Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1993-10-14
pubmed:abstractText
The T lymphocyte glycoprotein CD2 appears to have an important role in human T cell development and activation. A novel anti-CD2 monoclonal antibody, designed UMCD2, was shown to block E rosetting, and therefore was defined as recognizing the Tll1 ligand-binding epitope. Binding of UMCD2 to T cells and thymocytes was blocked by several, but not all, anti-Tll1 antibodies, suggesting that the Tll1 epitope consists of more than one subepitope. In functional studies, the combination of UMCD2 plus anti-Tll3 was mitogenic for T cells; in some individuals, the level of activation was as high as that seen for the combination of anti-Tll2 plus anti-Tll3. However, when UMCD2 was added to other stimuli mitogenic for T lymphocytes, such as IL-2 or anti-CD3-Sepharose, it inhibited T cell responses. Although the combination of UMCD2 and anti-Tll3 induced an increase in cytoplasmic free calcium, the inhibitory activities of UMCD2 were not accompanied by effects on calcium fluxes. A panel of previously characterized CD2 mutants was then analyzed for binding of UMCD2 and other anti-CD2 monoclonals. Surprisingly, UMCD2 bound to all mutants tested, although the other anti-CD2 antibodies with specificity for the ligand-binding region of CD2 each failed to bind to one or more mutants. These data suggest that binding of antibody to a particular CD2 epitope can have opposite effects on the state of T cell activation, depending on the costimulus. Moreover, inhibitory effects mediated through CD2 may use a signaling mechanism distinct from that used in CD2 pathway activation. Of particular interest, the portion of the CD2 ligand-binding region recognized by UMCD2 is distinct from areas of the CD2 molecule that have previously been studied.
pubmed:grant
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0008-8749
pubmed:author
pubmed:issnType
Print
pubmed:volume
150
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
235-46
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
An anti-CD2 monoclonal antibody that both inhibits and stimulates T cell activation recognizes a subregion of CD2 distinct from known ligand-binding sites.
pubmed:affiliation
Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor 48109-0358.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't