CD4 and melanoma: After SLTBI treatment in 57BL/6 mice with melanoma model, both the cell counts and the frequencies of total T cells (CD3+) and CD4+ and CD8+ T cells from the spleen were significantly decreased within 3 to 5 days, and CD3+CD4+T cell restoration started from day 8 and returned to normal levels 10 days after exposure, which showed that the reconstitution of CD4+ T-helper cells was delayed after SLTBI.