In the Lewis lung carcinoma model, vaccination efficiently increases the CD3+CD4+ and CD3+CD8+ T cell populations in the spleens and CD3+CD8+, CD3−CD8+, and CD11b+CD80+ cell populations in the tumors, suggesting the alteration of the tumor microenvironment from cold to hot tumors. Here, CD80 is linked to Carcinoma, Lewis Lung.