{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T14:27:03Z","timestamp":1785421623697,"version":"3.56.0"},"reference-count":35,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T00:00:00Z","timestamp":1781827200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100014188","name":"Ministry of Science and ICT","doi-asserted-by":"publisher","award":["NRF-2017R1D1A1B03035014"],"award-info":[{"award-number":["NRF-2017R1D1A1B03035014"]}],"id":[{"id":"10.13039\/501100014188","id-type":"DOI","asserted-by":"publisher"}]},{"award":["NRF-2017R1D1A1B03035014"],"award-info":[{"award-number":["NRF-2017R1D1A1B03035014"]}],"id":[{"id":"https:\/\/ror.org\/01wpjm123","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Immune checkpoint inhibitors (ICIs) show promise in cancer but have limited efficacy in ovarian cancer. This study compared combinations of the PD-1\/PD-L1 inhibitor with anti-LAG-3, anti-TIM-3, or anti-CTLA-4 to identify the most effective regimen by assessing T-cell CD8\/CD4 ratios and cytokine production. T cells isolated from ovarian cancer tissues (mean 3.8 \u00d7 108 cells) were stimulated and treated with the PD-1\/PD-L1 inhibitor alone or combined with anti-LAG-3, anti-TIM-3, or anti-CTLA-4. Flow cytometry measured CD8\/CD4 expression; ELISAs quantified TNF-\u03b1, IL-6, and IFN-\u03b3. Anti-PD-1 monotherapy produced no significant change in CD8\/CD4 ratio (1.36 \u00b1 0.43 vs. 1.41 \u00b1 0.36) or cytokine levels. Combination therapy with PD-1\/PD-L1 inhibitor + anti-CTLA-4 induced the largest increase in CD8\/CD4 ratio (3.69 \u00b1 1.33, p &lt; 0.001) compared with PD-1\/PD-L1 inhibitor alone; increases were smaller for PD-1\/PD-L1 inhibitor + anti-LAG-3 (2.11 \u00b1 0.63, p = 0.009) and PD-1\/PD-L1 inhibitor + anti-TIM-3 (1.87 \u00b1 0.48, p = 0.026). TNF-\u03b1 rose significantly only with PD-1\/PD-L1 inhibitor + anti-CTLA-4 (106.69 \u00b1 45.42 pg\/mL, p = 0.008), not with PD-1\/PD-L1 inhibitor + anti-LAG-3 (72.46 \u00b1 31.79 pg\/mL, p = 0.231) or PD-1\/PD-L1 inhibitor + anti-TIM-3 (82.06 \u00b1 33.63 pg\/mL, p = 0.074). IFN-\u03b3 increase was greater with PD-1\/PD-L1 inhibitor + anti-CTLA-4 than with PD-1\/PD-L1 inhibitor + anti-LAG-3 (p = 0.026). In conclusion, dual PD-1\/PD-L1 and CTLA-4 blockade induced concomitant increases in T-cell CD8\/CD4 proportions and cytokine levels compared to monotherapy or alternative ICI pairings. These descriptive ex vivo observations offer preliminary evidence of altered immune profiles, highlighting this combination as a candidate for further functional validation.<\/jats:p>","DOI":"10.3390\/ijms27125567","type":"journal-article","created":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T03:09:17Z","timestamp":1782270557000},"page":"5567","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["CTLA-4 Blockade Combined with PD-1\/PD-L1 Inhibition Enhances Cytokine Production and T-Cell Activation in Ex Vivo Ovarian Cancer Cultures"],"prefix":"10.3390","volume":"27","author":[{"given":"Maitreyee","family":"Parulekar","sequence":"first","affiliation":[{"name":"Department of Obstetrics and Gynecology, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wook Ha","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miseon","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kidong","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2389-6757","authenticated-orcid":false,"given":"Jae Hong","family":"No","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1196-369X","authenticated-orcid":false,"given":"Yong Beom","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4312-966X","authenticated-orcid":false,"given":"Dong Hoon","family":"Suh","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Seoul National University Bundang Hospital, Seongnam 13620, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1016\/j.immuni.2004.07.017","article-title":"The immunobiology of cancer immunosurveillance and immunoediting","volume":"21","author":"Dunn","year":"2004","journal-title":"Immunity"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"795547","DOI":"10.3389\/fonc.2021.795547","article-title":"Immunotherapy in Ovarian Cancer: Thinking Beyond PD-1\/PD-L1","volume":"11","author":"Chardin","year":"2021","journal-title":"Front. 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Dermatol."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/27\/12\/5567\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T03:18:03Z","timestamp":1782271083000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/27\/12\/5567"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,19]]},"references-count":35,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2026,6]]}},"alternative-id":["ijms27125567"],"URL":"https:\/\/doi.org\/10.3390\/ijms27125567","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,19]]}}}