Seok-Don Park

Control of scarring in adult wounds using antisense transforming growth factor-|[beta]|1 oligodeoxynucleotides

Adult wounds heal with scar formation, whereas fetal wounds heal without scarring and with a lesser inflammatory and cytokine response. We reasoned that a strategy employing antisense oligodeoxynucleotides (ODN) complementary to transforming growth factor (TGF)‐β1 mRNA might decrease the scarring of dermal wounds in the mouse. To evaluate this concept, we tested the effects of antisense ODN targeted to TGF‐β1 mRNA by topical application of the ODN on the skin wound. Phosphorothioation of ODN to retard their degradation. When antisense TGF‐βl ODN were applied on the wound site, there was a marked reduction of scarring compared with a control wound site. This effect of antisense TGF‐β1 ODN on scar formation was associated with decreased expression of the TGF‐β1 gene. However, sense TGF‐pl ODN had no effect on the expression of the TGF‐β1 gene. In addition, control wounds healed with excessive fibrosis compared with the antisense‐treated wounds. In conclusion, our results indicate that antisense TGF‐β1 ODN could be used for ameliorating scar formation during wound healing.

Hemolytic mechanism of cytolysin produced from V. vulnificus

The characteristics of hemolytic action of cytolysin produced from V. vulnificus were investigated in mouse erythrocytes. The cytolysin bound erythrocyte membranes in temperature-independent manner and then lysed cells temperature-dependently. Hemoglobin release by the cytolysin was completely inhibited by the presence of raffinose or melezitose, but K+ release was not affected. The cytolysin-induced hemolysis was always accompanied with the conversion of membrane-bound cytolysin into an oligomer of 210 kDa, corresponding to a tetramer of native cytolysins. Nonesterified cholesterol inactivated the cytolysin by converting active monomeric cytolysin into inactive oligomer. The results suggest that the cytolysin lyses erythrocytes due to the formation of small pores on erythrocyte membrane by cholesterol-mediated oligomerization of the cytolysin.