Trefoil factor expression in normal and diseased human salivary glands

Trefoil factors are wound-healing peptides important in protection and heal ing of the human gastrointestinal tract. Their potential for therapy of gas trointestinal ulcers has been established. This study investigated the hypo thesis that trefoil factors are also present in human salivary gland. Tissu es from surgical biopsy specimens were collected fresh into ice and stored in liquid nitrogen. Breast, stomach, and colon constituted positive control s. Trefoil factor mRNAs were detected by reverse transcription polymerase c hain reaction (RT-PCR) or by in situ hybridization (ISH) with formalin-fixe d, paraffin-embedded sections. Amplified DNA fragments were ligated into pG EM-T Easy vector and used to transform competent Escherichia coli JM109, al lowing sequencing to confirm identity of cloned fragments. Generation of am plifiable cDNA was confirmed using primers specific to the ubiquitously exp ressed abl gene. By RT-PCR, TFF1 (pS2) mRNA was detected in 14 of 15 glands , TFF3 (hITF) mRNA in 13, and TFF2 (hSP) in only 1 gland. ISH of 15 glands (7 of which had been studied by RT-PCR) showed the same pattern of expressi on and indicated that TFF1 mRNA was usually expressed at low levels by a fe w mucous cells, whereas TFF3 was produced abundantly by most mucous cells. There was no difference in patterns of expression comparing parotid, subman dibular, and minor mucous glands. Nor was there an obvious relationship bet ween trefoil factor expression and pathology but those glands not expressin g TFF1 or TFF3 had evidence of chronic inflammation or atrophy. Trefoil fac tors are likely to be important in healing, predisposition to, and therapy of, oral diseases. HUM PATHOL 31:509-515. Copyright (C) 2000 by W.B. Saunde rs Company.