CD4 and lymphoma: Moreover, Ding ZC et al. demonstrated that co-expression of a constitutively active form of signal transducer and activator of transcription 5 (CA-STAT5) and a CD19 CAR enabled extensive epigenetic and chromatin remodeling in tumor-specific CD4+ cells, which diverted the fate of CD4+ cells from exhaustion to polyfunctionality and gave rise to tumor-tropic, anti-tumor T cells capable of vigorously accumulating within sites of lymphoma and eliciting anti-tumor CD8+ T-cell responses with a high cure rate in mice with advanced lymphoma