我们已经发现了一种被称为TheraVac疫苗的组合免疫疗法，可以治愈多个大型的老鼠肿瘤，但它未能治愈小鼠黑色素瘤。TheraVac包含一个免疫刺激的臂，其中包括TLR4激动剂（HMGN1 [N1]）和TLR7/8激动剂（R848），它们协同作用于激活肿瘤浸润性树突状细胞（DCs）并促进Th1免疫反应。第二臂使用免疫检查点阻滞，抗PDL-1，来减少肿瘤相关的免疫抑制作用。在本研究中，我们研究了TheraVac疫苗的一种辅助治疗，即IFN基因的刺激剂（STING）激动剂，环状鸟苷酸二磷酸腺苷（cGAMP），因为它们共同协同作用于激活DCs并产生更多的免疫刺激性IL-12p70和TNF-α细胞因子。DCS的协同激活和成熟取决于油罐结合激酶-1（TBK1）的活化。通过给予肿瘤内注射cGAMP和TheraVac来治疗三种不同的黑色素生成老鼠黑色素瘤（B16F1、M3和M4），可根除这些黑色素瘤的60-80%。TheraVac加cGAMP治疗的M3肿瘤的免疫谱显示，肿瘤中CD8+ CTLs和巨噬细胞增加。肿瘤中的CD4、CD8效应细胞和记忆T细胞也显著增加，并产生功能性的肿瘤特异性CTLs，这些CTLs定位于肿瘤引流淋巴结。结果是没有肿瘤的小鼠对同一种肿瘤的再次挑战有选择性的抵抗力，表明他们具有长期的肿瘤特异性保护性免疫力。总的来说，我们的发现对于临床试验具有重要意义，使用这些免疫治疗组合可以治愈生成黑色素的人体黑色素瘤，而无需外源性肿瘤抗原，在小鼠中也没有明显的毒性效应。

We have identified a combinational immunotherapy termed TheraVac vaccine (TheraVac) that can cure multiple large established mouse tumors, but it failed to cure melanoma in mice. TheraVac consists of an immunostimulating arm containing an agonist (HMGN1 [N1]) for TLR4 and an agonist (R848) for TLR7/8 that synergize to activate tumor-infiltrating dendritic cells (DCs) and promote Th1 immune responses. The second arm uses an immune checkpoint blockade, anti-PDL-1, to diminish tumor-associated immunosuppression. In this study, we investigated supplementation of TheraVac by a stimulator of IFN genes (STING) agonist, cyclic GMP-AMP (cGAMP), because together they synergize in activating DCs and produced more immunostimulating IL-12p70 and TNF-α cytokines. The synergistic activation and maturation of DCs is dependent on the activation of tank binding kinase-1 (TBK1). Treatment of three different melanin-producing mouse melanomas (B16F1, M3, and M4) with intratumoral delivery of cGAMP and TheraVac eradicated 60-80% of these melanomas. Immunoprofiling of M3 tumor treated with TheraVac plus cGAMP showed an increase in CD8+ CTLs and macrophages in the tumor. There was also a marked increase of CD4, CD8 effector and memory T cells and generation of functional tumor-specific CTLs in tumor-draining lymph nodes. The resultant tumor-free mice were selectively resistant to subsequent challenge with the same tumors, indicating long-term tumor-specific protective immunity. Overall, our findings have important implications for clinical trials with a combination of these immunotherapeutics to cure melanin-producing human melanomas, without the need for exogenous tumor Ags and no clear toxic effects in mice.