title: In vivo helper activity of enriched populations of antigen-specific T lymphocytes.
abstract: Enrichment of murine antigen-specific T cells was achieved by stimulation of primed lymph node cells with macrophages containing the immunizing antigen. After a week in culture, the in vitro-sensitized lymphocytes had an increased helper activity. Inoculation of 10(7) egg albumin (OVA)-enriched T cells together with hapten coupled to OVA, elevated the number of splenic antihapten-producing cells of primed or unprimed mice. Augmentation of the hapten specific B-cell response could be observed as early as 4 days following the injection of the enriched population and peaked at Day 7. The enhancing effect of the enriched population of antigen-specific T cells was carrier specific since it occurred only in the presence of hapten coupled to the T-cell sensitizer [2,4-dinitrophenol (DNP)-OVA]. When given with the hapten conjugated to an irrelevant carrier [DNP-human gamma globulin (HGG)], the enriched lymphocytes caused a depression in the anti-DNP response. The capacity of in vitro enriched lymphocytes to promote a substantial antigen-specific helper activity (up to 1 anti-DNP producing cell per 10(3) spleen cells) upon adoptive transfer to nonirradiated mice, provides an experimental system for studying B-T collaboration in vivo under the normal physiological conditions.
mesh_terms: D000818:Animals; D000921:Antibody-Producing Cells / Q000276:immunology; D002352:Carrier Proteins / Q000276:immunology; D004136:Dinitrobenzenes / Q000276:immunology; D000939:Epitopes; D005260:Female; D007116:Immunization, Passive; D008211:Lymphocyte Cooperation; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010047:Ovalbumin / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: D002352:Carrier Proteins; D004136:Dinitrobenzenes; D000939:Epitopes; D010047:Ovalbumin