CD4 and prostate cancer: For instance, research involving prostate cancer patients has reported alterations in immune parameters following carbon-ion irradiation, showing that overall frequencies of major immune cell types (CD3+, CD4+, CD8+ T cells, NK cells) remained unchanged, and there was an increase in the CD4/CD8 ratio, lymphocyte proliferation, and T-cell functionality, along with a reduction in B cells, offering insights into the complex interactions between particle therapy and the immune system (13).