Toll-Like Receptor 7 Agonist Therapy with Imidazoquinoline Enhances Cancer Cell Death and Increases Lymphocytic Infiltration and Proinflammatory Cytokine Production in Established Tumors of a Renal Cell Carcinoma Mouse Model
Figure 6
3M011 increases T-cell lymphocytic infiltration in RCC tumors. CD3 immunohistochemical staining of T-cell lymphocytes in RENCA RCC xenografts following treatment with placebo or 3M011 imidazoquinoline. (a) Representative RCC tumor from a placebo-treated mouse with mild T-cell lymphocyte collection at the tumor surface but little intratumoral penetration (200x magnification). (b) Center of tumor from (a) with infrequent T-cell lymphocytes (200x magnification). (c) Example of a placebo-treated tumor with moderate T-cell concentration at the tumor periphery but still little central tumor infiltration (100x magnification). (d), (e) Representative 3M011-treated tumors with large T-cell aggregates at the tumor edge (100x and 200x magnification, resp.); the bottom aspect of (d) represents necrotic tumor. Note the effective intratumoral penetration in (e). (f) Representative 3M011-treated tumor center showing diffuse infiltration of CD3-positive T-cell lymphocytes (200x magnification). (g), (h) Tumor capsular CD3 staining (i) and intratumoral CD3 staining (j) comparison in mice treated with placebo versus 3M011 on day 0 and day 7. *, **, ***, and †.
