Immunohistochemical study of sensory nerve formations in human glabrous skin.

The sensory nerve formations (or corpuscles) of normal human glabrous skin from hand and fingers, obtained by punch biopsies, were studied by the streptavidin-biotin method using monoclonal antibodies directed against neurofilament protein (NFP), S-100 protein, glial fibrillary acidic protein (GFAP), cytokeratins, and vimentin. NFP immunoreactivity (IR) was observed in the central axons of most sensory formations, while S-100 protein IR was restricted to non-neuronal cells forming the so-called inner cells core or lamellar cells. Furthermore, vimentin IR was found in the same cells of Meissner's and glomerular corpuscles. None of the sensory nerve formations were stained for GFAP or keratin. The present results suggest that the main nature of the intermediate filaments of the non-neuronal cells of sensory nerve formations from human glabrous skin is represented by vimentin and not by GFAP. Thus, our findings suggest that lamellar and inner core cells of SNF are modified and specialized Schwann cells and not epithelial or perineurial derived cells.     

Immunohistochemical study of cat Pacinian corpuscles: co-localization of vimentin- and S-100 protein-like in the inner core

The presence of vimentin and S-100 protein in cat Pacinian corpuscles of cat mesentery has been investigated immunohistochemically (streptavidin-biotin method) using monoclonal antibodies. A positive reaction for both vimentin- and S-100 protein-like was found only in the lamellae of the inner core. The presence of vimentin and the co-expression of vimentin/S-100 protein-like in sensory corpuscles is reported for the first time. The authors discuss the origin of the inner core and capsule of sensory corpuscles on the basis of their immunohistochemical characteristics.     

Immunohistochemical study of Pacinian corpuscles using monoclonal antibodies for neurofilament protein, glial fibrillary acidic protein and S-100 protein

The presence of neurofilament protein (NFP), glial fibrillary acidic protein (GFAP) and S-100 protein has been investigated in Pacinian corpuscles from cat's mesentery by means of immunohistochemical methods. The NFP-like positivity was found in the central axon of the corpuscles; the GFAP- and S-100 protein-like immunoreactivities were shown in the innermost layers of the differentiated cell of the inner core. No positive reaction was detected in the capsule. The authors discuss these findings.     

Intermediate filament expression in non-neoplastic pituitary cells.

Fifty-one non-neoplastic human pituitary glands, including examples with Crooke's hyalinization or amyloidosis, were examined by an immunoperoxidase method using antibodies to keratin, vimentin, neurofilaments (NFs), glial fibrillary acidic protein (GFAP), desmin, actin, S-100 protein and a variety of pituitary hormones. It was confirmed that most of the epithelial cells in the pituitary gland express keratin immunoreactivity. These cells included endocrine cells in the anterior lobe, endocrine cells and squamous metaplastic cells in the pars tuberalis, columnar and ciliated epithelia forming follicular structures and salivary-type epithelium in the pars intermedia, and anterior lobe cells infiltrating the posterior lobe. This study also demonstrated that keratin and NFs may be co-expressed in endocrine cells in the pituitary anterior lobe, that keratin, vimentin and GFAP may be co-expressed in the epithelial cells forming cyst-like follicle in the pars intermedia, and that vimentin and GFAP may be co-expressed in folliculo-stellate cells and pituicytes. In addition, the GFAP and S-100 protein-negative high columnar epithelium in the pars intermedia tended to be positive for adrenocorticotropic hormone and melanocyte stimulating hormone, while the low columnar epithelium with the co-expression of GFAP and S-100 protein was negative for pituitary hormones.     

Expression of cytoskeletal proteins in glial cells of dorsal root ganglia

The localization of S-100 protein-, glial fibrillary acidic protein- and vimentin-like immunoreactivity has been studied in dorsal root ganglia of the rat using monoclonal antibodies. A positive reaction for both S-100 protein-like and vimentin-like was found in satellite and Schwann cells. In addition, some large and intermediate sized neurons also result S-100 protein-like immunoreactivity. No positive reaction for glial fibrillary acidic protein-like was observed. The authors discuss these results.     

Granular cell tumors: evidence for heterogeneous tumor cell differentiation

Eighteen granular cell tumors from various sites were examined with antisera directed against protein S-100, neuron specific enolase (NSE), alpha-1-antichymotrypsin, and alpha-1-antitrypsin, glial fibrillary acidic protein (GFAP), lysozyme, factor VIII-related antigen, myoglobin and vimentin, as well as with a monoclonal antibody (lu-5) directed against a panepithelial marker. The immunocytochemical reaction pattern of the tumors was heterogeneous. The brain and pituitary tumors and one thyroid tumor reacted for alpha-1-antichymotrypsin and alpha-1-antitrypsin, but not for S-100 protein and NSE. However, tumors from other sites showed immunoreactions for S-100 protein and NSE and some also for vimentin. Reactions for alpha-1-antichymotrypsin and alpha-1-antitrypsin were not observed. All other reactions were similarly negative. We conclude that the morphologically homogeneous group of granular cell tumors is biologically heterogeneous.     

Multiple expression of keratins, vimentin, and S-100 protein in pleomorphic salivary adenomas.

Immunohistochemical staining for S-100 protein and the intermediate filaments keratin and vimentin, was made in 41 salivary adenomas. In pleomorphic adenomas, great heterogeneity in the staining, as well as multiple and co-expressions of these proteins were found in the outer tumor cells of tubulo-ductal structures and modified myoepithelial cells, but not in the luminal tumor cells. All the outer tumor cells stained for S-100 protein, 97% for K8.12 keratin and 85% for vimentin. Of these cells, 29% showed multiple expression of K8.12 keratin, vimentin, and S-100 protein, and 17% showed co-expression of K8.12 and S-100 protein. Modified and neoplastic myoepithelial cells showed similar expressions of these proteins to those of outer tumor cells; myoepithelioma cells displayed the most complicated pattern, being positive for KL1, PKK1, and K8.12 keratins, vimentin and S-100 protein. In luminal tumor cells there was a heterogeneous expression of KL1 and PKK1 in 82%, and of KL1, PKK1, and K8.12 in only 14.7%. Based on the immunohistochemical findings obtained with different monoclonal antibodies in pleomorphic salivary adenomas, outer tumor cells may be derived from ductal basal cells and luminal tumor cells from intercalated duct cells.     

Multiple expression of keratins,vimentin, and S-100 protein in pleomorphic salivary adenomas

Immunohistochemical staining for S-100 protein and the intermediate filaments keratin and vimentin, was made in 41 salivary adenomas. In pleomorphic adenomas, great heterogeneity in the staining, as well as multiple and co-expressions of these proteins were found in the outer tumor cells of tubulo-ductal structures and modified myoepithelial cells, but not in the luminal tumor cells. All the outer tumor cells stained for S-100 protein, 97% for K8.12 keratin and 85% for vimentin. Of these cells, 29% showed multiple expression of K8.12 keratin, vimentin, and S-100 protein, and 17% showed co-expression of K8.12 and S-100 protein. Modified and neoplastic myoepithelial cells showed similar expressions of these proteins to those of outer tumor cells; myoepithelioma cells displayed the most complicated pattern, being positive for KL1, PKK1, and K8.12 keratins, vimentin and S-100 protein. In luminal tumor cells there was a heterogeneous expression of KL1 and PKK1 in 82%, and of KL1, PKK1, and K8.12 in only 14.7%. Based on the immunohistochemical findings obtained with different monoclonal antibodies in pleomorphic salivary adenomas, outer tumor cells may be derived from ductal basal cells and luminal tumor cells from intercalated duct cells.     

Morphological and neurochemical diversity of neuronal nitric oxide synthase-positive amacrine cells in the turtle retina

By gently scraping off the surface of the lateral ventricles of adult bovine brains, we obtained sheets containing the ependymal layer and some attached sub-ependymal cells. Explants were cultured in serum-free medium or in two media enriched with 20% fetal calf serum or 20% adult bovine cerebrospinal fluid, and processed for different time intervals from 4 h to 60 days. For characterization of the ependymal cells we used antisera against S-100 protein, vimentin and glial fibrillary acidic protein (GFAP). For comparison, the ependyma of adult bovines and of fetuses from days 60 to 120 post coitum was studied in situ. The adult ependyma consisted of a ciliated, cuboid cell monolayer with short basal processes; it displayed S-100 immunoreactivity but only scarce deposits of vimentin and no GFAP. The fetal ependyma had the appearance of a pseudostratified epithelium with elongated nuclei and basal processes containing S-100 and vimentin from day 80 post coitum and GFAP from day 100 post coitum. In explants, no differences were seen between the three culture media; the ependyma became pseudostratified, developed basal processes and showed increasing amounts of S-100 and vimentin first, and subsequently also GFAP. These changes were concomitant with the onset of mitotic activity in the subependymal layer leading to the production of numerous cells. The morphological and immunocytochemical features of ependymal cells in cultured explants resembled those of fetal ependyma. Our results indicate that the culture of ependymal explants from adult bovine lateral ventricles is an useful model system for morphological and functional studies of the ependyma and for the analysis of cell proliferation in the subependymal layer.     

Morphological characterization of a human glioma cell l ine

A human malignant continuous cell line, named NG97, was recently established in our laboratory. This cell line has been serially subcultured over 100 times in standard culture media presenting no sign of cell senescence. The NG97 cell line has a doubling time of about 24 h. Immunocytochemical analysis of glial markers demonstrated that cells are positive for glial fibrillary acidic protein (GFAP) and S-100 protein, and negative for vimentin. Under phase-contrast microscope, cultures of NG97 showed cells with variable morphological features, such as small rounded cells, fusiform cells (fibroblastic-like cells), and dendritic-like cells. However, at confluence just small rounded and fusiform cells can be observed. At scanning electron microscopy (SEM) small rounded cells showed heterogeneous microextentions, including blebs and filopodia. Dendritic-like cells were flat and presented extensive prolongations, making several contacts with small rounded cells, while fusiform cells presented their surfaces dominated by microvilli.     

Antigenic profile of the human lacrimal gland.

The antigenic profile of 13 normal formalin-fixed, paraffin-embedded human main and accessory lacrimal glands, biopsied from patients aged 11 to 78 years, was studied using a panel of 27 polyclonal and monoclonal antibodies. Secretory cells of lacrimal acini reacted with antibodies to S-100 protein and simple epithelium-type cytokeratins CK 7, CK 8, CK 18, and CK 19. Their luminal membranes were labeled with antibodies to carcinoembryonic antigen, epithelial membrane antigen, and epithelial glycoproteins recognized by Ber-EP4. Myoepithelial cells were often immunopositive for S-100 protein, vimentin, glial fibrillary acidic protein (GFAP), and alpha-smooth muscle actin. More rarely, they reacted with antibodies recognizing CK 5, CK 13, and CK 14, which consistently labeled the basal cells of lacrimal ducts. Unlike myoepithelial cells, basal ductal cells were immunopositive for CK 7, CK 8, CK 18, and CK 19. In main excretory ducts, dendritic melanocyte-like cells co-expressing vimentin and S-100 protein intermingled with ductal epithelial cells. The luminal cells of lacrimal ducts basically paralleled secretory cells in their antigenic profile, although they lacked Ber-EP4 and were immunopositive for CK 4. Antibodies to neuron-specific enolase and synaptophysin reacted with nerve fibers among negatively reacting secretory acini. This antigenic profile closely parallels that of salivary glands and provides a basis for studies of lacrimal gland pathology.     

Selected immunohistochemical markers in stromal neoplasms of the gastrointestinal tract.

We studied immunohistochemical reactions to vimentin, desmin and protein S-100 in 43 cases of stromal tumors of the gastrointestinal tract. The material studied included: 1 esophageal tumor, 18 gastric tumors, 19 small intestinal tumors and 5 colonic tumors, classified in 13 cases as benign and in 30 cases as malignant neoplasms of various degree of malignancy. Mean age of the patients was 58.9 years. A positive reaction to vimentin was found in 37 cases, a negative reaction concerned an esophageal tumor, two benign tumors (gastric and small intestinal) and three malignant tumors (gastric and two small intestinal). A positive reaction to desmin was detected in an esophageal tumor and in nine gastric tumors. Only one benign small intestinal tumor and three benign colonic tumors showed a positive reaction to desmin. Protein S-100 was found in an esophageal tumor and in 7 out of 18 gastric tumors and in 12 out of 24 intestinal tumors. Coexpression of vimentin and desmin was found in 8 gastric tumors, only in one small intestinal tumor and in three colonic tumors. Three gastric tumors showing both these reactions were all benign. Coexpression of desmin and protein S-100 was found in 7 out of 43 tumors of the alimentary tract. In six cases these tumors were benign. Basing on the results we may say that the presence of these antigens reflects the degree of differentiation of gastrointestinal stromal tumors of the gastrointestinal tract, though it does not allow to choose unequivocally conclusions as to their histogenesis.     

Intermediate filament expression in pituitary adenomas.

Seventy-five formalin-fixed and 18 alcohol-fixed pituitary adenomas were studied immunohistochemically using antibodies to keratin, vimentin, neurofilaments (NFs), glial fibrillary acidic protein, desmin, actin, S-100 protein and a variety of pituitary hormones. The pituitary adenoma cells were positive for keratin, vimentin and NFs (68 kDa and 160 kDa) and in a few instances there was co-expression of these three types of intermediate filaments (IMFs). The pattern of keratin-specific staining showed diffuse cytoplasmic or patchy paranuclear reactivity and of NF- or vimentin-specific staining showed fibrillar or patchy paranuclear reactivity. The patchy staining seemed to decorate the fibrous body. There was no correlation between the distribution of IMFs and pituitary hormones in pituitary adenomas except that melanocyte-stimulating-hormone-positive reactivity was limited to the NF-positive adenomas. The pattern of IMF staining did not depend on hormone production in adenomas.     

Immunohistochemical localization of S-100 protein subunits (alpha and beta) in dorsal root ganglia of the rat

The distribution of S-100 protein and their subunits (alpha and beta) in lumbar dorsal root ganglia of adult rat was investigated immunohistochemically using monoclonal antibodies against the S-100 protein, alpha-subunit and beta-subunit of S-100 protein. The conventional S-100 protein antibody stained both neurons (large and intermediate in size; 20.3% and 41 +/- 3.2 microns of diameter) and glial cells (satellite cells and Schwann cells). The immunoreaction for the alpha-subunit was observed in the perikarya of some large and intermediate sized neurons (17.2%, 45.6 +/- 6.1 microns of diameter), satellite cells and Schwann cells, whereas the beta-subunit immunoreactivity was found principally in glial cells, and in a scarce number of large and intermediate sized neurons (2.8%, 43.3 +/- 5 microns of diameter) Our results demonstrate that a subpopulation of large and intermediate sized neurons of lumbar DRG contain alpha- and beta-subunits of S-100 protein, being alpha-subunit predominant. Furthermore, the satellite glial and Schwann cells contain also the two subunits but mainly beta-subunit. These data confirm previous studies about the presence of S-100 protein in neurons of the central and peripheral nervous system.     

Immunohistochemical studies of S-100 protein alpha and beta subunits in adenoid cystic carcinoma of salivary glands

Immunohistochemical studies were performed to explore the distribution of S-100 protein and its alpha, beta subunits in 76 adenoid cystic carcinomas (ACC) of the salivary glands. Histopathologically. ACC was divided into cribriform, tubular, basaloid and trabecular types which could be mixed in the same tumor. S-100 protein was usually positive in tumor cells forming cribriform structures; foci of strongly positive tumor cells were also distributed in the luminal layer of tubular structures, and in areas transitional between cribriform and tubular patterns. S-100 alpha staining was confined to some tumor cells in cribriform areas, to luminal tumor cells in tubular structures and to few tumor cells in basaloid structures. S-100 beta reaction was usually localized to luminal surfaces in a fine granular pattern in tubular and microtubular structures in a distribution somewhat similar to that in the normal salivary gland. Great heterogeneity in the immunohistochemical distribution of S-100, S-100 alpha and S-100 beta proteins was found in the various histologic types of ACC and the pattern was different from that seen in pleomorphic adenomas. It is possible that the ACC tumor cells positive for S-100 protein may be closely related to true or modified myoepithelial cells.     

Immunohistochemical approach to the study of the cat carotid body

The mammalian carotid body contains a number of different cell types which are not always easy to identify in routine histological sections. We have devised a battery of immunohistochemical tests which overcome this difficulty and offer the possibility of performing routine morphometric analyses of the response of the organ to various pathological processes in paraffin-embedded sections. The type 1 cells can be identified on the basis of their reaction with neuronal specific enolase, whilst type II cells react with antibodies to S-100 protein. Schwann cells do not react with S-100 antibodies but do so with antibodies to glial fibrillary acidic protein; nerve fibres can be identified by their reaction to neurofibrillary protein.     

Bowes human melanoma cell line. An immunocytochemical study

Bowes human melanoma cell line was investigated immunocytochemically to localize S-100 protein, HMB-45 and intermediate filament proteins. The majority of the cells showed strong positive staining with antibodies directed against S-100 protein, HMB-45 and vimentin filaments. Antibodies directed against the other cytoskeletal proteins failed to show any reactivity. These findings suggest that this transformed cell line does not dedifferentiate in culture and continues to express the specific antigens of human melanoma cells. Thus, Bowes cell line provides a useful model for studying the cellular biology and pathology of malignant melanoma.     

Expression of immunoreactivity for Ca-binding protein, spot 35 in the interstitial cell of the rat pineal organ

Summary In the rat pineal organ numerous stellate cells exhibited intense immunoreactivity for calcium-binding spot 35 protein. Because of their peculiar shape and ultrastructure, identical to those of intrapineal S-100-immunoreactive cells, the spot 35-immunoreactive stellate cells were identified as the interstitial cells. The comparison of the morphology and population density of spot 35-, S-100-, and GFAP (glial fibrillar acidic protein)-immunoreactive cells, suggests that spot 35-immunoreactive cells represent a major subpopulation of the interstitial cells, all of which are S-100-immunoreactive and generally considered to be of glial nature, while GFAP-immunoreactive cells represent a minor subpopulation of the interstitial cells located in the proximal part close to the pineal stalk. This is the first report describing the occurrence of the calcium-binding protein in cells of glial nature.To whom all correspondence should be sent.     

Coexpression of Vimentin, Cytokeratin and S-100 In Monomorphic Adenoma of Salivary Gland; Value of Marker Studies In the Differential Diagnosis of Salivary Gland Tumours

An unusual coexpression of glial fibrillary acid protein (GFAP), keratin and vimentin occurs in pleomorphic adenoma of salivary gland. We designed this study to see if coexpression of the markers was also present in monomorphic adenoma of the salivary gland and whether monomorphic adenoma could be distinguished from other salivary gland tumours by marker studies. Immunocytochemical markers were used on fine needle aspiration samples from four cases of monomorphic adenoma, two cases of oncocytic adenoma, three cases of adenoid cystic carcinoma and four cases of pleomorphic adenoma. While positivity for cytokeratin, vimentin and S-100 was consistently found in all cases of monomorphic adenoma, only cytokeratin was expressed in adenoid cystic carcinoma. In pleomorphic adenoma, GFAP, cytokeratin and vimentin were coexpressed while in cases of oncocytic adenoma none of the markers was localized. Thus, it appears that by using a combination of GFAP, cytokeratin, vimentin and S-100 a distinction between these neoplasms may be possible. However, a larger study is needed to establish the usefulness of this approach.     

Postnatal development of the interstitial cells (palisade cells) of the pars intermedia in the cat pituitary gland. An immunocytochemical and ultrastructural study.

The postnatal development of the interstitial agranulated cells (so-called palisade cells) of the pars intermedia in the cat was investigated immunocytochemically and at the ultrastructural level. Since the first postnatal days, a strong vimentin immunoreactivity and a weaker S-100 protein immunoreactivity were detected in the marginal cells lining the pituitary cleft and in the interstitial bipolar cells located within the pars intermedia. No glial fibrillary acidic protein cells have been found in the pars intermedia of any of the animals studied. This immunocytochemical pattern was maintained throughout the postnatal development. Ultrastructurally these cells showed a vast number of cytoplasmic filaments and well-developed junctional complexes. Secretory granules were never seen. In older animals they lined microcavities and microchannels where they project microvilli and present pinocytotic vesicles on their apical surface. No transitional forms between these cells and granulated secretory cells were found. There is a large number of axons and synaptic endings in contact with the granulated secretory cells. From our findings we guess that palisade cells are not a glial derivative, but they may share a common origin with secretory granulated cells.