The Consensus Conference was funded by Debra UK, Debra Austria and Debra Ireland. (Although the authors have acknowledged in other unrelated publications their extramural support for their own epidermolysis bullosa-related research programmes, none of these has provided funding for the Consensus Conference or the generation of this report.)

Objective-The delivery of autologous progenitor cells into ischemic tissue of patients is emerging as a novel therapeutic option. Here, we report the potential impact of cultured adipose tissue-derived cells (ADSC) on angiogenic cell therapy. Method and Results-ADSC were isolated from C57Bl/6 mouse inguinal adipose tissue and showed high expression of ScaI and CD44, but not c-kit, Lin, CD34, CD45, CD11b, and CD31, compatible with that of mesenchymal stem cells from bone marrow. In coculture conditions with ADSC and human aortic endothelial cells (ECs) under treatment with growth factors, ADSC significantly increased EC viability, migration and tube formation mainly through secretion of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF). At 4 weeks after transplantation of ADSC into the ischemic mouse hindlimb, the angiogenic scores were improved in the ADSC-treated group, which were evaluated with blood flow by laser Doppler imaging (LDI) and capillary density by immunostaining with anti-CD31 antibody. However, injected ADSC did not correspond to CD31, von Willebrand factor, and ␣-smooth muscle actin-positive cells in ischemic tissue. Conclusion-These

ABSTRACT

The role of bone marrow cells in repairing ectodermal tissue, such as skin epidermis, is not clear. To explore this process further, this study examined a particular form of cutaneous repair, skin grafting. Grafting of full thickness wild-type mouse skin onto mice that had received a green fluorescent protein-bone marrow transplant after whole body irradiation led to an abundance of bone marrow-derived epithelial cells in follicular and interfollicular epidermis that persisted for at least 5 mo. The source of the epithelial progenitors was the nonhematopoietic, platelet-derived growth factor receptor α-positive (Lin − /PDGFRα + ) bone marrow cell population. Skin grafts release high mobility group box 1 (HMGB1) in vitro and in vivo, which can mobilize the Lin − /PDGFRα + cells from bone marrow to target the engrafted skin. These data provide unique insight into how skin grafts facilitate tissue repair and identify strategies germane to regenerative medicine for skin and, perhaps, other ectodermal defects or diseases.

Rad51 siRNA could enhance the sensitivity to CDDP in cancer cells both in vitro and in vivo. Our results suggest that the combination of CDDP and Rad51 siRNA will be an effective anti-cancer protocol.

Transforming growth factor-␤ (TGF-␤) plays a major role in regulating connective tissue deposition by controlling both extracellular matrix production and degradation. In this study, we show that TGF-␤ transcriptionally represses both basal and tumor necrosis factor-␣-induced collagenase (matrix metalloprotease-1) gene expression in dermal fibroblasts in culture, whereas it activates its expression in epidermal keratinocytes. We demonstrate that this differential effect of TGF-␤ on collagenase gene expression is due to a cell type-specific induction of distinct oncogenes of the Jun family, which participate in the formation of AP-1 complexes with different trans-activating properties. Specifically, our data indicate that the inhibitory effect of TGF-␤ in fibroblasts is likely to be mediated by jun-B, based on the following observations: (a) TGF-␤ induces high levels of jun-B expression and (b) over-expression of jun-B mimics TGF-␤ effect in inhibiting basal collagenase promoter activity and preventing tumor necrosis factor-␣-induced trans-activation of the collagenase promoter. In contrast, TGF-␤ induction of collagenase gene expression in keratinocytes is preceded by transient elevation of c-jun proto-oncogene expression. Over-expression of c-jun leads to trans-activation of the collagenase promoter in both cell types, suggesting that c-jun is a ubiquitous inducer of collagenase gene expression. Transfection of keratinocytes with an antisense c-jun construct together with a collagenase promoter/reporter gene construct inhibits basal and TGF-␤-induced up-regulation of the collagenase promoter activity, implying that c-jun mediates TGF-␤ effect in this cell type. Collectively, our data suggest differential signaling pathways for TGF-␤ in dermal fibroblasts and epidermal keratinocytes, leading to cell type-specific induction of two AP-1 components with opposite transcriptional activities.

IL-10, originally isolated from mouse helper T cells, is a cytokine with regulatory functions on a number of interleukins. In this study we show that recombinant human IL-10 affects the expression of several genes involved in extraceliular matrix synthesis and remodeling in human dermal fibroblast cultures. As judged by Northern blot analyses, type I collagen gene expression was downregulated, while collagenase and stromelysin gene expression were markedly enhanced by IL-10. No effect on tissue inhibitor of metalloproteases mRNA levels was noted. Transient transfections of skin fibroblasts with type I collagen promoter/chloramphenicol acetyl transferase reporter gene constructs showed downregulation by IL-10, suggesting inhibition at the transcriptional level. When compared with control cultures, incubation with IL-10 resulted in a decrease in immunostaining of fibroblast cultures with antibodies to human type I collagen. In contrast, immunostaining of such IL-10-treated cultures with antibodies to human coliagenase resulted in an increase in immunostaining. This study suggests a role for IL-10 in the breakdown and remodeling of the extracellular matrix. (J. Clin. Invest. 1994. 94:2489-2492

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