Linked Life Data

9610909

Source:http://linkedlifedata.com/resource/pubmed/id/9610909

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1998-7-17
pubmed:abstractText
To gain insights into the development and regulation of immune responses, we have studied the phenotype, cytokine profiles, activation requirements, and susceptibility to apoptosis of naive CD4, Th1, Th2 polarized effectors, resting memory, and memory effector cells. T cell receptor (TCR) transgenic mice were utilized as a source of enriched naive cells that could be used to generate effector and memory populations. The direct comparison of these populations, which all bear the same TCR, has revealed some interesting distinctions. When restimulated with antigen, effector populations secrete high titers of cytokines in polarized patterns. Retaining their polarized profile, memory cells secrete low levels and memory effector cells secrete very large levels of cytokine. Unlike naive CD4 T cells, effector cell proliferation is not dependent on classic co-stimulation but does require a threshold level of TCR signaling that can be enhanced by accessory interactions. Memory cells have intermediate requirements for co-stimulation/accessory interactions. However, different thresholds of activation are required for production of various cytokines, with requirements for production of interleukin (IL) 2 >> interferon-gamma > IL-4. CD4 subsets also differ dramatically in their susceptibility to apoptosis. Naive Th2 effectors and resting memory cells undergo activation-induced cell death (AICD) 4-7 days after antigen stimulation. In contrast, both primary and memory Th1 effectors undergo rapid AICD mediated by Fas/FasL within 0.5-2 days after stimulation. AICD is substantially blocked by IL-2 and transforming growth factor-beta1, resulting in impressive effector expansion. The process of memory development from effector populations remains mysterious, but these studies suggest roles for cytokines in promoting survival.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1524-9557
pubmed:author
pubmed:issnType
Print
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
181-7
pubmed:dateRevised
2008-3-18
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Regulation of T cell subsets from naive to memory.
pubmed:affiliation
University of California at San Diego, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Review