Adenovirus-mediated expression of antisense RNA transcripts complementary to pig alpha(1,3) galactosyltransferase mRNA inhibits expression of Gal alpha(1,3) Gal epitope.

AIM: To examine the effects of the expression of antisense RNA transcripts complementary to the pig alpha(1,3) galactosyltransferase [alpha(1,3)GT]mRNA on the expression of Gal alpha(1,3) Gal structure (gal epitope) in cultured cell lines. METHODS: Human adenoviral vectors were used to mediate the expression of antisense RNA. The expression levels of H blood group antigens and gal epitopes were analyzed by flow cytometry using FITC-UEA-I and FITC-GS-IB4 lectins, respectively. RESULTS: Recombinant adenoviruses, Ad5anti-sGT600 and Ad5-anti-sGT1100, which express antisense RNA complementary to different regions of the pig alpha(1,3) GT mRNA, were constructed and used to infect cell line of NIH3T3. The results showed about 30% reduction in the expression level of gal epitopes on the surface of NIH3T3 cells. In addition, co-expression of human secretor type alpha(1,2) fucosyltransferase [alpha(1,2)FT]cDNA and antisense RNA complementary to the pig alpha(1,3) GT mRNA led to a further reduction in the gal epitope level. CONCLUSION: Recombinant adenoviruses, Ad5anti-sGT600 and Ad5anti-sGT1100, are effective to down-regulate the gal epitope expression.