Philip E. Duffy

Identification of glial fibrillary acidic protein by the immunoperoxidase method in human brain tumors.

The immunocytochemical localization of glial fibrillary acidic protein within glioma cell bodies and their processes by the immunoperoxidase method is demonstrated to be of diagnostic value. This method has advantages over “special” stains because it is not so dependent upon color alone, and because it identifies a specific protein in the cells. The immunoperoxidase method using antiserum to glial fibrillary acidic protein is shown to be useful for the differentiation of mixed glial and mesenchymal tumors, and for the diagnosis of tumors in which a glial or mesenchymal cell origin is in doubt.

Glial fibrillary acidic protein in ependymomas and other brain tumors: Distribution, diagnostic criteria, and relation to formation of processes☆

Glial fibrillary acidic protein (GFAP) was studied in ependymomas by the three-step immunoperoxidase method and compared to results in astrocytomas and normal tissues. An order of reactivity for GFAP is presented. Diagnostic criteria, based on GFAP content, are proposed. In ependymomas GFAP-positive cells give rise to only some of the tumor cells, usually those forming tubules and perivascular arrangements. It is hypothesized that the same GFAP-positive cells may form tubules at their luminal poles and may produce perivascular arrangements at their other poles. The aberrant regulation associated with neoplastic transformation in glia is often, but not always, reflected in increased GFAP content. In both astrocytes and ependymal cells GFAP may have a similar function since in both cells the increase in GFAP appears to be related to the development of fibrillary processes.

Granular Cell Tumors of the Central Nervous System

This paper describes two cases of granular cell tumor, the first such tumors believed to have arisen in the central nervous system with the exception of those in the neurohypophysis. The tumor in one case arose in the cervical spinal leptomeninges and in the other was located in a cerebral hemisphere. The light and electron microscopic characteristics were indistinguishable from granular cell tumors (myoblastomas) reported in other body sites. Ultrastructurally two cell types could be distinguished. The predominant form (Type II) was characterized by abundant cytoplasm filled with dense bodies, multivesicular bodies and vacuoles. A second smaller cell (Type I) contained few of the above organelles. It is considered likely that these cell types are evolutionary stages of a single kind of a cell in which Type I is transformed into Type II. Various cells, including Schwann cells, have been proposed as giving rise to granular cell tumors. The occurrence of these neoplasms in the central nervous system lessens the likelihood of a Schwannian source in all instances. An origin from Schwann cells of perivascular nerves cannot be excluded. The possibility remains that neoplasms designated as granular cell tumors may have more than one cell of origin.

The relationship of glial fibrillary acidic protein to the shape, motility, and differentiation of human astrocytoma cells.

Abstract Glial fibrillary acidic protein (GFAP), a protein largely limited to astrocytes, was studied in relation to the shape, motility, and differentiation and malignancy of astrocytoma cells in tissue culture by use of time-lapse photography and the immunoperoxidase method. A relationship was observed between the shape of astrocytes and the distribution of GFAP. Spindle-shaped cells showed abundant GFAP in the cell body and processes. In round or polyhedral cells without well developed processes the GFAP was largely perinuclear. As processes developed, GFAP extended out from the nucleus iri dense parallel arrays that radiated into the developing processes. Fully differentiated cells with stellate shape had abundant GFAP throughout. A relationship was also observed between the motility of astrocytes and GFAP. Stellate-shaped cells, showing paucity of locomotion and relatively rigid postures of processes, contained an abundance of GFAP which tended to form dense parallel arrays extending into the processes during their development. Spindle-shaped cells with extending and retracting processes and active migration also contained an abundance of GFAP but not organized into parallel arrays. Bulbous dilatations at the tips of processes (growth cones) contained abundant GFAP. There was also abundant GFAP in the intermittent dilatations along the processes of stellate cells. In contrast to these observations, a retraction of processes, a high degree of plasticity (undulating motion) and multidirectional locomotion were often associated with a paucity of GFAP in less differentiated cells. We hypothesize that GFAP filaments may be inhibitory to great plasticity of motion but not to extension-retraction movements. During mitosis GFAP was sparse at the spindle and in intercellular bridges. Colcemid caused GFAP to disappear from processes and peripheral parts of the cell and to become concentrated near the nucleus. In cultures derived from malignant tumors, undifferentiated and large multinucleated cells usually showed sparsity of GFAP, but occasional well differentiated stellate or spindle-shaped cells containing abundant GFAP were seen. Conversely, although cultures derived from benign tumors may have scattered less well differentiated cells, the differentiated cells with well developed processes were most densely stained and account for the high concentration of GFAP in tissue from these tumors.

Hallervorden-Spatz disease and infantile neuroaxonal dystrophy: Ultrastructural observations, anatomical pathology and nosology

Abstract The gross and light-microscopic findings at autopsy of 2 new cases of Hallervorden-Spatz disease (HSD) of early onset and/or infantile neuroaxonal dystrophy (IND) are presented. Electron-microscopic detail of mineral pigment deposits and dystrophic axons (“spheroids”) proved to be indistinguishable in the 2 cases. The presence of numerous Lewy bodies in the substantia nigra of 1 of the cases was an unusual finding. In the same case, the ultrastructure of cytoplasmic inclusions in nerve cells of the cerebral cortex resembled the Lewy body. An analysis of the striking similarities and differences between these 2 cases and a review of previous reports lead to the conclusion that present knowledge does not permit a clear distinction between HSD of early onset and IND.

Glial fibrillary acidic protein in giant cell tumors of brain and other gliomas

SummaryThe giant cell tumor of brain (glioblastoma/sarcoma) has been considered a glioma by some and a sarcoma by others. This study shows that glial fibrillary acidic protein (GFAP), a specific “marker” for astrocytes, is present in the tumor cells, thus indicating that the cell of origin is the astrocyte and that the tumor should be called a giant cell glioblastoma. GFAP is present in the smaller cells of this tumor and in larger mononucleated cells, but little if any is detectable in multinucleated giant cells.In a different kind of tumor, the giant cell astrocytoma assonciated with tuberosclerosis, GFAP is restricted in most cells to a narrow peripheral zone.Immunocytochemical localization of GFAP is superior to “special stains” to differentiate giant cell glioblastomas from true sarcomas and giant cell bone tumors, since the latter are both negative for GFAP.Comparison of GFAP in all tumors of astrocyte origin shows that the cells that appear to contain the most GFAP include low grade well differentiated stellate cells, elongated “piloid” cells, and gemistocytic astrocytoma cells. Highly malignant undifferentiated cells, with less well developed processes, are less densely positive.Although there is in general an inverse relationship between GFAP content and degree of tumor malignancy, a more complex relationship exists with respect to individual cells; more GFAP is present in well differentiated cells with well-developed processes and filaments than in undifferentiated cells and large multinucleated cells. It is suggested that the pleomorphism of more malignant cells may relate to their relatively low GFAP content and perhaps to the disassembly of their glial filaments.

Immunocytochemistry of Pineal Astrocytes: Species Differences and Functional Implications

Immunohistochemical demonstration of glial fibrillary acidic protein (GFAP) was performed in human, sheep, rat and guinea pig pineal bodies to determine if there were species differences. Specialized “basket-like” arrangements of many GFAP-positive astrocytic processes were shown around sheep pinealocytes. Human pineals contained scattered astrocytic cell bodies and a moderate number of GFAP-positive astrocytic processes which, as in sheep, also surrounded pinealocytes, but without the dense basket-like arrangements. In both species GFAP-positive fibers were concentrated at the periphery of pseudolobules and around blood vessels. Rat and guinea pig pineals contained only rare astrocytic cell bodies and few GFAP-positive fibers throughout the glands, but had a concentration of parallel GFAP-positive fibers at the stalk. GFAP-positive fibers in human and sheep pineals may be derived from both intra- and extraglandular sites, whereas in rodents only rare processes appear to be derived from within the gland. Astrocytes may play a role in modulation of pineal indoleamines and norepinephrine, and the species differences observed suggest that this effect may be important in sheep and human pineals but not in rodents.

Murine Influenza Virus Encephalomyelitis

The development and maturation of neurotropic WS-N strain of influenza virus in encephalitic mice was shown to occur preferentially along the “free” surface of ependymal and choroid plexus cells where it developed from the cell membrane. Virus maturation and “budding” was generally absent along the other surfaces of the same cells where they were apposed to other cells. This may suggest an inhibitory effect of adjacent cell membranes. Electron microscopic observations of ependymal surfaces may be of importance in demonstrating some viruses in human and animal tissues. Most of the virions were rounded in shape with surface spikes but a considerable number of filamentous forms were seen developing at the tips of villi. Filamentous forms had previously been described in tissue culture but not in animal encephalitic tissues. Intracellular virus within vacuoles was seen en masse and a few virus-like structures appeared to form from endoplasmic reticulum. Intracytoplasmic inclusions were demonstrated. The virus appeared ultrastructurally at a time preceding and overlapping the time at which virus replication reaches its maximum. The electron microscopic results were also considered in relation to immunofluorescence evidence in a companion paper, that virus antigen is present in deeper cells even though few mature virions appear in those sites. The combined data suggests that virus initially has a predilection for ependymal cells where mature virions develop at the surface of the cells. Later there is extension of virus antigen to deeper cells with a presumed transfer from cell to cell without the same degree of maturation of virions at cell surfaces.

Ornithine decarboxylase activity and polyamines in relation to aging of human fibroblasts.

Summary A reduction of ornithine decarboxylase (ODC) activity is associated with the decreased growth rate in early senescence of human embryonic lung fibroblasts. Inhibition of ODC activity with α -methyl ornithine in younger cells reduces cell proliferation; inhibition of putrescine deamination with aminoguanidine increases intracellular putrescine concentration and stimulates cell proliferation. The data suggests that the decreased cell proliferation which occurs in senescence may, at least in part, be dependent upon the reduced ODC activity.

Electron microscopic cytochemistry and microgasometric analysis of cholinesterase in the nervous system.

Publisher Summary Techniques from different disciplines have been combined in the present investigation to provide more meaningful information. Electron microscopic-Cytochemistry and microgasometric analysis have been used to study acetyl cholinesterase in the sympathetic and dorsal root ganglia of the frog, using tissue blocks or isolated cells. In addition, some observations on the development of cholinesterase in the nervous system of the embryonic rabbit and human are presented. Cholinesterase activity of isolated sympathetic and dorsal root neurons has been studied by use of the Cartesian diver, which permits a more sensitive method for quantitative determination of the activity of the enzyme. It is shown that the neural plasma lemma is the ultimate permeability barrier to the substrates acetylcholine and acetylthiocholine. The review also mentions about the materials and methods used in these investigation studies. Cervical sympathetic ganglia and lumbar dorsal root ganglia of the frog were used for cytochemical studies. For developmental studies embryonic tissue of rabbits from 9 to 18 days gestation and of human fetuses from 2 to 3 months gestation were employed. From the microgasometric analysis and cytochemistry of isolated neurons studies, the chapter puts forward a proved theory that the intact neural plasma lemma, and possibly, the satellite sheath formed a permeability barrier to the substrate. The enzyme, Acetyl cholinesterase was demonstrated in two principle areas depending on whether the tissue was fixed or unfixed prior to incubation.