ABSTRACT
<p><b>OBJECTIVE</b>To explore the immunosuppressive effect of local transfection of Molluscum contagiosum virus 148 (MC148) gene to allogenous skin graft against rejection.</p><p><b>METHODS</b>MC148 gene was cloned from molluscum contagiosum virus (MCV), and was employed to construct recombinant adenovirus vector (Ad-MC148). The recombinant Ad-MC148 was then locally transfected into a part of the tail skin of eight Lewis rats, which served as skin donors for grafting. The wounds (1 cm x 1 cm) were produced on the tails of 16 Wistar rats, and they were then randomly divided into control (C, n=8, with grafting of skin from donor rats without transfection), and transfection (T, n=8, with grafting of skin from donor rats with transfection of the recombinant Ad-MC148) groups. The expression of MC148 mRNA gene in T group was detected on 6 post operation hour( POH) and 2, 3, 7 and 10 post operation day (POD), and the results were expressed by the ratio of absorption value (A) between MC148 gene and beta-actin. The survival time of skin grafts in both groups was compared. Gross examination of grafted skin was carried out from 7 POD on in both groups, and the pathomorphological changes were examined in both groups on 7 POD.</p><p><b>RESULTS</b>The MC148 gene expression in rat skin of T group could be identified in 6 POH, and it reached the peak on 3 POD (A(MC148 mRNA) / A(beta_actin) = 0.86), and then subsided thereafter, but it maintained for 10 days. The survival time of the grafts in T group was (15.0 +/- 2.0) days, and it was significantly longer than that in C group (8.5 +/- 3.4) days, (P < 0.01). Gross and microscopic examination showed that the tail skin of T group appeared ruddy on 7 POD, with little leukocytic infiltration in subcutaneous tissue; it began to turn black after 12 to 20 PODs. On the other hand, the tail skin of C group began to turn black and to shed off on 7 POD, with evident leukocytic infiltration in subcutaneous tissue and dermis.</p><p><b>CONCLUSION</b>Local transfection of MC148 gene may promote immunosuppression by inhibiting leukocytic infiltration after allogenous skin transplantation.</p>