N-glycosylation is required for human CD2 immunoadhesion functions

• Published in: The Journal of biological chemistry 1992-11, Vol.267 (31), p.22428-22434
• Main Authors: RECNY, M. A, LUTHER, M. A, REINHOLD, V. N, REINHERZ, E. L, KNOPPERS, M. H, NEIDHARDT, E. A, KHANDEKAR, S. S, CONCINO, M. F, SCHIMKE, P. A, FRANCIS, M. A, MOEBIUS, U, REINHOLD, B. B
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Antigens, CD - metabolism; Antigens, Differentiation, T-Lymphocyte - chemistry; Antigens, Differentiation, T-Lymphocyte - metabolism; Base Sequence; Biological and medical sciences; CD2 Antigens; CD58 Antigens; Cell Adhesion Molecules - chemistry; Cell interactions, adhesion; Fundamental and applied biological sciences. Psychology; Glycosylation; Humans; Mass Spectrometry; Membrane Glycoproteins - chemistry; Membrane Glycoproteins - metabolism; Molecular and cellular biology; Molecular Sequence Data; Mutagenesis, Site-Directed; Oligodeoxyribonucleotides - chemistry; Receptors, Immunologic - chemistry; Receptors, Immunologic - metabolism; Rosette Formation; Structure-Activity Relationship
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)41689-4

The T-lymphocyte glycoprotein receptor, CD2, mediates cell-cell adhesion by binding to the surface molecule CD58 (LFA-3) on many cell types including antigen presenting cells. Two domains comprise the CD2 extracellular segment, with all adhesion functions localized to the amino-terminal domain that contains a single N-glycosylation site at Asn65. We have defined an important role for the N-linked glycans attached to Asn65 of this domain in mediating CD2-CD58 interactions and also characterize its N-glycotype structure. Analysis of deglycosylated soluble recombinant CD2 as well as a mutant transmembrane CD2 molecule containing a single Asn65-Gln65 substitution demonstrates that neither deglycosylated CD2 nor the mutant CD2 transmembrane receptor binds CD58 or monoclonal antibodies directed at native CD2 adhesion domain epitopes. Electrospray ionization-mass spectrometry demonstrates that high mannose oligosaccharides ((Man)nGlcNAc2, n = 5-9) are the only N-glycotypes occupying Asn65 when soluble CD2 is expressed in Chinese hamster ovary cells. Based on a model of human CD2 secondary structure, we propose that N-glycosylation is required for stabilizing domain 1 in the human receptor. Thus, N-glycosylation is essential for human CD2 adhesion functions.