Linked Life Data

1671359

Source:http://linkedlifedata.com/resource/pubmed/id/1671359

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1991-3-14
pubmed:abstractText
We have investigated the requirements for allogeneic stimulation of human CD4 T cells using HLA class II products expressed on various cellular backgrounds. Human (class II-negative RJ2.2.5 mutant) B cell lines transfected with HLA-DR or -DQ cDNA clones were efficient stimulators for highly purified CD4 T cells. HLA-DR-transfected mouse L cells or IFN-gamma-induced human fibroblasts, although able to function as accessory cells for T cell responses to the mitogen PHA, failed to stimulate strong T cell alloresponses. On the basis of these observations, we have employed class II transfectants to address the following questions: (a) do CD45RA and CD45R0 subpopulations differ in their allogeneic activation requirements, (b) are these subpopulations skewed in their recognition of HLA-DQ vs. HLA-DR in a manner which might support the concept that CD45RA T cells are involved in HLA-DQ-restricted suppressor inducer functions and (c) by using transfectants expressing individual HLA-DR or -DQ heterodimers in combination with limiting dilution analysis, can one for the first time obtain estimates of precursor frequencies for allogeneic cells recognizing each of these class II isotypes? Our results show that CD45RA and CD45R0 T cells respond comparably to optimal numbers of stimulator cells. However, when CD45RA and CD45R0 T cell populations depleted of endogenous accessory cells were cultured with limiting numbers of stimulator cells, CD45R0 cells generally responded more strongly, consistent with the elevated levels of various adhesion molecules known to be expressed by this population. Further, we found a similar representation of responses to HLA-DR and -DQ antigens among populations expressing CD45RA and CD45R0 isoforms. Finally, the precursor frequencies of allogeneic CD4 T cells responding to particular HLA-DR alleles were higher than to -DQ, but only by a factor of about 1.6, indicating that HLA-DQ recognition may occur more frequently than implied from previous antibody blocking studies.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0014-2980
pubmed:author
pubmed:issnType
Print
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
79-88
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Allorecognition of HLA-DR and -DQ transfectants by human CD45RA and CD45R0 CD4 T cells: repertoire analysis and activation requirements.
pubmed:affiliation
ICRF Human Tumor Immunology Group, London.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't