{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T06:00:43Z","timestamp":1785477643745,"version":"3.56.0"},"reference-count":41,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T00:00:00Z","timestamp":1785456000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:p>\n                    Immune checkpoint inhibitors have significantly improved therapeutic outcomes in advanced melanoma; however, their clinical efficacy is greatly limited by low overall response rates and the primary or acquired resistance. Here, we developed a SpyCatcher-engineered bacterial outer membrane vesicle (OMV) platform for the co-delivery of a PD-1\/PD-L1 inhibitor, the D-PPA1 peptide, and the epigenetic regulator zebularine (Zeb). The resulting co-delivery system, OMV@PPA\/Zeb, effectively blocked PD-1\/PD-L1 interactions and markedly upregulated melanoma-associated antigens, including CD146 and TRP1, in melanoma cells. In a subcutaneous melanoma mouse model, OMV@PPA\/Zeb substantially suppressed tumor growth without noticeable systemic toxicity. Moreover, OMV@PPA\/Zeb significantly promoted the infiltration and activation of CD8\n                    <jats:sup>+<\/jats:sup>\n                    T cells while reducing regulatory T cells (Tregs) within the tumor microenvironment. The potent antitumor immune response elicited by this platform contributed to its enhanced therapeutic efficacy against melanoma. Overall, this study provides a modular OMV-based strategy for combination immunotherapy in advanced tumors.\n                  <\/jats:p>","DOI":"10.3389\/fimmu.2026.1915499","type":"journal-article","created":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T05:38:37Z","timestamp":1785476317000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Modular engineered outer membrane vesicles for synergistic cancer immunotherapy via PD-L1 blockade and epigenetic reprogramming"],"prefix":"10.3389","volume":"17","author":[{"given":"Longxue","family":"Guan","sequence":"first","affiliation":[{"name":"Department of Dermatology, The Affiliated Wenling Hospital of Taizhou University (The First People\u2019s Hospital of Wenling), School of Medicine, Taizhou University","place":["Taizhou, China"]},{"name":"College of Medical Technology, Beihua University","place":["Jilin, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qinxiao","family":"Sun","sequence":"additional","affiliation":[{"name":"College of Medical Technology, Beihua University","place":["Jilin, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dandan","family":"Liang","sequence":"additional","affiliation":[{"name":"College of Medical Technology, Beihua University","place":["Jilin, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhimin","family":"Li","sequence":"additional","affiliation":[{"name":"College of Medical Technology, Beihua University","place":["Jilin, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shiqi","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Medical Technology, Beihua University","place":["Jilin, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laili","family":"Huang","sequence":"additional","affiliation":[{"name":"College of Medical Technology, Beihua University","place":["Jilin, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xingang","family":"Guan","sequence":"additional","affiliation":[{"name":"Department of Dermatology, The Affiliated Wenling Hospital of Taizhou University (The First People\u2019s Hospital of Wenling), School of Medicine, Taizhou University","place":["Taizhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hongxia","family":"Feng","sequence":"additional","affiliation":[{"name":"Department of Dermatology, The Affiliated Wenling Hospital of Taizhou University (The First People\u2019s Hospital of Wenling), School of Medicine, Taizhou University","place":["Taizhou, 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