{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,7,30]],"date-time":"2025-07-30T15:58:28Z","timestamp":1753891108577,"version":"3.41.2"},"reference-count":35,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,4,17]],"date-time":"2025-04-17T00:00:00Z","timestamp":1744848000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["R56 AI139476"],"award-info":[{"award-number":["R56 AI139476"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000057","name":"National Institute of General Medical Sciences","doi-asserted-by":"publisher","award":["T32 GM008336"],"award-info":[{"award-number":["T32 GM008336"]}],"id":[{"id":"10.13039\/100000057","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:p>Macrophages and dendritic cells acquire bacteria and cytosolic content from other cells without killing the donor cell through a trogocytosis-associated process termed merocytophagy. While characteristics of this behavior have been partially identified, the mechanism and potential contribution to the response to infection are unclear. Here, we reveal that a wide range of distinct species of bacteria stimulate enhanced merocytophagy in macrophages through pattern recognition receptor (PRR). Further, we found that cell-to-cell transfer in response to <jats:italic>Francisella tularensis<\/jats:italic> infection occurs in a predominantly MyD88-independent manner, relying on spleen tyrosine kinase (Syk) activity. Syk signaling during this response also results in increased surface expression of cell-to-cell adhesion proteins integrin \u03b14, integrin \u03b21, ICAM-1 and CD44 at the site of merocytophagy transfer, and depleting these surface molecules impairs merocytophagic cell-to-cell transfer. Altogether, our data demonstrate that merocytophagy is a host response to infection facilitated by tight cell-to-cell binding which molecularly resembles an immunological synapse between macrophages.<\/jats:p>","DOI":"10.3389\/fimmu.2025.1565250","type":"journal-article","created":{"date-parts":[[2025,4,17]],"date-time":"2025-04-17T05:24:34Z","timestamp":1744867474000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Merocytophagy is an integrin-stabilized macrophage response to microbes reliant on Syk signaling"],"prefix":"10.3389","volume":"16","author":[{"given":"Kelly N.","family":"Deobald","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shaun P.","family":"Steele","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sedelia 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