Skin wound healing is a complex event, and interrupted wound healing process could lead to scar formation. The aim of this study was to examine the morphological changes of scar tissue. Pathological staining (HE staining, Masson's trichrome staining, methenamine silver staining) was used to evaluate the morphological changes of regenerating epidermis in normal skin and scar tissue, and immunofluorescence staining to detect the expression of collagen IV, a component of basement membrane (BM), and the expression of integrinβ4, a receptor for BM laminins. Additionally, the expression of CK14, CK5, and CK10 was measured to evaluate the proliferation and differentiation of keratinocytes in normal skin and scar tissue. The results showed that the structure of the skin was histologically changed in scar tissue. Collagen IV, expressed under the epidermis of normal skin, was reduced distinctly in scar tissue. Integrinβ4, expressed in the basal layer of normal skin, was found absent in the basal layer of scar tissue. Additionally, it was found that keratinocytes in scarring epidermis were more proliferative than in normal skin. These results indicate that during the skin wound healing, altered formation of BM may affect the proliferation of keratinocytes, reepithelial and tissue remodeling, and then result in scar formation. Thus, remodeling BM structure during wound repair may be beneficial for improving healing in cutaneous wounds during clinical practice.
Adolescent ; Adult ; Cicatrix ; metabolism ; pathology ; Collagen Type IV ; metabolism ; Female ; Humans ; Integrin beta4 ; metabolism ; Keratinocytes ; cytology ; metabolism ; pathology ; Male ; Skin ; cytology ; metabolism ; pathology

OBJECTIVE: In order to investigate the interaction between the cytokines and keratinocyte and determine the role of cytokines in hyperproliferative of chronic otitis media with cholesteatoma, we observe the expression of matrix metalloproteinase 9 (MMP9), vascular endothelial growth factor (VEGF), keratinocyte growth factor (KGF) and its receptor (KGFR) in middle ear cholesteatoma. METHOD: We examined the expression of MMP9, VEGF, KGF, KGFR and Ki-67 by immunohistochemistry in 50 specimens from chronic otitis media with cholesteatoma and 15 specimens from the normal skin of external auditory meatus. Ki-67 as an evaluation of cholesteatoma proliferation markers were used to detect the keratinocyte proliferative activity. RESULT: (1) The expression of VEGF and MMP9 in cholesteatoma specimens was higher than normal skin, and the difference was statistically significant (t = 4.914, P < 0.01; t = 3.284, P < 0.01). (2) The expression of KGF and KGFR in middle ear tissues was higher than normal skin, and the difference was statistically significant (t = 4.814, P < 0.01; t = 3.104, P < 0.01); The expression of KGF and KGFR increased, and the expression of Ki-67 also correspondly increased in the cholesteatoma. (3) In the tissue MMP9 and VEGF were positive. Mean optical density increased as well. KGF expression also increased accordingly. CONCLUSION MMP9, VEGF, KGF and KGFR proteins played an important role in hyperproliferation of cholesteatoma tissues. VEGF, MMP9 and KGF had a synergistic effect in hyperproliferation of cholesteatoma tissues.
Cholesteatoma, Middle Ear ; pathology ; Cytokines ; metabolism ; Ear Canal ; metabolism ; Ear, Middle ; metabolism ; Fibroblast Growth Factor 7 ; metabolism ; Humans ; Immunohistochemistry ; Keratinocytes ; cytology ; Ki-67 Antigen ; metabolism ; Matrix Metalloproteinase 9 ; metabolism ; Otitis Media ; pathology ; Receptor, Fibroblast Growth Factor, Type 2 ; metabolism ; Vascular Endothelial Growth Factor A ; metabolism

Stromal cells provide a crucial microenvironment for overlying epithelium. Here we investigated the expression and function of a stromal cell-specific protein, stromal cell-derived factor-1 (SDF-1), in normal human skin and in the tissues of diseased skin. Immunohistology and laser capture microdissection (LCM)-coupled quantitative real-time RT-PCR revealed that SDF-1 is constitutively and predominantly expressed in dermal stromal cells in normal human skin in vivo. To our surprise, an extremely high level of SDF-1 transcription was observed in the dermis of normal human skin in vivo, evidenced by much higher mRNA expression level than type I collagen, the most abundant and highly expressed protein in human skin. SDF-1 was also upregulated in the tissues of many human skin disorders including psoriasis, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC). Double immunostaining for SDF-1 and HSP47 (heat shock protein 47), a marker of fibroblasts, revealed that fibroblasts were the major source of stroma-cell-derived SDF-1 in both normal and diseased skin. Functionally, SDF-1 activates the ERK (extracellular-signal-regulated kinases) pathway and functions as a mitogen to stimulate epidermal keratinocyte proliferation. Both overexpression of SDF-1 in dermal fibroblasts and treatment with rhSDF-1 to the skin equivalent cultures significantly increased the number of keratinocyte layers and epidermal thickness. Conversely, the stimulative function of SDF-1 on keratinocyte proliferation was nearly completely eliminated by interfering with CXCR4, a specific receptor of SDF-1, or by knock-down of SDF-1 in fibroblasts. Our data reveal that extremely high levels of SDF-1 provide a crucial microenvironment for epidermal keratinocyte proliferation in both physiologic and pathologic skin conditions.
Adult ; Cell Proliferation ; Chemokine CXCL12 ; genetics ; Epidermal Cells ; Epidermis ; pathology ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Fibroblasts ; metabolism ; Gene Expression Regulation ; Humans ; Keratinocytes ; cytology ; pathology ; Signal Transduction ; Skin Diseases ; genetics ; pathology

In covering wounds, efforts should include utilization of the safest and least invasive methods with goals of achieving optimal functional and cosmetic outcome. The recent development of advanced wound healing technology has triggered the use of cells to improve wound healing conditions. The purpose of this review is to provide information on clinically available cell-based treatment options for healing of acute and chronic wounds. Compared with a variety of conventional methods, such as skin grafts and local flaps, the cell therapy technique is simple, less time-consuming, and reduces the surgical burden for patients in the repair of acute wounds. Cell therapy has also been developed for chronic wound healing. By transplanting cells with an excellent wound healing capacity profile to chronic wounds, in which wound healing cannot be achieved successfully, attempts are made to convert the wound bed into the environment where maximum wound healing can be achieved. Fibroblasts, keratinocytes, adipose-derived stromal vascular fraction cells, bone marrow stem cells, and platelets have been used for wound healing in clinical practice. Some formulations are commercially available. To establish the cell therapy as a standard treatment, however, further research is needed.
Blood Platelets/metabolism ; Cell- and Tissue-Based Therapy ; Diabetes Mellitus, Type 2/complications/pathology ; Fibroblasts/cytology/transplantation ; Humans ; Keratinocytes/cytology/transplantation ; Stromal Cells/cytology/transplantation ; Tissue Engineering ; Ulcer/etiology/therapy ; *Wound Healing

Scar, either hypertrophic scar or keloid, is one of the most common complications due to proliferative disorder of fibrosis in the process of wound healing after burn injuries, trauma, and surgical operations. To repair the cosmetic and functional impairments caused by scars poses a great challenge to all the burn surgery workers. With the advances in both basic research and clinical treatment, the understanding of scar formation and the therapeutic strategies of scar have been improved significantly. However, the remaining problems are still outstanding. In this discussion, the advances and problems in the scientific research in this field, including genetic predisposition, candidate gene, dysfunction of fibroblasts, interaction between fibroblasts and keratinocytes, as well as animal models for hypertrophic scar and keloid were summarized. In addition, the progresses in the clinical therapies are also discussed, including pressure treatment, silicone gel sheeting, corticosteroids, laser, and other emerging treatment strategies. The understanding and treatment of scar will improve in the future with further deepening basic research and clinical trials with stricter standard of assessment.
Burns ; pathology ; Cicatrix ; genetics ; pathology ; therapy ; Fibroblasts ; cytology ; Humans ; Keratinocytes ; cytology

OBJECTIVETo investigate the effect of a novel retinoid CD437 and all-trans retinoic acid (ATRA) in inducing cell apoptosis and inhibiting the proliferation of human epidermoid carcinoma A431 cells and normal human epidermal keratinocytes.

METHODSMTT assay was used to determine the inhibitory effects of CD437 and ATRA on the growth of A431 cells and normal human epidermal keratinocytes, and the cell morphological changes were observed microscopically. Flow cytometry was used to investigate the effect of CD437 and ATRA on the cell cycle and apoptosis.

RESULTSCD437 was more effective than ATRA in inhibiting the proliferation of A431 cells and normal human epidermal keratinocytes. CD437 increased the percentage of sub-G1 populations in A431 cells and induced G1 arrest in normal human epidermal keratinocytes. ATRA appeared to be relatively ineffective for inducing apoptosis in A431 cells as compared to CD437. CD437 did not duce obvious apoptosis in normal human epidermal keratinocytes.

CONCLUSIONCD437 is more effective than ATRA in inhibiting the proliferation and inducing apoptosis in A431 cells and shows selective apoptosis-inducing effect against malignant keratinocytes, suggesting its potential in the prevention or treatment of cutaneous carcinoma.

Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Carcinoma, Squamous Cell ; pathology ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cells, Cultured ; Epidermis ; drug effects ; pathology ; Flow Cytometry ; Humans ; Keratinocytes ; cytology ; drug effects ; Male ; Retinoids ; pharmacology ; Tretinoin ; pharmacology ; Young Adult

OBJECTIVETo investigate the origin of myofibroblasts in oral submucous fibrosis.

METHODSThe oral keratinocytes and fibroblasts were isolated and cultured. The expression of the alpha-smooth muscle actin in the fibroblasts was examined by immunohistochemistry and reverse transcriptase polymerase chain reaction (RT-PCR).

RESULTSNo difference was found in expression of alpha-smooth muscle actin between the fibroblasts that were directly stimulated by arecoline and the control. The expression of alpha-smooth muscle actin in the keratinocyte and fibroblast-cocultured group was higher than in the control group, and higher in fibroblasts cocultured with keratinocytes preprocessed by arecoline than in fibroblasts cocultured with keratinocytes without preprocessed by arecoline.

CONCLUSIONSThe differentiation of myofibroblasts from fibroblasts in oral submucous fibrosis might be induced by the interaction of arecoline and keratinocyte.

Actins ; metabolism ; Arecoline ; pharmacology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Coculture Techniques ; Fibroblasts ; cytology ; metabolism ; Humans ; Keratinocytes ; cytology ; Mouth Mucosa ; cytology ; Oral Submucous Fibrosis ; metabolism ; pathology

OBJECTIVETo clarify expression and subcellular localization of XIAP and XAF1 protein in human normal oral keratinocytes (hNOK) and Tca8113 cells human tongue carcinoma cell line.

METHODSThe hNOKs and Tca8113 cells were cultured in vitro. Expression and subcellular localization of XIAP and XAF1 protein were examined by combination of indirect immunofluorescence and confocal laser scanning microscopy.

RESULTSXIAP expression was weak in the hNOKs and fluorescence staining localized chiefly in the cytoplasm and perinuclear areas. In the Tca8113 cells, high level of XIAP protein could be detected in both the cytoplasm and the nucleus. In the hNOKs, XAF1 distributed mostly in the nucleus. Homogeneous nuclear and cytoplasmic distribution of XAF1 could be visualized in the Tca8113 cells.

CONCLUSIONSIn cancerization of oral mucosa, XIAP protein could play an important antiapoptotic role by overexpression, while XAF1 protein does not appear to antagonize effectively the role of XIAP.

Apoptosis ; Cell Line, Tumor ; Cells, Cultured ; Humans ; Intracellular Signaling Peptides and Proteins ; Keratinocytes ; metabolism ; pathology ; Mouth Mucosa ; cytology ; metabolism ; Neoplasm Proteins ; metabolism ; Tongue Neoplasms ; metabolism ; pathology ; X-Linked Inhibitor of Apoptosis Protein ; metabolism

Defensins and cathelicidins (LL-37) are major antimicrobial peptides (AMPs) of the innate immune system of the human skin. In normal non-inflamed skin these peptides are negligible, but their expression can be markedly increased in inflammatory skin disease such as psoriasis. We designed this study to identify the expressions of LL-37 in normal human keratinocyte (NHK) and HaCaT cells after exposure to stimulants and to investigate difference of LL-37 expression accompanied with cell differentiation status, and come to understand difference of susceptibility to infection in atopic dermatitis and psoriasis. Expressions of LL-37 in NHKs and HaCaT cells were evaluated by using RT-PCR, Western blotting, and immunohistochemical (IHC) staining at 6, 12, and 24 hr post stimulation after exposure to Ultraviolet B irradiation and lipopolysaccharide. And expression of LL-37 in skin biopsy specimens from patients with atopic dermatitis and psoriasis was determined by immunohistochemical analysis. In time-sequential analyses of LL-37 expression revealed that LL-37 was expressed in NHKs, but not in HaCaT cells. IHC analysis confirmed the presence of abundant LL-37 in the epidermis of psoriasis. Therefore we deduced that expression of LL-37 is affected by UV irradiation, bacterial infection, and status of cell differentiation.
Antimicrobial Cationic Peptides/analysis/*genetics ; Blotting, Western ; Cell Line ; Cells, Cultured ; Comparative Study ; Defensins/analysis/genetics ; Dose-Response Relationship, Drug ; Gene Expression/drug effects/radiation effects ; Humans ; Immunohistochemistry ; Keratinocytes/cytology/*metabolism ; Lipopolysaccharides/pharmacology ; Male ; RNA, Messenger/genetics/metabolism ; Research Support, Non-U.S. Gov't ; Reverse Transcriptase Polymerase Chain Reaction ; Skin/cytology/metabolism ; Skin Diseases/*genetics/metabolism/pathology

OBJECTIVETo study the expression of keratinocyte (KC) basement membrane (BM) related genes during the process of re-epithelialization of burn wound in scalded rats with cDNA microarray technique.

METHODSTwenty-four SD rats were inflicted with deep partial thickness scald with an area of 45 cm(2) on the back, and they were randomly divided into A [3 postscald day (PSD)], B (10 PSD), C (14 PSD) and D (re-epithelialization complete day) groups, with 6 rats in each group. Tissue samples were harvested from 1 cm of wound margin on 3, 10 and 14 PSD. On the re-epithelialization complete day, tissue samples were harvested from the center of the wound in D group and digested with enzyme into KC suspensions. Skin samples from the back of 6 uninjured rats were taken as normal control. The differential expression of KC BM related genes during different stages of re-epithelialization was assayed with cDNA microarray.

RESULTSThe expression of laminin (LN) gamma 1 (2.068) and integrin beta8 (2.200) was up-regulated on 3 PSD compared with that in control. The expression of integrin beta1 and LN receptor 1 was up-regulated on 10 and 14 PSD, (2.472 and 2.658), while that of integrin beta2 and beta1 (0.419 and 0.462) down-regulated on 10 and 14 PSD, and the expression of type IV collagen alpha1 and alpha3 was up-regulated during re-epithelialization.

CONCLUSIONThe expression of integrin beta1, LN gamma 1, LN receptor 1, type IV collagen alpha1 and alpha3 genes were up-regulated during re-epithelialization, which might be beneficial to the construction of BM in new skin and the formation of stable conjunction between KC and BM.

Animals ; Basement Membrane ; metabolism ; Burns ; metabolism ; pathology ; Collagen Type IV ; genetics ; Disease Models, Animal ; Epithelium ; metabolism ; Gene Expression ; Integrin beta1 ; genetics ; Integrins ; genetics ; Keratinocytes ; cytology ; metabolism ; Laminin ; genetics ; Oligonucleotide Array Sequence Analysis ; Rats ; Rats, Sprague-Dawley ; Regeneration ; Skin ; cytology ; Wound Healing