title: L3T4 (CD4+) cells that mediate contact sensitivity to trinitrochlorobenzene express I-A determinants.
abstract: The present study has further characterized the T cell-mediated inflammatory response of contact sensitivity (CS) to the hapten trinitrochlorobenzene (TNCB) in mice. A discernible CS response was found to be induced as early as 2 days after epicutaneous application of TNCB. The response peaked on Days 4 to 5 and it then declined to a nearly undetectable level by Days 10 to 11. Examination of the draining lymph nodes demonstrated that development of CS coincided with an increase in cellular proliferation and in the total number of cells present. Despite a severalfold increase in the cellular contents of the draining lymph nodes of sensitized mice, the relative percentages of most subsets of T cells remained unchanged. Flow cytometric studies revealed that the subpopulation of T cells characterized as Thy 1.2+ L3T4+ I-A+ increased substantially in comparison to its presence in unsensitized mice. Whether the Thy 1.2+ L3T4+ I-A+ cells that increased following sensitization represented the effector population that mediates CS was then examined. Four-day immune lymph node T cells or L3T4 cells positively selected from them were capable of adoptively transferring CS to normal mice. However, these cells, after treatment with anti-Ia antibody or anti-I-A monoclonal antibody and complement, were unable to transfer CS. These findings imply that expression of I-A determinants may indicate antigen-induced T cell activation in vivo and that L3T4 cells that mediate CS are I-A positive.
authors.affiliation: Department of General Medical Sciences, Research Institute of the Cleveland Clinic Foundation, Ohio 44195.
authors.forename: S C
authors.initials: SC
authors.lastname: Gautam
authors.forename: J A
authors.initials: JA
authors.lastname: Matriano
authors.forename: N F
authors.initials: NF
authors.lastname: Chikkala
authors.forename: M G
authors.initials: MG
authors.lastname: Edinger
authors.forename: R R
authors.initials: RR
authors.lastname: Tubbs
mesh_terms: D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis*; D003877:Dermatitis, Contact / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D000949:Histocompatibility Antigens Class II / Q000032:analysis*; D006968:Hypersensitivity, Delayed / Q000276:immunology; D016219:Immunotherapy, Adoptive; D008198:Lymph Nodes / Q000166:cytology; D008213:Lymphocyte Activation; D051379:Mice; D008809:Mice, Inbred C3H; D013601:T-Lymphocytes / Q000276:immunology*; D014301:Trinitrobenzenes / Q000276:immunology
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000949:Histocompatibility Antigens Class II; D014301:Trinitrobenzenes