title: Regulatory activity of activated murine peripheral CD4+CD25- T cells: a possible mechanism of feedback regulation on adaptive immunity.
abstract: This study was undertaken to investigate the possibility that peripheral CD4+CD25- T cells, once fully activated, transiently obtain suppressive function against other T cells. CD4+CD25- T cells, isolated from splenocytes of BALB/c mice, were stimulated with anti-CD3 MoAb in the presence of feeder cells for 72 h. The activated CD4+ T cells (T(act)) thus obtained were able to inhibit the activation and proliferation of bystander CD4+ T cells in a non-MHC-restricted manner. T(act)-mediated suppression was cell contact dependent, reversible by exogenous IL-2 as well as anti-GITR antibody. Furthermore, adoptive transfer of T(act) cells significantly downregulated humoral response of BALB/c mice to s.c. immunization with ovalbumin. We argue that suppression mediated by activated CD4+CD25- T cells may play an important role in maintaining homeostasis of the immune system and preventing excessive T-cell responses in vivo.
authors.affiliation: Department of Immunology, Peking University Health Science Center, Beijing, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Lu
authors.forename: W
authors.initials: W
authors.lastname: Xu
authors.forename: Y
authors.initials: Y
authors.lastname: Zhou
authors.forename: P
authors.initials: P
authors.lastname: Lv
authors.forename: X-M
authors.initials: XM
authors.lastname: Gao
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000502:physiology*; D002478:Cells, Cultured; D002999:Clone Cells; D005246:Feedback; D005260:Female; D007108:Immune Tolerance; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism*; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D010047:Ovalbumin / Q000494:pharmacology; D010641:Phenotype
chemical_list: D053645:Interleukin-2 Receptor alpha Subunit; D010047:Ovalbumin