Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1993-4-23
pubmed:abstractText
The present study investigated bystander suppression, specific suppression and anergy as mechanisms for oral tolerance. Oral tolerance was induced in mice by a single gastric intubation of 20 mg ovalbumin (OVA) and was evaluated in vitro by the absence of T lymphocyte proliferative responses to OVA after priming by OVA-complete Freund's adjuvant (CFA). T lymphocyte unresponsiveness was antigen specific, systemic and was not affected by the vehicle used for immunization. T lymphocytes derived from tolerant popliteal lymph nodes (PLN) responded to an acetone precipitate (AP) of mycobacteria present in CFA; this response was not suppressed by co-culture with OVA, thereby arguing against a mechanism of bystander suppression in our system. Responses of PLN T lymphocytes derived from OVA-CFA primed, non-tolerant mice, or those of an OVA-specific T lymphocyte line, were not suppressed by PLN or spleen cells derived from OVA tolerant mice. These results excluded the possibility that oral tolerance was induced and maintained by a mechanism of specific suppression. At the cellular level, we found that OVA-tolerant T lymphocytes did not produce interleukin-2 (IL-2) nor express IL-2 receptor in response to OVA stimulation in vitro; both observations are indicative of a state of anergy. Incubation of OVA-tolerant PLN T lymphocytes together with murine recombinant IL-2 for 5 days, released anergic T lymphocytes and a concomitant OVA-specific proliferative response of CD4+ T cells was detected. Taken together, our experimental system excludes the involvement of bystander or specific suppression in the induction of oral tolerance to OVA, and provides direct evidence to show that oral tolerance results from specific T lymphocyte anergy.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0014-2980
pubmed:author
pubmed:issnType
Print
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
935-42
pubmed:dateRevised
2005-11-17
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Direct evidence for anergy in T lymphocytes tolerized by oral administration of ovalbumin.
pubmed:affiliation
Department of Animal Sciences, Hebrew University of Jerusalem, Rehovot, Israel.
pubmed:publicationType
Journal Article