Linked Life Data

8103743

Source:http://linkedlifedata.com/resource/pubmed/id/8103743

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1993-10-12
pubmed:abstractText
Protective immunity against mycobacteria is dependent on antigen-specific T cells. Current evidence suggests that not only helper T cells that activate infected macrophages but also cytotoxic T cells (CTL) that lyse infected macrophages are involved in protection. Mycobacterium-specific CD4+ CTL are readily detectable among primary peripheral T cells but what proportion of CD4+ T cells display cytotoxic activity is not known. Whether the cytotoxic CD4+ T cells are identical to or distinct from those that produce interferon (IFN)-gamma is also unknown. In addition, studies on CTL in mycobacterial infections have focused primarily on selected antigens like hsp65 but have not analyzed systematically whether other mycobacterial antigens can activate CTL as well. These issues are relevant not only to a further understanding of protective immunity and immunopathology but also may have implications for the design of effective vaccines. To start addressing these issues, we have studied a large panel of CD4+ T cell clones specific for a broad range of mycobacterial antigens, and analyzed their ability to lyse mycobacterium-pulsed target cells and to release IFN-gamma and interleukin (IL)-4. Our results show that the vast majority of CD4+ T cell clones are able to lyse mycobacterial antigen-pulsed target cells, and that those CTL can be triggered by a wide variety of mycobacterial antigens. CD4+ CTL released high levels of IFN-gamma, but low or nondetectable levels of IL-4. In contrast, control tetanus toxoid-specific T cell clones or lines displayed poor or weak cytotoxic activity and released high levels of IL-4. The antimycobacterial clones appeared to be heterogeneous in their levels of cytotoxic activity and IFN-gamma release. Interestingly one T cell clone was able to lyse only mycobacterium-pulsed macrophages but not B cells suggesting possible selectivity in target cell recognition for some CTL. These in vitro data have to be interpreted with some caution. Nevertheless they confirm and significantly extend previous observations and suggest that mycobacteria preferentially induce CD4+ T helper type 1 (Th1)-like cells that display cytotoxic activity, and release high levels of IFN-gamma but no or little IL-4. The induction of such Th1 like cells is specific for mycobacteria since tetanus toxoid induced T cells that were poorly or not cytolytic and secreted high levels of IL-4.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0014-2980
pubmed:author
pubmed:issnType
Print
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2189-95
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Mycobacteria induce CD4+ T cells that are cytotoxic and display Th1-like cytokine secretion profile: heterogeneity in cytotoxic activity and cytokine secretion levels.
pubmed:affiliation
Department of Immunohaematology, University Hospital Leiden, The Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't