CD4 and neoplasm: We examined whether the TLR9 ligand, TLR9 agonist could activate TLR9-expressing cells in vivo and analyzed the number and phenotype of splenic CD4+ T helper cells, CD8+ T cells, B cells, pDCs and NKDCs in tumor-bearing mice, 24 hours after TLR9 agonist administration (10 mg/kg body weight, s.c).