Matches in SemOpenAlex for { <https://semopenalex.org/work/W1970891808> ?p ?o ?g. }
- W1970891808 endingPage "70" @default.
- W1970891808 startingPage "52" @default.
- W1970891808 abstract "The programmed death of thymocytes and T cells was studied. Injection of anti-TCR antibodies into adult mice caused the specific deletion of CD4+ CD8+ thymocytes, an effect that was largely reversed by cyclosporin A. Surprisingly, using either anti-TCR antibodies or superantigens, it was found that the susceptibility of these thymocytes to clonal deletion changed during ontogeny. Double positive thymocytes from newborn and young (3 week old) mice were readily depleted, whereas thymocytes from 1 week old mice were relatively refractory. The differences between these groups could not be accounted for by cell surface TCR expression, TCR-mediated early signal transduction pathways such as phosphoinositide hydrolysis or Ca2+ mobilization, or differences in susceptibility to Dex- or ionomycin-induced programmed cell death. These results suggest that there is a relatively synchronous wave of maturing thymocytes that are susceptible to deletional signals during fetal life and shortly after birth, but not 7 days after birth. By 3 weeks of age, the next wave (or waves) of susceptible cells have populated the thymus. These observations closely follow the experimental model known as neonatal tolerance, and we suggest that the failure to tolerize 1 week old mice in that system reflects an alteration in the cells' susceptibility to clonal deletion. In a separate set of experiments exploring the mechanisms of PCD, it was found that although the activation- and glucocorticoid-induced PCD pathways were distinct (being distinguishable by their sensitivity to CsA and the glucocorticoid antagonist RU-486), they were mutually antagonistic. Attempts to identify the level of the antagonism failed to demonstrate any direct interference between the two stimuli, up to and including the transcription and translation of a GRE-controlled reporter gene. Based upon these observations, we propose the following model of thymocyte development: glucocorticoids eliminate thymocytes with little or no avidity for self; antagonism between glucocorticoids and cellular activation allows thymocytes that recognize self with low or moderate avidity to survive (positive selection); activation of thymocytes that recognize self with high avidity dominates the antagonistic effect of glucocorticoids, leading to PCD (negative selection)." @default.
- W1970891808 created "2016-06-24" @default.
- W1970891808 creator A5005700483 @default.
- W1970891808 creator A5027511826 @default.
- W1970891808 creator A5037682468 @default.
- W1970891808 date "1991-12-01" @default.
- W1970891808 modified "2023-09-28" @default.
- W1970891808 title "Thymocyte Activation and Death: a Mechanism for Molding the T Cell Repertoire" @default.
- W1970891808 cites W1547990742 @default.
- W1970891808 cites W1549519372 @default.
- W1970891808 cites W1552751328 @default.
- W1970891808 cites W1559184092 @default.
- W1970891808 cites W1588468987 @default.
- W1970891808 cites W1597881730 @default.
- W1970891808 cites W1599176230 @default.
- W1970891808 cites W1600662889 @default.
- W1970891808 cites W1605634265 @default.
- W1970891808 cites W1612135387 @default.
- W1970891808 cites W1621064629 @default.
- W1970891808 cites W1642708427 @default.
- W1970891808 cites W1871261170 @default.
- W1970891808 cites W1898775203 @default.
- W1970891808 cites W1945675794 @default.
- W1970891808 cites W1967702267 @default.
- W1970891808 cites W1969868671 @default.
- W1970891808 cites W1975597891 @default.
- W1970891808 cites W1976340479 @default.
- W1970891808 cites W1986006829 @default.
- W1970891808 cites W1987557547 @default.
- W1970891808 cites W1989402394 @default.
- W1970891808 cites W1989952069 @default.
- W1970891808 cites W1991605327 @default.
- W1970891808 cites W1992953623 @default.
- W1970891808 cites W1999298531 @default.
- W1970891808 cites W2003501749 @default.
- W1970891808 cites W2006665853 @default.
- W1970891808 cites W2019058265 @default.
- W1970891808 cites W2019544334 @default.
- W1970891808 cites W2025369435 @default.
- W1970891808 cites W2033360952 @default.
- W1970891808 cites W2035135369 @default.
- W1970891808 cites W2038377343 @default.
- W1970891808 cites W2051349356 @default.
- W1970891808 cites W2054969526 @default.
- W1970891808 cites W2060903877 @default.
- W1970891808 cites W2065164093 @default.
- W1970891808 cites W2070379407 @default.
- W1970891808 cites W2070397307 @default.
- W1970891808 cites W2080052508 @default.
- W1970891808 cites W2084609653 @default.
- W1970891808 cites W2085124463 @default.
- W1970891808 cites W2086417745 @default.
- W1970891808 cites W209938675 @default.
- W1970891808 cites W2101462909 @default.
- W1970891808 cites W2108897330 @default.
- W1970891808 cites W2119725374 @default.
- W1970891808 cites W2129207936 @default.
- W1970891808 cites W2146346171 @default.
- W1970891808 cites W2153206751 @default.
- W1970891808 cites W2160277752 @default.
- W1970891808 cites W2165748470 @default.
- W1970891808 cites W2173828780 @default.
- W1970891808 cites W241168973 @default.
- W1970891808 doi "https://doi.org/10.1111/j.1749-6632.1991.tb33438.x" @default.
- W1970891808 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/1793231" @default.
- W1970891808 hasPublicationYear "1991" @default.
- W1970891808 type Work @default.
- W1970891808 sameAs 1970891808 @default.
- W1970891808 citedByCount "21" @default.
- W1970891808 crossrefType "journal-article" @default.
- W1970891808 hasAuthorship W1970891808A5005700483 @default.
- W1970891808 hasAuthorship W1970891808A5027511826 @default.
- W1970891808 hasAuthorship W1970891808A5037682468 @default.
- W1970891808 hasConcept C114684123 @default.
- W1970891808 hasConcept C134018914 @default.
- W1970891808 hasConcept C167672396 @default.
- W1970891808 hasConcept C190283241 @default.
- W1970891808 hasConcept C19317047 @default.
- W1970891808 hasConcept C203014093 @default.
- W1970891808 hasConcept C24998067 @default.
- W1970891808 hasConcept C2776090121 @default.
- W1970891808 hasConcept C2776989580 @default.
- W1970891808 hasConcept C2777868816 @default.
- W1970891808 hasConcept C2778954852 @default.
- W1970891808 hasConcept C2780841215 @default.
- W1970891808 hasConcept C31573885 @default.
- W1970891808 hasConcept C36333154 @default.
- W1970891808 hasConcept C54355233 @default.
- W1970891808 hasConcept C86803240 @default.
- W1970891808 hasConcept C8891405 @default.
- W1970891808 hasConcept C95444343 @default.
- W1970891808 hasConceptScore W1970891808C114684123 @default.
- W1970891808 hasConceptScore W1970891808C134018914 @default.
- W1970891808 hasConceptScore W1970891808C167672396 @default.
- W1970891808 hasConceptScore W1970891808C190283241 @default.
- W1970891808 hasConceptScore W1970891808C19317047 @default.
- W1970891808 hasConceptScore W1970891808C203014093 @default.
- W1970891808 hasConceptScore W1970891808C24998067 @default.