MESSENGER-RNA DIFFERENTIAL DISPLAY OF COLONIC MUCOSA CELLS IN ULCERATIVE-COLITIS

Involvement of mucosal cells in inflammatory bowel disease (IBD) may b e a sequenced process and the molecular difference between involved an d uninvolved cells might implicate a possible mechanism in the disease process. The aim of this study was to compare gene expression between involved and uninvolved colonic mucosa cells in an individual with ul cerative colitis (UC) and to clone, sequence, and identify those diffe rentially expressed genes. mRNA differential display was used to ident ify the gene expression in the mucosa of the UC patient. Anchored olig o(dT) primers and random 5' oligonucleotide 10-mer were used to carry out polymerase chain reaction on reverse-transcribed RNA (RT-PCR). The amplified cDNAs were displayed on a standard sequencing gel and compa risons were drawn between each two lanes representing either involved or uninvolved cells from a specific combination of two primers. Wherev er differences were noted between lanes, the bands were reamplified us ing PCR, cloned into specialized vectors for positive selection, and t hen confirmed by dot blot. The cloned genes were then sequenced and co mpared with the GenBank database. About 1200 mRNA species were display ed in the sequencing gel. Among them, 106 fragments were differentiall y expressed between the two groups. Twenty-five of those differentiall y displayed gene fragments have been isolated, reamplified, and cloned for sequencing and dot blot analysis. Seventeen of the fragments were differentially expressed using the dot blot technique. Among those 25 gene fragments, 14 have homology to known genes and 11 have no match to any reported genes. Those matched known genes included genes for pa rathyroid tumor, T cell receptor-beta, alpha-nascent polypeptide-assoc iated complex, ovarian cancer, and myeloblast. This is the first study using mRNA differential display to observe differential gene expressi on between involved and uninvolved mucosa cells in UC and it shows tha t differential display is a rapid method for characterizing gene chang es in vivo in ulcerative colitis. The results from this study may prov ide useful information and facilitate further gene studies in this dis ease. (C) 1997 Academic Press.