Comparison of the histological morphology between normal skin and scar tissue / 华中科技大学学报（医学）（英德文版）

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.

Allergens-induced sensitization alters airway epithelial adhesion molecules expression in mice / 生理学报

To explore the relationship between the epithelial adhesion molecules and immune responses of airway epithelium, we observed the expression of integrin β4 and intercellular adhesion molecule-1 (ICAM-1) in the mice airway epithelium after sensitization with allergens. BALB/c mice were sensitized with intraperitoneal injection of ovalbumin (OVA) or house dust mite (HDM) and then developed airway hyper-responsiveness as determined by barometric whole-body plethysmography. Both OVA and HDM sensitization led to increases of the number of peripheral leukocytes as well as inflammatory cells infiltration in lungs. OVA sensitized mice showed more severe inflammatory cells infiltration than HDM sensitized mice. Immunohistochemistry analysis of mice lung tissues revealed that sensitization with both allergens also led to a decrease of integrin β4 expression and an increase of ICAM-1 expression in airway epithelia. OVA sensitized mice showed a more significant increase of ICAM-1 expression compared with HDM sensitized mice. siRNA mediated silencing of integrin β4 gene in 16HBE cells resulted in an up-regulation of ICAM-1 expression. Our results indicate a possible role of airway epithelial adhesion molecules in allergen-induced airway immune responses.

TiO2 nanotube stimulate chondrogenic differentiation of limb mesenchymal cells by modulating focal activity

Vertically aligned, laterally spaced nanoscale titanium nanotubes were grown on a titanium surface by anodization, and the growth of chondroprogenitors on the resulting surfaces was investigated. Surfaces bearing nanotubes of 70 to 100 nm in diameter were found to trigger the morphological transition to a cortical actin pattern and rounded cell shape (both indicative of chondrocytic differentiation), as well as the up-regulation of type II collagen and integrin beta4 protein expression through the down-regulation of Erk activity. Inhibition of Erk signaling reduced stress fiber formation and induced the transition to the cortical actin pattern in cells cultured on 30-nm-diameter nanotubes, which maintained their fibroblastoid morphologies in the absence of Erk inhibition. Collectively, these results indicate that a titanium-based nanotube surface can support chondrocytic functions among chondroprogenitors, and may therefore be useful for future cartilaginous applications.

Application of Confocal Laser Scanning Microscopy to the Differential Diagnosis of Bullous Pemphigoid and Epidermolysis Bullosa Acquisita / 대한피부과학회지

BACKGROUND: The differential diagnosis of bullous pemphigoid (BP) and epidermolysis bullosa acquisita (EBA) presents some difficulties since both diseases have overlapping clinical and histological features, as well as immunopathological findings. Confocal laser scanning microscopy (CLSM) has been developed and has shown to be a promising tool for dermatological investigations, giving a higher degree of resolution and available co-localization analysis. OBJECTIVE: The purpose of this study was to evaluate whether the new technique of CLSM could reliably identify and differentiate the binding sites of disease specific-autoantibodies (Abs) at the basement membrane zone (BMZ), with the sera from BP and EBA. METHODS: An indirect immunofluorescence (IF) assay was performed to localize the binding sites of circulating Abs from 5 cases of both BP and EBA, as well as the sites of 3 BMZ markers (integrin beta4, laminin-5, and type IV collagen). To facilitate identification and topographic differentiation between the two groups, patients' Abs were labeled with fluorescein isothiocyanate, whereas the BMZ markers were labeled with Texas red. The tissue specimens were observed under both conventional IF microscopy and CLSM. RESULTS: Owing to superposition of antigens and marker labels, double immuno-labeled sections under IF microscopy revealed limitations for the differentiation of patient's sera from BMZ markers even with high magnification (x1,000). However, CLSM was able to eliminate much of the antigen overlap. In BP, the circulating autoantibody' deposits were recognized on the epidermal side of laminin-5 and type IV collagen, and codistributed with integrin beta4. On the other hand, the binding of autoantibodies in EBA was on the dermal side from that of integrin beta4, laminin-5 and type IV collagen. These spatial relationships are compatible with their known microstructural locations. CONCLUSION: Our study indicates that CLSM examination may provide more precise localization of the antigens in BP and EBA than conventional IF microscopy. CLSM would not only be an efficient tool to identify circulating anti-BMZ autoantibodies for diagnosis and differential diagnosis of blistering diseases, but also a great addition to examining tissue specimens in patients who do not have detectable circulating Abs.

The Effects of Retinoids on Expression of beta4 Integrin and Growth of the Head and Neck Squamous Cell Carcinoma Cell Lines / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Retinoids have been used in chemoprevention trials for a variety of epithelial malignancies. However, high incidence of toxicity and drug resistance remains as problems. Increase of the retinoid metabolism by cytochrome P450 has been known as one of the several mechanisms explaining these toxicity and the aquired resistance. There have been many studies about the biological effects of retinoids in head and neck squamous cell carcinoma (HNSCC), but there is no information about the effects of the retinoids metabolism on cell biology. The study presented here is designed to examine the relationship between cytochrome P450 induction and responses to retinoids in the HNSCC cell lines. MATERIAL AND METHODS: We used a human HNSCC cell lines (AMC-HN-4, AMC-HN-6). The change of metabolic activity was analyzed using thin layer chromatography (TLC). The effects of retinoids on cell proliferation were evaluated with CellTiter 96 TMAQueous Cell Proliferation Assay. The effects of retinoids on beta4 integrin expression were evaluated with flow cytometry. RESULTS: The inhibitory effects of retinoids on cell proliferation were higher in AMC-HN-4 cell line (cytochrome P450 uninducible) than in AMC-HN-6 cell line (cytochrome P450 inducible) (p<0.05). The expression of beta4 integrin was more effectively suppressed in the AMC-HN-4 cell line than in the AMC-HN-6 cell line. CONCLUSION: The results of this study suggest that cytochrome P450 inducilbility may be an important factor to determine the biological effects of retinoids in HNSCC cells.

Expression of Adhesion Molecules in Placenta and Correlation with Uterine Artery Doppler Velocimetry in Pregnancy-induced Hypertension / 대한산부인과학회잡지

INTRODUCTION: The pathophysiology of PIH remains unclear. Recently, placental abnormalitiesare stressed as a possible cause of PIH. Abnormal shallow invasion of trophoblasts, confinedto decidua, without involving myometrium is believed to result in reduced uteroplacentalperfusion, endothelial injury, and activation of coagulation cascade system. Integrin, one of theadhesive membrane proteins, is expected to be related to the regulation of trophoblasts invasion. PURPOSE: The purpose of this study is to investigate the expression of adhesion moleculesin placenta and the correlation between uterine artery Doppler findings and integrinexpressions in the placentas of PIH patients. SUBJECTS: Thirty-six cases of severe PIH patients were enrolled in the study with 10number of normal control pregnant women. The integrin subunit expressions withimmunohistochemical staining were observed in floating villi, maternal-side cytotropholbasts, andfetal-side cytotrophoblasts. Uterine artery Doppler study was also performed, and the S/Dratio was evaluated. Abnormal Doppler findings was defined as S/D ratio>or=2.6. RESULTS: Cytoplasmic staining of villi and placental bed cytotrophoblast for theintegrin alpha1 subunit in PIH specimen was weaker than those in normal controls. Theexpression of integrin beta1 subunit was negative for both controls and PIH group. Thepositive cytoplasmic stain was observed among PIH placenta in contrast to normal control inwhich the expression of integrin beta4 subunit was not detected. The expression of alpha v beta3 introphoblast with PIH was positive staining, but not in control group. Uterine artery Dopplervelocimetry was performed in 25 cases with PIH. Trace(+/-) or - staining of integrin alpha1 subunit were observed in 60.0% of abnormal S/D(>or=2.6) group, 20.0% of normal S/Dratio group patients, respectively. Trace or + staining of integrin beta4 subunit were observedin 50.0% of abnormal S/D group and 6.7% of normal S/D group and this is in statisticallysignificant. Trace or + staining of integrin alpha v beta3 subunit were observed 70.0% ofabnormal S/D group and 26.7% of normal S/D group, and this statistically significant. CONCLUSION: In PIH the abnormality in the invasion of cytotrophoblats results inabnormal integrin subunit expression, but it is also correlated to the abnormal uterine arteryDoppler velocimetry which shows a S/D ratio of greater than 2.6. Thus, the uterine arteryDoppler velocimetry reflects abnormal placentation.