Expression of nestin, mesothelin and epithelial membrane antigen (EMA) in developing and adult human meninges and meningiomas

The spatial and temporal pattern of appearance of nestin, epithelial membrane antigen (EMA) and mesothelin proteins was immunohistochemically determined in the cells of normal developing and adult human meninges and meningiomas. Human meninges developed as two mesenchymal condensations in the head region. The simple squamous epithelium on the surface of leptomeninges developed during mesenchymal to epithelial transformation. Nestin appeared for the first time in week 7, EMA in week 8, while mesothelin appeared in week 22 of development. In the late fetal period and after birth, nestin expression decreased, whereas expression of EMA and mesothelin increased. EMA appeared in all surface epithelial cells and nodules, while mesothelin was found only in some of them. In adult meninges, all three proteins were predominantly localized in the surface epithelium and meningeal nodules. In meningothelial meningiomas (WHO grade I), EMA was detected in all tumor cells except in the endothelial cells, mesothelin characterized nests of tumor cells, while nestin was found predominantly in the walls of blood vessels. The distribution pattern of those proteins in normal meningeal and tumor cells indicates that nestin might characterize immature cells, while EMA and mesothelin appeared in maturing epithelial cells. Neoplastic transformation of these specific cell lineages contributes to the cell population in meningiomas.     

Similarities of antisera to casein and epithelial membrane antigen

Summary Antisera raised against human milk fat globule membranes and against the casein fraction of human milk have been compared. Using an immunohistochemical stain of tissue sections it has been shown that many of the antigenic determinants detected by the different antisera are identical. A radioimmunoassay for epithelial membrane antigen (EMA) showed that casein preparations are associated with small quantities of EMA. Antisera to casein frequently contained appreciable concentrations of antibodies to EMA and this accounts for the immunohistochemical staining of non-mammary tissues.     

Distribution of epithelial membrane antigen in benign and malignant lesions of the salivary glands

Summary An antiserum against epithelial membrane antigen has been used to stain a variety of lesions arising in the salivary glands. In normal major and minor glands staining was localised to the ductal systems. There was no evidence of myoepithelial cell staining. The mucous elements of the submandibular and sublingual glands were negative, but in the mucous elements of the minor glands there was focal cytoplasmic positivity. There was no cytoplasmic staining of serous elements in major or minor salivary glands. In pleomorphic adenomas the luminal membrane of ductal elements was strongly positive, with focal cytoplasmic positivity in some myxoid areas. In mucoepidermoid tumours both adjacent cell membranes and cytoplasm were strongly positive. The ductal structure of adenoid cystic carcinomas were clearly delineated while the pseudoducts produced by enclosed areas of stroma were negative. All mesenchymally derived tumours were negative and a tumour previously considered as a chondroma was strongly positive. The results are discussed in relation to phenotypic heterogeneity and the histogenesis of salivary gland tumours.     

Epithelial markers in primary skin cancer: an immunoperoxidase study of the distribution of epithelial membrane antigen (EMA) and carcinoembryonic antigen (CEA) in 65 primary skin carcinomas

Sixty-five primary malignant skin tumours have been stained for carcinoembryonic antigen (CEA) and epithelial membrane antigen (EMA) using rabbit polyclonal affinity-purified antibodies and an indirect immunoperoxidase technique. The tumours consisted of 15 invasive squamous carcinomas, 23 basal cell carcinomas, 16 malignant eccrine poromas (porocarcinomas), and 11 sebaceous carcinomas. The basal cell carcinomas were negative for CEA and EMA except where there was keratotic or sebaceous differentiation. All the sebaceous and squamous carcinomas and 15/16 porocarcinomas contained EMA. 12/15 squamous carcinomas were positive for CEA. The malignant poromas were negative for CEA except on the ulcerated surface of two. In tumours classified as sebaceous carcinomas there was positive staining for CEA in some cells, cyst contents and/or keratotic foci. These findings have implications for the use of immunoperoxidase localization of epithelial markers in the differential diagnosis of primary and metastatic skin cancer.     

Presence of apocrine epithelial antigen (AEA) in type II pneumocytes and in hyaline membranes of neonatal RDS

We have investigated the distribution of an apocrine membrane antigen (AEA) in pulmonary tissue using a rabbit antiserum raised against fat globule glycoproteins isolated from human milk. In indirect immunostaining (PAP, IF) of sections from normal lung tissue, the membranes facing the alveolar lumen of cells corresponding to the type II pneumocytes in the alveolar walls were decorated. The selective distribution of AEA to the membranes of type II pneumocytes was confirmed in double immunostaining by identification of these cells with rat antibodies against surfactant apoprotein. In fetal lung tissue, the AEA antigen was detected by the 9th week of gestation. In lung samples from newborns which had died of respiratory distress syndrome (RDS) the intra-alveolar hyaline membranes stained for the AEA antigen. SDS-PAGE of the immunoprecipitate obtained with anti-AEA serum from radiolabelled glycoprotein fraction of normal lung tissue revealed a single band of 79,000 dalton apparent molecular weight. These findings indicate that the AEA constitutes a membrane marker of the type II pneumocytes and might be involved in the secretory process of surfactant. Immunohistological evidence for the presence of AEA in the hyaline membranes of neonatal RDS is also presented.     

成人侧脑室下区Nestin阳性细胞的免疫组化观察

目的　探讨成人侧脑室下区 (SVZ)Nestin阳性细胞的分布及其化学特点。方法　采用 3 3 1B、10C2、Rat4 0 1、GFAP、NSE和viminten等神经细胞标志物对成人SVZ区进行免疫组织化学研究。结果　SVZ区存在较多Nestin反应阳性细胞 ,GFAP免疫阳性细胞及较少的NSE免疫阳性细胞。Nestin免疫反应阳性细胞可分为两类 ,一类为卵圆形 ,胞体较大 ,少有纤维突起 ;一类为星形 ,胞体较小 ,发出多支放射状的纤维突起。Nestin免疫阳性细胞均不与GFAP及NSE发生交叉反应。成人SVZ区细胞未见有viminten的表达。结论　成人SVZ区可能存在神经前体细胞和星形胶质样Nestin免疫阳性细胞。     

Alcian blue and epithelial membrane antigen are useful markers in differentiating benign from malignant papillae in thyroid lesions

Summary Immunohistochemistry for epithelial membrane antigen (EMA) and histochemistry for alcianophilic substances were performed in 17 cases of papillary thyroid carcinoma (PTC) and 11 cases of benign thyroid lesions showing papillary changes (7 diffuse hyperplastic goitres-Graves'disease; 4 colloid cystic goitres). In all PTCs the glycocalix of the cells lining the papillary structures was stronly positive with anti-EMA antiserum. Alcian blue pH 2.5 stain (AB 2.5) was also positive in 15 of these cases. In contrast, no cases of benign thyroid lesions showed AB 2.5 positivity in the cells lining the papillary structures and the positivity with anti-EMA antiserum, present in only 5 out the 11 cases, was focal and very weak. These results indicate that the presence and distribution of EMA and alcianophilic substances may be useful in distinguishing benign from malignant thyroid lesions containing papillae.     

Immunohistochemical observations of keratins,involucrin, and epithelial membrane antigen in urinary bladder carcinomas from patients infected withSchistosoma haematobium

Summary Squamous cell carcinomas of the urinary bladder and the epithelial lesions associated with infection bySchistosoma haematobium were histopathologically and immunohistochemically described for keratin proteins (TK, 41–65 kDa; KL1, 55–57 kDa; PKK1, 40, 45 and 52.5 kDa), involucrin, and epithelial membrane antigen (EMA). Normal urothelial epithelium was positive for all keratins, and showed absent or slight reactions for involucrin and EMA in superficial umbrella cells. The intestinal type of epithelium was composed of columnar cells and small basal cells; TK was positive in the basal cells, KL1 staining was positive in the columnar cells, whereas PKK1 was negative or slight in the columnar cells. Involucrin was confined to columnar cells. Squamous metaplastic epithelium showed a rather regional keratin distribution: TK was distributed in all layers, KL1 decorated upper spinous and granular layers, but PKK1 did not bind, and involucrin staining existed only in upper spinous and granular cells. Keratin expression in squamous cell carcinomas indicated heterogeneity and its stainability was dependent on the degree of keratinization: The G 1 type revealed strong reaction, the G 2 type showed a similar distribution pattern, but the staining intensity was less, and the G3 type showed irregular staining with decreased intensity. Involucrin staining was limited to keratinized cells of carcinoma as was that for EMA.     

微管相关蛋白2和巢蛋白在人胚胎脊髓的表达

目的 探讨微管相关蛋白2(MAP-2)和巢蛋白在人胚胎脊髓发育阶段的分布规律及其表达意义.方法 应用免疫组织化学法,检测第2、3、4月龄段共16例人胚胎脊髓前角、中央管及后角中MAP-2和巢蛋白的表达、分布状况.结果 第2～4个月龄段,人胚胎脊髓内均可见巢蛋白表达阳性的神经纤维分布,随着胎龄的增大,脊髓前角处巢蛋白阳性...     

The presence and location of epithelial implants and implants with epithelial proliferation may predict a higher risk of recurrence in serous borderline ovarian tumors: a clinicopathologic study of 188 cases

Serous borderline ovarian tumors have a favorable prognosis, and recurrences are uncommon. The factors influencing recurrence are not fully understood. Epithelial inclusions are identified in serous borderline ovarian tumors and are traditionally referred to as epithelial implants, which often show epithelial proliferation. We investigated whether the presence of epithelial implant and epithelial proliferation portends a higher risk for recurrence of serous borderline ovarian tumors in patients who underwent surgical removal of these tumors. Also examined was whether the anatomical site of epithelial implant and epithelial proliferation was associated with a higher risk of recurrence. One hundred eighty-eight cases of pure serous or predominantly serous borderline ovarian tumors were studied for the presence of epithelial implant and epithelial proliferation, and subsequent recurrences were recorded. The anatomical sites of epithelial implant and epithelial proliferation were compared between serous borderline ovarian tumors with or without recurrence. Statistical analysis was performed using the χ(2) test. Epithelial implant was noted in 106 cases (56%), and epithelial proliferation, in 26 cases (14%). Recurrence was identified in 10.4% cases with epithelial implant and 23% cases with epithelial proliferation. Statistical analyses of patients with recurrence showed significant differences in the following groups: epithelial implant versus no epithelial implant (P < .025) and epithelial proliferation versus no epithelial implant (P < .001). Recurrence rates were higher in the epithelial implant and epithelial proliferation groups as compared with no epithelial implant or epithelial proliferation groups. Epithelial implant and epithelial proliferation appear to pose a statistically significantly higher risk of recurrence in serous borderline ovarian tumors as compared with the absence of epithelial implant. Although the anatomical location of such implants was not significantly associated with a higher risk, the presence of epithelial proliferation at multiple sites was more frequently seen in recurrent serous borderline ovarian tumors.     

An immunohistochemical comparison of cytokeratin 7, cytokeratin 15, cytokeratin 19, CAM 5.2, carcinoembryonic antigen, and nestin in differentiating porocarcinoma from squamous cell carcinoma

The distinction of porocarcinoma from squamous cell carcinoma is clinically relevant but can often be a diagnostic dilemma. Current markers reported to be helpful in diagnosing porocarcinoma include carcinoembryonic antigen and cytokeratin 7; however, their expression has been demonstrated in 30% to 80% and 13% to 22% of squamous cell carcinoma cases, respectively. In this study, we assessed immunohistochemical expression of cytokeratin 7, cytokeratin 15, cytokeratin 19, CAM 5.2, carcinoembryonic antigen, and nestin in 67 cases (39 porocarcinomas and 28 moderately differentiated squamous cell carcinomas) to determine their use as histologic adjuncts. Expression of carcinoembryonic antigen, cytokeratin 19, cytokeratin 7, CAM 5.2, cytokeratin 15, and nestin was seen in 77%, 67%, 64%, 51%, 49%, and 13% of porocarcinomas, respectively; and in 57%, 18%, 26%, 32%, 30%, and 37% of squamous cell carcinomas, respectively. Of these, cytokeratin 19 was the most specific (specificity, 82%) in detecting porocarcinomas, and carcinoembryonic antigen was the most sensitive (sensitivity, 77%). By χ(2) test, statistically significant P values (<.05) were observed for cytokeratin 7, cytokeratin 19, and nestin in the distinction of porocarcinoma from squamous cell carcinoma. However, in a logistic regression and stepwise selection for predicting a porocarcinoma, statistical significance was observed only for cytokeratin 19 (P = .0003). In conclusion, we found cytokeratin 19 to be a helpful marker in the distinction of porocarcinoma from squamous cell carcinoma, although a focal staining pattern can be seen in a third of cases. The diagnostic sensitivity and specificity appear to be significantly improved using a selected panel of immunohistochemical stains that include cytokeratin 7, cytokeratin 19, and nestin.     

Detailed investigation of the diagnostic value in tumour histopathology of ICR.2, a new monoclonal antibody to epithelial membrane antigen

The production and detailed immunostaining properties of a new rat monoclonal antibody (ICR.2) to epithelial membrane antigen are reported. The antibody was selected for its ability to compete with the polyclonal antiserum (M7), used in the original immunohistological studies, in order that it might serve as a direct replacement in diagnosing epithelial tumours. Most of the staining reactions on normal tissues were identical to those previously reported with M7 but there were some important differences. They included: positivity of renal and adrenal capsular fibroblasts, perineurium, some myoepithelial and smooth muscle cells, occasional osteoblasts and squamous and thyroid follicular epithelium in the normal state. The intercellular canaliculi of sweat glands and secretory canaliculi of gastric oxyntic cells were clearly demonstrated. These staining reactions could be obtained with M7 when a sensitive detection system was used although the results were usually weak and inconsistent. Nearly all adenosquamous and transitional carcinomas were positive. The remaining tumours fell into three major groups: (1) those which were consistently or nearly consistently negative--melanoma, seminoma, rhabdomyosarcoma, alveolar soft part sarcoma, adrenal cortical carcinoma, granulocytic sarcoma, paraganglioma, non-Hodgkin's lymphoma. Hodgkin's disease and embryonal carcinoma: (2) those which were either negative or positive with distinctive patterns of staining--basal cell carcinoma, embryonal tumours: and (3) non-epithelial tumours that were consistently positive--epithelioid sarcoma, synovial sarcoma, osteosarcoma, chordoma and myeloma--or positive in a significant minority of cases--leiomyosarcoma, malignant fibrous histiocytoma, clear cell sarcoma of tendon sheath, various neuroectodermal tumours.(ABSTRACT TRUNCATED AT 250 WORDS)     

Usefulness of epithelial membrane antigen (EMA) to discriminate between perineural invasion and perineural indentation in prostatic carcinoma

AIMS: Perineural invasion (PNI) is one of the few unequivocal criteria to diagnose adenocarcinoma of the prostate. Distinguishing PNI from perineural indentation (PNIn), however, is sometimes difficult. The aim of this study was to discriminate between PNI and PNIn using EMA immunohistochemistry. METHODS AND RESULTS: We selected representative sections from 87 prostatectomies with prostatic adenocarcinoma. Normal peripheral nerves were continuously encircled with perineurium, which was immunoreactive for EMA. We identified 1319 PNI by carcinomas, 368 PNIn by carcinomas, and 303 PNIn by benign glands. We categorized the EMA immunoreactivity patterns into three classes: samples that displayed discontinuity or complete loss of the perineurium (Type A), samples where there were carcinomas or benign glands in the perineural space or peripheral nerves (Type B) and samples that showed no changes in the perineurium (Type C). For PNI we observed Type A, Type B, and Type C patterns in 55.3%, 24.8% and 19.9% of carcinomas, respectively. The incidence of each of those patterns in PNIn by carcinomas was 32.1%, 14.9% and 53.0%, respectively. Cases of PNIn by benign glands showed Type A or Type C patterns. They did not, however, exhibit Type B patterns. CONCLUSION: EMA immunostaining will aid the diagnosis of prostatic adenocarcinoma.     

Immunohistochemical detection of cytokeratin and epithelial membrane antigen in leiomyosarcoma: a systematic study of 100 cases

Although 'aberrant' expression of the epithelial markers, cytokeratin (CK) and epithelial membrane antigen (EMA), in leiomyosarcoma has been described previously, there has not been a study of this phenomenon with clinicopathological correlation in a large series of lesions at different anatomical sites. We investigated systematically the immunohistochemical reactivity for CK and EMA in 100 cases of leiomyosarcoma. CK and EMA were positive in 38% and 44% of the cases, respectively. Although staining was usually focal, extensive immunoreactivity was observed in 11% with CK and 6% with EMA. There was no correlation between immunoreactivity for CK and EMA in leiomyosarcomas and non-neoplastic smooth muscle at the same location. Immunoreactivity for CK and EMA was not correlated with the location, age, sex, histological grade, or histological features, except for more frequent EMA positivity in vascular and uterine tumors than in soft tissue cases. These results indicate that CK and/or EMA-positive leiomyosarcomas do not have distinctive clinicopathological features differing from those of negative cases. However, the considerable frequency of immunoreactivity for these epithelial markers in leiomyosarcoma, occasionally with diffuse and strong immunopositivity, should be recognized as a potentially serious diagnostic pitfall in the differential diagnosis of other malignant spindle cell neoplasms.     

Practical utility of insulin‐like growth factor II mRNA‐binding protein 3, glucose transporter 1, and epithelial membrane antigen for distinguishing malignant mesotheliomas from benign mesothelial proliferations

The differentiation of malignant mesotheliomas and benign mesothelial proliferations is crucial in determining patient care and prognosis. But, this distinction can be extremely difficult, particularly in small biopsies. Recently, insulin‐like growth factor II mRNA‐binding protein 3 (IMP3) and glucose transporter 1 (GLUT‐1) have been reported as specific and sensitive markers in the distinction of mesotheliomas from benign mesothelial proliferations. The purpose of this study is to evaluate the utility of IMP3, GLUT‐1, and epithelial membrane antigen (EMA) immunohistochemistry for distinguishing mesotheliomas from benign mesothelial proliferations. Immunoexpression of IMP3, GLUT‐1, and EMA was evaluated in 88 malignant mesotheliomas, 35 adenomatoid tumors, and 20 benign lung tissues with reactive mesothelial cells. The sensitivity for IMP3, GLUT‐1, and EMA was 37%, 21%, and 41%, respectively. The specificity for IMP3, GLUT‐1, and EMA was 100%. When IMP3, GLUT1, and EMA combined, the sensitivity was 66% for IMP3/EMA staining, 53% for GLUT‐1/EMA staining, and 45% for IMP3/GLUT‐1. Use of IMP3 and EMA together is more helpful to distinguish malignant mesotheliomas from benign mesothelial proliferations than the use of IMP3 or EMA alone.     

Epithelial membrane antigen in the cytodiagnosis of effusions and aspirates: immunocytochemical and ultrastructural localization in benign and malignant cells

Immunoreactivity for epithelial membrane antigen (EMA) was evaluated in exfoliated benign and malignant cells using immunoperoxidase and immunogold techniques. In addition, protein A-colloidal gold was used for ultrastructural localization of EMA. Our results suggest that EMA is useful in distinguishing adenocarcinoma cells (strongly positive) from reactive mesothelial cells (negative or weakly positive), lymphoid cells (negative), and a variety of nonepithelial neoplasms (negative) with which they may be confused. Exfoliated cells from two mesotheliomas were also strongly positive for EMA. Ultrastructurally, EMA was distributed in a dense, even, linear pattern along the cell membrane and microvillous surface processes of adenocarcinoma cells. A similar but sparse distribution pattern was observed in reactive mesothelial cells. These observations reflect the increased sensitivity and higher resolution of the immunogold technique.     

Immunohistochemical differences between intracranial germinomas and their gonadal equivalents. An immunoperoxidase study of germ cell tumors with epithelial membrane antigen, cytokeratin, and vimentin

Twenty-six intracranial germ cell tumours (11 germinomas, 10 teratomas, 2 endodermal sinus tumours, 1 teratocarcinoma, and 2 undifferentiated embryonal carcinomas) and 26 gonadal germ cell tumours (13 testicular seminomas, 2 ovarian dysgerminomas, 9 ovarian teratomas, and 2 myometrial choriocarcinomas) were studied by immunoperoxidase with monoclonal antibodies (MAbs) against epithelial membrane antigen (EMA), cytokeratin, and vimentin. Typical tumour cells in three of the 11 germinomas (two of the latter being situated in the posterior fossa) expressed both EMA and cytokeratin, whereas those in the seminomas and dysgerminomas did not. In one seminoma, a few multinucleated giant cells expressed cytokeratin. In three of seven germinomas, vimentin-positive tumour cells were found, but all seminomas and dysgerminomas were negative. In the other forms of intracranial and gonadal germ cell tumours, epithelial and mesenchymal elements displayed the expected patterns of immunoreactivity to the respective determinants. The immunoperoxidase differences between the intracranial germinomas and their gonadal equivalents indicate that, in the former, early epithelial or mesenchymal differentiation of the primordial germ cells may be present. The findings draw attention to the heterogeneous cellular composition of these otherwise morphologically homogeneous-appearing tumours and, especially in the posterior fossa, to their transitional links to the immature teratomas.     

Enrichment and partial enzyme characterization of ATPase activity associated with the outward-facing membrane complex and inward-facing membrane of the surface epithelial syncytium of Schistosoma mansoni

The outward-facing (OFM) and inward-facing (IFM) membranes of the surface epithelial syncytium of Schistosoma mansoni were separated by sequential exposure to saponin solutions. The OFM, containing both inner and outer bilayers, contained ATPase activity that was stimulated by Mg²⁺ and Na⁺, but not K⁺ or HCO₃^?, and was inhibited by Ca²⁺ and ethacrynic acid. The OFM enzyme was unaffected by ouabain, oligomycin, SCN^? and azide and had a pH optimum of 7.5. The OFM ATPase therefore has properties similar to ATPases characterized from the apical membrane of a variety of epithelial cells where it is thought to augment the regulatory cell volume decreasing function of (Na⁺+K⁺)Mg²⁺?ATPase. The IFM contained ATPase activity that was stimulated by Mg²⁺, Na⁺ and K⁺, and was inhibited by ouabain indicating that the IFM enzyme was the Na⁺-pump ATPase. The results are discussed in terms of the transepithelial transport function of the surface epithelial syncytium and a Ca²⁺-ATPase reported previously from the OFM of S. mansoni.     

Ki-1 lymphomas in childhood: Immunohistochemical analysis and the significance of epithelial membrane antigen (EMA) as a new marker

Summary Two cases of Ki-1 lymphomas in childhood were analyzed immunohistochemically and immunoelectron microscopically. They expressed Hodgkin's disease associated antigen, Ki-1, interleukin-2 receptor (IL2R), OKT9, and HLA-DR. Histologically, the tumour cells were large in size with abundant cytoplasm and atypical nuclei. Lymph node involvement was characterized by parafollicular and marginal sinus infiltration. These features were identical to those reported in Ki-1 lymphomas. Electron microscopically tumour cells had abundant cytoplasmic organelles with pleomorphic nuclei but had no specific granules. Some tumour cells had marked interdigitation of cell membrane. Immunoelectron microscopically Ki-1 was positive on cell membrane. Tumour cells had no T-cell or B-cell antigens except for Leu-3 (T4). Unexpectedly they expressed epithelial membrane antigen (EMA) strongly. EMA was positive on cell membrane and in the cytoplasm. EMA was detected effectively in paraffin-embedded sections. Among the malignant lymphomas in childhood tested, two cases were EMA-positive. The pattern of EMA-reactivity and the histology were very similar to Ki-1 lymphomas. These results strongly suggest that Ki-1 lymphomas in childhood may arise from non-lymphoid haematopoietic cells and that EMA can be used as a new marker to distingish certain type of Ki-1 lymphomas in childhood.     

Epithelial membrane antigen expression by the perineurium of peripheral nerve and in peripheral nerve tumours

Specimens of normal peripheral nerve and a series of peripheral nerve lesions have been immunostained with three different anti-epithelial membrane antigen (EMA) monoclonal antibodies. Sites of EMA immunoreactivity have been confirmed within perineurial cells of peripheral nerve, noted within the capsule of Schwannomas and palisaded encapsulated neuromas, and also detected with traumatic neuromas and plexiform neurofibromas. No expression was detected within simple neurofibromas, diffuse neurofibromas or within malignant Schwannomas. These sites of EMA expression concur with the suggested involvement of perineurial cells in the formation of the particular lesions. The relationship between EMA expression by the perineurium and the piaarachnoid membrane is discussed.