Study of Regulatory Mechanism of Various Growth Factors in Human Epidermal Cells and Fibroblasts

(1) tgf - β对培养的人角质形成细胞生长和分化的影响：tgf - β在0.25 ng/ml以上时抑制人角质形成细胞生长，在细胞周期的G_1/G_0期停止。除非潜伏期过长，否则这种生长停滞是可逆的。(2) tgf - α在正常表皮和银屑病表皮中的作用：用免疫细胞化学方法检测tgf - α在正常表皮和银屑病表皮中的定位。tgf - α主要存在于正常表皮上层。tgf - α在银屑病表皮除基底层外的整个表皮中均存在。这一结果表明银屑病表皮中tgf - α比正常表皮增加。为了进一步证实tgf - α的升高，采用ELISA法测定正常表皮提取物和银屑病表皮提取物中tgf - α的含量。正常表皮提取物中tgf - alpha含量为1.45 <正负> 1.06 ng/g湿组织，银屑病受累表皮中tgf - alpha含量为6.71 <正负> 0.75ng/g湿组织。(3)IL-6对培养的人角质形成细胞生长分化的影响：IL-6刺激人角质形成细胞生长。免疫细胞化学研究表明，I1-6和IL-6受体存在于表皮基底层。提示IL-6可能以自分泌的方式刺激角质形成细胞的生长。IL-6对人角质形成细胞的分化无明显影响。(4)血小板来源内皮细胞生长因子（platelet-derived endothelial cell growth factor, PD-ECGF）对体外培养人角质形成细胞生长分化的影响：PD-ECGF刺激人角质形成细胞生长。然而，PD-ECGF对人角质形成细胞的分化无明显影响。(5)建立了一种利用天花素免疫荧光染色和细胞荧光技术定量角质形成细胞分化的新方法。

(1) Effects of TGF-beta on growth and differentiation of cultured human keratinocytes : TGF-beta inhibited human keratinocyte growth over 0.25 ng/ml and arrested in G_1/G_0 phase of cell cycle. This growth arrest was reversible unless incubation duration is too long.(2) Roles of TGF-alpha in normal and psoriatic epidermis : The localization of TGF-alpha in normal and psoriatic epidermis was examined immunocytochemically. TGF-alpha was observed mainly in the upper layer of normal epidermis. In contrast, TGF-alpha was present intensely through the whole epidermis except basal layer in psoriatic epidermis. This result indicates the increase of TGF-alpha in psoriatic epidermis compared to normal epidermis. To further confirm the increase of TGF-alpha, the amount of TGF-alpha in extracts of normal and psoriatic epidermis was measured by ELISA. The amount TGF-atpha in the extracts of normal epidermis was 1.45 <plus-minus> 1.06 ng/g of wet tissue, while the amount in psoriatic involved epidermis was 6.71 <plus-minus> 0.75ng/g of wet tis(3) Effects of IL-6 on growth and differentiation of cultured human keratinocytes : IL-6 stimulated human keratinocyte growth. Immuno-cytochemical study showed that I1-6 and IL-6 receptor were present in basal layer of epidermis. This suggests that IL-6 possibly stimulates keratinocyte growth in autocrine manner. IL-6 has no clear effect on differentiation of human keratinocytes.(4) Effects of platelet-derived endothelial cell growth factor (PD-ECGF) on growth and differentiation of cultured human keratinocytes : PD-ECGF stimulated human keratinocyte growth. However, PD-ECGF has no clear effect on differentiation of human keratinocytes.(5) A new method for quantifying keratinocyte differentiation using immuno-fluorescent staining of involucrin and cyto-fluorography was established.