Tolerance induction by clonal deletion of CD4⁺8⁺ thymocytes in vitro does not require dedicated antigen‐presenting cells

Abstract

The cellular requirements of T cell tolerance induction in the thymus by clonal deletion was investigated by using an in vitro assay: thymocytes from mice expressing a transgenic TcR specific for lymphocytic choriomeningitis virus (LCMV) and H-2Db were co-cultured with various H-2b cell types as antigen-presenting cells in the presence of the antigenic LCMV peptide. The results revealed that all cell lines examined including embryonic and transformed fibroblasts, melanoma cells, cortical thymic epithelial cells, lymphomas and neuronal cells induced an antigen dose-dependent deletion of CD4+8+ thymocytes. Similarly, highly enriched accessory cell populations from thymus and spleen (macrophages, dendritic and cortical epithelial cells, i.e. thymic nurse cells) could induce antigen-specific depletion of immature CD4+8+ thymocytes. Depending on the cell type examined micromolar to picomolar concentration of LCMV peptide were required to induce deletion. The effectiveness of deletion by the different cell types did not correlate with their major histocompatibility class I expression level; it was, however, influenced by the presence of ICAM-1 adhesion molecules.

Differential role of IL‐2R signaling for CD8+ T cell responses in acute and chronic viral infections

“…The H-2D b -restricted LCMV glycoprotein (GP) peptide aa 33-41 (gp33 peptide, KAVYNFATM) [58], the I-A b -restricted LCMV GP-derived peptide aa 61-80 (gp61 peptide, GLNGPDIYKGVYQFKSVEFD) [59], the H-2K b -restricted MCMV m38 epitope (316-323, SSPPMFRV) and the H-2D brestricted MCMV m45 epitope (985-993, HGIRNASFI) [38] were purchased from NeoMPS (Strasbourg, France).…”

TCR Antagonism by Peptide Requires High TCR Expression

“…OT-I (V␣2V␤5) and P14 (V␣2V␤8) TCRs were visualized with PE-conjugated mAbs to V␤5 (BD Pharmingen) and V␤8 (BD Pharmingen), respectively (21,22). OT-I and P14 mice were bred to generate P14 ϫ OT-I dual transgenic mice bearing T cells expressing both TCRs.…”

Bcl10/Malt1 Signaling Is Essential for TCR-Induced NF-κB Activation in Thymocytes but Dispensable for Positive or Negative Selection

“…4B). We then studied the role of Bcl10 in peptide-specific apoptosis with the P14 TCR transgenic system in vitro, which is considered as a model for negative selection (30). Thymocytes from P14 TCR transgenic wild-type or Bcl10 Ϫ/Ϫ mice and nontransgenic littermates were isolated and incubated with APCs that have been preloaded with the agonistic p33 peptide.…”