Differential up-regulation of the B7-1 and B7-2 costimulatory molecules after Ig receptor engagement by antigen

Deborah J. Lenschow, Anne I. Sperling, Michael P. Cooke, Gordon Freeman, Lesley Rhee, Donna C. Decker, Gary Gray, Lee M. Nadler, Christopher C. Goodnow, Jeffrey A. Bluestone

Research output: Contribution to journalArticlepeer-review

265 Scopus citations


Ag-pulsed B cells are potent APCs, in part, because of the ability of the Ig receptor to mediate rapid and specific Ag uptake. However, it is also known that full T cell activation requires signals delivered by costimulatory molecules, which naive B cells seem to lack. This study examines the effect Ig receptor engagement has on the expression and function of a new CD28 counter-receptor, B7-2. Unlike B7-1 (B7), B7-2 was rapidly induced on the cell surface of B cells after engagement of the Ig receptor by either anti- Ig mAbs or hen egg lysozyme (HEL) on normal and HEL-specific B cell receptor transgenic B cells, respectively. Furthermore, B7-2 expression was up- regulated on tolerant B cells isolated from HEL/anti-HEL double transgenic mice after Ag stimulation, although at lower levels than on nontolerant transgenic B cells. No significant cell surface levels of B7-1(B7) were observed under these conditions. Finally, the B7-2 molecules induced by Ig cross-linking costimulated T cell proliferation in a CD28-dependent manner, independent of B7-1(B7) expression. Thus, the effectiveness of Ag-specific B cells as APCs depends on both their enhanced Ag uptake, mediated by the B cell receptor, and immediate up-regulation of a potent costimulatory molecule, B7-2.

Original languageEnglish
Pages (from-to)1990-1997
Number of pages8
JournalJournal of Immunology
Issue number5
StatePublished - Sep 1 1994


Dive into the research topics of 'Differential up-regulation of the B7-1 and B7-2 costimulatory molecules after Ig receptor engagement by antigen'. Together they form a unique fingerprint.

Cite this