Expression of HSP70, CD4-positive and CD8-positive T cells in Lewis lung cancer. (A) Without hyperthermia, staining for HSP70, CD4, and CD8 was negative. (B-D) However, following hyperthermia, HSP70, CD4, and CD8 were strongly expressed in the viable cells around the necrotic area (magnification, ×200). HSP, heat-shock protein; CD, cluster of differentiation.