表皮生长因子受体抑制剂吉非替尼诱导人表皮角质细胞凋亡的研究

目的:探讨表皮因子受体抑制剂吉非替尼对分离培养的人表皮角质细胞的生长抑制及其诱导凋亡的作用机制,为探寻其对皮肤的毒副作用机制奠定基础。方法:采用分散酶分离表皮细胞,无血清培养法进行表皮细胞的培养,MTT法检测吉非替尼对角质细胞生长的影响,Annexin V-FITC/7-AAD双染流式细胞仪检测细胞凋亡,Western blotting检测Bcl-2、bim的变化,采用caspase-3试剂盒检测caspase-3活性的变化。结果:以分散酶分离法成功得到8例人角质细胞,吉非替尼对人角质细胞生长有显著的抑制作用,并能显著诱导细胞发生凋亡,其作用呈明显的量效依赖性。吉非替尼能明显提高bim表达水平,促进caspase-3的活性。结论:吉非替尼通过调节Bcl-2家族蛋白及激活caspase-3诱导人角质细胞凋亡,抑制角质细胞增殖,这可能是其皮肤毒性的分子生物学基础。

Niche regulation of corneal epithelial stem cells at the limbus

Among all adult somatic stem cells, those of the corneal epithelium are unique in their exclusive location in a defined limbal structure termed Palisades of Vogt. As a result, surgical engraftment of limbal epithelial stem cells with or without ex vivo expansion has long been practiced to restore sights in patients inflicted with limbal stem cell deficiency. Neverthe- less, compared to other stem cell examples, relatively little is known about the limbal niche, which is believed to play a pivotal role in regulating self-renewal and fate decision oflimbal epithelial stem cells. This review summarizes relevant literature and formulates several key questions to guide future research into better understanding of the pathogenesis of limbal stem cell deficiency and further improvement of the tissue engineering of the corneal epithelium by focusing on the limbal niche.

Ex vivo differentiation of multipotent adult progenitor cells to skin epidermal cells

Objective： By establishing the indirect contact co-culture system, we studied the in vitro condition for MAPCs differentiating into epidermal cells and the transformation of MAPCs into epidermal cell phenotype. Methods： Cell culture insert membrane was used for substitute basal membrane and MAPCs, fibroblast cells （FCs） and mixture of MAPCs and epidermal cells and FCs were separately implanted into 2 sides of it. PKH26 was used to label cloned MAPCs; type IV collagen rapid adhering method was used to isolate and culture the skin epidermal cells from l-day-old SD rat. Results： Part of the MAPCs transformed into cells expressing keratin in the presence of peripheral epithelia and FCs. Type Ⅳ collagen rapid adhering method successfully selected rats＇ epidermal stem cells. The mixture of the 2 kinds of cells or indirect culture might promote the differentiation through mesenchymal factors secreted by dermis FC. Conclusion： We were the first to have established the in vitro model of MAPCs differentiation into epidermal cells, in which MAPCs were transformed into epithelium-like cells.

Related gene expressions in anti-keratinocyte aging induced by Ganoderma lucidum polysaccharides

Objective:To examine the level of expression of anti skin aging gene of Ganoderma lucidum polysacchayides and clarify its mechanism with anti aging of this ancient Chinese medicine.Methods:HacaT cell of keratinocytes lines were cultured and treated with the polysaccharides.The total RNA was extracted with Trizol reagent and cDNA was synthesized by reverse thanscription.The obtained cDNAs were then fluorescently labeled with cy3 and cy5 respectively and hybridized with gene expressing pedigree cDNA chip.The images were scanned and analyzed with special software.The scan data were analyzed with software and checked by real time PCR.Results:Among total 18 346 human genes,the expression of 103 ones was up-regulated and 378 ones down-regulated.It was demonstrated evidently that Ganoderma lucidum polysaccharides affected the expression of genes of anti skin aging.Two ways are anastomotic.Conclusion:it is concluded by analysis of function of these up-regulation and down-regulation genes that Ganoderma lucidum polysaccharides may play an important role in boosting cell growth and against skin aging.It shows that the results of gene array reliable by real time PCR.

Lymphocytes in patients with psoriasis promote proliferation of ker-atinocytes

Objective: To analyze the effect of lymphocytes on proliferation of keratinocytes in patients with psoriasis. Methods: Lymphocytes in lesion and peripheral blood were isolated and amplified, then cultured together with normal keratinocytes. By MTT method, the living cells were quantified in the mixed culture. Results: Compared with normal controls, lymphocytes from lesion and peripheral blood of psoriasis both promote the proliferation of keratinocytes (P<0. 01 and P<0. 05 respectively). The concentrations of IL-2 and IFN-7 in the mixture of lesion lymphocytes and keratinocytes were significantly higher than that of controls. Tripterygium glycosides inhibited this promotion. Conclusion: Lymphocytes in patients with psoriasis (mainly Th1 cell) play an important role in proliferation of keratinocytes. This psoriasis cell model is useful for studies on signal transduction in psoriasis.

A study of chitosan blend film as a carrier of corneal endothelial cells

In order to evaluate the cytocompatibility and biocompatibility of a new kind of chitosan blend film as a carrier of corneal endothelial cell, rabbit corneal endothelial cells cultured in vitro were breeded onto the film. After a cell monolayer formed, the scanning electron micrography was performed. After inplanted into anterior chamber, slit lamp observation, thickness metering, specular microscopy and HE staining were performed at random time after operation to evaluate the biocompatibility. Inflmmnation in anterior, thickness of cornea, cell density, hexagonality and cell size of the surgical cornea were taken as the indexes of biocompatibility. The cultured cells exhibited a confluent monolayer 10 days after incubation, which proved the satisfactory cytocompatibility of this film. Biocompatibility assay results suggested the implantation feasibility of the film as a carder of corneal endothelial cells.

Antagomir Dependent MicroRNA-205 Reduction Enhances Adhesion Ability of Human Corneal Epithelial Keratinocytes

Objective To investigate the effect of microRNA-205 reduction by antagomirs on adhesion ability of normal human corneal epithelial keratinocytes(NHCEKs).Methods Antagomir-205,complementary and inhibitory to microRNA-205,was used to suppress endogenous microRNA-205 in NHCEKs.The adhesion ability of treated NHCEKs was then assessed by cell adhesion assay.Immunoblot and immunohistochemistry were conducted to determine the level of two focal adhesion-related proteins,focal adhesion kinase(FAK) and paxillin(Pax).Phalloidin staining was performed to measure the level of filamentous actin in antagomir-treated NHCEKs.Results Antagomir-205 markedly reduced the level of microRNA-205 in NHCEKs and significantly enhanced adhesion ability of NHCEKs(P<0.01).Further protein analysis validated that inhibition of mi-croRNA-205 increased the number of phosphorylated FAK and phosphorylated Pax,and decreased filamen-tous actin.Conclusion Our findings suggest that microRNA-205 has down-regulating effect on cell motility in NHCEKs.

EFFECT OF HUMAN AMNIOTIC MEMBRANE ON CORNEAL EPITHELIUM AND YAC-1 CELL

Objective To study the effect of the amniotic membrane on enhancing the proliferation ofcorneal epithelia and YAC-1 cell. Methods After the primary culture of the rabbit's corneal epithelia and YAC-1 cells, they were seeded on the upper surface or stromal matrix side of amniotic membrane respectively. The proliferation results were observed by MTT test. Results The amniotic membrane was found significantly enhancing the proliferation of corneal epithelia on the d1 ,d3 , and d5 after culture. The proliferation rate was 28.93% ,23.32% ,23.41 % (P<0 .05) respectively, but the d7 proliferation rate was 20.72% (P> 0.05). On the dl , d3 , d7 after culture , the YAC-1 cells proliferation rate was 34 .87% ,36 .28% ,33 .86% (P< 0.01) respectively. Conclusion Our results demonstrated that the amniotic membrane could enhance the proliferation of both corneal epithelia and YAC-1 cells significantly. Although amniotic membrane has been suggested as an ideal material for reconstruction of ocular surface, special attention should be paid during amniotic membrane transplantation for treating ocular surface lesion resulted from epibulbar tumors.

Cytocompatibility of Three Corneal Cell Types with Amniotic Membrane

Rabbit limbal corneal epithelial cells,corneal endothelial cells and keratocytes were cultured on amniotic membrane. Phase contrast microscope examination was performed daily. Histological and scan electron microscopic examinations were carried out to observe the growth,arrangement and adhesion of cultivated cells. Results showed that three corneal cell types seeded on amniotic membrane grew well and had normal cell morphology. Cultured cells attached firmly on the surface of amniotic membrane. Corneal epithelial cells showed singular layer or stratification. Cell boundaries were formed and tightly opposed. Corneal endothelial cells showed cobblestone or polygonal morphologic characteristics that appeared uniform in size. The cellular arrangement was compact. Keratocytes elongated and showed triangle or dendritic morphology with many intercellular joints which could form networks. In conclusion,amniotic membrane has good scaffold property,diffusion effect and compatibility with corneal cells. The basement membrane side of amniotic membrane facilitated the growth of corneal epithelial cells and endothelial cells and cell junctions were tightly developed. The spongy layer of amniotic membrane facilitated the growth of keratocytes and intercellular joints were rich. Amniotic membrane is an ideal biomaterial for layering tissue engineered cornea.

In-vitro cultivation of normal human oral keratinocytes

Abstract:Objective To establish a method for culturing normal human oral keratinocytes.Methods Specimens obtained from healthy humans undergoing oral surgery were dissociated into single cell suspensions by dispase and trypsin. The cells were grown in serum-free medium. Morphological characteristics were studied under light microscope and electron microscope. Cytokeratins were shown by immunohistochemistry.Results Cells could be maintained in culture up to 4-5 passages or 30-50 days. Electron microscope revealed that there were desmosomes and tonofibrils in the oral keratinocytes. The cells showed positive staining for cytokeratin antibody. Conclusion Human oral keratinocytes have been successfully grown in serial culture.

Expression of carbonic anhydrase Ⅳ in rabbit corneal endothelial cells

Objective To demonstrate the molecular expression of carbonic anhydrase Ⅳ (CA Ⅳ) in rabbit corneal endothelium.Methods Reverse transcriptase polymerase chain reaction (RT-PCR) was performed using cultured and fresh rabbit corneal endothelial total RNA and specific primers for CA Ⅳ. The RT-PCR product was subcloned and sequenced. Immunoblotting and indirect immunofluorescence staining were performed to detect protein expression and distribution of CA Ⅳ using fresh and cultured rabbit corneal endothelium and rat anti-CA Ⅳ polyclonal antibody. Results RT-PCR screening gave positive bands at the predicted size for CA Ⅳ from fresh and cultured rabbit corneal endothelium. Sequencing further confirmed the identity of CA Ⅳ in corneal endothelium. Immunoblotting analysis showed a single band at 52 kDa for freshly isolated and cultured endothelial cells. Indirect immunofluorescence staining revealed an apparent positive staining in cultured endothelial cells.Conclusion Carbonic anhydrase Ⅳ is expressed in rabbit corneal endothelium, which could contribute to the transendothelial HCO 3 - flux that is necessary to maintain corneal hydration and transparency.

Therapeutic efficiency of tissue-engineered human corneal endothelium transplants on rabbit primary corneal endotheliopathy

To evaluate the therapeutic efficiency of tissue-engineered human corneal endothelia (TE-HCEs) on rabbit primary corneal endotheliopathy (PCEP),TE-HCEs reconstructed with monoclonal human corneal endothelial cells (mcHCECs) and modified denuded amniotic membranes (mdAMs) were transplanted into PCEP models of New Zealand white rabbits using penetrating keratoplasty.The TE-HCEs were examined using diverse techniques including slit-lamp biomicroscopy observation and pachymeter and tonometer measurements in vivo,and fluorescent microscopy,alizarin red staining,paraffin sectioning,scanning and transmission electron microscopy observations in vitro.The corneas of transplanted eyes maintained transparency for as long as 200 d without obvious edema or immune rejection.The corneal thickness of transplanted eyes decreased gradually after transplanting,reaching almost the thickness of normal eyes after 156 d,while the TE-HCE non-transplanted eyes were turbid and showed obvious corneal edema.The polygonal corneal endothelial cells in the transplanted area originated from the TE-HCE transplant.An intact monolayer corneal endothelium had been reconstructed with the morphology,cell density and structure similar to those of normal rabbit corneal endothelium.In conclusion,the transplanted TE-HCE can reconstruct the integrality of corneal endothelium and restore corneal transparency and thickness in PCEP rabbits.The TE-HCE functions normally as an endothelial barrier and pump and promises to be an equivalent of HCE for clinical therapy of human PCEP.

Cytotoxicity and enhancement activity of essential oil from Zanthoxylum bungeanum Maxim.as a natural transdermal penetration enhancer

The aim of this present study is to investigate the effect of Zanthoxylum bungeanum oil （essential oil from Z. bungeanum Maxim.） on cytotoxicity and the transdermal permeation of 5-fluorouracil and indomethacin. The cy- totoxicity of Z. bungeanum oil on dermal fibroblasts and epidermal keratinocytes was studied using an MTT （3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide） assay. The rat skin was employed to determine the percutaneous penetration enhancement effect of Z. bungeanum oil on hydrophilic and lipophilic model drugs, i.e., 5-fluorouracil and indomethacin. The secondary structure changes of the rat stratum comeum （SC） were determined using attenuated total reflectance-Fourier transform infrared spectroscopy （ATR-FTIR）, and saturated solubilities and SC/vehicle partition coefficients of two model drugs with and without Z. bungeanum oil were also measured to un- derstand its related mechanisms of action. It was found that the half maximal inhibitory concentration （ICs0） values of Z. bungeanum oil were significantly lower in HaCaT and CCC-ESF-1 cell lines compared to the well-established and standard penetration enhancer Azone. The Z. bungeanum oil at various concentrations effectively facilitated the percutaneous penetration of two model drugs across the rat skin. In addition, the mechanisms of permeation en- hancement by Z. bungeanum oil could be explained with saturated solubility, SC/vehicle partition coefficient, and secondary structure changes of SC.

Essential oil from Zanthoxylum bungeanum Maxim. and its main components used as transdermal penetration enhancers: a comparative study

Our previous studies had confirmed that the essential oil from Zanthoxylum bungeanum Maxim. （Z. bungeanum oil） could effectively enhance the percutaneous permeation of drug molecules as a natural transdermal penetration enhancer. The aim of the present study is to investigate and compare the skin penetration enhancement effect of Z. bungeanum oil and its main components on traditional Chinese medicine （TCM） active components. Toxicities of Z. bungeanum oil and three selected terpene compounds （terpinen-4-ol, 1,8-cineole, and limonene） in epidermal keratinocytes （HaCaT） and dermal flbroblast （CCC-ESF-1） cell lines were measured using an MTT （3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide） assay. Five model drugs in TCM external preparations, namely osthole （OT）, tetramethylpyrazine （TMP）, ferulic acid （FA）, puerarin （PR）, and geniposide （GP）, which were selected based on their lipophilicity denoted by IogKo^w, were tested using in vitro permeation studies in which vertical Franz diffusion ceils and rat abdominal skin were employed. The secondary structure changes of skin stratum corneum （SC） and drug thermodynamic activities were investigated to understand their mechanisms of action using Fourier transform infrared （FTIR） spectroscopy and saturation solubility studies, respectively. It was found that Z. bungeanum oil showed lower toxicities in both HaCaT cells and CCC-ESF-1 cells compared with three terpene compounds used alone. The enhancement permeation capacities by all tested agents were in the following increasing order： terpinen-4-ol=1,8-cineole〈limonene〈Z, bungeanum oil. The mechanisms of permeation enhancement suggested that these enhancers promoted the skin permeation of drugs mainly by affecting SC lipids. These results indicated that Z. bungeanum oil exhibited better performance in enhancing the skin permeation of active components in TCM preparations.

TLR3 activation induces S100A7 to regulate keratinocyte differentiation after skin injury

Human S100A7 (psoriasin) is highly expressed in psoriasis and other inflammatory diseases; however, the function of S100A7 in wound repair remains largely unknown. Here we demonstrated that skin injury increased the expression of S100A7. Damaged cells from wounded skin induced the expression of S100A7 via the activation of Toll-like receptor 3 (TLR3) followed by the activation of p38 MAPK. S100A7, in turn, acted on keratinocytes to induce the expression of terminal differentiation marker gene loricrin through the activation of p38 MAPK and caspase-1. The differentiation of keratinocytes induced by S100A7 resulted in skin stratification, thus efficiently promoting wound closure. Taken together, our results demonstrate that the activation of TLR3 accelerates wound closure via the induction of S100A7 to induce keratinocyte differentiation. These findings also provide new insights into the development of different forms of treatment with skin wounds.

Potential candidate cells for constructing tissue-engineered lacrimal duct epithelium: a histological and cytological study in rabbits

Objective： Injury and deficiency of the lacrimal duct epithelium （LDE） can lead to a variety of lacrimal diseases. The purpose of this study was to characterize potential candidate cells for constructing a tissue-engineered LDE. Methods： Different areas of the conjunctiva and lacrimal duct tissue were removed from male adult New Zealand white rabbits for histological evaluation. Hematoxylin and eosin staining and immunohistochemical staining of cytokeratin AEI＋AE3, cytokeratin 4, Ki-67, and MUC5AC were observed by light microscopy. The surface morphologies of different epithelial tissues and cellular structures were examined using field-emission scanning electron microscopy and transmission electron microscopy. Epithelial cells were isolated from tissues and identified by specific markers. In vitro, proliferative ability and Western blot analyses of the proliferating cell nuclear antigen （PCNA） of different epithelial cells cultured in identical environments were investigated and compared. Results： Histologically, the epithelial specific markers, cytokeratin AEI＋AE3 and cytokeratin 4, were expressed in the conjunctiva epithelium and the LDE. Notably, highly proliferative cells stained with Ki-67 were concentrated under the epithelium in a dome structure of the posterior palpebral conjunctiva. Differentiated goblet cells were also found to a lesser extent in this region. Primary palpebral and fornical conjunctival epithelial cells （PFCECs）, bulbar conjunctival epithelial cells （BCECs）, and lacrimal duct epithelial cells （LDECs） were successfully separated from tissues. In vitro, rabbit PFCECs and LDECs grew faster and expressed more PCNA than BCECs. Conclusions： PFCECs are anatomically similar to LDECs. They also have similar morphological characteristics, immune phenotypes, and proliferation features. PFCECs are therefore potential candidate cells to replace LDECs in tissue engineering to treat lacrimal duct diseases.