Figure 2.

Exploiting oral gluten challenge to elicit disease-specific T cells in vivo. Short-term oral gluten challenge in treated CD mobilises a polyclonal gluten-specific CD4⁺ T-cell population in vivo. Patients with CD consume a gluten-containing cereal for 3 days, and blood is collected on day 6 to isolate peripheral blood mononuclear cells. By greatly expanding the gluten-specific T-cell population in vivo, a range of functional and immunophenotyping approaches can be readily employed without the need for prolonged in vitro expansion. Overnight functional assays such as IFN-γ ELISpot can be used for high throughput T-cell epitope mapping. Single-cell sorting by flow cytometry can be applied to the antigen-specific CD4⁺ T cells identified by proliferation or IFN-γ secretion, and these cells can be analysed for TCR repertoire or cultured to generate T-cell clones.