CD4 and neoplasm: Not surprisingly, the “EcN-cypate + HBO + laser” group exhibited the highest proportions of CD8+ and CD4+ T cells (26.4% and 64.1%, respectively), which were much higher than those of the control group (6.0% CD8+ T cells and 17.6% CD4+ T cells) (Fig. 8j), demonstrating that the HBO-combined PTT can substantially increase the levels of cytotoxic and helper T cells, which may help to realize effective tumor immunotherapy.