CD56 expression is profoundly downregulated in the coeliac gut, but not blood, both in percentage of cell expression, and expression intensity.

<p>CD56 expression was analysed on non-T cells, non-γδ T cells, and Vδ1 T cells in terms of frequency (A) and mean fluorescence intensity (B). Flow cytometry plots are also shown for representative control and coeliac donors (C). For simplicity, data is shown for a paediatric population only, but similar trends were noted in the adult cohort. *P <0.05, **P<0.01, ***P<0.001, error bars show standard error of the mean.</p

γδ T cells from the coeliac small intestine display a functional “effector memory” phenotype.

<p>(A) Differential expression of CD45RA and CD27 by γδ T cells was used to analyse naïve (CD45RA+/CD27+), central memory (TCM; CD45RA-/CD27+), effector memory (TEM; CD45RA-/CD27-) and terminally differentiated (TEMRA; CD45RA+/CD27-) subsets in the blood, small intestinal epithelium and lamina propria from paediatric patients. (B) Expression of IFN-γ by unstimulated and stimulated epithelial γδ T cells, control n=5, coeliac n=4. *P <0.05, **P<0.01, ***P<0.001, error bars show standard error of the mean.</p

Innate lymphocyte subsets are altered in the intestinal epithelium and lamina propria of both paediatric and adult coeliac donors, compared with controls.

<p>Scatterplots showing percentages of small intestinal innate lymphocyte subsets in (A) epithelium, and (B) lamina propria for paediatric (n=34 controls, n=19 UCD) and adult coeliac (n=7 controls, n=8 TCD, n=6 UCD) donors and matched control subjects. All subsets are expressed as a percentage of the total T cell population. TCD = treated coeliac donors (on gluten free diet), UCD = untreated coeliac donors (diet contains gluten). Dotplots show flow cytometry data from gut epithelial cells (C), and lamina propria cells (D) for representative control and coeliac donors, where Vα7.2 ⁺ /CD161⁺ populations describe MAIT cells. *P <0.05, **P<0.01, ***P<0.001, error bars show standard error of the mean.</p