Immunohistochemical study during healing of free palatal mucosa grafts on plastic-embedded samples

This immunohistochemical study describes changes in the histology and in the distribution of the basement membrane components laminin and collagen IV as well as of the cytokeratins (CK)1/2/10/11, CK5/6, CK13, CK14, CK17, CK19 during the take of free split mucosa (epithelial and connective tissue) transplants in humans up to 36 months post-operative. Histology showed a flattening of the epithelial layer within the first 2 weeks after grafting, followed initially by an increase (25-30 layers, week 6) and later on by a decrease of cell layers in the epithelium (15-20 layers, week 20). From that time onwards, clear stratification and reteridges as signs of differentiation were present. Up to day 14 of graft take, the linear staining patterns for laminin and collagen IV were interrupted, which was not observed at any later stage. During this early interval CK5/6, CK1/2/10/11, CK14 and CK17 were expressed in all epithelial layers. The reactions for CK5/6 and CK1/2/10/11 were less intensive. At 6 weeks, CK1/2/10/11 stained the intermediate and superficial layers, being consistent with findings after longer graft take. CK5/6 reacted in the basal and intermediate cell layers, and CK13, CK14 and CK17 reacted in all layers. In the following period up to week 20, CK5/6 were found in the parabasal cells of the intermediate cell layers and the basal cells. CK14 staining was confined to these cell layers too, but also showed some reaction in the superficial layers. CK13 and CK17 were still bound to all layers. At 7 months post-operative, CK5/6 and CK14 were seen in their typical localisation in the basal cell layer and the parabasal cells of the intermediate layers, CK17 was seen mainly in the intermediate layer and CK13 was seen in focal areas of all layers. Anti-CK19 reacted only with single basal and parabasal cells up to week 20. These results suggest that during healing of mucosal autografts there is a sequence of changes in the expression of cell biological differentiation markers that may involve an epithelio-connective tissue interaction before the typical patterns for the donor side were observed again on the gingiva or mucosa of the hard palate.     

Clear cell variant of calcigying epithelia odontogenic tumor (CEOT) in the maxilla: report of a cse with immunohistochemical and ultrastructural investigations

A rare case of clear cell variant of calcifying epithelial odontogenic tumor is presented with immunohistochemical and ultrastructural investigations. A 14-year-old Japanese girl was admitted with a complaint of swelling in the right posterior maxilla. Radiological examination showed a well-circumscribed radiolucent lesion located close to the impacted third molar. After only a partial tumor excision, the tumor recurred 13 years later. It appeared radiologically as an irregular radiodensity, and a subtotal maxillectomy was performed. Histological examination showed sheets and/or strands composed almost entirely of clear vacuolated epithelial cells in a stroma containing intercellular amyloid-like material and calcification. Histochemical and ultrastructural analysis detected cytoplasmic glycogen granules in the clear cells, and positive immunoreactivities for cytokeratins 8, 13 and 19; filaggrin and anti-ameloblastoma antibodies suggested an odontogenic epithelial origin.     

Immunoprofile of a carcinosarcoma of the submandibular gland

Carcinosarcomas are a very rare group of true malignant tumors of the salivary gland. As the name indicates, the tumor is composed of an epithelial and a mesenchymal component, both malignant. We report a case of carcinosarcoma of the submandibular gland in an 86-year-old woman. The epithelial component showed a squamous carcinoma phenotype, whereas the mesenchymal component was morphologically similar to a fibrosarcoma. The epithelial component was strongly positive for CK13, CK14, and AE1/AE, and groups of positive cells were seen for CK19 and vimentin. The whole mesenchymal component was positive for vimentin, negative for cytokeratins, and focal cells were positive for smooth- muscle actin. Both components were strongly positive for P53 and Cyclin D1, and focally positive for MDM2. Rare multinucleated giant cells showed expression of CD68, and focal dendritical cells on carcinomatous nests were positive for S-100. The CK7, CK8, Factor XIIIa, c-erbB-2, P16, CDK-4, Rb1, and E2F-1 were not detected in these 2 groups of malignant cell populations.     

Canalicular adenoma arising in the upper lip: review of the pathological findings

This case report describes a rare case of canalicular adenoma arising in the upper lip of a 61-year-old male patient. Macroscopic examination of the tumor revealed a well-defined, smooth, firm, elastic hard, round nodule with a diameter of 1.0 cm. The cut surface was white. Histopathology showed that the tumor was an encapsulated mass with a complex cellular pattern of anastomosing duct-like or trabecular structures lined by a single layer of tall columnar epithelial cells, which were embedded in a loose, fibrous, and highly vascular connective tissue stroma. The tumor cells were immunoreactive to AE1/AE3, CK19 and S-100, were partially positive for CK7, CK8, GFAP and PCNA, but were negative for SMA, CK13, CK14 and vimentin.     

In situ hybridization study of cytokeratin 4, 13, 16 and 19 mRNAs in human developing junctional epithelium

Cytokeratins (CKs) are now considered to be reliable markers for following the development and differentiation of epithelial tissue. We have investigated the pathway of differentiation in human developing junctional epithelium using monoclonal antibodies and two-dimensional gel electrophoresis of mcrodissected tissue to identify CK 19. CK 16. CK 14. CK 13. CK 6. CK 5. CK 4 in the junctional epithelium (JE) over partially erupted human teeth. The CK profile was similar to that of developing oral epithelia. suggesting that the junctional epithelium in teeth during eruption is of odontogenic origin. The present study used in situ hybridization to determine the distribution of the mRNAs of CKs 19. 16. 13 and 4 in human developing junctional epithelium and to examine the correlation between mRNAs and their encoded proteins. CK 19 mRNA was abundant in the basal cell layers of the primary junctional epithelium (PJE) but less concentrated in the suprabasal layers. CK16. 13 and 4 mRNAs were abundant in the basal cell layers of the PJE. Tlie parabasal cell layers reacted intensely to the cRNA probe complementary to CK16 mRNA. as were the reactions in the suprabasal cell layers of the PJE for the CK 13 and 4 probes. Our results demonstrate that the PJE express the genes encoding for CKs 16 and 4 that have been revealed previously only by electrophoresis. They therefore confirm that the PJE is a well-differentiated stratified epithelium with a complex unique phenotype that produces CKs specific for basal cells (CK 19), CKs associated with hyperproliferation (CK 16). and finally those associated with stratification (CKs 4 and 13). Only synthesis of CK 19 protein and mRNA are strictly parallel. CKs 4 and 13 mRNAs are present in basal and suprasal cells, while their encoded proteins were not. except for CK 13 in suprabasal cell layers of PJE. where the amount of its mRNAs was coincident with the expression of the protein.     

Cytokeratins in epithelia of odontogenic neoplasms

Neoplasms and tumours related to the odontogenic apparatus may be composed only of epithelial tissue or epithelial tissue associated with odontogenic ectomesenchyme. The immunohistochemical detection of different cytokeratins (CKs) polypeptides and vimentin has made it easier to explain the histogenesis of many epithelial diseases. The present study aimed to describe the immunohistochemical expression of cytokeratins 7, 8, 10, 13, 14, 18, 19 and vimentin in the epithelial components of the dental germ and of five types of odontogenic tumours. The results were compared and histogenesis discussed. All cells of the dental germ were positive for CK14, except for the preameloblasts and secreting ameloblasts, in which CK14 was gradually replaced by CK19. CK7 was especially expressed in the cells of the Hertwig root sheath and the stellate reticulum. The dental lamina was the only structure to express CK13. The reduced epithelium of the enamel organ contained CK14 and occasionally CK13. Cells similar to the stellate reticulum, present in the ameloblastoma and in the ameloblastic fibroma, were positive for CK13, which indicates a nature other than that of the stellate reticulum of the normal dental germ. The expression of CK14 and the ultrastructural aspects of the adenomatoid odontogenic tumour probably indicated its origin in the reduced dental epithelium. Calcifying odontogenic epithelial tumour is thought to be composed of primordial cells due to the expression of vimentin. Odontomas exhibited an immunohistochemical profile similar to that of the dental germ. In conclusion, the typical IF of odontogenic epithelium was CK14, while CK8, 10 and 18 were absent. Cytokeratins 13 and 19 labelled squamous differentiation or epithelial cells near the surface epithelium, and CK7 had variable expression.     

A case of calcifying odontogenic cyst with numerous calcifications: immunohistochemical analysis

The purpose of this study was to investigate a case of calcifying odontogenic cyst (COC) in which numerous calcifications were observed not only in the lining epithelium, but also in the cyst wall, using cytokeratins 13 (CK13), 19 (CK19), and core binding factor a-1 (cbfa-1) as primary antibodies. Cells of Malassez's epithelial rest were stained as controls. Cells of the epithelial nests in the cyst wall were reactive for CK13, but their CK19 staining was similar to that observed in the lining epithelial cells. Calcifying nodules were reactive only for CK13. Cells of Malassez's epithelial rest were reactive for CK19 but not for CK13. Cbfa-1 positive reactivity was observed only in nuclei of spindle cells in the periodontal ligament. CK13 was positive superficial to the prickle cells. CK19 was positive in the basal cells of the oral mucosa. In the lining epithelium of the cyst, the expressions of CK13 and CK19 were similar to their immunoreactions in the oral mucosa. These results suggest that the odontogenic epithelium differentiated into squamous epithelial cells, which began as ghost cells in the COC, and that this process depended on the dystrophic calcification of differentiated odontogenic epithelial cells, not of osteogenic cells.     

Clear cell odontogenic carcinoma: case report with immunohistochemical findings adding support to the challenging diagnosis

Clear cell odontogenic carcinoma (CCOC) is a rare odontogenic tumor associated with aggressive clinical behavior, metastasis, and low survival. We report a case of CCOC affecting the mandible of a 39-year-old man. The tumor presented a biphasic pattern composed of clear cell nests intermingled with eosinophilic cells and separated by collagenous stroma. Immunoreactivity to cytokeratin (CK), specifically AE1/AE3 and CK 8, 14, 18, and 19 was found, as well as to epithelial membrane antigen (EMA). The tumor cells were negative for S100 protein, CK 13, vimentin, smooth muscle actin, laminin and type IV collagen. Low labeling indices for the proliferation markers Ki-67 and proliferating cell nuclear antigen and to p53 protein might predict a favorable prognosis for the lesion. A surgical resection was performed, followed by adjuvant radiotherapy. A 2-year follow-up has shown no signs of recurrence. The significance of histochemical and immunohistochemical resources in the correct diagnosis of CCOC is analyzed.     

Cytokeratin patterns of human oral mucosae in histiotypic culture.

In a three-dimensional culture model, oral epithelial differentiation was investigated ultrastructurally and biochemically for cytokeratin expression. Epithelia from the hard palate, gingiva and alveolar mucosa grown on freely floating collagen lattices populated with fibroblasts from homotypic origins, and fed with medium containing 10% delipidized fetal calf serum for 21 days before analysis, stratified and differentiated to basal cuboidal cells, polyhydral spinous cells and elongated superficial cells. The epithelium of palatal origin had non-nucleated superficial cells resembling orthokeratinized cells. The upper spinous cells had keratohyalin-like granules. The corresponding cells of gingival and alveolar mucosal origins retained their nuclei and had smaller numbers of keratohyalin-like granules. Basal cell keratins (CK 5 and 14) and those of hyperproliferation (CK 6 and 16) were consistently found in all epithelia. Furthermore, simple epithelial keratins (CK 18 and 19) were variably expressed by cells from different oral origins. In epithelial cells from the alveolar mucosa, CK 13 and 19 formed major bands, which correlates with their expression in vivo. In contrast, these polypeptides were either absent or formed minor bands in extracts of gingival and hard palatal cells. Although in small quantities, keratins of terminal differentiation (CK 1, 2, 10 and 11) were detected in gels prepared from palatal epithelia. This expression correlates with the higher morphological differentiation of these cells in this model. The model is of interest for studies of epithelial differentiation, as the differentiation markers of keratinized epithelia (CK 1 and 10) were expressed by cells from palatal origin, and those of non-keratinized epithelia (CK 4, 13 and 19) were prominent in cells from alveolar mucosal origin.     

Expression of different keratins in salivary gland tumours

Twenty-four salivary gland tumours (six pleomorphic adenomas, two myoepitheliomas, five basal cell adenomas, six adenoid cystic carcinomas and five polymorphous low grade adenocarcinomas) were investigated by an immunocytochemical technique using monoclonal antibodies against cytokeratins (CKs) 7, 8, 10, 13, 14, 18 and 19. The luminal cells of ductal structures of the tumours reacted with all the CKs studied except for CK 13 and CK 10 and sometimes CK 14, showing an immunoprofile comparable to that of the intercalated segment of a normal salivary gland. The outer cells of the ducts rarely stained with CK 14, confirming that full differentiation of the myoepithelial cells is seldom achieved in tumours. Considerations were made regarding the intriguing expression of CK 14, the heterogeneous expression of CKs in the modified myoepithelial cells and the immunoprofile of the polymorphous low-grade adenocarcinoma.     

Cytokeratin profile of the junctional epithelium in partially erupted teeth

This study uses cytokeratins (CK) as markers to investigate the phenotype of the junctional epithelium (JE) in partially erupted human teeth. The gingival samples, which were clinically healthy, were carefully dissected from the teeth. Cryostat sections were cut for histological staining, immunofluorescence microscopy and gel electrophoresis. Cytokeratins were extracted after microdis-section. The basal and suprabasal epithelial cell markers, cytokeratins 4, 5, 13, 14 and 19 were detected with specific monoclonal antibodies. They showed that the junctional epithelium in erupting teeth has a complex topography. The cytokeratin immunohistochemical profile distinguished between the primary junctional epithelium (CK 5, 14 and 19 in basal and suprabasal cells and CK 13 faintly stained throughout the suprabasal layers) and the adjacent epithelium that had the same cytokeratin profile as the sulcular epithelium (CK 5, 14 and 19 in basal cells and CK 4 and 13 intensively stained in the suprabasal cells). Extraction, two-dimensional electrophoresis and western blotting showed that this transitional JE during eruption also contained CK 6, 16 and perhaps CK 4. Thus, the JE in erupting teeth shows patterns of CK distribution that are very similar to that of developing oral epithelia.     

Clear cell odontogenic tumor in the mandible: report of a case with duct-like appearances and dentinoid induction

A case of clear-cell odontogenic tumor with unusual histological features is presented. A 61-year-old Japanese man was admitted because of swelling of the left premolar-molar region of the mandible. Radiological examination revealed a multilocular radiolucency with irregular margins. Histological examination of the resected specimen showed infiltrative proliferation of both clear and eosinophilic cells into the adjacent soft tissue without encapsulation, suggesting the malignant potential of the tumor. The tumor cells sporadically formed cystic lesions. In addition, several tumor cell nests showed duct-like characteristics, and many eosinophilic dentin-like structures were attached to the tumor cell nests, suggesting the potential for epithelial-mesenchymal induction. Histochemically, the clear tumor cells possessed cytoplasmic glycogen granules. Both clear and eosinophilic tumor cells showed positive immunoreactivities for cytokeratin 19, epithelial membrane antigen and filaggrin, indicating an odontogenic epithelial origin.     

Immunohistochemical evaluation of intermediate filament proteins in squamous papilloma and oral verrucous carcinoma

OBJECTIVE: Cytokeratins (CKs) are the intermediate filament proteins of the epithelium cells, which have become important markers of normal and abnormal cell differentiation. The goal of the present study was to investigate the expression pattern of CK 10, 13, 14 and 16 in oral verrucous carcinoma (OVC) and oral squamous papilloma (OSP). MATERIAL AND METHODS: Formalin-fixed paraffin-embedded sections from eight cases of each lesion were assessed. Immunohistochemistry was carried out using streptoavidin-biotin complex method. RESULTS: In OVC, CK 10 was expressed in suprabasal to superficial layers whereas in OSP mainly in superficial layer. CK 13 was detected in prickle and superficial cells in most cases of OVC and in suprabasal to superficial cells of OSP. All the cell layers of OVC reacted positively for CK 14 while basal and suprabasal layers of OSP were more pronounced for CK 14. Finally, CK 16 was observed in suprabasal to superficial layer in OVC and the majority cases in OSP showed only superficial reactive cells. CONCLUSIONS: CK 10, 13, 14 and 16 immunohistochemical profile emphasis the biological behavior of the studied lesions and confirm the use of these proteins as markers of differentiation.     

Reactive pocket epithelium in untreated chronic periodontal disease: possible derivation from developmental remnants of the enamel organ and root sheath

The pathological lining epithelium of destructive periodontitis was studied by analysis of the expression of intermediate filament proteins in biopsies of untreated advanced periodontitis. The cytokeratin (CK) pair 8/18 characteristic of simple epithelia was expressed consistently in a distribution pattern confined to the reactive pocket epithelium. The pattern of CK8/18 expression was complex with two broad presentations evident. In two-thirds of the advanced disease biopsies, the entire pathological lining epithelium was strongly reactive for both CK8 and CK18. In the remainder, the more superficial lining epithelium was mixed with foci of reactive and unreactive cells, with the deeper epithelium uniformly reactive. Only occasional highly localised reactivity for the simple keratins (CK8/18) was found in the lining epithelia of biopsies from minimally inflamed periodontal tissues. The pathological lining epithelium of advanced periodontitis was further characterised by the co-expression in basal layers of CK14, and of CK13 but not CK4, which are characteristic of suprabasal layers of stratified squamous epithelia. Cytokeratin 17, a marker of high turnover and migrating epithelial cells was extremely variable with no clear association between expression pattern and location of the epithelium ordisease status. There was no reactivity for CK10/11 typical of cornifying cells nor of vimentin, the characteristic intermediate filament of mesenchymal cells. The intermediate filament protein profile of the reactive lining epithelium was indistinguishable from the reactive epithelium present in three of five biopsies of periapical granulomas containing hyperplastic epithelium from activation of the developmental remnants of Hertwig's sheath, known as the cell rests of Malassez. The data reported are compatible with a contribution by remnants of developmental epithelium, including the reduced enamel epithelium and the cell rests of Malassez, to the reactive lining epithelium of the subgingival pocket in the pathogenesis of chronic periodontitis.     

人牙龈结合上皮、口腔龈上皮及沟内上皮中细胞角蛋白的表达

目的 检测人牙龈上皮的细胞角蛋白(CK)谱，探讨结合上皮(JE)与口腔龈上皮(OE)、沟内上皮(SE)的不同。方法 5例人磨牙及前磨牙牙龈颊舌向石蜡切片，采用免疫组化SP法行CK5／6、7、8／18、10／13、16、17、19、20染色。结果 CK7、17在3种上皮中均无表达；CK5／6、20在3种上皮的基底上层(尤其是近表层)为弱阳性及阳性表达，基底层无表达；CK10／13、16在JE全层均有表达，在OE和SE仅限于基底上层，其中CK10／13为强阳性，CKl6为弱阳性及阳性；CK19在JE全层强阳性，在OE和SE仅限于基底层，JE和SE分界明显；CK8／18与CK19相似，只是表达较弱，近基底层的基底上层也有少量表达。结论JE是一种不同于OE和SE的特殊低分化上皮，CK19可作为JE的特征性标记物区别于OE和SE，CK10／13、16可用于体外培养的上述3种细胞的鉴别。     

A immunohistochemical study of the peripheral ameloblastoma

AIM: Peripheral ameloblastoma (PA) is a rare variant of ameloblastoma occurring in the extraosseous region. With regard to the histogenesis of the tumor, two major sources of origin are considered: odontogenic epithelial remnants and the gingival epithelium. In this study, we examined the immunohistochemical profiles of cytokeratins (CKs) and Ki-67 labeling index (LI) of PAs, and discuss the histogenesis and the biologic behavior of the PA. MATERIALS AND METHODS: Eight cases of PA were retrieved from the pathology files of 212 cases of ameloblastoma that had been registered at our hospital. Immunohistochemical staining was performed in seven cases using monoclonal antibodies of six CKs (7, 8, 13, 14, 18, and 19) and Ki-67. RESULTS: All cases of PA expressed CK13, 14, and 19. CK18 was positive staining in six cases, and CK8 in five cases. This staining pattern was similar to that in intraosseous ameloblastomas (IAs). The mean of Ki-67 LI of PAs (1.91%) was significantly lower than that of IAs (4.82%) (P = 0.002). CONCLUSION: We consider that the PA originates from odontogenic epithelial remnants rather than from the gingival epithelium, and the Ki-67 LI of the tumor is a good prognostic indicator.     

Expression of cytokeratins in human enamel organ

Cytokeratin (CK) is a filament which plays a central role in epithelial tissue and, like the polypeptides of intermediate filaments in general, shows a high degree of tissue specificity. The CK expression patterns of odontogenic epithelia are still poorly described. We studied the distribution of individual CK polypeptides in the human enamel organ at bell stage and in remnants of the dental lamina. Our immunohistochemical study showed that epithelial cells stained for CKs 7, 13, 14 and 19 with slight changes in their pattern during the differentiation phase of odontogenesis. There was negative staining for all other CK polypeptides tested (CKs 8, 10, 16, 17 and 18). Most of the CKs in the enamel organ epithelia did not show differences related to the stage-specific state of differentiation, except for CKs 14 and 19 at the inner enamel epithelium. A strong label for CK 14 was present at the inner dental epithelium at early bell stage, and this was substituted by CK 19 at the late bell stage when the ameloblasts were fully differentiated.     

Clear cell odontogenic carcinoma of the maxilla: clinical,histological and immunohistochemical features of a case

Clear cell odontogenic carcinomas are rare, aggressive tumours, most of which have been reported in the mandible of female patients. Here we report a clear cell odontogenic carcinoma of the maxilla in a 55-year old male, which was predominantly composed of sheets of polygonal cells with clear cytoplasm, admixed with smaller, eosinophilic cells, which were palisaded peripherally. The peripheral tumour cells expressed cytokeratins 7, 14 and, focally, CK19, but the clear cells were negative for all markers tested. An extended maxillectomy was performed. There was local recurrence after six years, which was treated with radiotherapy, and after a further year the patient is alive with no evidence of further disease.     

细胞角蛋白18及其基因在牙源性角化囊肿衬里上皮中表达的意义

目的检测细胞角蛋白18（CK18）及其基因在牙源性角化囊肿（OKC）衬里上皮中的表达。方法选取32例OKC的衬里上皮组织,分别进行CK18、CK8和CK19单克隆抗体的免疫组织化学染色。对其中12例使用RT- PCR法检测CK18 mRNA,观察其在衬里上皮中的表达;同时使用CK18基因探针进行原位杂交,检测CK18 mRNA在衬里上皮细胞层的定位表达。结果在免疫组织化学染色中, 17例CK18蛋白在OKC衬里上皮的表层细胞层表达为弱阳性;27例CK18蛋白在棘细胞层上层染色为阳性;14例CK18蛋白在棘细胞层染色为阳性;所有标本基底细胞层染色呈阴性。RT- PCR法检测见4例CK18 mRNA表达为强阳性,8例表达为弱阳性。原位杂交法检测见8例CK18 mRNA在棘细胞层和棘细胞层上层呈阳性,4例在上皮基底细胞层和角化层呈阳性。CK8蛋白在所有32例OKC衬里上皮基底细胞层均有表达。CK19蛋白在23例OKC衬里上皮表层均有表达。结论CK18在OKC衬里上皮的表达由基底细胞层向棘细胞层迁移,CK18蛋白免疫组织化学染色阳性表达与CK18 mRNA原位杂交法阳性表达不同,提示CK18可能与衬里上皮的增殖活性有关,OKC衬里上皮中可能存在CK18蛋白和CK18 mRNA表达的调控因子。     

牙源性上皮性联合瘤的临床病理和角蛋白表达研究

目的：研究4例牙源性上皮性联合瘤的临床病理和角蛋白免疫组化表达。方法：4例牙源性上皮性联合瘤均来源于武汉大学口腔医学院病理学教研室，10％福尔马林溶液固定，常规制片HE染色，免疫组化SP法检测肿瘤组织中CKl0、CKl0和13、CKl8和8、CKl9蛋白的表达。结果：全部4例中均显示牙源性腺样瘤的典型组织学特点，牙源性钙化上皮瘤样区大小不等，1例中的CEOT区为主要成分，CKl9呈阳性表达。结论：报告四例牙源性腺样瘤和牙源性钙化上皮瘤构成的牙源性上皮性联合瘤，其中一例为罕见的以牙源性钙化上皮瘤成分为主。