muramidase and Astrocytoma

A 2-year-old Sprague-Dawley rat with hindlimb paralysis was diagnosed with a cerebral malignant astrocytoma. The distinctive feature of this astrocytoma was the presence of scattered binucleated cells that contained hypereosinophilic, 1-2 micro m in diameter, cytoplasmic granules. The neoplastic astrocytes stained positively for vimentin (VIM), lysozyme, and phosphotungstic acid hematoxylin (PTAH). Within the binucleated cells, granules stained with PTAH and periodic acid-Schiff (PAS) before and after diastase digestion. Ultrastructurally, neoplastic astrocytes were characterized by cytoplasmic aggregates of electron-dense intermediate filaments consistent with VIM and desmin. The cytoplasm of binucleated cells contained numerous phagolysosomes enlarged by myelin figures and glycoprotein or glycolipid. Intermediate filaments were not present. This is the first description, in the rat, of a neoplasm with features resembling the human granular cell astrocytoma. Our findings suggest that an astrocytic origin should be considered for the binucleated cells in this neoplasm.

Topics: Animals; Astrocytoma; Brain Neoplasms; Granular Cell Tumor; Immunohistochemistry; Microscopy, Electron; Muramidase; Phosphotungstic Acid; Rats; Rats, Sprague-Dawley; Rodent Diseases; Telencephalon; Vimentin

Investigations were performed to become acquainted with the immunohistochemical features of foam cells localized perivascular and intratumoral in neoplasms of neuroectodermal origin. Antibodies against lysozyme (muramidase) (LO), alfa 1-antitrypsin (AT), protein S-100 and glial fibrillary acid protein (GFAP) were used. A weak or medium intense reaction result has been obtained in the cytoplasm of the foam cells if antibodies against LO, and alfa 1-antitrypsin and almost negative result if antibodies against protein S-100 and GFAP were used. Only very few cells which differ from the foam cells morphologically were very intense stained with primary antibodies against LO and alfa 1-antitrypsin. In accordance with the present views the LO and AT positive cells were recognized as macrophages. The application of macrophage markers did not allow us to ascribe unequivocally the foam cells macrophage-like or histiocyte-like properties. May be that the foam cells in tumors of perivascular and intratumoral localization present another phenotypic defined group of histiocytes, despite their morphological similarity to those cells derived from smooth muscle cells of arterial blood vessels observed in arteriosclerosis.

Topics: alpha 1-Antitrypsin; Astrocytoma; Brain Neoplasms; Ectoderm; Foam Cells; Glial Fibrillary Acidic Protein; Glioblastoma; Humans; Immunohistochemistry; Lymphocytes; Meningeal Neoplasms; Meningioma; Muramidase; S100 Proteins

Topics: Astrocytoma; Brain Neoplasms; Ependymoma; Glioma; Humans; Muramidase; Neoplasm Metastasis; Pituitary Neoplasms