001). Ferritin, serum iron & Transferrin saturation initially increased and subsequently declined from day 7 post donation, which may influence platelet recovery. Recovery rates were also higher in donors with lower iron stores. ConclusionsChanges in haematological parameters during plateletpheresis are transient and optimal time required for platelet recovery is dependent on pre-donation counts. Recovery of platelet counts may be positively regulated by donor iron parameters.

molecular biology↗

bioRxiv2024

Targeting Metabolic Dependencies in Acute Myeloid Leukemia: A Dual Strategy using Arsenic Trioxide and Artesunate.

Acute myeloid leukemia (AML) remains a difficult disease to cure despite recent advances. Off-target side effects of therapy, especially prolonged cytopenia, lead to significant morbidity and mortality. There is an increased recognition that in AML, there is a potentially vulnerable dependence on OXPHOS metabolism, more so in the leukemia stem cell compartment (AML-LSC) that could be exploited. Drug re-purposing screens have suggested the possible role of artesunate (ART) in inhibiting mitochondrial respiration and arsenic trioxide (ATO) in inhibiting glycolysis. Here, we explore the potential of using a combination of ART and ATO to treat AML. Through in-vitro and in-vivo studies, we demonstrate the potential of this combination along with hypo-methylating agents and other mitocans, such as BCL-2 inhibitor venetoclax, to be used in the treatment of AML with minimal off-target effect on normal hematopoietic stem cells (HSC). These observations warrant further exploration of such novel combinations in clinical trials.

cancer biology↗

bioRxiv2020

Arsenic trioxide resistance in acute promyelocytic leukemia: More to it than PML mutations

Acquired genetic mutations can confer resistance to arsenic trioxide (ATO) in the treatment of acute promyelocytic leukemia (APL). However, such resistance-conferring mutations are rare and do not explain the majority of disease recurrence seen in the clinic. We have generated a stable ATO resistant promyelocytic cell from a ATO sensitive NB4 cell line. We also noted that another ATRA resistant cell line (UF1) was cross resistant to ATO. We have characterized these resistant cell lines and observed that they significantly differed in their immunophenotype, drug transporter expression, drug resistance mutation profile and were also cross-resistant to other conventional chemotherapeutic agents. The NB4 derived resistant cell line had the classical A216V PML-B2 domain mutation while the UF1 cell line did not. Gene expression profiling revealed prominent dysregulation of the cellular metabolic pathways in the resistant cell lines. Glycolytic inhibition by 2-DG was efficient and comparable to the standard of care (ATO) in targeting the sensitive APL cell lines and was also effective in the in vivo transplantable APL mouse model; however, it did not affect the ATO resistant cell lines. The survival of the resistant cell lines was significantly affected by compounds targeting the mitochondrial respiration irrespective of the existence of ATO resistance-conferring genetic mutations. Our data demonstrate the addition of mitocans can overcome ATO resistance. We further demonstrated that the combination of ATO and mitocans has the potential in the treatment of non-M3 AML and the translation of this approach in the clinic needs to be explored further. Key pointsO_LIMetabolic rewiring promotes ATO resistance, which can be overcome by targeting mitochondrial oxidative phosphorylation. C_LIO_LICombination of ATO and mitocans can be exploited as a potential therapeutic option for relapsed APL and in non-M3 AML patients. C_LI

cancer biology↗