Abstract

The release of ⁵¹Cr from labelled colon cells was used to assess a possible lymphocytotoxic effect of peripheral blood lymphocytes from patients suffering from recurrent aphthous ulceration. No significant (p > 0·03) difference was observed between the isotope release following incubation with patients' or control lymphocytes. The absence of such a lymphocytotoxic effect, detectable with oral epithelial cells, is discussed in relation to the role of cellular hypersensitivity in the pathogenesis of ulcerative colitis and aphthous ulceration.