Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1994-8-9
pubmed:abstractText
CD4 is a T lymphocyte receptor for major histocompatibility complex class II antigens. It is referred to as coreceptor because it synergizes with the T cell receptor for antigen when both receptors become engaged simultaneously. We show here in mice that when engaged by antibody independently of the T cell antigen receptor, CD4 induces T cells to undergo apoptosis. Several features of this process were identified. The expression of an intact Fas protein is a requirement for CD4-mediated T cell death. Mice homozygous for the lpr mutation which are defective in the expression of Fas and in their ability to delete lymphocytes apoptotically fail to delete anti-CD4-reactive T cells. Sessile anti-CD4-reactive T cells leave their homing environment in lymphoid organs and modulate their cell surface molecules, e.g. CD2, CD3, CD4. A massive influx of lymphoid cells with null-cell phenotype occurs in the blood where they begin to reexpress cell surface markers. With their arrival in the circulation, anti-CD4-reactive T cells develop features of DNA degradation typical of apoptosis. More than one third of the circulating lymphoid cells show apoptotic features 7-8 h after anti-CD4 injection. Their frequency declines subsequently presumably due to their physical disintegration via shedding of apoptotic bodies and phagocytosis. Our data show that when not obliged to the activation process by the antigen receptor, CD4 can mediate deletion signals. Thus, besides functioning as coreceptor with the antigen receptor, CD4 has a function of its own in facilitating the induction of apoptosis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0014-2980
pubmed:author
pubmed:issnType
Print
pubmed:volume
24
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1549-52
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
CD4 engagement induces Fas antigen-dependent apoptosis of T cells in vivo.
pubmed:affiliation
Department of Microbiology and Immunology, New York Medical College, Valhalla 10595.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't