Antigen-presenting human T cells and antigen-presenting B cells induce a similar cytokine profile in specific T cell clones (original) (raw)

1993, European Journal of Immunology

Antigen-presenting human T cells and antigen-presenting B cells induce a similar cytokine profile in specific T cell clones* One of the factors that may influence the cytokine secretion profile of aTcell is the antigen-presenting cefi (APC). Since-activated human-T cells have been described to express major histocompatibility complex (MHC) class 11 molecules as well as costimulatory molecules for Tcell activation, like e.g. ICAM-1, LFA-3 and B7, they might play a role as APC and be involved in the regulation of T-Tcell interactions.To define further the role of Tcells as APC we tested their capacity to induce proliferation and cytokine production in peptide-or allospecific T cell clones and compared it with conventional APC, like B lymphoblasts (B-LCL) or HTLV-1-transformed T cells, or with non-classical APC, like activated keratinocytes or eosinophils. CD4+, DP-restricted T cell clones specific for a tetanus toxin peptide (amino acids 947-967) and CD4+, DR-restricted allospecific T cell clones produced interleukin (1L)-2, IL-4, tumor necrosis factor-a and interferon-y (IFN-y) after phorbol 12-myristate 13-acetate and ionomycin stimulation and a more restricted cytokine pattern after antigen stimulation. Dose-response curves revealed that the antigen-presenting capacity of activated, MHC class II+, B7+ Tcells was comparable to the one of B-LCL. Both APC induced the same cytokine profile in the T cell clones despite a weaker proliferative response with Tcells as APC. Suboptimal stimulations resulted in a lower IFN-y/IL-4 ratio. Cytokine-treated, MHC class 11+ keratinocytes and eosinophils differed in the expression of adhesion molecules and their capacity to restimulate T cell clones. The strongly ICAM-1-positive keratinocytes induced rather high cytokine levels. In contrast, eosinophils, which express only low densities of MHC class I1 and no or only low levels of adhesion molecules (B7, ICAM-1 and LFA3), provided a reduced signal resulting in a diminished IFN-yhL-4 ratio. We conclude that non-classical APC differ in their capacity to restimulate T cell clones, whereby the intensity of MHC class I1 and adhesion molecules (B7, ICAM-1) expressed seems to determine the efficacy of this presentation.