Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.17 (lysozyme)
 21,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Interrelationships of immunologic and enzymatic markers of histiocytes have been studied in malignant neoplasms of histiocytic/monocytic origin and in differential diagnostically relevant, large cell non-Hodgkin's lymphomas. Cryostat sections required for demonstrating cell surface antigens by monoclonal antibodies are inadequate for studying cellular detail, enzymatic maturation by alpha-naphthyl acetate esterase (ANAE), and demonstrating the classical cytoplasmic markers of histiocytes like lysozyme, alpha-1-antitrypsin (AT), and alpha-1-antichymotrypsin (ACT). These markers have been compared in gently fixed and vacuum paraffin-embedded material. The reactivity for monoclonal anti-human monocyte 1 (Mo 1) has also been preserved by this method. Malignant histiocytosis (MH) is characterized by a heterogeneous cell population. The mature, ANAE-positive cells with macrophage morphology usually show a diffuse cytoplasmic positivity for AT and ACT. Lysozyme is moderately positive to negative in these cells, but it is more efficient than these markers in revealing smaller cells resembling monocytes by focal positivity in the cytoplasm. The expression of Factor XIIIa (F-XIIIa) is connected with the phagocytic activation of histiocytic cells. F-XIIIa positive cells usually form a minority of the neoplastic population in MH, but the large cytophagocytic marcophages are invariably positive. Reactive macrophages in large cell non-Hodgkin's lymphomas are characterized by a coexpression of ANAE, AT, ACT, lysozyme, F-XIIIa and Mo 1. Typical cases of true histiocytic lymphoma (THL) are made up of a homogeneous population showing the above mature, phagocytizing phenotype. In MH, Mo 1 and ANAE recognize different subpopulations. The reciprocal relation of these markers is an abnormal phenotypic feature. The results presented in this article prove the diagnostic value of ANAE and lysozyme in confirming the histiocytic differentiation of malignant cells. Monoclonal anti-human monocyte 1 is useful for identifying the immature component in MH. Factor XIIIa can be considered a functional marker of mature phagocytic histiocytes and an aid in the diagnosis of THL.
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PMID:Diagnostic significance of histiocyte-related markers in malignant histiocytosis and true histiocytic lymphoma. 290 5

A 66-year-old man was admitted for shortness of breath and showed fever, abdominal fullness and paraplegia. Monocytosis amounting to 25% and an elevation of serum LDH (4,281 mIu), were remarkable in the laboratory findings. He died of pulmonary insufficiency about a month after admission. On autopsy hepatomegaly (1950 g), splenomegaly (780 g), but no lymphadenopathy and small infarction in the thoracic spinal cord causing paraplegia was noted. Histopathologically, the invasion of the tumor cells into the liver, spleen, lymph nodes, bone marrow and other organs was observed. Malignant histiocytosis was diagnosed by histologic and immunohistochemical studies (lysozyme positive, S-100 protein negative).
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PMID:[A case of malignant histiocytosis with paraplegia]. 362 41

Midline malignant reticulosis (MMR), a disease included in the lethal midline granuloma, is histologically characterized by a mixture of lymphoid cells and atypical reticulum cells. Recent investigations of the nature of proliferating cells in MMR have suggested different conclusions, i.e., that the lesion is a true histiocytic, B- or T-cell. Two cases of MMR are presented, on which extensive laboratory studies were carried out. The results showed that the atypical reticulum cells were negative when stained immunohistochemically with monoclonal antibodies for T- or B-cells, diffusely stained by reactions for acid phosphatase and alpha-naphthyl acetate esterase, positively stained with human lysozyme and alpha-1-antitrypsin, and possess abundant cytoplasm containing primary lysosomes, polylysosomes and residual bodies. These findings indicate the true histiocytic nature of the proliferating cells in MMR.
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PMID:Immunohistochemical and ultrastructural studies on disseminated skin lesions of midline malignant reticulosis. 374 52

A second histiocytic proliferative disorder, which resembled malignant histiocytosis of man, was identified in 13 Bernese mountain dogs. Malignant histiocytosis was clearly distinct from systemic histiocytosis, which was reported earlier in this breed. Eleven cases involved male dogs. Ten dogs occurred in the same family line as the dogs afflicted with systemic histiocytosis. Clinical or radiological evidence of pulmonary involvement was present in nine dogs. Neurological disturbances were present in five dogs. Anemia was observed in five dogs and was associated with prominent erythrophagocytosis in two instances. The clinical course was rapidly progressive. Necropsy examinations revealed that infiltrates were especially frequent in the lungs and hilar lymph nodes. Other lymph nodes, liver, spleen, and central nervous system were also frequently involved. Evidence for primary pulmonary involvement was present in seven dogs. The original diagnosis in seven cases was large cell anaplastic carcinoma of the lung by light microscopy only. The infiltrates were composed of large, pleomorphic, phagocytic mononuclear cells and multinucleated giant cells which also manifested marked cytological atypia and numerous, frequently bizarre, mitotic figures. Ultrastructural studies and the immunohistochemical demonstration of lysozyme and alpha 1-antitrypsin in the tumor cells in the majority of cases were consistent with a macrophage origin.
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PMID:Malignant histiocytosis of Bernese mountain dogs. 394 51

Malignant histiocytosis (MH) is a true histiocytic disorder, whose identification is still based on too broad morphologic criteria. Using routine histology, cytochemical and immunohistochemical techniques on involved lymph nodes, 15 cases of MH have been investigated. Pleomorphism and cellular atypia, phagocytosis, lack of cohesiveness between proliferating cells, sinusoidal involvement, and plasmacytic infiltrate were the most common histologic features. MGG-stained imprints from 14 cases showed a composite tumor population mainly consisting of histiocyte-appearing cells, poorly differentiated atypical cells, and multinucleated giant cells. These cells, irrespective of cytologic features, revealed a diffuse, moderately to strongly positive reaction with acid phosphatase and nonspecific esterase. Naphthol-AS-D-chloroacetate esterase, Sudan black B, alkaline phosphatase, and beta-glucuronidase reactions were completely negative. Immunoperoxidase studies in 11 cases demonstrated that tumor cells stained positively for both kappa and lambda chains. These cells were also positive for albumin. Polytypic staining for IgG was observed in two cases, and a weak staining for lysozyme was found in two other nodes. Global results confirm the value of these studies for functional profile determination of MH proliferating cells. A combined approach using a variety of cytochemical and immunohistochemical techniques should be routinely considered in MH as useful additional studies for a more precise diagnostic definition of the disease.
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PMID:A cytochemical and immunohistochemical approach to malignant histiocytosis. 616 44

Malignant histiocytosis (MH) is a rare, usually fatal systemic disease considered to be a neoplasm of true histiocytes. Because MH may be difficult to differentiate from non-Hodgkin's lymphomas or carcinoma, we examined surgical and autopsy material from 10 patients with MH using the immunoperoxidase technique to determine if the presence of intracellular lysozyme is helpful in making this distinction. The cases of MH were divided into three groups based on the degree of cytologic atypia and the amount of phagocytic activity of the neoplastic cells: group I--minimal cytologic atypia and rare erythrophagocytosis; group II--minimal cytologic atypia with extensive erythrophagocytosis: group III--moderate to marked cytologic atypia and rare phagocytosis. Moderate to strong staining for lysozyme was observed in the neoplastic cells of group I, weak or absent staining in group II cells, and no staining in group III cells. These findings suggest the loss of detectable enzyme in poorly differentiated or dedifferentiated neoplastic histiocytes. Consideration must be given to these observations in evaluating the use of lysozyme as a possible serum or tissue aid to the diagnosis of MH.
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PMID:Relationship of lysozyme (muramidase) to histiocytic differentiation in malignant histocytosis: an immunohistochemical study. 698 34

Ten tumors of true histiocytic origin (Histiocytic Sarcoma) are presented. The tumor cells were identified as histiocytes by immunological, cytochemical and ultrastructural criteria (cytoplasmic lysozyme activity, presence of C3 and Fc gamma receptor, strong acid phosphatase and alpha-naphthyl acetate esterase activity, presence of lysosomes, absence of cell junctions and evidence of phagocytosis). The tumors identified in this way showed the following histological characteristics: diffuse proliferation of large tumor cells with ample cytoplasm, containing granular or occasionally diffuse diastase resistant PAS positive material, erythrophagocytosis, and haemosiderin pigment. The large or enormous nuclei were irregular, with occasional deep indentations, sharply defined nuclear membrane, coarse chromatin and conspicuous nucleoli. Despite the uniformity of these criteria differences in presence of alpha 1-antitrypsin, alpha 1-antichymotrypsin and 5 Nucleotidase activity and the number of lysosomes in the cytoplasm were found. The findings are suggestive of a spectrum of cytological in these Histiocytic Sarcomas. The clinical picture ranged from monolocalization in a lymphoid organ to that of a diffuse Malignant Histiocytosis. The relationship between good response to therapy and complete remission and the absence of alpha 1-antitrypsin and a high number of lysosomes is discussed.
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PMID:Malignant lymphoma of true histiocytic origin: histiocytic sarcoma. A morphological, ultrastructural, immunological, cytochemical and clinical study of 10 cases. 728 92

Malignant histiocytosis is a well-recognized canine tumour, occurring primarily in Bernese mountain dogs and characterized by disseminated histiocytic infiltration of multiple visceral organs. This report describes the light microscopical and ultrastructural features of a neoplasm composed of malignant histiocytes and confined to the brain. A poorly demarcated mass in the right parieto-occipital lobe of a miniature schnauzer was composed of loosely aggregated, pleomorphic cells with abundant eosinophilic cytoplasm, expanding the meninges. Many binucleated and multinucleated giant cells and mitotic figures were seen. Immunohistochemically, the tumour cells reacted intensely for lysozyme. Ultrastructurally, the neoplastic cells had features of histiocytic cells with abundant lysosomes. The findings in this case were strikingly similar to those of disseminated malignant histiocytosis described in other dog breeds.
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PMID:Primary malignant histiocytosis of the brain in a dog. 1037 96

Malignant histiocytosis was diagnosed in 4 cows. In all cases the tumor tissues were composed of cytologically atypical histiocytes with evidence of erythrophagocytosis. The tumor in case 1 appeared highly anaplastic with marked nuclear pleomorphism, and had areas of spindle cell differentiation, but had no relation to malignant fibrous histiocytoma. The neoplastic tissue in case 2, characterized by cohesive growth of tumor cells, was distinguishable from anaplastic carcinoma cells by cytokeratin immunostaining. There were many hemosiderin-laden neoplastic cells suggestive of high phagocytic activity in a lymph node of case 3. The neoplastic cells in case 4, frequently multinucleated, were less atypical than in the other cases. All cases expressed histiocyte-associated markers (lysozyme and HAM56), and were negative for cytokeratin, S100, and T- and B-cell lineage-specific markers (CD3 and CD79a). The most frequent HAM56 immunoreactivity was detected in case 4, and the giant, multinucleated forms, reminiscent of epithelioid cell differentiation. seemed not to indicate cytological pleomorphism as a result of neoplastic transformation.
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PMID:Malignant histiocytosis in cattle. 1119 37

Malignant histiocytosis (MH) was diagnosed in a 13-year-old neutered male Domestic Shorthair cat on the basis of light microscopic and immunohistochemical findings. Thoracic fluid analysis showed a modified transudate which contained a very few atypical discrete cells. Cytologic and histologic evaluation of mediastinal and splenic masses revealed a pleomorphic population of large, discrete, round cells 10 to 30 micrometers in diameter with marked cellular atypia. Nuclei were oval to reniform, often with prominent, bizarre nucleoli. Multinucleated cells and mitotic figures were commonly seen. Erythro- and leucocytophagia were noted. Immunohistochemistry indicated a scattered positive staining pattern with the histiocytic antigenic marker Mac387 and a minor population of cells showing positive reactivity for lysozyme. This report describes the characterization of MH in a cat and emphasizes that MH should be considered as a differential diagnosis in proliferative disorders of discrete-cells in this species.
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PMID:Malignant histiocytosis in a domestic cat: cytomorphologic and immunohistochemical features. 1265 95


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