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Biology subjects

Azmi, I.

Publications and source records attributed to Azmi, I..

3 recordsLinked to original sources

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↗

Activation of cGAS-STING signaling pathway during HCV infection

Hepatitis C virus (HCV) is a major global health issue, infecting over 170 million people worldwide and leading to severe liver diseases, including cirrhosis and hepatocellular carcinoma. The ability of HCV to persist and cause chronic infection is partly due to its evasion of the hosts innate immune responses, particularly those mediated by the RIG-I-MAVS pathway, which is critical for antiviral defense. Studies have shown the crucial role genome sensing of DNA viruses by cyclic GMP-AMP synthase (cGAS) followed cGAMP production and activation of downstream effector STING (stimulator of interferon genes) to induce IFN-{beta}, however it is not understood in RNA viruses specially in HCV infection. In this study, we explored first time the mechanism of the cGAS-STING pathway in the context of HCV infection, specifically using the JFH-1 strain of HCV (genotype 2a). We observed that cGAS expression is significantly upregulated during the early HCV infection, leading to the production of the second messenger cyclic GMP-AMP (cGAMP), which in turn activates STING. This activation results in the significant induction of type I interferon responses, particularly interferon-{beta} (IFN-{beta}), which is essential for mounting an effective antiviral response. Moreover, our results demonstrated the translocation of cGAS and STING with cellular organelles such as the endoplasmic reticulum (ER) and mitochondria. This suggests that the cGAS-STING pathway is intricately linked with other cellular signaling networks in detecting and responding to HCV infection. Furthermore, knockdown experiments targeting cGAS, STING and RIG-I revealed that these proteins play a crucial role in suppressing HCV replication, underscoring their potential as therapeutic targets. These findings provide valuable insights into the molecular mechanisms of the cGAS-STING pathway in mediating the innate immune response against HCV. Understanding this pathways role in the immune defense against HCV opens up new possibilities for therapeutic strategies aimed at enhancing the hosts antiviral immunity and potentially developing new treatments for chronic HCV infection.

microbiology↗

Obesity impairs therapeutic efficacy of mesenchymal stem cells by inhibiting cardiolipin-dependent mitophagy and intercellular mitochondrial transfer in mouse models of airway allergic inflammation

Mesenchymal stem cell (MSC) transplantation alleviates metabolic defects in diseased recipient cells by intercellular mitochondrial transport (IMT). However, the effect of host metabolic conditions on MSCs in general, and IMT in particular, has largely remained unexplored. This study has identified a molecular pathway that primarily governs the metabolic function and IMT of MSCs. We found underlying mitochondrial dysfunction, impaired mitophagy, and reduced IMT in MSCs derived from high-fat diet (HFD)-induced obese mice (MSC-Ob). Mechanistically, MSC-Ob failed to sequester their damaged mitochondria into LC3-dependent autophagosomes due to decrease in mitochondrial cardiolipin content, which we propose as a putative mitophagy receptor for LC3 in MSCs. Functionally, MSC-Ob exhibited diminished potential to rescue metabolic deficits and cell death in stress-induced epithelial cells. In a small molecule screen, we found pyrroloquinoline quinone (PQQ) as a regulator of mitophagy and IMT. Long-term culture of MSC-Ob with PQQ (MSC-ObPQQ) restored cardiolipin content and sequestration of mitochondria to autophagosomes with concomitant activation of mitophagy. Upon co-culture, MSC-ObPQQ rescued cell death in stress-induced epithelial cells by enhancing IMT. The beneficial effect of PQQ was also evident in MSCs derived from human subjects in an in vitro model. In two independent mice models, the transplantation of MSC-ObPQQ restored IMT to airway epithelial cells, improved their mitochondrial metabolism and attenuated features of allergic airway inflammation (AAI). However, unmodulated MSC-Ob failed to do so. In summary, we uncover the molecular mechanism leading to the therapeutic decline of obese-derived MSCs and highlight the importance of pharmacological modulation of these cells for therapeutic intervention.

cell biology↗