Double‐edged effects of neuropeptide substance P on repair of cutaneous trauma

To explore further the role of substance P (SP) in wound healing and scar formation, SP concentrations in wounds of scalded rats were assayed. Expressions of apoptosis‐associated genes in fibroblasts cultured with SP were detected. SP concentrations in superficial wounds increased earlier than those in deep wounds. SP was associated with an increased proliferation and a decreased apoptosis of fibroblasts. It had a greater influence on keloid fibroblasts than on hypertrophic scar fibroblasts by elevating the expression of proliferating cell nuclear antigen and BCL‐2 in fibroblasts. Spantide completely suppressed the effects of SP on hypertrophic scar fibroblasts, and partly inhibited its effects on keloid scar fibroblasts. SP may play an important role in wound healing by promoting wound fibroblast proliferation and inhibiting apoptosis. It may also participate in pathological scar formation by modulating the expression of apoptosis‐associated genes. SP is postulated to play a dual role in wound repair.     

Molecular dissection of abnormal wound healing processes resulting in keloid disease

Keloids are locally aggressive scars that typically invade into healthy surrounding skin and cause both physical and psychosocial distress to the patient. These pathological scars occur following minimal skin trauma after a variety of causes including burns and trauma. Although the pathogenesis of keloid disease is not well understood, it is considered to be the end product of an abnormal healing process. The aim of this review was to investigate the molecular and cellular pathobiology of keloid disease in relation to the normal wound healing process. The molecular aberrances in keloids that correlate with the molecular mechanisms in normal wound healing can be categorized into three groups: (1) extracellular matrix proteins and their degradation, (2) cytokines and growth factors, and (3) apoptotic pathways. With respect to cellular involvements, fibroblasts are the most well‐studied cell population. However, it is unclear whether the fibroblast is the causative cell; they are modulated by other cell populations in wound repair, such as keratinocytes and macrophages. This review presents a detailed account of individual phases of the healing process and how they may potentially be implicated in aberrant raised scar formation, which may help in clarifying the mechanisms involved in keloid disease pathogenesis.     

Detection of apoptosis in keloids and a comparative study on apoptosis between keloids, hypertrophic scars, normal healed flat scars, and dermatofibroma

Recent studies have suggested that the regulation of apoptosis during wound healing is important in scar establishment and the development of pathological scarring. In this study, we demonstrate that keloid fibroblasts can be identified as apoptotic cells because of their highly condensed chromatin and discrete nuclear fragments. To further reveal the phenomenon of apoptosis, we quantified the number of terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells in surgically resected tissues of keloids (N = 10), hypertrophic scars (N = 10), normal healed flat scars (N = 10), and dermatofibroma (N = 10). The number of TUNEL-positive cells was relatively low, but was significantly higher for the keloid group compared with the normally healed flat scar group (p = 0.004), suggesting reduced cell survival and increased apoptotic cell death in a subpopulation of keloid fibroblasts. Furthermore, the number of TUNEL-positive cells was significantly higher for the keloid group compared with the dermatofibroma group (p = 0.044), suggesting that a subpopulation of keloid fibroblasts may suppress tumorgenicity at a greater rate than dermatofibroma by undergoing cell death. Hypertrophic scars had significantly higher levels of apoptosis than normally healed flat scars (p = 0.033). Therefore, these results suggest that selected fibroblasts in keloids and hypertrophic scars undergo apoptosis, which may play a role in the process of pathological scarring.     

The effect of the anti-allergic agent avil on abnormal scar fibroblasts.

Abnormal wound healing in humans leads to the formation of hypertrophic scar and keloids. These abnormal scars accumulate excessive extracellular matrix proteins through increased synthesis as well as decreased degradation. In order to find a therapeutic control for scar formation, we investigated the effect of avil (pheniramine maleate) on fibroblasts cultured from abnormal scars in comparison to normal skin. We observed a decrease in the proliferation rate in cells from normal skin (39%), hypertrophic scar (44%), keloid (63%) and in DNA synthesis in cells from normal skin (50%), hypertrophic scar (55%) and keloid (63%) treated with 8 mM avil (72 h). The rate of decrease in collagen synthesis in normal skin (44%), hypertrophic scar (74%) and keloid fibroblast (73%) correlated with changes in DNA synthesis.     

A wound contraction experimental model for studying keloids and wound-healing modulators

Preventing and treating hypertrophic and keloid scars is difficult because of the lack of knowledge about their genesis. Tissue repair can be studied with biocompatible matrices and ex vivo cultures of different cell types. We used an experimental model where collagen gels populated by human fibroblasts underwent progressive contraction, allowing the study of wound healing remodeling. The fibroblast-populated lattices showed the greater contraction of the gel populated by fibroblasts from keloids versus fibroblasts from normal skin. Moreover, fibroblast growth factor (FGF) and transforming growth factor beta (TGF-beta) involved in scar formation were added to the collagen gels populated by normal skin fibroblasts. TGF-beta caused an increase in gel contraction; FGF did not. The mean percentages of contraction of the gels populated by keloid fibroblasts were very similar to the percentages of gels populated by normal skin fibroblasts with added TGF-beta. These observations confirm the existing hypothesis that TGF-beta may be involved in keloid formation.     

Phosphorylation of extracellular signal-regulated protein kinase in cultured keloid fibroblasts when stimulated by platelet-derived growth factor BB.

Abnormal scars result in distressing symptoms and disfiguring blemishes; an understanding of the molecular events that cause such scars, particularly keloids, would make possible the optimisation of both wound healing and treatment. Extracellular signal-regulated protein kinase (ERK) has a crucial role in distinct signalling pathways in different cells, but to date we know of no study on its signalling events in keloid fibroblasts. The purpose of this study was to characterise the expression of tyrosine phosphorylation kinases, particularly that of ERK, in keloids at the protein level by immunoblotting analysis. Studies on phosphorylation were made on cell lysates of three cultures of five different keloid fibroblasts (n = 5), their relatively 'normal' fibroblasts in adjacent skin (rNHDF, n = 5), and normal human dermal fibroblasts (n = 1, standard control). The result showed that ERK signalling molecular protein was more highly phosphorylated in keloid fibroblast culture than in the other two cultures.     

p53 and apoptosis alterations in keloids and keloid fibroblasts

Keloids are the result of a dysregulated wound-healing process and are characterized by formation of excess scar tissue that proliferates beyond the boundaries of the inciting wound. In this study, we investigated the expression of key proteins involved in regulating apoptosis in keloids. Twenty archival paraffin-embedded keloid samples were randomly selected for an immunoperoxidase assay with antibodies against fas, p53, bcl-2, and bcl-x proteins using the target antigen-retrieval technique. Apoptosis was assessed in keloids and normal skin and in keloid and normal fibroblasts by the TdT-mediated dUTP nick-end labeling (tunel) assay on tissue sections, fibroblast cultures, and by flow cytometry for cell suspensions. We found that 18 of 20 keloids expressed p53 protein; bcl-2 was expressed by keloid fibroblasts in 19 of 20 keloids, and all specimens had prominent fas expression throughout the tissue. The distribution of these three antigens was regional within each lesion and followed a consistent pattern of p53 and bcl-2 expression colocalized to the hypercellular, peripheral areas of each keloid in a perinuclear pattern (p < .001). In contrast, an inverse distribution of fas expression was shown, with staining being more diffuse across the cell surfaces and limited to the central, more hypocellular regions in 16 of 17 keloids (p < .001). There was no specific staining pattern in these keloids with antihuman bcl-x. In vitro studies on cultured keloid fibroblasts (derived from six patients) revealed maintenance of the p53+, bcl-2+ phenotype up to passage 10. Neither neonatal nor normal adult skin fibroblasts expressed either antigen but could be induced to express p53 by exposure to adriamycin. Keloid lesions and keloid fibroblasts were found to have lower rates of apoptosis than normal controls. Keloid fibroblasts displayed enhanced apoptosis rates in response to hydrocortisone, γ interferon and hypoxia treatment as compared with normal adult fibroblasts. Focal dysregulation of p53 combined with upregulation of bcl-2 may help produce a combination of increased cell proliferation and decreased cell death in the younger hypercellular areas of the keloid. This phenotype is reversed in the older areas of the keloid and may prevent malignan degeneration, thus favoring normal apoptosis as evidenced by prominent fas expression.     

Fibronectin gene expression differs in normal and abnormal human wound healing

The overproduction of fibronectin and type I collagen in keloids and hypertrophic scars implicates altered regulation of extracellular matrix components as an important aspect of these wound healing pathologies. However, little is known about the similarities and differences in extracellular matrix gene expression during normal and abnormal wound healing. This study compared the content of fibronectin messenger RNA and rates of fibronectin protein biosynthesis in fibroblasts derived from normal skin, normal scar, keloid, and hypertrophic scar. Fibronectin expression was enhanced in cells from both normal and abnormal wounds relative to cells from quiescent normal skin. Matched pairs of normal and keloid fibroblasts from the same individuals were also compared, and three of the four pairs showed higher fibronectin expression by the keloid cells at the levels of messenger RNA and protein synthesis. This was consistent with previous studies showing elevated steady state content of fibronectin in keloid cells relative to normal cells from the same individual. Fibronectin messenger RNA and protein content in the tissues from which these cells were derived was examined by in situ hybridization and immunohistochemistry. These studies revealed that in vivo, the steady state content of fibronectin messenger RNA and protein was highest in abnormal wounds, less in most normal scars, and lowest in normal skin. Thus, fibroblasts from keloids and hypertrophic scars overexpressed fibronectin in vivo relative to normal skin and normal scar and retain this characteristic in vitro relative to normal skin. Although normal scars contained little fibronectin protein and messenger RNA, cultured fibroblasts derived from these scars had contents of fibronectin messenger RNA and rates of biosynthesis in vitro similar to those of keloid fibroblasts. This indicates that the fibronectin regulatory pathway in scar fibroblasts is influenced by the tissue environment. These results are discussed with respect to the relationship of fibronectin expression in keloids, hypertrophic scars, and normal wounds in human beings.     

Expression of transforming growth factor beta 1, 2, and 3 proteins in keloids.

Keloids represent a pathological response to cutaneous injury, creating disfiguring scars with no known satisfactory treatment. They are characterized by an excessive accumulation of extracellular matrix, especially collagen. Transforming growth factor beta (TGF-beta) has been implicated in the pathogenesis of keloids. The three TGF-beta isoforms identified in mammals (TGF-beta1, -beta2, and -beta3), are thought to have different biological activities in wound healing. TGF-beta1 and TGF-beta2 are believed to promote fibrosis and scar formation, whereas TGF-beta3 has been shown to be either scar inducing or reducing, depending on the study. The aim of this study was to characterize expression of TGF-beta isoforms in keloids at the protein level using Western blot analysis. The authors found that TGF-beta1 and -beta2 proteins were at higher levels in keloid fibroblast cultures compared with normal human dermal fibroblast cultures. In contrast, the expression of TGF-beta3 protein was comparable in both the normal (N = 3) and keloid (N = 3) cell lines. These findings, demonstrating increased TGF-beta1 and -beta2 protein expression in keloids relative to normal human dermal fibroblasts further support the roles of TGF-beta1 and -beta2 as fibrosis-inducing cytokines.     

蛋白糖基化抑制剂对病理性瘢痕成纤维细胞Fas蛋白的表达与功能的影响

目的 研究N-糖链合成抑制剂衣霉素对病理性瘢痕成纤维细胞Fas蛋白的表达与诱导凋亡功能的影响.方法 瘢痕疙瘩及增生性瘢痕各5例,以健康皮肤为对照,免疫组织化学法检测组织中成纤维细胞Fas蛋白表达;组织块贴壁法培养成纤维细胞;Western Blot法及流式细胞术检测衣霉素处理及未处理各组成纤维细胞Fas蛋白水平的表达及凋亡率的变化.结果 病理性瘢痕及健康皮肤成纤维细胞胞质及胞膜中均可见Fas蛋白表达;增生性瘢痕、瘢痕疙瘩及健康皮肤成纤维细胞Fas蛋白糖基化水平依次降低,3组成纤维细胞在Fas单克隆抗体(Fas monoelonal antibody,FasMcAb)作用后凋亡率与Fas蛋白糖基化成正相关,衣霉素可明显降低病理性瘢痕成纤维细胞Fas蛋白糖基化水平,但对健康皮肤成纤维细胞Fas蛋白糖基化水平抑制作用不明显.结论 FasMcAb诱导病理性瘢痕成纤维细胞凋亡与成纤维细胞Fas蛋白糖基化水平成正相关,而衣霉素可显著降低成纤维细胞Fas蛋白糖基化水平.     

α-2b干扰素对瘢痕疙瘩成纤维细胞凋亡及端粒酶逆转录酶、bcl-2 mRNA表达的影响

目的 观察α-2b干扰素(IFNα-2b)对瘢痕疙瘩成纤维细胞生长增殖、凋亡及端粒酶逆转录酶(hTERT)、bcl-2 mRNA表达的影响,探讨其在瘢痕疙瘩治疗中的作用机制.方法 进行成纤维细胞原代培养,细胞分别来自8例瘢痕疙瘩标本和8例正常皮肤标本.第3～4代的细胞用于实验.以IFNa-2b作用于体外培养的瘢痕疙瘩和正常皮肤成纤维细胞,MTT法检测成纤维细胞生长增殖情况,应用流式细胞仪观察处理后成纤维细胞凋亡,RT-PCR法检测成纤维细胞hTERT和bcl-2mRNA的表达.结果 IFNα-2b对瘢痕疙瘩和正常皮肤成纤维细胞生长有抑制作用,体外培养的瘢痕疙瘩和正常皮肤成纤维细胞经10 000 U/ml IFNα-2b处理后,能诱导成纤维细胞凋亡发生,RT-PCR检测hTERT和bcb2 mRNA表达降低,和对照组相比,差异有统计学意义(P<0.01),且具有明显的时间依赖性.结论 作为一个负性调节因子,IFNα-2b能抑制瘢痕疙瘩成纤维细胞的生长增殖并诱导成纤维细胞发生调亡,下调成纤维细胞端粒酶活性是其重要作用机制之一.通过抑制端粒酶活性进行抗瘢痕疙瘩治疗可能是一个新途径.     

E2F1蛋白在病理性瘢痕组织中的表达

目的　增生性瘢痕和瘢痕疙瘩是临床上常见的病理性瘢痕 ,是创伤后过度愈合反应的结果 ,以成纤维细胞的异常增殖及合成分泌大量细胞外基质为特征 ,其形成机理尚不清楚 ,研究表明基因失调是其中的关键。E2F基因是细胞周期G1向S期过渡的重要调控因子 ,在调节细胞周期进程和调节细胞增殖过程中起着关键作用。本实验的目的是检测E2F1基因在病理性瘢痕组织中的表达 ,以正常皮肤组织做对照 ,初步探讨E2F1在病理性瘢痕形成中的生物学作用。方法　利用免疫组化ABC法检测正常皮肤、成熟瘢痕、增生性瘢痕和瘢痕疙瘩组织中E2F1蛋白的表达 ,并进行统计学分析。结果　增生性瘢痕和瘢痕疙瘩组织中E2F1蛋白表达两组间无明显差异 ,与正常皮肤、成熟瘢痕对照组比较均有显著性差异 (P <0 .0 1)。结论　E2F1蛋白表达在病理性瘢痕组织中增高 ,促进瘢痕组织中细胞的增生 ,对病理性瘢痕的形成可能起着重要作用     

TGF-beta2 activates proliferative scar fibroblasts

BACKGROUND. Cytokines, such as the transforming growth factor beta (TGF-beta) isoforms, have been linked to the formation of proliferative scars. This study examines the stimulating effects of exogenous TGF-beta2 on cultured keloid, burn hypertrophic scar, and normal skin fibroblasts and whether such effects can be suppressed with TGF-beta2 antibody. METHODS. In vitro, the fibroblast-populated collagen lattice (FPCL) is used in the evaluation of fibroblast activation by measuring contraction of the lattice over time. Primary cultures of fibroblasts were grown from keloids, burn hypertrophic scars, and normal skin using standard cell culture techniques. TGF-beta2 (10 ng/ml) was added to each of the three types of cell cultures and placed on prefabricated FPCLs. Each was tested against their normal control counterparts. TGF-beta2 antibody (100 ng/ml) was then placed on the TGF-beta2-treated FPCLs. All lattices were allowed to contract and areas were measured for 5 days. RESULTS. Compared to controls, keloid fibroblasts were most affected by the addition of exogenous TGF-beta2. Normal skin fibroblasts did not show a significant increase in contraction early on, yet a significant difference was seen as time progressed. The addition of TGF-beta2 antibody inhibited the function of keloid and burn hypertrophic scar fibroblasts. It also reversed the increased contraction of the TFG-beta2-treated proliferative scar fibroblasts. CONCLUSION. By utilizing an in vitro model, we have demonstrated that TGF-beta2 antibody reverses the increased contraction of FPCLs by proliferative scar fibroblasts treated with TGF-beta2. This points to a possible treatment modality in patients afflicted with this disfiguring problem.     

瘢痕成纤维细胞培养及其生物学行为的实验研究

为探讨不同瘢痕在体外培养情况下，其成纤维细胞生物学特性，切取正常皮肤、增生性瘢痕和瘢痕疙瘩分别行体外成纤维细胞原代和传代培养，观察成纤维细胞形态学和生长动力学变化。结果发现，三类细胞的形态学方面没有明显差异，但瘢痕疙瘩成纤维细胞排列更加紊乱，极性消失，有交叉重叠现象。在接种相同的细胞密度和相同的培养条件下，其细胞生长率、分裂指数、克隆形成及ＤＮＡ含量无明显差别。认为，三类细胞在体外培养状态下，其形态学和生长动力学无显著差异，且具有相似的生物学特性。     

093Prostaglandin E2 Inhibits Fibroblast Migration: Implications for Wound Healing

Background : Wound healing is a complex process involving multiple cell types, extracellular matrix components and soluble mediators. Prostaglandin E2 is an important component of the inflammatory response to injury. PGE2 can regulate the fibroblast response to injury via the EP receptor family. Here, we examine PGE2 regulation of fibroblast migration. Our analysis extends to fibroblasts representing a spectrum of wound healing phenotypes. Hypothesis : Prostaglandin E2 mediated inhibition of fibroblast migration is conserved across multiple fibroblast phenotypes. Methods : Primary cultures of human fetal, adult and keloid fibroblasts were used. Analysis of the EP receptor profile for each fibroblast phenotype was conducted using real‐time PCR, Western blot and immunohistochemistry. Fibroblast migration was quantified using a well established in vitro scratch assay. Results : Prostaglandin E2, via EP2/EP4 receptors, inhibits fibroblast migration in all fibroblast phenotypes. Fetal fibroblasts retain a more robust migratory phenotype when compared to normal adult and keloid fibroblasts. Normal adult fibroblasts exhibit a dramatic destabilization of the actin cytoskeleton which accompanies PGE2 inhibition of cell migration. This effect was not observed in fetal or keloid fibroblasts. Conclusions : Fibroblast activity in the wound bed can be altered by inflammatory mediators. The effects of prostaglandin E2 appear to be partially conserved across various fibroblast phenotypes. Variability in the response of these cells, however, indicates that fibroblasts derived from fetal tissue may retain intrinsic altered response mechanisms to endogenous inflammatory mediators.     

Effect of heparin on production of transforming growth factor (TGF)-beta1 and TGF-beta1 mRNA expression by human normal skin and hyperplastic scar fibroblasts

Heparin affects both dermal fibroblast proliferation and collagen and may mediate these effects by altering the levels of transforming growth factor-beta1 (TGF-beta1) production and TGF-beta1 mRNA expression as a wound healing modulator. The purpose of this study is to probe the effect of heparin on TGF-beta1 and TGF-beta1 mRNA production by human normal skin and hyperplastic scar fibroblasts. This research investigates the effect of heparin on TGF-beta1 and TGF-beta1 mRNA production by human normal skin and hyperplastic scar fibroblasts with exposure to 0 microg/mL, 100 microg/mL, 300 microg/mL, or 600 microg/mL heparin for 24, 48, 72, or 96 hours in a serum-free in vitro model. Levels of TGF-beta1 in the supernatants and TGF-beta1 mRNA expression of fibroblasts were determined by enzyme-linked immunosorbent assay (ELISA) and real time RT-PCR, respectively. Heparin (300 microg/mL and 600 microg/mL) stimulated TGF-beta1 production by normal skin (26% to 83%) and hyperplastic scar fibroblasts (63% to 85%), with statistical significance (P < 0.05) at various time points. Heparin (300 microg/mL and 600 microg/mL) also stimulated TGF-beta1 mRNA expression by normal skin (12% to 53%) and hyperplastic scar fibroblasts (33% to 52%), with statistical significance (P < 0.05) at various time points. These effects of heparin on normal skin and hyperplastic scar fibroblasts may have implications for hyperplastic scar formation and wound healing in vivo.     

瘢痕疙瘩成纤维细胞的基因组学研究

目的 寻找瘢痕疙瘩致病相关基因，探讨瘢痕疙瘩的发生机理。方法 利用含1100个人类肿瘤相关基因的cDNA芯片(cDNA—microarray)对耳垂和胸部瘢痕疙瘩及正常皮肤成纤维细胞进行检测，初步分析瘢痕疙瘩成纤维细胞与正常皮肤成纤维细胞基因总体表达的差异，并筛选出差异基因。结果 在耳垂及胸部瘢痕疙瘩成纤维细胞中，分别有8种和17种特异性表达基因被检出。在正常皮肤中特异性表达的细胞增殖抑制基因Mda-7，在耳垂及胸部瘢痕疙瘩成纤维细胞中均未被表达。结论 多种基因参与了瘢痕疙瘩的形成过程，瘢痕疙瘩成纤维细胞与正常皮肤成纤维细胞之间存在基因表达的差异，增殖因子受体PAR-1和增殖抑制基因Mda-7可能参与瘢痕疙瘩的形成。     

Effects of steroids,interferon-2B,or interluekin 1B on apoptosis of fibroblasts from keloid,hypertrophic scars,and normal skin and related signal pathway

Wound healing can lead to hypertrophic scar or keloid formation, characterized by an overabundant extracellular matrix. Current established treatment strategies include surgical resection, triamcinolone steroid injection, pressure therapy, silicone therapy, radiotherapy, etc. Cytokines also play a critical role in the regulation of cellular activities and extracellular matrix metabolism. Interferons (IFN) represent a group of antifibroproliferative agents that inhibit fibroblast proliferation and collagen production, and interleukin (IL)-1β also accelerates hypertrophic scar fibroblasts to produce collagenolytic enzymes, leading to tissue destruction. This study addressed the effects of steroid, IFN α-2b, or IL-1β on apoptosis and cell pathway of fibroblasts from keloids, hypertrophic scars, and normal skins and different responses of different fibroblasts. Six samples of keloid, six samples of hypertrophic scar, and six samples of normal skin were, respectively, collected from patients, and fibroblasts from different sources were cultured in vitro. After different fibroblasts were treated with dexamethasone (0.1 mg/ml) or IFN α-2b (1,000 μ/ml) or IL-1β (200 μ/ml), Bax and Bcl-2 were detected in situ by immunohistochemical staining; deoxyribonucleic acid ladders of different fibroblasts were observed by gel electrophoresis, and relative activated (phospho-) extracellular-signal-regulated kinase (ERK) 1/2 and c-Jun N-terminal kinase (JNK) pathways were detected by the method of fast activated cell-based enzyme-linked immunosorbent assay. In media containing dexamethasone, apoptosis took place in fibroblasts from keloids, hypertrophic scars, and normal skins by gel electrophoresis with increased rate of Bax/Bcl-2. Activated (phospho-) ERK1/2 and activated (phospho-) JNK expressions increased in three different fibroblasts. In media containing IFN α-2b, no apoptosis took place in three different fibroblasts without any change of expressions of Bax and Bcl-2 except for the expression of decreased Bcl-2 in fibroblasts from keloids. Activated (phospho-) ERK1/2 expression decreased in fibroblasts from keloid and hypertrophic scars without any changes of activated (phospho-) JNK expression, and IFN α-2b did not affect both activated (phospho-) ERK1/2 and activated (phospho-) JNK expressions in fibroblasts from normal skin. In media containing IL-1β, apoptosis of fibroblasts from keloids was induced by stimulating activated (phospho-) ERK1/2 and activated (phospho-) JNK pathways; IL-1β could not induce apoptosis of fibroblasts from normal skin (radio of Bax/Bcl-2 decreasing) whose activated (phospho-) ERK1/2 pathway was stimulated without any changes of activated (phospho-) JNK expression. Apoptosis in fibroblasts from hypertrophic scars was induced by activating the JNK pathway and prohibiting the ERK1/2 pathway. The effects of steroid, IFN α-2b, or IL-1β on apoptosis of different fibroblasts were different through different cell signal pathways, although all of them were effective for treatment of abnormal scars.     

TNFR1及Bcl-2在病理性瘢痕组织细胞凋亡中的表达及意义

目的　研究TNFR1和Bcl- 2在病理性瘢痕组织细胞中的表达及其对成纤维细胞凋亡与增殖的影响。方法　取手术切除的增生性瘢痕和瘢痕疙瘩患者各 15例标本 ,正常皮肤 12例标本 ,应用免疫组织化学方法进行检测 ,分析TNFR1和Bcl- 2的表达及分布规律。结果　TNFR1在正常皮肤、增生性瘢痕及瘢痕疙瘩中成纤维细胞的表达阳性率分别为 10 .70 %、3.2 3%和 7.72 % ,TNFR1在正常皮肤组中的阳性表达率明显高于增生性瘢痕组和瘢痕疙瘩组 ,而瘢痕疙瘩组阳性表达率却又明显高于增生性瘢痕组 ,三组间阳性表达率相互比较差异均有显著意义 (P <0 .0 1) ;Bcl- 2在增生性瘢痕组 (19.35 % )和瘢痕疙瘩组 (48.33% )的阳性表达率明显高于正常皮肤组 (4.0 7% ) ,三组间阳性表达率相互比较差异亦均有显著意义 (P <0 .0 1)。结论　Bcl- 2的持续过表达可能是瘢痕疙瘩呈瘤样增生的原因之一。介导的死亡受体凋亡通路受阻及TNFR1介导核转录因子NF -kB的激活 ,表明TNFR1对成纤维细胞的增殖与凋亡具有双重的调节作用。