PHENOTYPICAL CHARACTERIZATION OF PERIPHERAL-BLOOD T-CELLS IN PATIENTSWITH CELIAC-DISEASE - ELEVATION OF ANTIGEN-PRIMED CD45RO(-LYMPHOCYTES() T)

Increased numbers of gamma delta T-cell-receptor-braring (TCR gamma de lta(+)) lymphocytes are present in the small intestinal epithelium of patients with coeliac disease (CoD). In this study the phenotypic char acteriztics of peripheral blood T cells from 14 untreated CoD patients and 14 healthy age- and sex-matched controls were determined with spe cial emphasis on TCR gamma delta(+) lymphocytes. We also studied sampl es taken from 15 CoD patients who were on gluten-free diet (GFD). Two- and three-colour flow cytometry analyses were performed using a whole -blood lysing method. There was no significant difference between the percentages of TCR gamma delta(+) lymphocytes in patients and controls . However, the amount of delta TCS1(+) lymphocytes was significantly l owered in untreated patients (0.48 +/- 0.42% in CoD versus 0.86 +/- 0. 57% in controls, P < 0.05). The percentage of CD45RO(+) T cells, which are a primed population of T cells including memory cells, was signif icantly raised in the peripheral blood of untreated patients. This phe nomenon was most prominent within the TCR gamma delta(+) population (8 3.9 +/- 12.2% in CoD versus 65.5 +/- 14.7% in controls, P<0.01), but t he same applies to CD45RO(+) TCR alpha beta(+) and delta TCS1(+) T cel ls. In patients on GFD these changes seem to be at least partly correc ted. Antigen-primed CD45RO(+) T cells have been shown to accumulate in the jejunal epithelium of patients with untreated CoD. The enhanced ' memory activity' also found in the peripheral blood of untreated CoD p atients may result from a continuous antigenic stimulus and this stimu lus could be gluten triggered.