Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Epithelioid Cells”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1985

Differentiation of granuloma cells (epithelioid cells and multinucleated giant cells): a morphometric analysis. Investigations using the model of experimental autoimmune (anti-TBM) tubulo-interstitial nephritis.

Morphometric analysis disclosed distinct differences between blood monocytes, tissue monocytes (i.e. immature macrophages), epithelioid cells and multinucleated giant cells as well as phagocytic macrophages (i.e. mature macrophages) in the granuloma model of autoimmune (anti-TBM) tubulo-interstitial nephritis. The numerical density of lysosomes decreased slightly in tissue monocytes compared with blood monocytes but showed a pronounced increase during the formation of epithelioid cells. The lysosomal compartments of epithelioid cells and multinucleated giant cells resembled each other very closely, but the giant cells obviously produced additional lysosomes of small diameter (80-120 nm). Phagocytic macrophages displayed a total numerical density of lysosomes similar to that of tissue monocytes but the mean diameter of the lysosomes was markedly greater. Thus the volume density of lysosomes was highest in phagocytic macrophages. The blood monocytes exhibited the smallest lysosomal compartment. In tissue monocytes, epithelioid cells, and multinucleated giant cells the volume densities of the lysosomes were greater than in blood monocytes and remained relatively constant because the increase in numerical density was counterbalanced by a decrease in mean granule diameter. We found only minor differences in mitochondrial volume densities among the five cell populations. The shape of the mitochondria, however, changed steadily from short rotational ellipsoids in the blood monocytes to rather elongated and slender bodies in the multinucleated giant cells. The results suggest that epithelioid cells and multinucleated giant cells are active cells which may contribute by their specific performances, to the immunologic microenvironment of the granuloma.

Animals↗
PubMed2000

Hyalinized Uterine Mesenchymal Neoplasms with HMB-45-Positive Epithelioid Cells: Epithelioid Leiomyomas or Angiomyolipomas? Report of Four Cases.

We present 4 cases of uterine mesenchymal tumors that were located mostly in the myometrium in middle-aged women. Grossly the tumors vaguely resembled conventional leiomyomas. All tumors were extremely hyalinized. The tumor cells were remarkable because of their large size and epithelioid shape. They occurred singly or more often in variously sized clusters with pericellular clear spaces looking like a halo. The extracellular matrix often formed lacunae around the neoplastic cells. The lacunar type of growth was somewhat reminiscent of immature cartilage. In some places the cells lined up in vague cord-like structures. The epithelioid cells often grew within vessel walls and subendothelially, simulating angioinvasion. In 2 cases there were periodic acid-Schiff (PAS)-positive, needle-shaped crystalloids in the cytoplasm of the tumor cells. No atypias and no mitoses were found in any of the 4 tumors. Mucicarmine stain was negative in all cases. Immunohistochemically the tumor cells were negative for cytokeratins, synaptophysin, chromogranin, epithelial membrane antigen (EMA) S-100 protein, and inhibin. They were instead strongly positive for smooth muscle actin, desmin and HMB-45. All patients are disease free after a 1-4-year follow-up. Int J Surg Pathol 8(4):323-328, 2000

Journal Article↗
PubMed1982

The origin, morphology, and function of epithelioid cells.

Epithelioid cells are cells of the mononuclear phagocyte system found in certain granulomas mainly associated with intense immunological activity. These cells show little phagocytic activity. In certain experimental granulomas such as those produced in guinea pigs sensitive to zirconium, and at sites of intense inflammatory reaction in man, they may contain varying amounts of rough endoplasmic reticulum ("secretory" epithelioid cells). In other situations such as tuberculoid leprosy and in some cases of sarcoidosis they may have the appearance of activated macrophages or take on a multivesicular appearance ("vesicular" epithelioid cells). It is suggested that "vesicular epithelioid cells could develop from "secretory" epithelioid cells by a process of degeneration. In studies comparing granulomas induced in lymph nodes draining the site of intradermal injection of mycobacteria, epithelioid cell granulomas were produced with BCG vaccine, whereas, the granulomas induced by Mycobacterium leprae contained undifferentiated macrophages that contained phagocytosed organisms. The BCG granulomas were in addition characterised by fibroblast infiltration, the presence of collagen and resolution by fibrosis. M. leprae granulomas showed little evidence of fibroblastic activity. Biochemical studies confirmed that BCG granulomas formed new collagen in vitro, whereas this did not take place with M. leprae granulomas. It is suggested that epithelioid cells could play an important role in fibrosis possibly by the secretion of a fibroblast activating factor.

Animals↗
PubMed1989

Spindle cell and epithelioid cell nevi with atypia and metastasis (malignant Spitz nevus).

We report on the clinical and pathologic features of 32 lesions diagnosed as malignant spindle cell and epithelioid cell nevus (S&E nevus). Because of the clinical or initial histopathologic diagnosis of malignant melanoma, six patients had lymph node dissection. Three of these patients also had an enlarged lymph node. In all six cases, metastatic spindle or epithelioid cells were found in at least one of the resected lymph nodes. Of the 30 patients with follow-up information, including all six patients with lymph node metastases, all are alive and well. No recurrences or further metastases have been found. On histopathologic reevaluation, all the lesions had features of S&E nevi. Study of these cases suggests that although some lesions with features of S&E nevi may involve local lymph nodes, widespread metastases do not result.

Humans↗
PubMed1985

[The Spitz nevus. Spindle cell and/or epithelioid cell nevus--a histological analysis of 652 tumors].

652 Spitz' nevi have been histologically analysed and separated into epidermal and dermal changes. There are similarities between Spitz' nevus and melanocytic nevus. 44.9% of the examined Spitz' nevi consist of spindle cells only, 34% of spindle as well as epithelioid cells, and 21% of epithelioid cells only. We are going to discuss the difficulties in histological examination; more or less important signs are differentiated in detail. In some cases, Spitz' nevus will remain a somewhat dubious and disturbing tumor.

Adolescent↗
PubMed1989

Spitz nevus (large spindle cell and/or epithelioid cell nevus). Age-related involvement of the suprabasal epidermis.

The Spitz nevus (large spindle and/or epithelioid cell nevus) is a benign acquired melanocytic tumour found predominantly in children and adolescents. Depending on the architecture (junctional, compound, dermal) and cytology (predominance of spindle or epithelioid cells, or presence of both cell types) several variants have been distinguished. A histological feature occasionally leading to diagnostic difficulties is the involvement of the suprabasal epidermis. The present study details the occurrence of intraepidermal involvement (pagetoid spread, nesting of cells, trans-epidermal elimination) according to the age of the patients. 89 cases of Spitz nevus were reviewed. There were 19 compound Spitz nevi with evidence of epidermal involvement, 56 cases of compound Spitz nevi without evidence of epidermal involvement and 14 cases of dermal Spitz nevi. The epidermal involvement mainly consisted of nesting of nevus cells above the basal cell layer, 9 cases clearly showing evidence of transepidermal elimination of cell nests. Upward spread of single melanocytes (pagetoid spread) was minimal and always associated with nesting or trans-epidermal elimination. The mean age of patients was significantly lower in the group of compound nevi with intraepidermal involvement (7.16 +/- 4.52 years), than in the group of compound nevi without epidermal involvement (13.18 +/- 8.88 years). The age of the latter group was significantly lower than the group of pure intradermal nevi (30.14 +/- 11.25 years). Thus, involvement of the suprabasal epidermis is not a feature of Spitz nevi in adults; in such a case the diagnosis of malignant melanoma should be considered.

Adolescent↗
PubMed1980

Desmoplastic nevus: a distinct histologic variant of mixed spindle cell and epithelioid cell nevus.

From a series of 75 cases of mixed spindle cell and epithelioid cell nevi, 14 were designated as desmoplastic nevi. Junctional activity, theque formation, and pigmentation were uncommon features. As a result, desmoplastic nevi may be confused with a variety of fibrohistiocytic lesions. Well defined intranuclear invaginations of cytoplasm occurred in 12 cases, and were helpful in differentiating desmoplastic nevi from these lesions. Desmoplastic malignant melanoma must also be considered in the microscopic differential diagnosis, but distinguishing features of desmoplastic melanoma include the presence of preexisting lentiginous melanoma, and necrosis of tumor cells and collagen. Desmoplastic nevus was compared to the ordinary variants of mixed spindle cell and eipthelioid cell nevus in an attempt to define etiologic factors responsible for a desmoplastic reaction. No satisfactory explanation could be found since the clinical variables examined were not statistically different.

Adolescent↗
PubMed1998

Eosinophilic globules in spindle cell and epithelioid cell nevi: composition and possible origin.

The presence of eosinophilic globules has been described as a helpful sign for the histologic differentiation of Spitz's nevus from malignant melanoma. The origin of these bodies is not clear, and they have been likened to Civatte or colloid bodies of lichen planus. This would suggest that they might originate from degenerating keratinocytes or melanocytes or both. These eosinophilic globules and the colloid bodies of lichen planus have been reported to be similar in that they both stain positively for type IV collagen and laminin. These previous reports have failed to include, or have not emphasized, the staining for keratin that separates these two bodies. We stained 10 spindle cell and epithelial cell (S&E) nevi for S-100 protein, keratin, vimentin, type IV collagen, and laminin. In all 10 cases of S&E nevi, the eosinophilic globules showed a positive reaction for type IV collagen and laminin and a negative reaction for keratin, S100 protein, and vimentin, unlike the colloid bodies of lichen planus, which showed a negative reaction for type IV collagen and laminin and also a strong positive reaction for keratin. These results suggest that the eosinophilic globules of Spitz's nevi are basement membrane material, perhaps synthesized by either basal cells, melanocytes or both, and are not degenerated basal cells or melanocytes.

Adolescent↗
PubMed1985

[The Spitz nevus. Spindle cell and/or epithelioid cell nevus--a clinical analysis of 652 tumors].

We report on clinical aspects of 652 Spitz' nevi. In 42.9% of the cases, this tumor has been observed in people over 19 years. The female sex with 61.6% was much more concerned than the male sex. Most frequently, the lower extremities were affected (30.1%). The clinical diagnosis of Spitz' nevus could be definitely made in only 13.9% of the cases. We are going to discuss the very variable clinical picture of Spitz' nevus.

Adolescent↗
PubMed2006

Comparative genomic hybridization study of perivascular epithelioid cell tumor: molecular genetic evidence of perivascular epithelioid cell tumor as a distinctive neoplasm.

Perivascular epithelioid cell tumor (PEComa) is a neoplasm composed chiefly of HMB-45-positive epithelioid cells with clear to granular cytoplasm and a perivascular distribution. Such tumors have been reported in different organs under a variety of designations. The cytogenetic features of these neoplasms have not been well studied. We collected 9 tumors (5 of kidney, 1 of prostate, 1 of urinary bladder, 1 of the pelvic cavity soft tissue, and 1 of uterus) from 8 patients, including one patient with tuberous sclerosis complex. The paraffin blocks of tumor tissue were submitted for comparative genomic hybridization analyses. Gross chromosomal aberrances were observed in all cases. The frequent imbalances were losses on chromosome 19 (8 cases), 16p (6 cases), 17p (6 cases), 1p (5 cases), and 18p (4 cases) and gains on chromosome X (6 cases), 12q (6 cases), 3q (5 cases), 5 (4 cases), and 2q (4 cases). The frequent deletion of 16p in which TSC2 gene is located indicates the oncogenetic relationship of PEComas with angiomyolipoma as a TSC2-linked neoplasm. From a molecular genetic perspective, the recurrent chromosomal alterations in both renal and extrarenal tumors further support the concept of PEComa as a distinctive tumor entity regardless of anatomic location.

Adolescent↗
PubMed1988

[Immunohistochemical characterization of epithelioid cells].

Focally aggregated epithelioid cells and granulomatous epithelioid cell reactions of different genesis were investigated immunohistochemically by means of PAP method according to Sternberger. We studied the presence of histiocytic markers lysozyme and alpha 1-antichymotrypsin, the content of albumin and of immunoglobulins and the question of immunophagocytosis and the presence of fibronectin. Various forms of activation of epithelioid cells as well as histiocytes and Langhans giant cells were found thereby. In the former, a phagocytosis could never be demonstrated, whereas this was true in histiocytes and giant cells. Fibronectin was not found in epithelioid cells. The findings suggest that epithelioid cells are a specific form of reaction of histiocytic elements. Thus they are a special reaction of MPS in a multiple causal genesis and a morphogenesis according to its own characteristics within a hypersensitivity reaction of a delayed type. Epithelioid cells modulate the immune response and in this way the tissue reaction.

Albumins↗
PubMed1992

Nonviable autologous bronchoalveolar lavage cell preparations induce intradermal epithelioid cell granulomas in sarcoidosis patients.

Intracutaneous injection of sarcoidosis patients with Kveim-Siltzbach antigen (KSAg), a particulate suspension of granulomatous sarcoidal spleen, induces an influx of T-helper lymphocytes and monocyte-macrophages followed by epithelioid cell granuloma formation. In the lung, similar granulomas form from an alveolitis of similar mononuclear cells, which may harbor a Kveim-like granulomagenic factor. To assess this possibility, preparations of nonviable autologous bronchoalveolar lavage cells (NABC) and KSAg were injected intracutaneously at different sites and biopsied at 4 to 5 wk. Of 22 sarcoidosis patients, nine (41%) developed typical granulomas at the NABC site, while all developed granulomas at the KSAg site. Responders to NABC had more recent onset of symptoms than nonresponders (3.2 versus 23.7 months, p less than 0.01), but did not have significantly higher percentages of lavage lymphocytes or more rosetting of lymphocytes about alveolar macrophages. None of 11 normal volunteers developed granulomas in response to NABC. Epithelioid cell granulomas at NABC and KSAg sites were similar by hematoxylin-eosin staining and by biotin-avidin-peroxidase immunohistochemical staining with monoclonal antibodies Leu-1, Leu-14, Leu-2a, Leu-3a, anti-interleukin-2 receptor, and polyclonal antibodies against lysozyme and alpha 1-anti-chymotrypsin. Symptomatic onset of sarcoidosis is associated with an autologous lavage cell factor that induces intradermal epithelioid cell granulomas that are immunophenotypically similar to Kveim-induced granulomas.

Adult↗
PubMed2002

Congenital giant melanocytic nevus with pigmented epithelioid cells: a variant of epithelioid blue nevus.

Epithelioid-cell blue nevus is an unusual cytologic variant of blue nevus that has been recently described mostly in patients with Carney complex, although the lesion may also appear in patients with no evidence of Carney complex. This variant of blue nevus is composed of melanin laden large polygonal epithelioid melanocytes situated within the dermis. The neoplastic cells show no maturation with progressive descent and, in contrast with the usual stromal changes in blue nevi, epithelioid-cell blue nevus exhibits no dermal fibrosis. This report describes a congenital giant melanocytic nevus with pigmented epithelioid cells located on the back of a 2-year-old male. The lesion was present at birth and the patient had no evidence of Carney complex. Histopathologically, the lesion consisted of a large and entirely intradermal melanocytic nevus composed of heavily pigmented epithelioid melanocytes involving the full-thickness of dermis, but extending also to the subcutaneous fat and underlying soft tissues. Immunohistochemically, epithelioid neoplastic melanocytes expressed immunoreactivity for S-100 protein, HMB-45, Melan-A, NK1C3, and microphthalmia transcription factor (MiTF) antibodies. MIB-1 cellular proliferation marker was expressed in the nuclei of only a few scattered epithelioid melanocytes. This report demonstrates that epithelioid-cell blue nevus is a distinctive histopathologic variant of blue nevus that may also appear as a giant congenital melanocytic nevus.

Biomarkers, Tumor↗
PubMed1983

Electrical properties of cultured epithelioid cells (MDCK).

This is a study of the intracellular electrical potential, membrane resistance, and capacity of MDCK cells (epithelioid of renal origin) cultured in monolayers on a collagen couch. These monolayers have a transepithelial resistance of 256 +/- 12 (22) ohm cm2 (mean +/- standard error, and number of observations), and the cells have 61.6 +/- 6.3 (92) M omega across their plasma membrane. The electrical capacity of the cells is 45.1 +/- 2.9 (63) pF and is much higher than expected for a cell of its size (diameter 14 micrometers, height 5 micrometers) and cannot be attributed to intercellular coupling, as no evidence of this type of connection was found in 20 pairs of neighboring cells. On the contrary, the high capacity is in keeping with previous studies using electron microscopy showing microvilli and a high degree of lateral infolding. The relationship between resistance and capacity was 1981 +/- 177 (61) omega . microF. The cells have an intracellular potential of -40.5 +/- 15 (120) mV. Yet the shape of the distribution curve suggests that the actual value may be somewhat higher (some -50 mV). The current/voltage curve of the distribution curve suggests that the actual value may be somewhat higher (some -50 mV). The current/voltage curve shows a marked asymmetry, and in some cells the voltage becomes time-dependent for large, depolarizing current pulses.

Animals↗
PubMed1994

[Origin and cytogenetic abnormalities of sarcoid epithelioid cells].

The sarcoid epithelioid cells are believed to be a variant of tissue macrophages, which derived from circulating monocytes in blood. Formation of monocytes and macrophages are controlled by hematopoietic growth factors, i.e; colony-stimulating factors in the bone marrow. In the presence of colony-stimulating factors and/or vitamin D3, blood monocytes can proliferate and differentiate into epithelioid cells and multinucleated giant cells. In view of the evidences that sarcoid granulomas produce colony-stimulating factors and active form of vitamin D3, these results suggest that active metabolites of vitamin D3 and colony-stimulating factors produced by sarcoid epithelioid cells, induces the differentiation and proliferation of circulating monocytes into macrophage-epithelioid cells, which in turn form sarcoid granulomas. Since sarcoidosis is a disorder of cell proliferation and differentiation, a question has been always kept in my mind whether the sarcoid granulomas are chronic inflammation per se or neoplastic in nature. Interestingly, cytogenetic studies revealed that most of the epithelioid cells were aneuploid; the chromosomal number ranged from the near-haploid to the near diploid number. In addition, The distribution of DNA content of the granuloma cells was fairly wide. Our observations raise a question whether the aneuploidy in sarcoid granulomas may be due to viral infection or exposure to carcinogens as in the case of neoplastic cells. It is also possible to speculate that the aneuploidy may be a mechanism of macrophage differentiation similar to immunoglobulin gene rearrangement in B lymphocytes. Further studies are required.(ABSTRACT TRUNCATED AT 250 WORDS)

Aneuploidy↗
PubMed1993

Epithelioid cell melanomas have greater DNA ploidy abnormalities than spindle cell melanomas: cytological evidence for a higher malignant potential of the former.

The cellular DNA ploidy of 30 cases of malignant melanoma was measured by 4',6-diamidino-2-phenylindole-DNA (DAPI-DNA) microfluorometry. DNA histograms and DNA index values were compared among melanomas of different cell morphology. Epithelioid cell melanomas often showed greater DNA aneuploidy than spindle cell melanomas in terms of histographic pattern. DNA index values of the former (mean +/- standard error, 1.84 +/- 0.31) were significantly higher than those of the latter (1.55 +/- 0.24; P < 0.05). The DNA index values of mixed-type melanomas were intermediate. These results indicate that the epithelioid cell melanomas have greater DNA ploidy abnormalities which are usually correlated with a greater malignant potential in pigmentary neoplasms. Thus our results confirm clinical evidence that melanoma patients with the epithelioid type of cells have a poorer prognosis than those with the spindle type of cells.

Adult↗