{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T14:56:46Z","timestamp":1781103406024,"version":"3.54.1"},"reference-count":0,"publisher":"National Academy of Sciences","issue":"1","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[1981,1]]},"abstract":"<jats:p>Three criteria have been used to distinguish among different systems of embryonic cell adhesion: dependence on Ca2+, involvement of particular cell-surface molecules, and binding specificity. The characterization of the adhesion with respect to cell-surface molecules was carried out by using specific antibodies against the neural and liver cell adhesion molecules (N-CAM and L-CAM) and antibodies raised against retinal cells prepared by limited trypsinization in the presence of Ca2+ (called \"T\/Ca cells\"). Aggregation of cells prepared from retina or brain without Ca2+ did not require Ca2+ and was inhibited by anti-(N-CAM) antibodies but not by anti-(L-CAM) or anti-T\/Ca cell antibodies. In contrast, cells obtained from the same tissues in the presence of Ca2+ did require Ca2+ to aggregate. This aggregation was inhibited by anti-T\/Ca cell antibodies but not by anti-(N-CAM) or anti-(L-CAM) antibodies. Hepatocyte aggregation also required Ca2+ and was inhibited only by anti-(L-CAM) antibodies. These results define three antigenically distinct cell adhesion systems in the embryo and raise the possibility that additional systems will be found. The neural Ca2+-independent system displayed a limited tissue specificity, mediating binding to neural but not liver cells. In contrast, the Ca2+-dependent systems of both neural and liver cells caused binding to all cell types tested. The Ca2+-dependent system was most active in retinal cells from 6-7 day embryos, whereas the Ca2+-independent system was most active at later times during development. In addition, treatments that inhibited the Ca2+-independent or Ca2+-dependent systems had very different effects on the fasciculation of neurites from dorsal root ganglia. All of the results suggest that Ca2+-independent and Ca2+-dependent adhesion systems play different functional roles during embryogenesis.<\/jats:p>","DOI":"10.1073\/pnas.78.1.387","type":"journal-article","created":{"date-parts":[[2006,5,31]],"date-time":"2006-05-31T04:27:26Z","timestamp":1149049646000},"page":"387-391","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":80,"title":["Distinct calcium-independent and calcium-dependent adhesion systems of chicken embryo cells."],"prefix":"10.1073","volume":"78","author":[{"given":"R","family":"Brackenbury","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"U","family":"Rutishauser","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G M","family":"Edelman","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[1981,1]]},"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.78.1.387","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T11:34:47Z","timestamp":1649849687000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/full\/10.1073\/pnas.78.1.387"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1981,1]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1981,1]]}},"alternative-id":["10.1073\/pnas.78.1.387"],"URL":"https:\/\/doi.org\/10.1073\/pnas.78.1.387","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[1981,1]]},"assertion":[{"value":"1981-01-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}