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Updated: Aug 8, 2026

Purification of the Dendritic Filopodia-rich Fraction
Published on: May 2, 2019
The neuronal glycoprotein telencephalin is a cellular ligand for the CD11a/CD18 leukocyte integrin
L Tian1, Y Yoshihara, T Mizuno
1Department of Biosciences, Division of Biochemistry, University of Helsinki, Finland.
Abstract:
Many leukocyte functions depend on interactions between the leukocyte-specific beta2 integrins CD11/CD18 and their ligands, the intercellular adhesion molecules (ICAMs). Telencephalin (TLN) is a novel member of the Ig superfamily expressed in the central nervous system. The NH2-terminal five Ig-like domains of TLN show the highest homology with the Ig domains of ICAM-1, ICAM-2, ICAM-3, and LW (ICAM-4), the known cellular ligands for CD11a/CD18. Here, we demonstrate that TLN interacts with CD11a/CD18. Peripheral blood T cells, Jurkat T cells, and B lymphoblastoid cells bound to immunopurified recombinant human TLN proteins. This adhesion was through CD11a/CD18 and was significantly inhibited by an Ab to CD11a/CD18. Reciprocally, TLN-transfected L cells also bound to purified CD11a/CD18. Recombinant TLN proteins comprising either the first five Ig domains (TLN(1-5)) or the entire extracellular portion (TLN(1-9)) showed binding to CD11a/CD18. We conclude that TLN is a novel neuronal cell adhesion molecule that may be important in integrin-mediated cell-cell interactions in the central nervous system, and that the CD11a/CD18-dependent recognition site of human TLN is located within the NH2-terminal five domains of this molecule.
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