Acceleration of Wound Regeneration by Implantation of CD34-Mononuclear Cell from Human Cord Blood

ABSTRACT

PURPOSE: Cord blood stem cells are easily obtainable and have characteristics of higher proliferative potential and lower immunogenicity and with benefits in allogenic transplantation for wound treatment. To provide treatment evidence of cord blood stem cell on burn injury, CD34+ (hematopoietic lineage) and CD34- cells (mesenchymal stem cells lineage) were isolated and applied to full thickness skin wounds for evaluation of their effect. METHODS: Mononuclear cell layer was separated by Ficoll- Paque from human cord blood, followed by selection of CD34+, - cells. Two full-thickness wounds were made on dorsal area of ICR mice with 8 mm punch. CD 34+, - cell suspension was injected into the wound sites and wound healing rate was measured every 3 days with analysis of neo- vascularization. Immunohistochemical study for stem cell survival and TGF-beta1 was performed. RESULTS: The wound healing rate of CD34- , CD34 + and control group was 34.73%, 9.24%, 5.132% on day 3 and 82.60%, 64.45% 76.20% on day 9 respectively. The CD34- group showed a significantly higher wound healing rate (p<0.01). The CD34- group revealed a relatively well organized epidermis and showed a remarkably increased neo-vascularization. Anti-human nuclei was detected on CD 34- group. TGF-beta 1 was stained all groups with no differences. CONCLUSION: CD34- mononuclear cells group showed increased wound healing than the control and CD34+ mononuclear cells treated group. CD34- mononuclear cells enhanced epithelization and neo-vascularization by means of differentiation into endothelial cells, myofibroblast and so on. We can conclude that isolated CD34- mononuclear cells can be helpful for burn wound.