利用 SARS-CoV-2 免疫通过瘤内疫苗接种和过继转移促进抗肿瘤反应

To test this concept, we evaluated the therapeutic efficacy of intratumoral SARS-CoV-2 vaccination in the B16F10 murine melanoma model using two SARS-CoV-2 vaccine platforms: pVAX-SARS-S, a DNA vaccine encoding the spike protein S1 subunit and rAd-SARS2-S1/CD40L, a recombinant adenovirus expressing a secreted S1-CD40L fusion protein. Tumor-bearing C57BL/6 mice were treated intratumorally with either vaccine in the presence or absence of prior immunization, which had been established six months earlier to mimic pre-existing antiviral immunity.

Intratumoral vaccination with pVAX-SARS-S significantly reduced tumor burden and prolonged survival in both naïve and pre-immunized mice. Its antitumor protection could be adoptively transferred via splenocytes, indicating the involvement of systemic adaptive immunity in mediating tumor rejection. The rAd-SARS2-S1/CD40L platform conferred modest tumor control. While both vaccines were effective, the DNA platform demonstrated superior efficacy. DISCUSSION: Together, these findings provide proof-of-concept that intratumoral administration of SARS-CoV-2 vaccines can promote antitumor effects through local immune activation in the context of pre-existing antiviral immunity. This strategy may offer a translatable approach for enhancing intratumoral immunotherapy in the post-pandemic era.