Metastasis enables immunogenicity through migrasome-mediated antigen release.

Metastasis-associated migrasomes are enriched in tumor antigens and promote CD8+ T cell responses that constrain metastatic progression.

• Why it matters: Understanding how antigen release is regulated during metastasis is crucial for developing effective immunotherapies, as this process influences immune activation against tumors.
• What they did: The study examined circulating tumor cells during vascular migration and found they produce migrasomes containing tumor-associated antigens, which are captured by antigen-presenting cells and cross-presented to activate T cells; genetic inhibition of migrasome formation increased metastasis, while administering purified migrasomes restored immune suppression.
• The result: Findings suggest metastasis can enhance tumor immunogenicity via migrasome-mediated antigen release, establishing migrasomes as a potent platform for endogenous tumor antigen delivery that may inform new immunotherapeutic strategies.