CEA-related cell adhesion molecule 1 (CEACAM1) is a member of the carcinoembryonic antigen (CEA) family that is expressed on activated T lymphocytes. Previous studies have reported both costimulatory and coinhibitory roles for this glycoprotein in T cell activation and effector functions. We have used a Ceacam1-/- mouse model to further explore this paradox. We demonstrate that CEACAM1 is not involved in T cell development or in migration of these lymphocytes to peripheral lymphoid organs. In vitro, CEACAM1 was observed to play an inhibitory role on T lymphocytes as it limits T cell proliferation in response to T cell receptor-specific antibodies and mitogens. In vivo proliferative responses were not affected by the absence of CEACAM1 upon administration of antigen emulsified with adjuvant, yet cytokine secretion revealed that CEACAM1 may be involved in the control of Th1-type responses. A new transgenic model for CEACAM1 overexpression on T lymphocytes was generated and further experimentation will be necessary to confirm the above observations. Hence, CEACAM1 is playing an inhibitory role on T cell surfaces, most likely by intracellular signal transmission through its ITIM motifs.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.81247 |
| Date | January 2003 |
| Creators | Farrah, Jennifer |
| Contributors | Beauchemin, Nicole (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Biochemistry.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 002031486, proquestno: AAIMQ98835, Theses scanned by UMI/ProQuest. |
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