CD4 and neoplasm: In addition, the phototherapy of HA‐BP elicited ICD to mediate antitumor immunity by secreting damage‐associated molecular patterns (DAMPs), including surface‐exposed calreticulin (CRT), adenosine triphosphate (ATP), and high‐mobility group protein B1 (HMGB1), to promote prominent dendritic cell maturation and then induce the activation of specific effector T cells (such as CD4+/CD8+ T cells) to further eliminate tumor cells.