On single nasal immunization of mice with killed-bacillus calmette–guerin (BCG) plus a mutant Escherichia coli enterotoxin, delayed-type hypersensitivity was induced and BCG-infection decreased. Spleen cells, particularly CD4 + T cells among them produced IL-2, IFNγ and TNFα in response to the killed-BCG or purified protein derivatives. CD8 + T cells including cytotoxic T lymphocytes produced IFNγ and TNFα. However, both types of T cells reacted a little to Ag85B.The mutant induces cellular immunity to nasal killed-BCG vaccine and decreases BCG-infection. CD4 + and CD8 + T cells produce cytokines effective for tuberculosis. Although killed-BCG loses some antigens like Ag85B, nasal killed-BCG plus the mutant is useful for tuberculosis.