Inflammatory mediators in normal, sensitive and diseased skin types

The role of inflammatory mediators in the pathogenesis and pathophysiology of skin diseases is now widely accepted. We analysed the profiles of inflammatory mediators in normal, sensitive (past history of eczema, but currently patch test negative) and diseased (psoriasis and eczema) skin types to identify the patterns associated with various degrees of inflammatory dermatoses. Compared with normal skin, prostaglandin E2 was increased approximately 3.8-fold (p<0.0002) and 4.7-fold (p<0.0001) in suction blister fluids from sensitive and diseased skin types, respectively. Leukotriene B4 and interleukin-1alpha showed no differences between normal and sensitive skin types. However, in lesional skin from psoriasis and eczema patients, leukotriene B4 was increased approximately 6.6-fold (p<0.0001), whereas interleukin-1alpha was decreased approximately 3.1-fold (p<0.001). Interleukin 6 and tumour necrosis factor-alpha could not discriminate between skin types. We conclude that only prostaglandin E2 showed a significant stepwise increase on progression from normal through sensitive and inflammatory skin diseases. Levels of leukotriene B4 and interleukin-1alpha were also indicative of disease state and may be important in the pathophysiology of these conditions.     

Elastic fibres in normal and sun-damaged skin: an immunohistochemical study

Sun-exposed and sun-protected skin obtained at post mortem from the nape of the neck in 14 subjects was immunostained using antisera to elastin, lysozyme, amyloid P component, and the plasma protease inhibitors alpha-I antitrypsin, alpha-I antichymotrypsin and alpha-2 macroglobulin. Both the normal elastic fibres in sun-protected skin, and elastosis in sun-exposed skin were positively immunostained for elastin, lysozyme and amyloid P component. Collagen fibres were unstained. No immunostaining of normal elastic fibres or elastosis in the skin was obtained with antisera to alpha-I antitrypsin, alpha-I antichymotrypsin or alpha-2 macroglobulin. It was concluded that the elastosis in sun-exposed skin does contain elastic fibres. The absence of immunostaining for plasma protease inhibitors probably indicates that the elastic material is mature, and not newly-formed.     

Ultrastructural morphometric analysis of human mast cells in normal skin and pathological cutaneous lesions

Electron micrographs of human mast cells in normal neonatal and adult skin and in cutaneous lesions of basal cell carcinoma (BCC), hemangioma and mastocytosis were assessed by morphometric analysis. Using this quantitative histologic approach, adult skin mast cells were found to be significantly larger (47.7 microns 2 +/- 2.4 SEM vs. 38.3 microns 2 +/- 1.8 SEM, p less than or equal to 0.001) and have larger granules (0.63 micron +/- .02 SEM vs. 0.53 micron +/- .02 SEM, p less than or equal to 0.001) than infant mast cells while both mast cell populations had comparable nuclear sizes (13.7 microns 2 +/- 0.9 SEM vs. 14.3 microns 2 +/- 0.8 SEM) and numbers of cytoplasmic granules (72 +/- 4.0 SEM vs. 66 +/- 4.0 SEM). Morphometric analysis of mast cell infiltrates in the adult skin lesions of BCC and hemangioma revealed that these cells were larger than neonatal mast cells but were similar to normal adult controls. Cutaneous mast cells from 2 mastocytosis patients, however, had significantly larger mean cell surface areas (78.0 microns 2 +/- 3.4 SEM and 70.6 microns 2 +/- 3.2 SEM, p less than or equal to 0.001), nuclear areas (20.8 microns 2 +/- 1.1 SEM and 21.3 microns 2 +/- 1.2 SEM p less than or equal to 0.001) and granule diameters (0.82 micron +/- 0.4 SEM and 0.83 micron +/- .03 SEM, p less than or equal to 0.001) when compared with mast cells in normal adult skin and in the other pathologic lesions. No difference in the total number of cytoplasmic granules was observed in the different mast cell populations.(ABSTRACT TRUNCATED AT 250 WORDS)     

An immunohistochemical study on cell differentiation in the outer root sheath of the normal human anagen hair follicles with antikeratin monoclonal antibodies]

The expressions of several cytokeratins (CKs) in the outer root sheath (ORS) of the human anagen hair follicles were immunohistochemically studied using 11 antikeratin monoclonal antibodies (MoAbs) and 10 specimens from scalp. CKs 1, 10, 11, which are markers for differentiating keratinocytes, were exclusively found in the intermediate cells and the granular cells at the infundibulum. In cytokeratin expression, a distinct linear demarcation between the infundibulum and the isthmus was observed. Trichilemmal keratinization appeared to go in an inner-upward direction toward the hair canal. CK 19, a marker of undifferentiated stem cells, was found in outermost cells of the ORS at the isthmus and in some cells of the lower ORS. CK 16, a marker of hyperproliferative keratin, was detected in the outermost cells of the infundibulum and all the cells of the ORS below the isthmus. Therefore, the keratinocytes at the infundibulum may show a differentiation similar to that of the interfollicular epidermal keratinocytes. The ORS cells below the isthmus seem to move up to inner-upward direction along the hair axis with differentiation.     

Giant cell fibroblastoma: an immunohistochemical study

Giant cell fibroblastoma is a rare, benign soft tissue tumor occurring in childhood. A 34-year-old woman presented with a giant cell fibroblastoma involving the chest wall. Histologic features include an infiltrating spindle-cell tumor involving the dermis and subcutaneous fat containing characteristic sinusoidal spaces rimmed by spindle cells and multinucleate giant cells. Immunohistochemical studies support a fibrohistiocytic differentiation.     

An immunohistochemical study of laminin in basal cell carcinoma

Background: Laminins are components of the extracellular matrix that mediate cell adhesion, growth, migration, proliferation and differentiation. Basement membrane (BM) laminins, in particular, may play a role in enhancing carcinoma cell motility.
Aim: To evaluate the distribution pattern of laminin in basal cell carcinoma (BCC), as regards the basement membrane, cellular cytoplasm, peritumoral lacunae and surface epithelium and to correlate laminin distribution with different variants of BCC.
Patients and Methods: Skin biopsy specimens were obtained from 21 BCC patients for routine histopathological and immunohistochemical study. Laminin was evaluated qualitatively and semiquantitatively using monoclonal mouse antihuman antibody (Dako-Laminin, 4C7. Code No: MO638, which reacts with the terminal globular domain of the α5 chain)
Results: The majority of BCC cases showed patchy cytoplasmic distribution of laminin. The BM expression of laminin, in most cases, was well defined, fine and linear with irregular areas of thickening. Staining intensity was moderate in differentiated and mixed variants, weak in superficial spreading and absent in morpheic types.
Conclusion: Cytoplasmic and basement membrane laminin is important in the pathogenesis and invasion of BCC. Most laminin was in basement membrane zone (BMZ), and the more differentiated the tumor, the more cytoplasmic and BM staining it expressed.     

An assessment of human epidermal repair in elderly normal subjects using immunohistochemical methods

The purpose of this study was to document a timetable for selected events of epidermal repair in standard partial thickness incised wounds on the legs of normal elderly human subjects. A Simplate-II bleeding-time device was used for producing the wounds, and immunohistochemical techniques were employed for evaluation of the wounds. Antibodies to filaggrin and Ulex europeus I demonstrated little or no staining on migrating epithelium, but staining was apparent whenever epidermal closure had occurred. Bullous pemphigoid antigen was present in the basement membrane zone at all time points examined, including beneath migrating epithelium, whereas antibodies to laminin and type IV collagen were found only at the most lateral aspects of 2-, 3-, and 5-day wounds. Staining progressed centrally by day 7 and was present as a complete linear band beneath most 14-day wounds. The Simplate-II device provides a standard, easy to use, commercially available, sterile, relatively safe method of producing wounds for systematic studies in humans.     

An immunohistochemical study of basal cell carcinoma and trichoepithelioma.

The histologic distinction between tricheopithelioma and basal cell carcinoma may be difficult in small biopsies. Immunohistochemical stains have been used to help make this distinction; however, published studies have generally been limited to a few antibodies. To this end we performed a comprehensive immunohistochemical analysis of 20 basal cell carcinomas and 10 tricheopitheliomas from our files, in search of a consistent pattern of reactivity to distinguish the neoplasms in biopsies. The antibodies used were: low molecular weight keratin (Cam 5.2), Cytokeratin 7, (CK7), Cytokeratin 20, (CK20), Carcino-embryonic antigen (CEA), CD30 (Ki-1), bcl-2, Ham 56, HPCA-I (CD34), and Ulex Europaeus type I. In our study, bcl-2 stained all but one basal cell carcinoma in a diffuse pattern, whereas all tricheopitheliomas showed staining of the outermost epithelial layer. No other stain proved to be an independent marker for either neoplasm and no consistent immunohistochemical profile for either neoplasm emerged. Thus, we conclude that bcl-2 may be of some value in distinguishing basal cell carcinoma from tricheopithelioma, limited by the quantitative nature of the difference in staining. Histologic criteria applied to H&E-stained sections remain the cornerstone of histologic diagnosis.     

Neuroendocrine differentiation in basal cell carcinoma. An immunohistochemical study

Neuroendocrine differentiation in basal cell carcinoma (BCC) of the skin has been reported in the past on the basis of ultrastructural findings, argyrophilia, and the immunohistochemical detection of neuropeptides in such neoplasms. To assess further the relative frequency of neuroendocrine differentiation in BCC, paraffin sections of 53 randomly chosen cases were evaluated for Churukian-Schenk stain positivity and the expression of sensitive neuroendocrine markers. These included neuron-specific enolase (using a highly absorbed monospecific antiserum), chromogranin-A, synaptophysin, neurofilament protein, and Leu-7 antigen. Although 25% of cases demonstrated argyrophilia with the Churukian-Schenk method, suggesting a high frequency of possible neuroendocrine differentiation, immunohistochemical evidence of the same was observed in only two tumors (4%). These demonstrated immunoreactivity for chromogranin and neuron-specific enolase. The results of this analysis suggest that neuroendocrine differentiation in BCC is relatively uncommon, and that it is not reliably predicted by the results of argyrophil stains done on paraffin sections.     

Clear cell syringoid carcinoma: an ultrastructural and immunohistochemical study

Syringoid carcinoma (syringoid "eccrine" carcinoma or eccrine epithelioma) is a rare cutaneous tumor with some controversy regarding its correct definition. It may also be difficult to differentiate from its benign counterpart (syringoma), other adnexal carcinomas, and cutaneous metastasis from adenocarcinomas. We present a case of a syringoid carcinoma of the clear cell variant complemented with an immunohistochemical and ultrastructural study, the latter revealing cytoplasmic accumulation of glycogen and presence of intercellular and intracellular lumina in clear tumor cells, as well as diverse hallmarks of malignancy (i.e., perineural invasion, tumor necrosis, and deep invasion). Clear tumor cells showed cytoplasmic and membranous immunoreactivity to epithelial membrane antigen, carcinoembryonic antigen, keratins, and S-100. Our ultrastructural and immunohistochemical results support the ductal differentiation of the glycogen-filled clear cell tumor population.     

Hyaluronectin in normal human skin and in basal cell carcinoma

The localization of hyaluronectin has been studied in normal skin and in basal cell carcinoma. In fetal skin it is abundant in the dermis but absent from the epidermis, and in adult skin it is totally absent except in the hair sheaths and bulbs. In basal cell carcinoma it is abundant only in the stroma reaction. The presence of this protein in mesenchymatous tissues seems to be linked to zones of physiological or neoplastic proliferation.     

Effect of smoking on skin elastic fibres: morphometric and immunohistochemical analysis

BACKGROUND: It has been established during recent years that smoking is an independent risk factor for the development of premature facial wrinkling. The underlying mechanism is not well known, but elastic fibres of the dermis seem to be the major target of smoke components. OBJECTIVES: To determine quantitative and qualitative changes of the dermal elastic tissue of non-sun-exposed skin induced by smoking, as well as the possible mechanisms responsible for them. METHODS: Sixty-nine patients were recruited (20 nonsmokers, 19 former smokers and 30 smokers). Using static morphometry and immunohistochemistry and lectin staining we analysed elastic fibres of the dermis and their major components, elastin and microfibrillar component. RESULTS: Significantly higher values for the number of elastic fibres mm(-2) and the percentage of the area filled by them in the reticular dermis were found in smokers. Cumulative tobacco dose showed statistically significant correlations with both morphological parameters (Spearman's rank correlation coefficient). Immunohistochemistry demonstrated that the two main components of elastic fibres were altered in smokers. Plasma protease inhibitors and lectin staining were negative in all the samples. CONCLUSIONS: Smoking is an independent risk factor for the increase of elastic fibres in the reticular dermis of nonexposed skin, and it acts on their two main structural components, elastin and microfibrillar component. This increase in the area of elastic fibres in smokers is not due to newly synthesized elastic material, but to their degradation, as occurs in solar elastosis and which acts in an additive manner.     

Desmosome formation in normal human epidermal cell culture

Keratinocytes were dissociated from normal human adult epidermis with clostridial collagenase, dithio-erythritol and trypsin, and cultured. Immediately after this, no connection was seen between contiguous cells. Ruptured desmosomes, with masses of tonofilaments and distinct attachment plaques were still left on the cell surface. As culture proceeded, however, they became internalized into cytoplasm. As soon as culture was started and the cells established contact with each other, forming conglomerates, they began to form desmosomes. The cell membranes of a limited area which were in contact with neighbouring cells became thicker and formed attachment plaques. In the intercellular space of the desmosomal portion, fine filaments developed and a midline formed. The progress of desmosome formation was classified into six types.     

A comparative immunohistochemical study of adult T cell leukemia and cutaneous T cell lymphoma

An immunoperoxidase study of 2 cases of adult T cell leukemia (ATL) and 2 cases of mycosis fungoides (MF) was done using monoclonal antibodies. In ATL, many anti-interleukin-2 receptor antibody (LeuIL-2R)-positive cells were seen in the dermis and occasionally in the epidermis. In contrast, in MF, LeuIL-2R-positive cells were much less frequent. LeuIL-2R-positive cells in MF may be non-malignant T cells; not all LeuIL-2R-positive cells may be malignant in ATL. These non-malignant LeuIL-2R-positive cells, we suggest, are involved in the interaction between malignant T cells and reactive infiltrating cells. Furthermore, in addition to OKT6-positive cells, OKM1-positive cells were seen in the infiltrates in the dermis in both ATL and MF. OKM1-positive cells also participate in the mechanism of the skin affinity in ATL and cutaneous T cell lymphomas.     

Superoxide dismutase in psoriasis, squamous cell carcinoma and basal cell epithelioma: an immunohistochemical study

Monoclonal antibodies against human Cu,Zn-superoxide dismutase (SOD) and Mn-SOD were used to stain frozen sections of normal and abnormal human skin. In normal human epidermis, the Cu,Zn-SOD antibody almost exclusively stained the basal cells. Mn-SOD antibody weakly stained the whole of the epidermis but more predominantly the basal cell layer. In psoriasis, Cu,Zn-SOD antibody mainly stained the basal cells of the lowest parts of the elongated rete ridges. Basal cells corresponding to the tip of the dermal papillae were weakly stained. Mn-SOD staining was considerably decreased in the psoriatic epidermis. In squamous cell carcinoma, staining with both Cu,Zn-SOD and Mn-SOD antibodies was decreased, and single cells positive for Cu,Zn-SOD were scattered throughout the tumour nests. In basal cell epithelioma, Cu,Zn-SOD staining was intense and diffusely distributed throughout the tumour nests, while Mn-SOD staining was absent.     

Multinucleate cell angiohistiocytoma: a clinicopathological, immunohistochemical and ultrastructural study

The term 'multinucleate cell angiohistiocytoma' was first introduced by Smith and Wilson Jones in 1985. We report the clinicopathological, immunohistological and ultrastructural findings observed in two patients. Multinucleate cell angiohistiocytoma occurs mainly in middle-aged women and is usually located at acral sites, particularly the distal extremities. Grouped, brown-red, slightly elevated, asymptomatic papules slowly develop over several months until further growth ceases. There is no evidence of systemic disease. Histologically, the dermis shows numerous well developed capillaries with prominent endothelia, large bizarre basophilic and often multinucleate cells with a sparse lymphohistiocytic infiltrate. The immunohistological and ultrastructural findings suggest a fibroblastic differentiation of the large multinucleate cells.     

Neuroendocrine differentiation in basal cell carcinomas: a retrospective immunohistochemical and ultrastructural study

Recent investigations have suggested that in addition to basaloid cells, basal cell carcinomas (BCC) may also contain Langerhans cells and neuroendocrine cells. In order to establish the relative frequency of neuroendocrine differentiation in BCC, we performed a retrospective study of 50 consecutive BCC using conventional histochemical, immunocytochemical and ultrastructural methods. Argyrophil staining according to Grimelius was used for initial identification. Tumors containing argyrophil cells, as well as randomly selected tumors without these cells, were immunocytochemically stained with a panel of antisera against neurohormonal peptides. Only 2 tumors with argyrophil cells showed occasional somatostatin immunoreactivity; peptide hormone immunoreactivity could not be detected in any of the others. The somatostatin immunoreactive tumors, as well as 3 others, were subjected to electronmicroscopy to study the presence of dense-core secretory granules. However, these characteristic intracytoplasmatic structures could be detected in none. It is concluded that if neuroendocrine differentiation exists at all in BCC, it must be extremely rare. Our results indicate that reliable identification of multiple lines of differentiation in neoplasms can only be performed using combinations of (immuno) histochemical and ultrastructural techniques.     

Diversity of human papillomavirus types in periungual squamous cell carcinoma

Background There is accumulating evidence that infections with certain high‐risk α‐human papillomaviruses (HPVs) are involved in the pathogenesis of digital squamous cell carcinomas (SCCs) and their precursor lesions (SCCs in situ). Objectives This study was initiated to search for α‐ and β‐HPV infections in a collective of SCC and SCC in situ located on the hands. Methods HPV typing for 36 high‐risk and low‐risk α‐HPV types and 25 β‐HPV types was performed in SCCs located at different sites of the hands. Additionally, immunohistochemical staining for p16^INK4a and Ki67 was performed in 15 samples. Results In total, 25 SCCs/SCCs in situ (six periungual lesions, eight lesions from the proximal or lateral part of the finger, and 11 lesions from the dorsal part of the hand) were analysed for the presence of α‐ and β‐HPV types. Only one lesion (an SCC in situ positive for HPV11 and HPV31) of the dorsal hand and none of the proximal or lateral part finger lesions were α‐HPV positive. In contrast, all six periungual lesions were α‐HPV positive, and the majority (83%) of them carried HPV types other than HPV16 (HPV26, HPV33, HPV51, HPV56 and HPV73). β‐HPV types were found in only two biopsies. p16^INK4a and Ki67 expression was significantly higher in HPV‐positive lesions as compared with HPV‐negative tumours, and both markers significantly correlated with each other. Conclusions In contrast to other locations of the hands, periungual SCCs are frequently associated with α‐HPV infections. Several high‐risk HPV types other than HPV16 can induce periungual SCCs. Given the high recurrence rate and high proliferative activity of HPV‐associated periungual SCCs, aggressive treatment and close follow‐up of these tumours is mandatory.