Due to its size, shape, and inherent expression of pathogen-associated molecular patterns and invasion-assistant adhesion proteins, Burkholderia pseudomallei can easily attach to, and then be internalized by, dendritic cells (DCs), leading to more efficient antigen cross-presentation if modified as carrier. Herein, we engineered Burkholderia pseudomallei as a porous/hollow carrier (SB) for loading tumor lysates (L) and adjuvant CpG (C) to be used as a tumor vaccine (SB-LC). We found that the adhesion proteins of Burkholderia pseudomallei promote internalization of the SB-LC vaccine by DCs, and result in enhanced DC maturation and antigen cross-presentation. SB-LC induces robust cellular and humoral antitumor responses that synergistically inhibit tumor growth with minimal adverse side effects in several tumor models. Moreover, SB-LC vaccination reverses the immunosuppressive tumor microenvironment, apparently as a result of CD8⁺-induced tumor ferroptosis. Thus, SB-LC is a potential model tumor vaccine for translating into a clinically viable treatment option.

由于其大小、形状和病原体相关分子模式和侵袭辅助粘附蛋白的固有表达，假鼻疽伯克霍尔德菌可以很容易地附着在树突细胞 (DC) 上，然后被树突细胞 (DC) 内化，从而导致更有效的抗原交叉呈递如果修改为载体。在此，我们将假鼻疽伯克霍尔德菌设计为多孔/中空载体 (SB)，用于装载肿瘤裂解物 (L) 和佐剂 CpG (C)，用作肿瘤疫苗 (SB-LC)。我们发现假鼻疽伯克霍尔德菌的粘附蛋白促进内化SB-LC 疫苗被 DC 降解，并导致 DC 成熟和抗原交叉呈递增强。SB-LC 诱导强大的细胞和体液抗肿瘤反应，在几种肿瘤模型中协同抑制肿瘤生长且副作用最小。此外，SB-LC 疫苗接种逆转了免疫抑制性肿瘤微环境，这显然是 CD8 ⁺诱导的肿瘤铁死亡的结果。因此，SB-LC 是一种潜在的模型肿瘤疫苗，可转化为临床上可行的治疗方案。