title: CD43 is a ligand for E-selectin on CLA+ human T cells.
abstract: The recruitment of memory T cells from blood into tissues is a central element of immune surveillance and adaptive immune responses and a key feature of chronic cutaneous inflammatory diseases such as psoriasis and atopic dermatitis. Human memory T cells that infiltrate skin express the carbohydrate epitope cutaneous lymphocyte-associated antigen (CLA). Expression of the CLA epitope on T cells has been described on P-selectin glycoprotein ligand-1 (PSGL-1) and associated with the acquisition of both E-selectin and P-selectin ligand functions. In this report, we show that CD43, a sialomucin expressed constitutively on T cells, can also be decorated with the CLA epitope and serve as an E-selectin ligand. CLA expressed on CD43 was found exclusively on the high-molecular-weight (125 kDa) glycoform bearing core-2-branched O-linked glycans. CLA+ CD43 purified from human T cells supported tethering and rolling in shear flow via E-selectin but did not support binding of P-selectin. The identification and characterization of CD43 as a T-cell E-selectin ligand distinct from PSGL-1 expands the role of CD43 in the regulation of T-cell trafficking and provides new targets for the modulation of immune functions in skin.
authors.affiliation: Department of Dermatology, Brigham and Women's Hospital, Harvard Institutes of Medicine, 77 Ave Louis Pasteur, Boston, MA 02115, USA. rfuhlbrigge@partners.org
authors.forename: Robert C
authors.initials: RC
authors.lastname: Fuhlbrigge
authors.forename: Sandra L
authors.initials: SL
authors.lastname: King
authors.forename: Robert
authors.initials: R
authors.lastname: Sackstein
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Kupper
mesh_terms: D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D000951:Antigens, Neoplasm / Q000502:physiology; D019040:E-Selectin / Q000502:physiology*; D006801:Humans; D051917:Leukosialin / Q000502:physiology*; D008562:Membrane Glycoproteins / Q000276:immunology / Q000302:isolation & purification / Q000502:physiology*; D009000:Monocytes / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D000951:Antigens, Neoplasm; C063419:CTAGE1 protein, human; D019040:E-Selectin; D051917:Leukosialin; D008562:Membrane Glycoproteins; C084882:P-selectin ligand protein