The presence of gliadin specific, HLA DQ2 restricted T cells in the small intestinal mucosa is a common phenomenon of celiac disease.

The gastrointestinal disorder celiac disease is strongly associated with genes encoding the HLA-DQ2 heterodimer, DQ(1^*0501,β1^*02). We have isolated activated lamina propria derived lymphocytes from small intestinal biopsies of 20 DR3-DQ2+ celiac disease patients (17 treated and 3 untreated) by immunomagnetic positive selection of CD25+ cells after in vitro challenge of biopsies with wheat flour gliadin protein. Gliadin-specific, polyclonal T cell lines were established from all of the 20 patients. Inhibition studies of T cell lines with anti-HLA monoclonal antibodies indicated predominant antigen presentation by DQ2 in patients. Furthermore we generated 9 gliadin-specific T cell clones from 5 patients which all were DQ2 restricted. These data confirm our previous reports in a more limited material of preferential DQ2-restriction of gliadin-specific T cells from the small intestine. In conclusion, our findings strongly indicate that gliadin-specific T cells is a common phenomenon in the small intestinal mucosa of celiac disease patients and they support the notion that most of them recognize gliadin-peptide when presented by the disease associated HLA-DQ heterodimer (1^*0501,β1^*02).