A soluble bi-specific fusion protein for the improved expansion of human CD8+ CAR-T cells

The article describes the development of a novel soluble protein T-CEP (T cell expansion protein) designed to activate and expand CAR-T cells used in cancer immunotherapy. The research team compared T-CEP with existing commercial activators (Dynabeads and TransAct) during expansion of T cells transduced with CD19 or IL-13 CAR lentiviral vectors. Results demonstrated that T-CEP achieved comparable transduction efficiency to commercial reagents and significantly promoted CD8+ T cell expansion with higher CD27+ phenotype proportion and lower CD4:CD8 ratio. CAR-T cells expanded using T-CEP exhibited equivalent cytotoxic function to cells activated with commercial reagents but with lower inflammatory cytokine secretion. The main advantage of T-CEP is that it does not require removal from culture media during CAR-T manufacturing, which simplifies the production process.