Format

Send to

Choose Destination
Int Immunol. 2002 Mar;14(3):309-18.

Overexpression of rab7 enhances the kinetics of antigen processing and presentation with MHC class II molecules in B cells.

Author information

1
Department of Immunology, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.

Abstract

rab7 is an intracellular GTPase involved in early to late endosome fusion. By overexpressing rab7 in a B lymphoma we show that the rate of antigen presentation with MHC class II molecules is increased for four different peptide-MHC combinations, under conditions where levels of other components of the antigen-processing pathway remained constant. Resting B cells were shown to express significantly lower levels of rab7 when compared to adherent macrophages or to 'immature' or 'mature' dendritic cells. rab7 expression was up-regulated by stimulation of B cells with lipopolysaccharide or CD40 ligand. Other components of the endocytic pathway were also up-regulated in activated B cells, suggesting that B cell activation leads to a general enlargement of the endocytic compartment, correlating with the increased ability of activated B cells to process antigen. Taken together, our results suggest that rab7 levels regulate the rate of antigen presentation in B cells, and that rab7 and late endocytic compartments are important in MHC class II-restricted antigen presentation in B cells.

PMID:
11867567
DOI:
10.1093/intimm/14.3.309
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Silverchair Information Systems
Loading ...
Support Center