Linked Life Data

2478302

Source:http://linkedlifedata.com/resource/pubmed/id/2478302

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1989-12-7
pubmed:abstractText
At least two biologically significant responses are triggered by the crosslinking of the T-cell receptor (TcR) on the surface of cloned cytotoxic T lymphocytes (CTL): synthesis and secretion of macrophage-activating factor(s) (MAF) that can be attributed to interferon-gamma (IFN) and release of preformed cytolytic granules. We directly compared the molecular requirements for synthesis and secretion of IFN and secretion of granule enzymes triggered in the same cell by the same activating ligand (antigen or monoclonal antibody (mAb) to TcR). An increase in the surface density of activating ligand (immobilized anti-TcR mAb) enhanced both secretion of IFN and secretion of granules. Secretion of IFN occurred immediately after synthesis: only low (but detectable) levels of IFN were detected in cell cytosolic or particulate fractions isolated from Percoll gradients of lysed CTL, while very high levels of IFN were found in the stimulated CTL culture fluids. Inhibitors of RNA synthesis and protein synthesis blocked secretion of IFN, but did not inhibit release of preformed cytolytic granules. The requirement for TcR crosslinking in triggering both secretion of granules and secretion of IFN from CTL was pharmacologically reproduced by the synergistic action of PMA, a protein kinase C activator, and the Ca2+ ionophore A23187. Both secretion of IFN and secretion of granules were absolutely dependent upon extracellular Ca2+: EGTA completely blocked both TcR- and PMA/A23187-induced secretion of IFN and exocytosis of granules. These studies suggest that similar molecular mechanisms are involved in secretion of newly synthesized IFN and secretion of preformed cytolytic granules. One notable difference between the molecular requirements for the two secretory events was a much lower concentration requirement for PMA for IFN synthesis and secretion than for granule secretion in the synergistic interactions with A23187. Implications of these studies for the exocytosis model of cell-mediated cytotoxicity are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0008-8749
pubmed:author
pubmed:issnType
Print
pubmed:volume
124
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
64-76
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Similar molecular requirements for antigen receptor-triggered secretion of interferon and granule enzymes by cytolytic T lymphocytes.
pubmed:affiliation
Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland 20892.
pubmed:publicationType
Journal Article