Nanjing Calmhome Cell & Gene Engineering Institute Co., Ltd.

Chimeric antigen receptor T (CAR-T) cell therapy holds promise for cancer treatment, but its efficacy is often hindered by metabolic constraints in the tumor microenvironment. This study investigates the role of glutamine in enhancing CAR-T cell function against ovarian cancer.

Metabolomic profiling of blood samples from ovarian cancer patients treated with MSLN-CAR-T cells was conducted to identify metabolic changes. In vitro, glutamine pretreatment was applied to CAR-T cells, and their proliferation, CAR expression, tumor lysis, and cytokine production (TNF-α, IFN-γ) were assessed. Mechanistic studies focused on the mTOR-SREBP2 pathway and its effect on HMGCS1 expression, membrane stability and immune synapse formation. In vivo, the antitumor effects and memory phenotype of glutamine-pretreated CAR-T cells were evaluated.

Elevated glutamine levels were observed in the blood of ovarian cancer patients who responded to MSLN-CAR-T cell treatment. Glutamine pretreatment enhanced CAR-T cell proliferation, CAR expression, tumor lysis, and cytokine production. Mechanistically, glutamine activated the mTOR-SREBP2 pathway, upregulating HMGCS1 and promoting membrane stability and immune synapse formation. In vivo, glutamine-pretreated CAR-T cells exhibited superior tumor infiltration, sustained antitumor activity, and preserved memory subsets.

Our findings highlight glutamine-driven metabolic rewiring via the mTOR-SREBP2-HMGCS1 axis as a strategy to augment CAR-T cell efficacy in ovarian cancer.

NCT05372692.

Allogeneic chimeric antigen receptor T (CAR-T) therapy, also known as universal CAR-T (UCAR-T) therapy, offers broad applicability, high production efficiency, and reduced costs, enabling quicker access for patients. However, clinical application remains limited by challenges such as immune rejection, and issues with potency and durability.

We first screened a safe and effective anti-CD70 scFv to construct anti-CD70 CAR-T cells. Anti-CD70 UCAR-T cells were then generated by knocking out TRAC, B2M, and HLA-DRA. To address the limitations of UCAR-T therapy, we developed an 'all-in-one' self-activated and protective (SAP) module, integrated into the CAR scaffold. The SAP module consists of the CD47 extracellular domain, a mutant interleukin 7 receptor alpha (IL7Rα) transmembrane domain, and the IL7Rα intracellular domain, designed to protect UCAR-T cells from host immune attacks and enhance their survival.

SAP UCAR-T cells demonstrated significantly reduced immune rejection from the innate immune system, as evidenced by enhanced survival and functionality both in vitro and in vivo. The modified UCAR-T cells exhibited improved persistence, with no observed safety concerns. Furthermore, SAP UCAR-T cells maintained process stability during scale-up production, indicating the potential for large-scale manufacturing.

Our findings highlight the SAP module as a promising strategy for the preclinical development of anti-CD70 UCAR-T, paving the way for an 'off-the-shelf' cell therapy product.