Linked Life Data

8609400

Source:http://linkedlifedata.com/resource/pubmed/id/8609400

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1996-5-29
pubmed:abstractText
To generate Ab responses to most protein Ags, B cells must first degrade proteins in endocytic compartments and then display antigenic peptides bound to MHC class II molecules. T helper lymphocytes recognize these complexes and stimulate the B cell to synthesize Ab. Although Ab play a key role in host defense against bacteria, it is believed that B cells are incapable of internalizing particulate Ags. However, we find that B lymphoblastoid cell lines and LPS-activated B lymphocytes can present particulate Ag up to 10(5)-fold more efficiently compared with soluble Ag. Moreover, particulate Ags are presented efficiently by unstimulated B cells when they bind to surface Ig. In comparison to B cells, macrophages in general presented particulate Ags 10- to 1000-fold more efficiently and could also present Ag from particles of a much wider range of sizes. We document by ultrastructural and immunofluorescence analysis that B lymphoblastoid cell lines bind and internalize these particles. The internalization and presentation of the particulate Ag is inhibited by cytochalasin B. In contrast, a similar morphologic analysis of normal lymphocytes demonstrated that while Ag beads are bound to the cell surface, they are internalized only rarely. These results suggest there may be both surface and intracellular pathways for the presentation of particulate Ags by B cells. Interestingly, for both macrophages and B cells, the epitopes generated from particulate and soluble Ags were not identical quantitatively or qualitatively, indicating that there are differences in how these forms of Ag are processed and presented.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
156
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2809-18
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Analysis of MHC class II presentation of particulate antigens of B lymphocytes.
pubmed:affiliation
Division of Lymphocyte Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't