Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
DIFFERENTIAL RECOGNITION BY CD28 OF ITS COGNATE COUNTER RECEPTORS CD80 (B7.1) AND B70 (B7.2) - ANALYSIS BY SITE-DIRECTED MUTAGENESIS
Autore:
TRUNEH A; REDDY M; RYAN P; LYN SD; EICHMAN C; COUEZ D; HURLE MR; SEKALY RP; OLIVE D; SWEET R;
Indirizzi:
SMITHKLINE BEECHAM PHARMACEUT,MOLEC IMMUNOL KING OF PRUSSIA PA 19406 SMITHKLINE BEECHAM PHARMACEUT,MACROMOLEC SCI KING OF PRUSSIA PA 19406 IRCM MONTREAL PQ CANADA INSERM U119 MARSEILLE FRANCE
Titolo Testata:
Molecular immunology
fascicolo: 3, volume: 33, anno: 1996,
pagine: 321 - 334
SICI:
0161-5890(1996)33:3<321:DRBCOI>2.0.ZU;2-0
Fonte:
ISI
Lingua:
ENG
Soggetto:
T-CELL ACTIVATION; IMMUNOGLOBULIN SUPERFAMILY; MOLECULAR-CLONING; EXPRESSION SYSTEM; MURINE HOMOLOG; CTLA-4; ANTIGEN; CDNA; IDENTIFICATION; PROLIFERATION;
Keywords:
CD28; CTLA-4; CD80; CD86; B7.1; B7.2; B70; IGSF; IG-FOLD; SITE DIRECTED MUTAGENESIS; RECEPTOR RECOGNITION; EPITOPE MAPPING;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Science Citation Index Expanded
Citazioni:
38
Recensione:
Indirizzi per estratti:
Citazione:
A. Truneh et al., "DIFFERENTIAL RECOGNITION BY CD28 OF ITS COGNATE COUNTER RECEPTORS CD80 (B7.1) AND B70 (B7.2) - ANALYSIS BY SITE-DIRECTED MUTAGENESIS", Molecular immunology, 33(3), 1996, pp. 321-334

Abstract

CD28, which is a member of the immunoglobulin superfamily of molecules (IgSF), is a homodimer of two polypetides containing a single V-likedomain with short transmembrane and cytoplasmic regions. It serves asa co-signalling molecule for T cell activation through binding to itscognate counter-receptors CD80 and B70, expressed on antigen presenting cells. In the current study, we investigated the regions of CD28 which are involved in its interactions with CD80 and B70, using site directed mutagenesis, CD28 mAb epitope mapping, receptor based adhesion assays and direct binding of Ig-fusion proteins to cell surface receptors. Truncation or substitution of a stretch of a proline rich ''hallmark'' sequence, ''MYPPPY'', abrogates binding to CD80 or B70, while retaining CD28 mAb epitopes and cell surface expression. On an Ig-fold model of the CD28 V-domain, this fully conserved motif localizes to a CDR3-like region. Mutations introduced into other loops, including the CDR1-like and CDR2-like regions, had very little effect on CD80 or B70 binding. Mutations introduced within the predicted beta-strand regionscaused loss of receptor expression. Conservative substitution of boththe flanking tyrosine residues within the ''MYPPPY'' motif with phenylalanine, caused loss of binding to B70 but not to CD80. These resultsshow that, although the same overall region on CD28 may be involved in the interactions with CD80 and B70, subtle but important differencesdistinguish recognition by the two molecules. These findings, along with previous observations on the differential pattern of expression and tissue distribution of CD80 and B70, support the contention that these molecules play distinct roles in the regulation of immune responsesin vivo. Copyright (C) 1996 Elsevier Science Ltd.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 21/09/20 alle ore 19:19:08