CD4 and mesothelioma: Furthermore, in a mouse mesothelioma model, CD4+ TEXprog cells are reported to be transcriptionally similar to CD8+ TEXprog cells and increase during PD‐1/PD‐L1 blockade.[122] Notably, a subset of non‐cytotoxic TFH cells also exhibit a stem‐like progenitor exhaustion phenotype.[41] They can differentiate into TFH‐like cytotoxic CD4+ T cells, which bear a terminally differentiated exhaustion phenotype.