IL2 and tuberculosis: Among the BCG strains that were compared in infants, BCG-Japan appears to induce Th1 cytokines (IFN-γ, TNF, IL-2) and CD4+ T cells better than BCG-Danish and -Russia.58, 61 A retrospective analysis of cohorts in Kazakhstan found that BCG-Japan was also more effective in reducing the risk for TB in infants than BCG-Russia or BCG-Serbia.70