Monkeypox virus: histologic, immunohistochemical and electron-microscopic findings.

BACKGROUND: Human monkeypox, an emerging viral zoonosis first recognized in Africa, has recently emerged in the mid-western US. Initially, it presents with skin eruptions and fevers with diaphoresis and rigors. Clinically, the skin lesions progress from papules to vesiculopustules to resolving eschars. METHODS: Three cutaneous biopsy specimens from two patients with polymerase chain reaction (PCR)-proven monkeypox were available for review. The histologic, immunohistochemical and electron-microscopic features were identified. RESULTS: The clinical progression of lesions is mirrored histologically with ballooning degeneration of basal keratinocytes and spongiosis of a mildly acanthotic epidermis progressing to full thickness necrosis of a markedly acanthotic epidermis containing few viable keratinocytes. A lichenoid-mixed inflammatory cell infiltrate is present, which exhibits progressive exocytosis with the keratinocyte necrosis. Inflammation of the superficial and deep vascular plexes, eccrine units and follicles is also present. Viral cytopathic effect is manifest by multinucleated syncytial keratinocytes. Immunohistochemically, viral antigen is detected within keratinocytes of the lesional epidermis, follicular and eccrine epithelium and few dermal mononuclear cells. Electron microscopy reveals virions at various stages of assembly within the keratinocyte cytoplasm. CONCLUSIONS: The histologic differential diagnosis includes herpes simplex virus, varicella and other pox viruses, such as smallpox. The first one may be differentiated histologically, immunohistochemically and electron microscopically. The last two may be differentiated using PCR assay for the monkeypox extracellular-envelope virus protein gene.

Carcinoma with thymus-like differentiation arising in the dermis of the head and neck.

Carcinoma exhibiting thymus-like differentiation (CASTLE) is a rare, distinct tumor of the thyroid gland or soft tissue of the head and neck that may simulate primary squamous cell carcinoma or lymphoepithelioma, and which contains features reminiscent of thymic differentiation including Hassall's corpuscles, occasional perivascular spaces, and the presence of lymphocytes. Ectopic thymic tissue may result from incomplete descent or persistence of the cervical portion of the thymus and may occur anywhere along the course of the embryonic descent from the angle of the mandible to the sternal notch. Herein, we report two cases of dermal extrathyroidal CASTLE. The differential diagnosis of squamoid carcinoma with features of thymic differentiation includes extrathyroidal CASTLE, a primary squamous cell carcinoma with thymic differentiation, lymphoepithelioma-like carcinoma of the skin, and metastatic squamous cell carcinoma of unknown primary. It is essential that the latter two be ruled out before accepting the diagnosis of an extrathyroidal carcinoma with thymus-like differentiation.

Leukocytoclastic (small vessel) vasculitis in multiple myeloma.

The hallmark of leukocytoclastic vasculitis (LCV) is palpable purpura. Histologically, there is a neutrophilic, angiocentric, segmental inflammation with endothelial cell injury and fibrinoid necrosis of the blood vessel walls. Leukocytoclastic vasculitis has many associations, including, rarely, multiple myeloma (MM). A total of 2357 patients with a diagnosis of MM were reviewed to retrieve cases that had developed leukocytoclastic vasculitis. Eight patients with MM and LCV showed a predominance of immunoglobulin G (IgG) myeloma paralleling the immunoglobulin secretion seen overall. Overexpression of interleukin 6, which is necessary for myeloma cell growth and survival, may contribute to the pathogenesis of LCV in the setting of MM.

Sweet syndrome in multiple myeloma: a series of six cases.

BACKGROUND: Sweet syndrome (SS), a paraneoplastic syndrome characterized by fever, neutrophilia, multiple erythematous painful plaques, and a dense dermal neutrophilic infiltration, has a known association with hematologic malignancies such as acute myelogenous leukemia. However, no clear association with multiple myeloma (MM) has been reported. MATERIALS AND METHODS: Pathology reports of the 2357 patients with multiple myeloma at the University of Arkansas for Medical Sciences were reviewed to retrieve cases who had developed SS. Cytogenetic studies and immunoglobulin secretory status were retrieved. Five cases of SS in MM and 25 cases of SS in patients without MM underwent syndecan-1 immunohistochemistry. OBSERVATIONS: Six cases of SS occurring in the setting of MM showed a predominance in patients secreting IgG paraprotein. Five of the six patients received granulocyte-colony stimulating factor while the sixth received granulocyte-monocyte-colony stimulating factor. Fifty percent showed a non-specific cytogenetic anomaly. CONCLUSIONS: There is no specific cytogenetic anomaly associated with SS in the setting of MM. This paraneoplastic syndrome may be secondary to elevated levels of granulocyte colony stimulating factor (G-CSF), possibly with a component of enhanced sensitivity to endogenous G-CSF. The immunoglobulin secretory status parallels that seen in MM with cutaneous involvement, but IgG secretors may be at an increased risk of developing SS compared with their counterparts who secrete other immunoglobulins.

AL amyloidosis is not present as an incidental finding in cutaneous biopsies of patients with multiple myeloma.

Multiple myeloma (MM) is a monoclonal B-cell neoplasm characterized by autonomous proliferation of immunoglobulin-secreting plasma cells that are capable of synthesizing amyloidogenic light chains resulting in AL amyloidosis. Clinically occult AL amyloid deposition may occur in up to 31% of patients with MM. The prognosis of combined amyloidosis and MM is improving with new therapeutic options. Thus it is imperative that patients with MM be screened for amyloidosis. Sixty-six consecutive skin biopsies from patients with MM and the diagnosis of graft vs. host disease (GVHD) were stained with Congo red and assessed for the presence of amyloid deposition. Twelve cases that had amyloid deposition in other tissue and had a cutaneous biopsy were also stained with Congo red and assessed for the presence of amyloid deposition. None of the 66 biopsies of GVHD, and none of the 12 cases that had documented amyloid deposition in other tissue showed evidence of amyloid deposition in the cutaneous biopsies. In the absence of specific cutaneous manifestations of amyloidosis, it is unlikely that amyloidogenic light chain deposition in the skin would be found. Type I collagen may appear similar to amyloid, both by light microscopy and fluorescence, after staining with Congo red. Thus care must be taken not to confuse type I collagen autofluorescence with positivity for amyloid when assessing skin biopsies stained with Congo red.

Syndecan-1 (CD138) immunoreactivity in bone marrow biopsies of multiple myeloma: shed syndecan-1 accumulates in fibrotic regions.

Syndecan-1 (CD138) mediates myeloma cell adhesion, and loss of syndecan-1 from the cell surface may contribute to myeloma proliferation and dissemination. Flow cytometry analysis of myeloma cells in bone marrow specimens shows heterogeneity in cell surface syndecan-1 expression. It is not known whether weaker expression correlates with more aggressive disease. However, recent reports suggest that variations in syndecan-1 staining intensity on myeloma cells may be an artifact of specimen handling. In this study, we evaluate syndecan-1 expression in bone marrow biopsy sections from 28 multiple myeloma patients, to elucidate the heterogeneity of syndecan-1 expression in situ. Immunoreactivity for syndecan-1, using the antibody B-B4 (CD138), was found in more than 95% of multiple myeloma cells in 27 of 28 biopsies. However, one biopsy had more than 50% CD138-negative cells and cells with weak CD138 expression were identified in the majority of cases. Loss of syndecan-1 did not appear to relate to myeloma cell differentiation. In addition, syndecan-1 was detected on intravascular and intrasinusoidal myeloma cells suggesting that loss of syndecan-1 may not be required for extramedullary dissemination. Bone marrow biopsies from nine additional patients, with variable CD138 staining intensity on myeloma cells as determined by flow cytometry, were studied by immunohistochemistry. The heterogeneous CD138 expression was confirmed in situ, with weakly positive cells concentrated in areas of reticulin fibrosis. These cells had a disrupted pattern of membrane staining in contrast to the strong linear membrane staining seen in the other multiple myeloma cells. In addition, the fibrotic stroma stained intensely for syndecan-1. Accumulation of syndecan-1 within the extracellular matrix of the marrow likely is derived by shedding of the molecule from the surface of myeloma cells. Because syndecan-1 can act to regulate the activity of heparan-binding growth factors, these reservoirs of syndecan-1 may play a critical role in promoting myeloma pathogenesis, or in regeneration of the tumor after chemotherapy.

Plasma cells in chronic endometritis are easily identified when stained with syndecan-1.

BACKGROUND: Chronic endometritis has been observed in 3-10% of women with irregular uterine bleeding who undergo endometrial biopsy. The diagnosis of chronic endometritis rests on the recognition of plasma cells in endometrial tissue that may show a prominent spindle cell stromal component, and is frequently difficult to date. Syndecan-1 is a cell-surface proteoglycan that is expressed on the cell surface of plasma cells. DESIGN: Eighteen endometrial curettage cases with the diagnosis of chronic endometritis and 25 endometrial curettage cases of dysfunctional uterine bleeding, in females under the age of thirty-five in whom no other histopathologic changes were noted, were reviewed for the presence of plasma cells. Sections were then stained with syndecan-1. RESULTS: All of the chronic endometritis cases showed easily visible syndecan-1 staining of plasma cell membranes. None of the cases of dysfunctional uterine bleeding showed presence of plasma cells in either the hematoxylin and eosin stained or syndecan-1 stained sections. CONCLUSIONS: In cases of suspected chronic endometritis in which no plasma cells can be found on hematoxylin and eosin stained slides, syndecan-1 may be an effective adjunct in the identification of plasma cells and thus aid in the diagnosis of chronic endometritis.

The expression of syndecan-1 is preferentially reduced compared with that of E-cadherin in acantholytic squamous cell carcinoma.

BACKGROUND: Syndecan-1 and E-cadherin are cell adhesion molecules which are expressed primarily on the surface of adult epithelial cells. They appear to be co-regulated and may act in concert to stabilize the epithelium. Loss of expression of both E-cadherin and syndecan-1 is seen in malignant transformation and invasion. METHODS: Thirteen cutaneous biopsies of acantholytic squamous cell carcinoma (SCC) were examined for coexpression of E-cadherin and syndecan-1. RESULTS: Interestingly, immunoreactivity for E-cadherin was increased in the in situ component while immunoreactivity for syndecan-1 was similar to that seen in normal skin. Conversely, in invasive SCC the expression of these two adhesion molecules was very similar. Both diminished with decreasing cell differentiation, as well as in the acantholytic areas where both molecules exhibited increasing cytosolic staining rather than cell membrane staining. CONCLUSIONS: Our results suggest that it is likely E-cadherin and syndecan-1 act in concert to stabilize the epithelium and that the loss or decreased expression of both of these adhesion molecules is associated with malignant transformation.

Acantholysis and spongiosis are associated with loss of syndecan-1 expression.

BACKGROUND: Syndecan-1, a heparan sulfate proteoglycan present on the membrane of keratinocytes, functions in intercellular adhesion. Acantholysis and spongiosis are both characterized by diminished intercellular adhesion that may lead to blister formation. In spongiotic conditions, desmosomal stretching occurs prior to cell separation while in acantholytic conditions, cell separation occurs without stretching. While many of the structural relationships have been described, the molecular interactions regulating keratinocyte to keratinocyte adhesion are not yet fully understood. METHODS: Sections from ten cases of Grover's disease, two pemphigus vulgaris, one pemphigus foliaceus, one bullous pemphigoid, two herpes simplex, and ten spongiotic dermatitis were stained with BB-4, a monoclonal anti-syndecan-1 antibody. RESULTS: Nine of ten Grover's, all three pemphigus, and both herpes cases showed absent or markedly decreased syndecan-1 expression by acantholytic keratinocytes, with a sharp delineation from adjacent unaffected skin. The remaining Grover's case showed moderate loss of syndecan-1 expression. The pemphigus foliaceus case showed retention of staining along the basal cell layer, but expression was lost in the mid stratum spinosum. All ten spongiotic cases showed a diffuse mild decrease in staining, with loss of syndecan-1 expression surrounding microvesicles. Bullous pemphigoid, as expected, did not show loss of syndecan expression. CONCLUSIONS: The loss of syndecan-1 expression evident in acantholytic conditions and, to a lesser extent in spongiotic conditions, may contribute to the decreased intercellular adhesion characteristic of these lesions.

Syndecan-1 expression is decreased with increasing aggressiveness of basal cell carcinoma.

Syndecans, a family of cell-surface proteoglycans of which syndecan-1 is the prototypical member, play an important role in limiting tumor growth and invasive capacity through their actions as receptors for growth factors and extracellular matrix. Cutaneous biopsy specimens of basal cell carcinoma, including superficial, nodular, infiltrative, and morpheic subtypes, were assessed regarding the pattern of syndecan-1 expression. We found that with increasing aggressiveness of basal cell carcinomas, syndecan-1 expression is lost from the surface of the neoplastic cells. However, within the dermis, which is normally devoid of syndecan-1 expression, immunopositivity for syndecan-1 is present in areas adjacent to aggressive tumors. This pattern of staining indicates that syndecan-1 expression is produced by stromal cells rather than being shed by the carcinoma cells into the stroma.

Inhibition of platelet thrombosis using an activated protein C-loaded stent: in vitro and in vivo results.

In high-risk and complicated coronary intervention, the risk of acute closure is unpredictable. Thrombus and platelet deposition at the intervention site may also have further effects on subsequent restenosis. In vivo infusion of activated protein C has previously been shown to achieve potent anticoagulation without any haemostatic side effects. We now evaluated the in vitro and in vivo efficacy of polymer-coated coronary stents loaded with purified rabbit Activated Protein C (APC). By measuring 125I-fibrinogen/fibrin deposition APC-loaded stent-wires were antithrombotic compared to albumin-loaded, inhibited-APC-loaded, plain polymer-coated and stainless steel stent-wires. In a balloon injury rabbit iliac artery model, APC-loaded stents did not occlude (0/14) compared to plain stents (9/15) and BSA-loaded stents (2/4). Relative 111In-labelled platelet deposition showed a similarly significant degree of inhibition. In conclusion, APC-loading could render stents significantly less thrombotic. Whether an effective antithrombogenic stent like this effectively reduces restenosis rates warrants further evaluation.

Androgen receptors: a marker to increase sensitivity for identifying breast cancer in skin metastasis of unknown primary site.

Metastatic lesions to the skin may present a dilemma in the identification of the primary site. Breast carcinoma, metastatic to the skin, that is negative for estrogen receptors (ERs) and/or progesterone receptors (PRs) may be mimicked by a number of other metastatic lesions. In the present study, 16 formalin-fixed and paraffin-embedded infiltrating ductal carcinomas metastatic to the skin, which were ER-/PR-, ER-/PR+, or ER+/PR-; 5 metastatic lesions to the skin from primary lesions other than breast cancer; and 5 eccrine tumors were examined for immunoreactivity to the androgen receptor. The majority of the metastatic breast lesions (82%) exhibited immunopositivity for androgen receptor, whereas the metastatic skin lesions from primary lesions other than breast cancer and the eccrine tumors were immunonegative. Thus, androgen receptor immunohistochemistry could serve as a marker to increase sensitivity for identifying breast cancer in skin metastasis of unknown primary sites.

Syndecan-1 expression is diminished in acantholytic cutaneous squamous cell carcinoma.

Syndecan-1 is a cell surface proteoglycan predominantly expressed on the surface of adult epithelial cells, and is normally present in all epidermal layers except for the most superficial terminally differentiated cells. Syndecan-1 mediates cell-cell and cell-extracellular matrix adhesion, thereby influencing cell morphology and growth characteristics. In addition, in vitro studies have shown that expression of syndecan-1 on tumor cells inhibits their invasion into the extracellular matrix. A total of 23 cutaneous biopsies of squamous cell carcinoma, including acantholytic squamous cell carcinoma, invasive squamous cell carcinoma which was not acantholytic, and squamous cell carcinoma in situ were examined for syndecan-1 immunoreactivity. The level of syndecan-1 expression was related to the degree of squamous cell dyshesion, with expression being greatest in the in situ lesions and least in the acantholytic lesions. The loss of syndecan-1 expression with increasing dyshesion of squamous cell carcinoma may be a mechanism for loosening of intercellular and cell-extracellular matrix attachments, thereby promoting the invasion of neoplastic cells into the dermis.

Immunohistochemical staining for androgen receptors: a sensitive marker of sebaceous differentiation.

Androgen receptors (AR) are present in normal skin being localized to the basal and differentiating cells of the sebaceous gland, and as such, sebaceous glands are androgen sensitive tissue. Androgen receptor expression was examined in 43 sebaceous neoplasms including 8 sebaceous carcinomas, 22 sebaceous adenomas, 12 specimens showing sebaceous hyperplasia, and 1 sebaceous epithelioma, as well as in 14 squamous cell carcinomas, 2 clear cell acanthomas, and 35 basal cell carcinomas. Epithelial membrane antigen (EMA) expression was also examined in all of the sebaceous neoplasms. All specimens were fixed in formalin and embedded in paraffin. Diffuse positive nuclear androgen receptor antibody immunohistochemical staining was observed in all samples of sebaceous neoplasms, whereas approximately 60% of basal cell carcinomas showed only focal positivity for nuclear androgen receptor immunoreactivity. Clear cell acanthomas and squamous cell carcinomas were uniformly negative. Whereas all sebaceous neoplasms exhibited immunoreactivity for androgen receptors, the staining pattern was more marked in the nuclei of seboblasts and differentiating sebocytes in the adenomatous, hyperplastic, and epitheliomatous lesions than in the nuclei of the less differentiated sebaceous carcinoma cells. All the sebaceous neoplasms except for sebaceous carcinomas exhibited immunoreactivity for EMA. In the sebaceous carcinomas, EMA staining was absent in the most poorly differentiated specimen, but with increasing differentiation, the carcinomas became immunoreactive to EMA. We have shown that the nuclei of sebaceous neoplasms, including sebaceous gland carcinomas, show immunoreactivity for androgen receptors (AR), that immunohistochemical staining for the presence of AR may be a reliable marker of sebaceous differentiation, and that the AR may be a better marker of sebaceous differentiation than EMA, particularly in poorly differentiated sebaceous carcinomas.

Vascular endothelial growth factor expression in malignant melanoma: prognostic versus diagnostic usefulness.

Vascular endothelial growth factor (VEGF), an endothelial cell mitogen, plays a role in angiogenesis and progression in malignant melanoma. VEGF expression was examined in 62 biopsy specimens of melanocytic proliferations, including 45 malignant melanomas, 3 cellular blue nevi, 12 atypical compound nevi, and 2 Spitz nevi. The cases of malignant melanoma included 11 in situ melanomas, 18 Clark Level II, 9 Clark Level III, and 7 Clark Level IV tissue samples. All of the specimens were fixed in formalin and embedded in paraffin. Cytoplasmic immunoreactivity for VEGF was demonstrated in 19 (42%) of 45 melanoma samples, but there was no immunoreactivity for VEGF exhibited by any of the atypical compound melanocytic nevi, cellular blue nevi, or Spitz nevi (P < .009). Immunoreactivity for VEGF was found to be related to tumor thickness (as evidenced by Clark level [P < .03]) and to absence of regression (P < .04). Although VEGF is not a useful prognostic indicator for malignant melanoma, it may be useful as a discriminating factor between malignant melanoma and benign melanocytic lesions, and it may offer some insight into tumor growth.

Immunohistochemical evaluation of androgen receptors in genital and extragenital lichen sclerosus: evidence for loss of androgen receptors in lesional epidermis.

BACKGROUND: Reduction of lichen sclerosus has been seen with topical testosterone, and spontaneous resolution has been attributed to increasing androgen levels. OBJECTIVE: Our purpose was to investigate the role of androgens in lichen sclerosus by studying lesional skin and site-specific normal skin for the presence of androgen receptors. METHODS: Immunoperoxidase staining for androgen receptors was performed on lesional tissue from 31 patients and microscopically compared with site-specific normal skin. RESULTS: Androgen receptors were present in normal genital and extragenital skin. Lesional genital and extragenital areas showed decreased staining compared with site-specific controls. Finally staining was decreased in histologically well-developed lesions compared with early lesions. CONCLUSION: This study provides evidence for the loss of androgen receptors with disease progression in both genital and extragenital skin affected by lichen sclerosus. These findings support a hormonal pathogenesis of lichen sclerosus and may be significant in the treatment of the disease.

Prediction and diagnosis of attachment loss by enhanced chemiluminescent assay of crevicular fluid alkaline phosphatase levels.

The current study aimed to apply a novel enhanced chemiluminescence assay in the analysis of gingival crevicular fluid (GCF) alkaline phosphatase (ALP) levels from patients with untreated adult periodontitis. 3666 sites in 25 patients were monitored prior to and after attachment loss was detected with a Florida disc probe. Parameters assessed were, relative attachment level, probing pocket depth, occurrence of bleeding on probing (single episode), GCF volume (microliter), total ALP levels (microIU/30 s sample time) and ALP concentration (IU/l). After recruiting patients to the study, all measures were taken at baseline and 3 months later, prior to the institution of non-surgical periodontal therapy at active sites. Thresholds for determining attachment loss were calculated using a modification of the tolerance method. The mesio-buccal sites of all teeth had GCF samples collected. The size of individual patient thresholds used to define whether attachment loss had occurred, was dependent upon the discomfort felt by that patient during electronic probing, with a positive correlation existing between discomfort on probing (10 cm visual analogue scale) and threshold size (R = 0.52, p < 0.049). A total of 274 sites (7.5%) experienced attachment loss of which 39 sites had GCF samples available for analysis. Total ALP levels were significantly higher at baseline for sites that progressed to attachment loss than paired controls (p < 0.003), but all other parameters showed no differences (p > 0.1). There were significant increases in total ALP levels and GCF volumes for active sites between baseline and 3 month measures (p < 0.01), but not for control sites or test site ALP concentration (p > 0.8). The diagnostic accuracy for GCF ALP as a predictor of future attachment loss (threshold 900 microIU/30 s) was 64%, with +ve and -ve predictive values of 62% and 68%. When a threshold of 1300 microIU/30 s was selected for ALP as a marker of recent or currently active disease, diagnostic accuracy and +ve/-ve predictive values were 77% and 77%/76%, respectively. These results indicate that total GCF ALP levels may serve as a predictor of future or current disease activity.

Production of biologically active salmon calcitonin in the milk of transgenic rabbits.

Salmon calcitonin (sCT) is an example of one of the many bioactive peptides that require amidation of the carboxy terminus for full potency. We describe a method for the production of amidated sCT in the mammary gland of transgenic rabbits. Expression of a fusion protein comprising human alpha lactalbumin joined by an enterokinase cleavable linker to sCT was directed to the mammary gland under the control of the ovine beta lactoglobulin promoter. C-terminal amidation in vivo was achieved by extending the sCT by a single glycine residue that provides a substrate for endogenous amidating activity in the mammary gland. Full characterization of the released sCT demonstrated it to be equivalent to synthetic standard in terms of structure, purity, and potency.

Enhanced chemiluminescent assay for measuring the total antioxidant capacity of serum, saliva and crevicular fluid.

This paper reports the development of an enhanced chemiluminescent (ECL) assay for measuring the total antioxidant (AO) capacity of serum, saliva and a fluid collectable from the gum margin called gingival crevicular fluid (GCF). The theory behind the assay is explained, and the optimum conditions for the assay, and for storage of reagents and clinical samples is described. Calibration lines were linear (R > or = 0.99; P < 0.0001) and the within batch coefficient of variations for a water soluble vitamin E analogue (Trolox), serum and saliva samples were < 5%. In saliva and GCF, a characteristic AO response not seen in serum of the same patients, was identified. Total peripheral (serum) and local (saliva) AO capacities (mumol/L Trolox) were investigated in patients with (n = 18) and without (n = 16) adult periodontitis. Serum AO status did not differ between groups. Salivary total AO concentrations were lower in the peridontitis (P) group [175 (53) mumol/L] than in the non-periodontitis (NP) group [254 (110) mumol/L1: P < 0.01], as were saliva:serum AO ratio's [0.37 (0.11) versus 0.5 (0.18): P < 0.01]. Periodontitis patients may have a reduced salivary AO concentration, which could result from, or predispose to, the damaging effects of reactive oxygen species (ROS). The potential for ROS production in the oral and periodontal environment may explain the presence of a specific antioxidant in oral fluids that is not detectable in serum. The ECL assay described provides a rapid, simple and reproducible method of measuring total antioxidant defence in small volumes of biological fluids.