The Th1 /Th2 immune-type response of the recurrent aphthous ulceration analyzed by cDNA microarray.

BACKGROUND

The reduced ability to activate oral tolerance plays a role in the pathogenesis of some gastrointestinal inflammatory diseases. This activation may reflect a preferential reduction of a T-helper (Th)2- or Th3-type response. In recurrent aphthous ulceration (RAU), genetic and environmental factors may contribute to low tolerance, permitting a cytotoxic reaction against the oral epithelium. The cytokine profile has not permitted the definition of RAU as resulting from enhanced Th1 or Th2 responses. A cDNA microarray study would allow the identification of differentially expressed genes and provide a basis for classification of the immune response.

METHODS

The cDNA from 29 samples of aphthae and from 11 samples of normal mucosa from aphthae-free volunteers were hybridized on microarray membranes with 1176 genes.

RESULTS

Forty-one differentially expressed genes were identified, and a higher expression level of the Th1 gene cluster in RAU was found.

CONCLUSIONS

Microarrays permitted us definition of the gene expression profile of the lesion and identify an increased Th1 activity in RAU lesions.