Antigen-presenting cell function in induction of helper T cells for cytotoxic T-lymphocyte responses: evidence for antigen processing.

AUTOR(ES)

Weinberger, O

RESUMO

We demonstrate that splenic adherent cells (SACs) play an active role in the presentation of H-2Kk antigen for an alloreactive cytotoxic T-lymphocyte (CTL) response. If antigen is incubated with SACs for 12 hr, they will provide maximal stimulation and present the antigen in the context of their Ia molecules. UV irradiation of these SACs, prior to the 12-hr incubation with H-2Kk antigen, abrogates this stimulatory capacity. Macrophage-bound antigen is not sufficient for stimulation of a response; a second signal is required as well, that, in our system, is provided by phorbol myristic acetate. The SACs are involved in the activation of helper T cells; however, they are not required for presentation of antigen to the precytotoxic T-lymphocyte, which requires two signals for activation, one provided by antigen and the other by a T-cell-derived helper factor.

Documentos Relacionados

• Two genetically identical antigen-presenting cell clones display heterogeneity in antigen processing.
• Calcium response of helper T lymphocytes to antigen-presenting cells in a single-cell assay.
• The specific direct interaction of helper T cells and antigen-presenting B cells.
• T helper cell subsets require the expression of distinct costimulatory signals by antigen-presenting cells.
• Antigen-presenting dendritic cells provide the reducing extracellular microenvironment required for T lymphocyte activation