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M Thewes

Publications and source records attributed to M Thewes.

At least 19 recordsLinked to original sources
PubMed2001

Immunohistochemical characterization of the perivascular infiltrate cells in tissues adjacent to stainless steel implants compared with titanium implants.

Metallic orthopaedics implants are composed of elements that are known to be skin sensitizers in the general population. In this study, we analyzed the cells of perivascular infiltration in the tissue adjacent to titanium (n = 23) and steel (n = 8) implants after explantation of the metals by immunohistochemical methods. The following panel of monoclonal antibodies were used as parameters: CD 1a (Langerhans cells), CD 4 (T-helper cells), CD 8 (T-suppressor cells), CD 11c (monocytes and macrophages), CD 45 RO (memory cells), CD 45 RA (naive cells), eosinophil cationic proteins (ECP), neutrophil elastase, and HLA-DR. The number of perivascular total cells did not differ significantly. All cells were identified in both metal subgroups, but a statistical difference was not seen in the above-mentioned parameters. We conclude that sensitization to metals is possible in the tissue adjacent to steel and titanium implants, because all cells which play an important role in allergic delayed-type hypersensitivity (type IV) reactions are present. This phenomenon may be called a 'pre-sensitization' phase, because no sensitization or allergic reactions were seen in our cases. Second, in the present study, a statistical difference was not seen in the number of infiltrate cells in the tissue adjacent to steel compared with titanium implants.

Adult↗
PubMed2000

The urokinase plasminogen activator system in angiosarcoma, Kaposi's sarcoma, granuloma pyogenicum, and angioma: an immunohistochemical study.

UNLABELLED: Background Extracellular matrix proteolysis is one of the most important steps in angiogenesis. The urokinase-type plasminogen activator system (uPAS), consisting of the urokinase plasminogen activator (uPA), the uPA receptor (uPA-R), and their corresponding inhibitors, PAI-1 and PAI-2, is thought to play a role in this process. METHODS: We investigated the expression of the components of uPAS in angiosarcoma (AS, n = 4), Kaposi's sarcoma (KS, n = 31), granuloma pyogenicum (GP, n = 25), angioma (AN, n = 15), and healthy controls (CO, n = 15) with immunohistochemical methods. RESULTS: We found positive immunostaining for uPA-R and uPA in all cases of AS. Only two of four cases were positive for PAI-1, whereas all cases were negative for PAI-2. In KS, we observed positive immunostaining in 16 of 31 (51.6%) cases for uPA-R, in 11 of 31 (35.5%) cases for uPA, in 3 of 31 (9.6%) cases for PAI-1, and in 2 of 31 (6.4%) cases for PAI-2. The GP cases showed the following positive results: 4 of 25 (16%) for uPA-R, 6 of 25 (24%) for uPA, 10 of 25 (40%) for PAI-1, and 11 of 25 (44%) for PAI-2. Four cases (26.6%) of AN were positive for PAI-1 and five cases (25%) for PAI-2. In AN (n = 15), there was staining for neither uPA nor uPA-R. In none of the controls (n = 15) was immunostaining for the components of uPAS found in blood vessels. CONCLUSIONS: uPAS is involved in malignant, benign, and reactive proliferative angiomatous lesions, but is absent in normal blood vessels. The upregulation of uPA and its corresponding receptor, uPA-R, in AS and KS supports the hypothesis of the proliferative nature of these lesions; however, the upregulation of the inhibitors (PAI-1 and PAI-2) in benign and reactive proliferative angiomatous lesions (GP and AN) shows how this process may be limited.

Granuloma, Pyogenic↗
PubMed1999

Stromelysin-3 (ST-3): immunohistochemical characterization of the matrix metalloproteinase (MMP)-11 in benign and malignant skin tumours and other skin disorders.

Matrix metalloproteinases (MMP) are involved in remodelling of the extracellular matrix (ECM) proteins suggesting that they play an important role in inflammatory process, in tumour invasion and metastasis. We examined immunohistochemically 330 cases of different skin disorders with the monoclonal antibody against MMP 11, stromelysin-3 (ST-3) protein. We found a positive immunoreactivity in fibroblasts surrounding malignant epithelial tumour cells in 63 of 125 cases (50.4%) of basal cell carcinomas, in four of 25 (16%) squamous cell carcinomas, whereas the tumour cells themselves were negative. Furthermore, the ST-3 protein could be detected in 23 of 40 cases (57.5%) of dermatofibroma, in two of five cases (40%) of atypical fibroxanthoma, in one of eight cases (12.5%) of dermatofibrosarcoma protuberans and, locally, in one of 10 cases (10%) of malignant fibrous histiocytoma. It was not present in the following skin lesions: keratoakanthomas (n = 12), Bowen's disease (n = 10), malignant melanoma (n = 12), melanocytic nevi (n = 28) and Kaposi's sarcomas (n = 25). In eczema (n = 10), psoriasis (n = 10) and virus-induced tissues (i.e. condylomata acuminata, n = 10) we did not observe an expression of ST-3 protein. We conclude first that ST-3 protein is a fibroblastic factor expressed in stromal cells adjacent to carcinoma cells; second, that ST-3 protein seems to be associated with benign fibroblastic tumours; and third, that it does not play a role in eczema, psoriasis or virus-induced skin lesions.

Basal Cell Carcinoma↗
PubMed1999

The clinical expression of allergy in the skin.

The cutaneous immune system has evolved to protect the organism from potential exogenous pathogens in a complex manner. Recent investigations of the special role of the skin in allergy have focused on the proinflammatory potential of various cells such as Langerhans' cells, keratinocytes, mast cells (MC), endothelial cells, and dermal fibroblasts. Furthermore, in processing and reacting to antigens, infiltrating inflammatory cells (lymphocytes; monocytes; macrophages; and eosinophil, neutrophil, and basophil granulocytes) play an important role both by cell-cell interactions with specific receptors on cell surfaces and via soluble mediators.

Antigen Presentation↗
PubMed1998

Stromelysin-3: a potent marker for histopathologic differentiation between desmoplastic trichoepithelioma and morphealike basal cell carcinoma.

Histopathological differentiation between desmoplastic trichoepithelioma (DTE) and morphealike basal cell carcinoma (BCC) is a difficult problem because of their similar morphological features. The matrix metalloproteinase stromelysin-3 (ST-3), which is expressed as a specific fibroblastic factor especially surrounding carcinoma cells, was studied in these both conditions of wholly different clinical outcome. Using formalin-fixed paraffin-embedded tissues, we found positive immunoreactivity for ST-3 in fibroblastic cells surrounding morphealike BCC cells in 34 (68%) of 50 cases, whereas the epithelial tumor cells themselves were negative. In none of the 12 cases of DTE did we observe expression of ST-3 in fibroblasts. We conclude that the antibody against ST-3 protein is an immunohistochemical marker to distinguish morphealike BCC from DTE.

Biomarkers, Tumor↗
PubMed1998

Expression of cathepsins in dermal fibrous tumors: an immunohistochemical study.

Cathepsins are lysosomal proteases that are distributed in many normal tissues and are primarily responsible for intracellular catabolism and turnover. The increased level of cathepsins in tumors together with their ability to degrade extracellular matrix proteins has led to the hypothesis that they are involved in the process of invasion and metastasis. We studied immunohistochemically the expression of cathepsins B, pro-D and pro-L in 8 cases of dermatofibrosarcoma protuberans (DFS), five cases of atypical fibroxanthoma (AFX) and twenty cases of dermatofibroma (DF). Expression of cathepsins B and pro-D could be detected in 5 of the 8 cases (62.5%) of DFS, whereas cathepsin pro-L was found in 4 (50%) cases. All AFX expressed cathepsin pro-L, whereas cathepsins B and pro-D were observed in 4 out of 5 cases. None of the malignant tumors showed a recurrence or metastasis after a period of four years. We found no expression of cathepsins in DF. In the epidermis and appendages, an expression of cathepsins pro-D, pro-L and B was seen. We conclude that cathepsins may be markers of increased metabolism rather than specific markers of malignancy.

Adolescent↗
PubMed1997

Immunohistochemical analysis of procathepsin L and cathepsin B in cutaneous Kaposi's sarcoma.

BACKGROUND: The expression of the proteinases cathepsins L and B are induced in tumors by malignant transformation, growth factors, and tumor promoters suggesting they play an important role in tumor invasion and metastasis. METHODS: By immunohistochemistry, procathepsin L and cathepsin B were studied in patients with Kaposi's sarcoma (KS). Formalin-fixed and paraffin-embedded tissues from 29 cases of KS (AIDS-associated KS, n = 24; non-AIDS-associated KS, n = 5) were immunolabeled with the polyclonal antibody directed against procathepsin L and the antisera directed against cathepsin B. RESULTS: Normal epidermis, eccrine sweat glands, and hair follicle expressed both cathepsins. We also found a positive staining for procathepsin L in normal blood vessels. In both "angiomatous" and "fibroblastic" lesions of KS no expression of these enzymes was observed. CONCLUSIONS: These findings support the hypothesis of a benign autochthonous origin of the lesions, such as a hyperplasia.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Stromelysin-3 (ST-3) mRNA expression in colorectal carcinomas. Localization and clinicopathologic correlations.

Stromelysin-3 (ST-3) mRNA expression was studied in 28 colorectal carcinomas and compared with that of adjacent nontumorous tissue. By Northern blot analysis, levels of ST-3 mRNA were significantly increased in the carcinomas compared with ST-3 expression was seen with degree of invasion, nodal or distant metastases, or histologic grade. In situ hybridization of nontumorous tissue showed no significant ST-3 expression. In tumor tissue, ST-3 mRNA was localized adjacent to colon carcinoma cells in irregular foci within the stoma. No significant difference in ST-3 expression was found between the center and periphery of the colon tumors. Most of the colon carcinomas (26 of 28) induced an expression of ST-3 in the directly adjacent stroma. No significant correlation between ST-3 mRNA expression and tumor stage and grade was seen. By Northern blot, we also saw expression of ST-3 in noncarcinomatous tissue, further supporting the concept that ST-3 expression is a tumor-induced but not a tumor-specific phenomenon.

Adult↗
PubMed1991

Normal psoriatic epidermis expression of hyperproliferation-associated keratins.

Keratin expression in lesional, marginal and uninvolved psoriatic epidermis was analysed by one- and two-dimensional gel electrophoresis and immunoblotting. Keratins K1, K5, K6, K10, K14, and K16 were identified in lesional epidermis. Keratins K6 and K16 were found in all epidermis probes of uninvolved skin, but never occurred in normal epidermis of control skin samples. By means of laser-densitometric evaluation of one-dimensional gels a downregulation of K1 and K10 and an upregulation of K6 and K16 was found in psoriatic epidermis. Unexpectedly, the level of K5 was considerably lower and the level of K14 considerably higher in lesional skin than in normal epidermis. These results demonstrate that not only basal keratinocytes in lesional epidermis but also suprabasal keratinocytes in uninvolved psoriatic epidermis express an altered differentiation pattern. The latter phenomenon could be very important in understanding the development of the so-called "Köbner effect" in psoriatic epidermis.

Adult↗