Linked Life Data

6224317

Source:http://linkedlifedata.com/resource/pubmed/id/6224317

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3-4
pubmed:dateCreated
1983-9-20
pubmed:abstractText
The frequency of all precursors of T cells capable of proliferation (PTL-p) and of all cytotoxic T-cell clones (CTL-p) was determined for different thymocyte subpopulations using a high cloning-efficiency, Con A and growth factor driven, limit-dilution assay and a lectin-mediated, non-specific cytotoxic readout. As shown previously, more than 99% of precursors were confined to the medullary-type fraction, isolated by fluorescence activated cell sorting as the 14-15% of thymocytes showing low binding of peanut agglutinin (PNA). However, 20-50% of medullary-type cells appeared incapable of responding in a culture system allowing all peripheral T cells to grow, suggesting that the absolute size of the functional pool was 7-12% of all thymocytes. The 3-4% cortisone-resistant fraction of thymus gave a high precursor frequency (PTL-p 1 in 1.3; CTL-p 1 in 6) and a high cloning efficiency per Thy 1 positive cell (80%) which was nevertheless below that of peripheral T cells. However, only 20-25% of the total thymic PTL-p and CTL-p could be recovered in this fraction. Functional precursors were therefore within both the cortisone-sensitive and the cortisone-resistant subgroups of medullary-type thymocytes. Attempts to induce function in PNA+ cortical-type thymocytes by increasing the level of T-cell growth factors in the cultures gave only a marginal increase, the bulk of small cortical cells remained functionally inert. However, the low frequency of precursors found in the PNA+ fraction (around 1% of that in PNA- thymocytes) was not entirely due to PNA- contaminants since a PNA+, high H-2 blast fraction, representing about 4% of all thymocytes, showed a significant, although still low, PTL-p and CTL-p frequency amounting to less than 1% of the total thymus precursor pool. The relevance of this minor subset is discussed.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0165-6090
pubmed:author
pubmed:issnType
Print
pubmed:volume
5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
179-95
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
The size of functional T-lymphocyte pools within thymic medullary and cortical cell subsets.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Review, Research Support, Non-U.S. Gov't