Constitutive STAT3 Signaling, in Comparison with STAT5, Enhances CAR T-Cell Efficacy, and Lowers Systemic Toxicity

Scientists engineered CAR T cells to express constitutively active mutants of STAT3 and STAT5 to investigate their individual functions. Co-expression of constitutive active mutants (ca) of STAT3 and caSTAT5 markedly enhance the long-term proliferative capacity of CAR T cells, even in the absence of antigen stimulation or cytokine supplementation.