Staining For Keratin Research Articles

Epithelioid Hemangioendothelioma of the Anterior Mediastinum Clinicopathologic, Immunohistochemical, and Ultrastructural Analysis of 12 Cases

Twelve cases are reported of primary epithelioid hemangioendothelioma of the anterior mediastinum. Patient ages ranged from 19 to 62 years (mean, 49.4); three were women and nine were men. Seven patients presented with symptoms due to compression of surrounding structures; the remainder were asymptomatic and the lesions were discovered on routine chest x-ray films. The tumors measured from 4.5 to 13.5 cm in greatest diameter; they were encapsulated and well-circumscribed in seven cases and locally infiltrative in five. Histologically, a spectrum of features was observed ranging from those classically described for low-grade epithelioid hemangioendothelioma at other locations--including cells with abundant eosinophilic cytoplasm showing prominent vacuolization and intracellular lumen formation, few mitotic figures, and myxoid changes in the stroma--to more pronounced cytologic atypia, increased mitotic activity, and areas of necrosis. Metaplastic bone formation and osteoclast-type giant cells were observed in five cases, and four tumors displayed focally a prominent intravascular papillary endothelial component. Immunohistochemical studies showed positive staining of the neoplastic cells with factor VIII-related antigen and vimentin and focal staining in most cases with Ulex europaeus lectin. Stains for broad-spectrum keratin, CAM-5.2, S-100 protein, CD34, actin, and desmin were negative. Electron microscopic examination in three cases showed features distinctive for epithelioid vascular endothelial cells, including abundant cytoplasmic intermediate filaments, basal lamina material, marked pinocytotic activity, and primitive intracytoplasmic lumen formation. All cases were treated by surgical excision. Follow-up information was available in nine patients; seven patients were alive and well without evidence of disease 2-21 years after diagnosis (mean follow-up, 8 years); one patient had a recurrence after 1 year and died due to complications of surgery, and another patient died after 1 year of undetermined causes. Despite their often ominous clinical, radiological, and pathological features, epithelioid hemangioendotheliomas arising in the anterior mediastinum appear to behave as low-grade malignant neoplasms that may be adequately controlled in most instances by surgery alone.

Keratin staining pattern in clinically normal and diseased oral mucosa of lichen planus patients

The keratin pattern in oral epithelia is related to the type of terminal differentiation observed morphologically (keratinization/nonkeratinization) and to the presence or absence of epithelial dysplasia. Furthermore, it has been suggested recently that inflammatory phenomena influence the keratin expression in human gingiva. The aim of the present study was to describe the keratin pattern in oral lichen planus (OLP) lesions, which are well known to be characterized by hyperkeratinization and severe inflammatory changes, in order to elucidate the role of inflammation in keratin expression of oral epithelia. Tissue sections were stained with antikeratin antibodies directed to groups of keratins (AE1 and AE2) and to single keratin proteins (Nos. 5, 8, 13, and 19). The keratin pattern in OLP lesions differed in some respects from that of leukoplakias and frictional keratoses as characterized in previous studies. No consistent patterns for use in a diagnostic context were found. However, the changes in OLP lesions did not mimic those previously described in inflamed gingival specimens and in oral epithelial dysplasias. Thus, the results encourage further studies on the potential diagnostic use of keratin expression in premalignant oral lesions. Furthermore, the study suggests that the inflammatory reaction seen in OLP lesions does not influence keratin expression in a way comparable with the suggested influence of inflammation in gingival specimens.

Cytochemical identification of programmed cell death in the fusing fetal mouse palate by specific labelling of DNA fragmentation.

The process of palate fusion was examined in 13- and 14-day-old mouse fetuses by using in situ staining for nuclear DNA fragmentation (TUNEL method) and immunofluorescent staining for keratin, with special reference to the disruption of the midline epithelial seam. TUNEL-positive cells were found in the disappearing midline seam and the oral and nasal epithelial triangles at some late stages of palate fusion, but not in the palatal shelves prior to contact or in the intact midline epithelial seam. It seems that DNA fragmentation or apoptosis is required for the midline epithelial seam to disrupt, but may not be necessary for initial contact of palatal shelves or for the epithelial fusion of opposing palatal shelves. A similar sign of apoptotic cell death was observed in the disappearing epithelial seam between the fusing nasal septum and dorsal palate. We have demonstrated that apoptotic programmed cell death does occur at some stages of palate fusion, although the present results do not exclude the possibility of epithelial-mesenchymal transformation and the oral and nasal migration of midline epithelial cells.

Malignant Peritoneal Mesothelioma Mimicking Mesenteric Inflammatory Disease

A case of malignant peritoneal mesothelioma mimicking mesenteric inflammatory disease (MID) is presented. The patient had mesenteric and omental lesions characterized at biopsy by extensive fibrosis of fat tissue with mild to moderate inflammation. One year later, post-mortem examination revealed a well-differentiated epithelial mesothelioma. Immunohistochemical stains for keratin and vimentin were diffusely positive, whereas EMA showed a membranous staining of scattered cells. CEA, Ber-EP4, B72.3 and Leu-M1 were negative. In addition, actin monoclonals decorated groups of cells pertaining to the tumoural component. Immunostains of sections from retrieved paraffin blocks of the previous biopsy showed that the bulk of the spindle-shaped and histiocytic-like cells present in the fibrous streams was strongly labeled by low-molecular-weight keratin, and coexpressed vimentin and actin. EMA showed a membranous staining of sporadic spindle and round cells. The other immunostains were invariably negative. This immunohistochemical pattern closely corresponded to the immunophenotype of the mesothelial tumour detected at autopsy and was very suggestive of myofibroblastic/submesothelial cell origin. The quantitative evaluation of silver nucleolar organizer regions (Ag-NORs) demonstrated high levels of cell proliferation in both surgical and autopsy tissue samples.

Rhabdomyosarcomas of the anterior mediastinum: Report of four cases unassociated with germ cell, teratomatous, or thymic carcinomatous components

Four cases are presented of primary anterior mediastinal tumors in young adults that were characterized by solid, infiltrative lesions showing histologic and immunohistochemical features of rhabdomyoblastic differentiation. The patients were three men and one woman between 19 and 27 years of age (mean age, 23 years). All patients presented with symptoms referable to their tumors, including cough, chest pain, dyspnea, and left-sided pleural effusion. Grossly and radiographically, the lesions were characterized by their solid, infiltrative appearance. Histologically, two cases corresponded to the solid variant of alveolar rhabdomyosarcoma, one case was an embryonal rhabdomyosarcoma with a predominant spindle cell component, and the remaining case showed the features of a pleomorphic rhabdomyosarcoma. No glandular, epithelial, or other component could be identified in any of the tumors on extensive sampling. Immunohistochemical studies showed positive staining of the tumor cells with actin, desmin, and vimentin antibodies, with focal positivity for myoglobin in three cases and focal positive staining with S-100 protein in one case. Stains for low and high molecular weight keratin, carcinoembryonic antigen, α-fetoprotein, human chorionic gonadotropin, placental alkaline phosphatase, leukocyte-common antigen, and neuronspecific enolase were negative. All patients experienced rapid recurrence and metastases within the first 6 months after diagnosis. Three patients died within this period due to their tumors; the fourth patient has been lost to follow-up. Pure primary rhabdomyosarcomas of the anterior mediastinum are highly aggressive neoplasms that should be distinguished from germ cell, teratomatous, or carcinosarcomatous tumors with a focal rhabdomyoblastic component.

Growth and differentiation of tracheal epithelial progenitor cells.

The purpose of these studies was to determine whether both basal and secretory rat tracheal epithelial (RTE) cells served as multipotent epithelial progenitors and whether both cell types gave rise to a similar "poorly differentiated" cell during the early phase of epithelial regeneration in denuded tracheal grafts. Griffonia simplicifolia I (GSI) lectin and flow cytometry were used for cell sorting. More than 98% of GSI-positive cells expressed plasma membrane alpha 1-3 terminal galactose (Gal), and 95% contained keratin 14 (K14), phenotypic markers for basal cells; < 1% were secretory or ciliated cells. Less than 2% of the GSI-negative cells expressed Gal or K14, but this fraction contained 16% ciliated cells and 54-79% secretory cells, dependent on whether periodic acid-Schiff staining or binding of an anti-secretory cell monoclonal antibody (RTE 12) was used as the criterion. Equal numbers of viable cells from either fraction were inoculated into denuded tracheal grafts, which were studied on days 1-14. At 24 h, greater numbers of GSI-negative than -positive cells were found attached to the graft wall; the keratin staining pattern of the attached cells was similar to that of the parent cell populations, but monoclonal antibody-detectable secretory and ciliated cell epitopes, originally present in the GSI-negative fraction, were lost. 5-Bromo-2'-deoxyuridine uptake was not seen at 24 h, but by 48 h all epithelial cells from both fractions entered the cell cycle. From 48 to 96 h, cells derived from either fraction were ultrastructurally indistinguishable; they were poorly differentiated and highly proliferative, and all expressed Gal and K14. A mature epithelium evolved from the poorly differentiated cells in both sets of grafts, but secretory and ciliated cells appeared earlier in grafts inoculated with GSI-negative cells. The results strongly suggest that in this model of tracheal epithelial regeneration both basal and secretory cells "dedifferentiated" into a similar highly proliferative phenotype from which a mucociliary epithelium "redifferentiated."

Immunohistochemical Profile of Synovial Sarcoma with Emphasis on the Epithelial-type Differentiation: A study of 49 Primary Tumours, Recurrences and Metastases

The relationship between biphasic (BSS) and monophasic (MSS) subtypes of synovial sarcoma (SS) as well as the relationship between cells of solid/glandular areas and the spindle cells of BSS remain controversial. In order to further evaluate the immunohistochemical phenotype of SS we studied 34 primary tumours (15 BSS; 19 MSS), 7 recurrences (4 from primary BSS; 3 from primary MSS) and 8 metastases (7 BSS; one MSS), using several antibodies (EMA, CEA, keratins 1, 4, 5/6, 7, 8, 13, 18, 19, 20, vimentin, collagen IV and laminin) that work in paraffin-embedded material. Spindle cells outside solid/glandular areas of BSS and in MSS showed immunoreactivity for keratins 5/6, 7, 8, 18 and 19. The transition of solid/glandular areas to surrounding spindle cells also showed keratin staining and failed to show a distinct separation regarding the immunoreactivity for laminin and collagen IV. Peripheral cells of solid/glandular areas were immunoreactive for vimentin. No major differences were observed between immunophenotypical cell profiles of BSS and MSS, apart from the exclusive immunostaining of solid/glandular areas of BSS for keratin 13 and CEA. Downgrading of keratin and extracellular matrix antigens immunoreactivity was observed when primary tumours were compared to recurrent and/or metastatic tumours of both subtypes (MSS and BSS). We conclude that SS should be regarded as carcinomas of soft tissues with an immunohistochemical phenotype depending on the degree of epithelial differentiation: spindle cells (MSS and BSS) predominantly expressing simple keratins, and poorly differentiated (solid/glandular) as well as well-differentiated (glandular) areas (BSS) expressing, in addition, complex epithelial-type keratins.

Role of growth factors and estrogen as modulators of growth, differentiation, and expression of gonadotropin subunit genes in primary cultured sheep pituitary cells.

Although the pituitary is known to produce several growth factors, their effects on pituitary cell growth and differentiation are still unclear, particularly in normal tissue. Using primary cultures of aged ewe pituitaries cultured in serum-free conditions, we studied the effects of basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), transforming growth factor-beta (TGF beta 1), insulin, and 17 beta-estradiol (E2) on the growth, differentiation, and expression of gonadotropin subunit genes. After 72-h incubation of the monolayer (day 5) with optimal concentrations of each factor, [3H]thymidine incorporation was increased significantly (P < 0.01) over the control values by 33 +/- 8% (mean +/- SEM; n = 3; 10 nM E2), 36 +/- 10% (1 ng/ml TGF beta 1), 83 +/- 12% (10 ng/ml bFGF), and 118 +/- 12% (1 nM EGF). Insulin showed a two-phase dose-response curve, increasing [3H]thymidine uptake by 34 +/- 9% at 10 ng/ml and by 63 +/- 13% at 10 micrograms/ml. Cell counting using a Coulter counter confirmed these results. Characterization of cell types by immunocytochemistry (avidin-biotin-peroxidase complex technique) revealed that the cell cultures were predominantly gonadotrophs. However, the cultures contained cells that did not stain with any specific ovine or human antiserum against LH beta, FSH, TSH beta, PRL, GH, ACTH, or glial fibrillary acidic protein, but were of epithelial cell lineage, as shown by positive keratin staining. Treatment with EGF and bFGF increased the proportion of these undifferentiated pituitary cells and induced changes in their morphology to large cuboidal cells containing large nuclei. After treatment with E2, insulin, and TGF beta 1, pituitary cells remained differentiated, although with E2, staining for gonadotrophs was much reduced. Northern blot analysis revealed that E2 treatment for 0-48 h progressively reduced the mRNA for FSH beta (16 +/- 4.5% of control values) and LH beta (12.4 +/- 2.5%), but had little effect on the common alpha-subunit (88.4 +/- 4.6%). TGF beta 1, however, stimulated the expression of FSH beta subunit gene by 142 +/- 4.6% (P < 0.01) of the control value, but had no significant effect on LH beta and common alpha-subunit genes. Insulin, EGF, and bFGF showed no significant effect on the expression of these three subunit genes. The data define the direct effects of growth factors and E2 on the growth and differentiation of normal sheep pituitary cells and gonadotrophs in particular, which may be of relevance to the pathophysiology of the pituitary and in the multistage process of pituitary tumorigenesis.

Malignant transformation of human bronchial epithelial cells by radon-simulated alpha-particles.

Epidemiological studies have shown that inhalation of radon is associated with an increased risk for bronchogenic carcinoma in uranium miners. These alpha-emitting radon daughters also represent the largest component of background radiation to the general public. In the present study, the oncogenic transforming effects of single versus multiple doses of radon-simulated alpha-particles were examined using human papillomavirus-immortalized human bronchial epithelial cells. Endpoints such as growth kinetics, resistance to serum and 12-O-tetradecanoylphorbol-13-acetate-induced terminal differentiation, anchorage-independent growth and tumorigenicity in nude mice were used to assess the various stages of transformation in the bronchial epithelial cells. We show here, for the first time, that immortalized human cells in culture can be malignantly transformed by a single 30 cGy dose of alpha-particles. Transformed cells produced progressively growing subcutaneous tumors upon inoculation into athymic nude mice. Immunofluorescent staining of keratin and isozyme analysis of the cell lines subsequently generated from these tumors indicated that the cells were of human epithelial origin. Analysis of genomic DNA from the tumorigenic cell lines using PCR amplification and restriction enzyme analysis demonstrated no point mutation at either codon 12/13 or 61 in any of the ras oncogenes examined (K-, N- and H-ras). This system provides an opportunity to study the cellular and molecular changes at the various stages in radiation carcinogenesis involving human cells.

Adamantinoma of the long bones: keratin subclass immunoreactivity pattern with reference to its histogenesis.

To gain more insight into the differentiation characteristics of the epithelial cells of the adamantinoma of the long bones, we studied the specific keratin immunoreactivity pattern using monoclonal antibodies on 34 primary, recurrent, or metastatic specimens of 22 patients. The results revealed the widespread presence of keratins 14 and 19 in all specimens studied; 74% showed immunoreactivity of keratin 5, and focal staining of keratin 17 was detected in 50%. Keratins 7 and 13 were found in three adamantinoma specimens. This keratin immunoreactivity pattern was independent of histologic subtype, despite marked variety in differentiation pattern, suggesting a common histogenesis for all subtypes of adamantinoma. Furthermore, the pattern was conserved both in local recurrences and in metastasis. The major pattern found in our study differs significantly from other bone and soft tissue tumors with known epithelial characteristics, e.g., synovial sarcomas, chordomas, and epithelioid sarcomas, in that it lacks immunoreactivity of keratins 8 and 18. Our results suggest a basal epithelial cell-like differentiation of adamantinomas.

Chondroid Lipoma

We report 20 cases of a peculiar fatty tumor that occurred in 16 female and four male patients who were 14-70 years old (median, 36 years). Most lesions were situated in the subcutis, superficial muscular fascia, or skeletal muscle of the limbs and limb girdles (15), trunk (3), and the head and neck (2). They were 1.5-11 cm in size (median, 4 cm) and usually described as yellow (13 of 15) and encapsulated (13 of 15). Microscopically they were well circumscribed and consisted of nests, strands, and sheets of eosinophilic and vacuolated cells, which contained glycogen and fat droplets, resembling brown fat cells, lipoblasts and chondroblasts. In all cases there was a variable background of mature adipose tissue associated with a prominent, partially fibrinous to hyalinized myxoid matrix that contained acid mucopolysaccharides usually resistant to hyaluronidase digestion. Several cases had foci of serous atrophy, perivascular fibrosis, and small thrombi; two were focally calcified. The lesions stained for S100 protein (11 of 12), vimentin (10 of 11), and CD68 antigen with KP1 (9 of 11); focal staining for keratin was also seen (4 of 11), but none stained for epithelial membrane antigen or actin or with HMB45. Follow-up in 12 cases (median, 9.5 years) revealed no local recurrences or metastases. Despite its deep location and atypical cellular features, the lesion's nonaggressive behavior suggests it is benign and neither a myxoid liposarcoma nor a myxoid chondrosarcoma, with which it is most frequently confused. The presence of glycogen in vacuolated fat cells is similar to brown fat, and the presence of sulfated stromal mucins supports focal chondroid differentiation. Although the pathogenesis remains uncertain, a lipoma with hibernomatous features, myxoid change, chondroid metaplasia, and secondary degenerative features is favored over a lipogranulomatous process.

Intrahepatic cholangiocarcinoma with sarcomatous change. Clinicopathologic and immunohistochemical evaluation of seven cases

Although there have been a few reports dealing with the sarcomatous changes of intrahepatic cholangiocarcinoma, its clinicopathologic features as well as immunohistochemical nature remain obscure. Among 155 cases of intrahepatic cholangiocarcinoma, 7 cases of sarcomatous cholangiocarcinoma were chosen. Immunohistochemical studies using the avidin-biotin-peroxidase complex method were performed on these cases. The tumor showed both mucin-producing adenocarcinoma areas and sarcomatous areas, the latter being predominant in three cases and focal in the other four. All the sarcomatous areas consisted of atypical spindle cells arranged in sheets or bundles. Pleomorphic giant cells were observed in some sarcomatous components in five cases. Immunohistochemical staining for keratin and epithelial membrane antigen revealed apparent positivity in the sarcomatous components of five cases. The patients with these tumors showed aggressive intrahepatic spreading and widespread metastasis of the sarcomatous cells, and demonstrated poorer prognosis than those with ordinary cholangiocarcinoma, with one exception, a patient who remained disease-free for 3 years after surgery. These findings favor the possible epithelial origin of sarcomatous cells. Radical operation would be necessary for patients with this special type of cholangiocarcinoma.

Electron microscopic and immunohistochemical findings in a case of olfactory neuroblastoma.

A case of olfactory neuroblastoma is reported. Light microscopic examination showed various arrangements of poorly differentiated tumour cells forming either uniform sheets or convoluted cords of multiple cell layers orientated toward a richly vascular stroma. Electron microscopic examination showed the presence of abundant cytoplasmic filaments and processes, and dense core endocrine vesicles ranging from 100-160 nm in diameter in both the perinuclear region and tumour cell processes. Immunohistochemical staining was positive in most of the tumour cells for neuron specific enolase, and in a few cells for S-100 protein, vimentin, and serotonin, but staining for desmin and keratin produced no reaction.

Patterns of expression of intermediate filaments and S-100 protein in desmoplastic ameloblastoma.

Seventeen cases of desmoplastic ameloblastoma were examined immunohistochemically. Immunoperoxidase techniques were applied for detection of keratin, desmin, vimentin and S-100 protein expression in these tumors. The tumor epithelium of desmoplastic ameloblastoma exhibited weak, focal, inconstant keratin staining, weak, variable expression of S-100 protein, desmin immunoreactivity of mild to moderate intensity and vimentin non-reactivity. The pertinent literature on the immunohistochemistry of ameloblastomas is briefly reviewed.

Keratin and vimentin distribution patterns in the epithelial structures of the canine anal region.

The intermediate filament labeling pattern of the epithelial structures of the canine anal region was studied with different polypeptide specific keratin monoclonal antibodies (MoAbs) and with a monoclonal and polyclonal vimentin antibody. The epithelial structures in this region could be discriminated and characterized by differences in their keratin staining pattern. The basal cells in the different epithelial structures showed a similar staining pattern characterized by reactivity with MoAbs staining keratins 5, 8, 14, and 17. Columnar epithelial cells showed a completely different phenotype mostly characterized by reactivity with MoAbs staining keratins 7, 5, 8, 18, and 19. A restricted number of differentiated perianal gland cells showed perinuclear vimentin staining. Myoepithelial cells did not stain for vimentin, but, as other basal cells, were positive for MoAbs staining keratins 5, 8, 14, and 17.

Immunohistochemical stains in extramammary Paget's disease.

The histologic and immunohistochemical characteristics of 49 skin biopsy specimens from 49 patients with extramammary Paget's disease were studied. Patients with extramammary Paget's disease with and without underlying malignant disease were identified. Associated malignant lesions, present in 16 patients (33%), were transitional cell carcinoma of the bladder (n = 8), adenocarcinoma underlying the skin (n = 3), adenocarcinoma of the anus (n = 1), adenocarcinoma of the vulva (n = 1), apocrine carcinoma (n = 1), prostate carcinoma (n = 1), and carcinoma metastatic to the lung (n = 1). The main histologic feature was the presence of Paget's cells, predominantly at the base of the epidermis. In 6% of the cases, well-defined nests of large Paget's cells mimicked melanocytic nests. Carcinoembryonic antigen and Cam 5.2 (a monoclonal antibody that stains 40-kDa, 45-kDa, and 52.5-kDa low molecular weight keratins) were localized to the Paget's cells in 42 of 45 (93%) and 29 of 41 cases (71%), respectively. Forty-four of 46 lesions (96%) were mucin positive, as determined by Hale's colloidal iron stain. Absence of staining for colloidal iron and carcinoembryonic antigen occurred somewhat more frequently in patients with underlying malignant disease than in patients without tumors (13% vs. 0% mucin negative and 13% vs. 3% carcinoembryonic antigen negative, respectively). Although immunohistochemical staining for low molecular weight keratin may be used to confirm the diagnosis of extramammary Paget's disease, Cam 5.2 is not as sensitive as the colloidal iron or carcinoembryonic antigen stain.

Primary Malignant Ependymoma of the Lung

In a 64-year-old woman, a solitary pulmonary nodule developed 30 months after combination chemotherapy and thoracic irradiation had been administered for small-cell carcinoma of the ipsilateral lung. No evidence of extrapulmonary tumor was identified, and the nodule was excised. The well-circumscribed tumor had histologic features of a malignant ependymoma. Immunohistochemical staining showed strong reactivity for glial fibrillary acidic protein; staining for S-100 protein, Leu-7, and vimentin was less intense. Focal reactivity for epithelial membrane antigen was also present. Stains for keratin, synaptophysin, and chromogranin were negative. Electron microscopy showed cohesive cells, the cytoplasm of which contained intermediate filaments. Rare well-formed junctions were also noted. Flow cytometry of formalin-fixed paraffin-embedded tissue demonstrated DNA aneuploidy. Six months after the ependymoma was diagnosed, the patient, who had a history of hypertension, died of an intracerebral hemorrhage.

Immunohistochemistry with keratin monoclonal antibodies in canine tissues: urogenital tract, respiratory tract, (neuro-)endocrine tissues, choroid plexus and spinal cord.

Twelve oligo- or monospecific monoclonal antibodies (MoAbs) directed against human keratin types were used in an immunohistochemical study of the canine male and female urogenital tract, the respiratory tract, the adrenal gland, the (para-)thyroid gland, the choroid plexus and the spinal cord. The keratin MoAbs showed differences in staining patterns in the various epithelial tissues and the diverse epithelial cells. The kidney was characterized by a complex keratin staining pattern and the canine urothelium showed regional differences in keratin staining. Also in the female genital tract different keratin staining patterns were observed. Testicular and adrenal gland cells did not react with any of the keratin MoAbs. The keratin staining patterns in the various canine tissues showed, in addition to similarities, also distinct differences when compared to the staining patterns in corresponding tissues of other species, e.g. of man. These staining dissimilarities indicate that the reactivity patterns of the keratin MoAbs with restricted keratin immunoreactivity can not be always extrapolated from one species to another. Nevertheless, MoAbs directed against human keratin proteins can apparently be used to differentiate between various types of canine epithelia or epithelial compartments.

Immunohistochemistry with keratin and smooth muscle actin monoclonal antibodies in canine digestive tract and extramural glands.

The canine digestive system and its extramural glands (parotid gland, liver, pancreas) were immunohistochemically studied using a panel of twelve monoclonal antibodies (MoAbs) specific for human keratin proteins and for alpha-smooth muscle actin. Various epithelial tissues and cells were characterized by different keratin staining patterns. So, the epithelial lining of the upper alimentary tract was characterized by staining with the MoAb 6B10, specific for keratin-type (K) 4, and the absence of staining with the MoAbs directed against K 8 and 18 (CAM 5.2 and RGE 53, DE-K18 respectively), whereas the lower alimentary tract epithelium was not labeled by 6B10, but stained by the latter MoAbs. In the salivary glands the luminal and basal cells of the adenomeres as well as the different ductal structures could be immunohistochemically differentiated. The duct epithelium in liver and pancreas showed next to keratin staining characteristics in common with hepatocytes and exocrine pancreatic cells, additional staining by several keratin MoAbs. The keratin staining patterns in the canine tissues showed, in addition to similarities also distinct discrepancies when compared to the staining patterns in corresponding human tissues. Myoepithelial cells in salivary and oesophageal glands could be differentiated from other basally located epithelial cells by their exclusive immunoreactivity for alpha-smooth muscle actin. Canine pancreatic endocrine cells were not labeled by any of the keratin MoAbs. It is concluded that immunohistochemistry with polypeptide specific MoAbs specific for human keratin-types can be used to differentiate between different types of canine epithelial tissues and epithelial cells in the digestive tract. As a result such reagents may find their application in developmental biology and pathology of this species.

子宮内膜細胞診における腺細胞と間質細胞の鑑別 免疫染色を用いて

子宮内膜細胞診における腺細胞と間質細胞の鑑別 免疫染色を用いて