Acquisition of CD80 by Human T Cells at Early Stages of Activation: Functional Involvement of CD80 Acquisition in T Cell to T Cell Interaction

Abstract

The interaction between CD28 on T cells and CD80 on APCs intensifies the linkage between TCR and MHC at the site of contact between T cells and APCs. In this study, we demonstrate that during human T cell/human APC interaction, the autologous or allogeneic human CD4+ T cells become positive for the detection of CD80 at an early stage of activation (24 h). This detection of CD80 is attributable to the acquisition of CD80 from APCs, as opposed to the up-regulation of endogenous CD80, as demonstrated by CD4+ T cells treated with cyclohexamide. Furthermore, no CD80 mRNA could be detected at 24 h in T cells that had acquired CD80 from APCs. CD80 acquisition by T cells from APCs was enhanced upon TCR engagement. The amount of CD80 acquisition by CD4+ T cells was shown to be related to the expression of CD80 on APCs. Using soluble fusion proteins (soluble CTLA-4, CD28, and CD80) to block either CD28 on the surface of T cells or CD80 on the surface of APCs, it was demonstrated that CD80 acquisition by T cells is mediated through its receptors, possibly CD28 interaction. Moreover, we demonstrate that T cells that have acquired CD80 have the ability to stimulate other T cells. These data thus suggest that CD80 acquisition by human T cells might play a role in the immunoregulation of T cell responses.

CD8+ Cytotoxic T-APC Stimulate Central Memory CD8+ T Cell Responses via Acquired Peptide-MHC Class I Complexes and CD80 Costimulation, and IL-2 Secretion

“…2C). These results indicate that, besides previously reported MHC class I and CD80 molecules (11,21,22), CD8 ϩ T cells also acquire the immunological synapse-composed CD54 by DC/ CD8 ϩ T cell interactions (9, 10).…”

The DNA methylation profile of activated human natural killer cells

“…30 Table 2 illustrates more examples of differentially methylated genes from other activated immune cells that appear to be common with NK cell activation. [30][31][32][33][34][35][36][37][38][39] The Th2 cytokine locus has been intensively studied as a model of chromatin dynamics directing gene expression in the immune system. The genes encoding the Th2 cytokines IL4, IL5 and IL13 are clustered in a 160 kb region of chromosome 5q31 in humans.…”

Trogocytosis of CD80 and CD86 by induced regulatory T cells

“…[19][20][21][22] To determine if iTregs shared this ability, iTregs were cocultured with mDCs and the level of CD80 and CD86 expression was measured on iTregs cultured alone, or after coculture with mDCs. To examine CD80 and CD86 acquisition by iTregs, plots were gated on PI 2 CD11c 2 CD4 1 cells.…”