Human immunodeficiency virus infection in microglia: correlation between cells infected in the brain and cells cultured from infectious brain tissue

In acquired immunodeficiency syndrome, the lesions of the central nervous system in association with the human immunodeficiency virus are thought to be related to an infection of microglia, although no studies are available in which cultured and physiological characteristics of microglia cells infected in vivo have been examined. In this report, we used brain tissue from a child dying of human immunodeficiency virus infection and show that microglia cells were the main cell population being infected. Moreover, isolated macrophage-like cells from fresh brain material revealed a close resemblance to peripheral blood macrophages in their content of surface and intracellular antigens. No virus particles or viral antigens were produced by these cells during the first week of cultivation. Productive infection was readily apparent, however, by day 30. This finding illustrates the slow nature of the virus life cycle in these cells and the minimal cytopathology that accompanied the infection.

AL amyloidosis mimicking a preferentially autonomic chronic Guillain-Barré syndrome

We report a case history of a patient whose diagnosis of AL amyloidosis remained elusive until postmortem examination. Exhaustive autonomic neuropathy mimicking a chronic Guillain-Barré syndrome dominated the clinical picture. The problems in establishing the definitive diagnosis of AL amyloidosis even in the face of strong clinical evidence are discussed.

Histiocytic tumor of Meckel's cave. An intracranial equivalent of juvenile xanthogranuloma of the skin

We present the case of a 7-year-old boy who had a solitary mass within Meckel's cave that recurred 6 weeks after the initial resection. The histological, immunohistochemical, electron-microscopical, and molecular genetical features established the lesion's histiocytic nature. Our findings showed that it was closely related to juvenile xanthogranuloma, a benign lesion that usually occurs in the skin but has not yet been histologically confirmed in the brain. The present tumor is different from other intracranial histiocytic and xanthogranulomatous lesions.

Animal experiments with a new dura graft (polytetrafluorethylene)--results

A comparative animal experiment study on rabbits was performed to test a synthetic dura (expanded polytetrafluorethylene = ePTFE = Gore-Tex Surgical Membrane). For the purpose of comparison with the ePTFE implanted in the left hemisphere, lyophilized natural dura (Lyodura) was used and removed from the subjects after two, eight and twelve weeks. There were no rejection reactions. The lyophilized dura showed pronounced environmental reaction, with cellular permeation and indications of revitalization. The ePTFE manifested only slight reaction and remained inert in an enclosing sheath of connective tissue. The biocompatibility and other properties, such as simple handling and resteriliziability, of ePTFE can thus be assessed as positive.

Myelinoclastic diffuse sclerosis (Schilder's disease): cliniconeuroradiologic correlations

We report a 17-year-old boy with myelinoclastic diffuse sclerosis (Schilder's disease) presenting with left leg paresis, visual loss, and behavioral changes. CT and MRI showed two large lesions in the subcortical white matter of the occipital and parietal lobes of both hemispheres and increased intracranial pressure. Histology disclosed large areas of demyelination and perivascular infiltrates. The patient improved with coincident oral prednisolone treatment.

Simultaneous bilateral diffuse melanocytic uveal hyperplasia

A 52-year-old woman noted loss of vision in August 1984. Clinical examination disclosed iris cysts and ciliary body cysts, macular edema, and uveal nevi. Cataract extraction and pressure-lowering operations were required in both eyes because of a tumor-induced angle-closure glaucoma. Vision, however, progressively decreased to light perception in each eye. Both eyes were finally enucleated because a malignant melanoma could not be ruled out, though iris tissue obtained in 1985 suggested a nevuslike process. Histologic study indicated a bilateral uveal hyperplasia. Results of light and electron microscopy, immunologic studies, and suspension cell culture suggested that the uveal hyperplasia was more likely a melanoma of low malignancy than a nevuslike process. We could not detect an extraocular primary tumor and assumed that this condition constituted an oncogenic syndrome.

Immunohistochemical demonstration of glycogen phosphorylase in rat brain slices

Paraffin-embedded sections from paraformaldehyde-fixed rat brain were stained immunocytochemically for glycogen phosphorylase brain isozyme BB, using a monoclonal mouse antibody and the biotin-strept-avidin method, with either horseradish peroxidase or beta-galactosidase as marker enzymes. Two cell types showed strong glycogen phosphorylase-immunoreactivity: Astrocytes and ependymal cells. Most intensive staining was observed in the cerebellar cortex, the neocortex and the hippocampus. Astrocytes in the cerebellar white matter stained positively. The choroid plexus cells stained poorly or not at all. Neurons throughout the brain were negative, as well as oligodendrocytes and bundles of myelinated nerve fibers. These data are consistent with the immunocytochemical localization of glycogen phosphorylase in astroglia-rich primary cultures derived from rat brain.

Localization of basic fibroblast growth factor, a mitogen and angiogenic factor, in human brain tumors

Fibroblast growth factor (FGF) is a potent angiogenic factor and a mitogen for a variety of mesoderm- and neuroectoderm-derived cell types (e.g., fibroblasts, endothelial cells, astrocytes, oligodendrocytes). After application of a monospecific polyclonal antiserum, we localized basic FGF on frozen sections of 73 human brain tumors using immunohistochemistry. FGF was present in a variable number of tumor cells (16/16 astrocytomas, 5/5 ependymomas, 0/3 benign and 4/7 anaplastic oligodendrogliomas, 11/12 glioblastomas, 11/11 meningiomas, 6/6 neurilemmomas, 0/3 pituitary adenomas, 2/2 choroid plexus papillomas, 0/1 neurocytoma, 2/2 benign fibrous histiocytomas, 2/5 metastatic carcinomas). FGF was detected in vascular cells of 59 tumors and in fibroblasts of connective tissue stroma from all papillomas and metastases. These results tend to indicate FGF involvement in the malignant progression of gliomas due to an autocrine or paracrine action. Histopathological aspects of malignant gliomas (e.g., pseudopalisading or pathological vessels) could be related to FGF activity.

Monoclonal antibody analysis of major histocompatibility complex expression in human meningiomas

Using monoclonal antibodies (MAB) in combination with the alkaline phosphatase anti-alkaline phosphatase technique, 20 meningiomas were examined for the expression of major histocompatibility complex (MHC) antigens. Most of the tumor cells were labeled with the MAB for class I MHC antigens. In addition, class I reactivity was seen in the tumor blood vessels, presumably reflecting labeling of the endothelial cells. Tumor cells and endothelium were not labeled with the MAB for class II MHC antigen HLA-DR. Occasionally a staining of periendothelial cells was detected. The presence of MHC antigens supports the assumption that endothelial cells play a role in antigen presentation, perhaps relevant to the initiation of an immune response, and that meningioma cells can be a target of T cell-mediated immune reactions.

Ragged-red fibres detected in paraffin sections by a monoclonal antibody to inner mitochondrial membrane

An immunohistochemical method is reported using the M-II68 monoclonal antibody, which detects mitochondrial accumulations ("ragged-red fibres") in routinely processed (formalin-fixed, paraffin-embedded) muscle tissue. Ten cases with electron-microscopically and histochemically proven mitochondrial myopathy featured 4% to 24% ragged-red fibres. In a series of 50 muscle biopsies without mitochondrial myopathy, scattered ragged-red fibres (less than 0.1%) were present in a few normal and pathological muscles. The immunohistochemical method is specific for mitochondria, does not require frozen tissue and permits rapid examination of large areas.

Immunohistological investigation of mononuclear cell infiltrates in meningiomas

Immunohistochemical analysis of inflammatory cell density and infiltrate subpopulations in 42 meningiomas was performed. Evaluation of infiltrating cell density was carried out by cell counting. Meningothelial and fibroblastic meningiomas contained an average of 3% mononuclear cells; the few lymphocytes were localized in the perivascular spaces. In subtypes with cellular atypies and recurrent tumors, the inflammatory cells increased up to 9%. We found small mononuclear cell clusters in the tumor parenchyma in addition to the perivascular infiltrates. Marked degrees of infiltration were found in anaplastic meningiomas (average 13.5% of total cells). The lymphocytic infiltrates were localized in multilayered perivascular cuffings and intraparenchymal cell clusters. The composition of the infiltrates, i.e., predominantly a mixed staining of cytotoxic/suppressor and helper cell phenotypes, did not vary in the different subtypes. We conclude: (1) that inflammatory infiltration is more frequent and denser in malignant than in benign meningiomas; and (2) that the tumor defense mechanisms in meningiomas are mediated particularly by T cell mediated immunity.

Sphingolipid activator protein deficiency in a 16-week-old atypical Gaucher disease patient and his fetal sibling: biochemical signs of combined sphingolipidoses

We describe a patient who presented shortly after birth with hyperkinetic behaviour, myoclonia, respiratory insufficiency and hepatosplenomegaly. Gaucher-like storage cells were found in bone marrow. A liver biopsy showed massive lysosomal storage morphologically different to that in known lipid storage disorders. Biochemically, the patient had partial deficiencies of beta-galactocerebrosidase, beta-glucocerebrosidase and ceramidase in skin fibroblast extracts, but the sphingomyelinase activity was normal. Glucosyl ceramide and ceramide were elevated in liver tissue. Loading of cultured fibroblasts with radioactive sphingolipid precursors indicated a profound defect in ceramide catabolism. Immunological studies in fibroblasts showed a total absence of cross-reacting material to sphingolipid activator protein 2 (SAP-2). The patient died at 16 weeks of age. The fetus from his mother's next pregnancy was similarly affected. The possibility that the disorder results from a primary defect at the level of SAP-2 is discussed. We have named this unique disorder SAP deficiency.

Mitochondrial encephalomyopathy with pilovacuolar inclusion or phenocopy with mitochondrial artefact?

The case of a 33-year-old man with clinical features of mitochondrial encephalomyopathy is presented. He suffered from recurrent cerebral infarctions, cerebellar ataxia, deafness, retinopathy, weakness, and cardiac and renal disorders. Biochemical and light microscope investigations of skeletal muscle did not show any mitochondrial abnormality. Electron microscopy revealed the presence of a hitherto unreported peculiar "pilovacuolar" inclusion in numerous mitochondria, composed of an electron dense pile or rod within a vacuole, while globular or crystalline inclusions were absent.

Meningio-angiomatosis

A case is described of a boy five years old who suffered from left-sided muscular weakness since the first months of life and from absences since the second year of life. He died of valproate-induced hepatic insufficiency. Autopsy of the brain revealed meningio-angiomatosis, a rare but rather benign disorder usually characterized by narrow meningothelial proliferations abutting upon cortical plaques and exhibiting proliferations of small vessels with perivascular cuffs of fibroblast-like cells. The peculiarities were that the case lacked any leptomeningeal calcification - in line with the patient's age being the lowest so far reported for pathologically verified meningio-angiomatosis - and also exhibited intracortical clusters of mesenchymal cells that did not form vessels ("free fibroblasts"). Immunohistochemically perivascular cells were negative for S100, GFAP, desmin and factor-8-related antigen and were embedded in interstitial collagen of types III and VI as well as procollagen I, while "free fibroblasts" were surrounded by deposits of basement membrane collagen type IV. The results are consistent with a meningothelial origin of perivascular cells and "free fibroblasts".

A case of combined Farber and Sandhoff disease

We describe a patient with the biochemically established combination of Farber and Sandhoff disease. A 6-month-old girl of consanguineous Turkish parents presented with hoarseness, stridor, scattered skin nodules, painful swelling of hand joints and ankles, and cherry-red macular spots. Until the age of 2 years her motor and physical condition deteriorated distinctly, however her mental state remained unchanged. A biopsied skin nodule disclosed lysosomal inclusions within storage cells that were typical of Farber disease (curved tubular structures). However, other inclusions (e.g. zebra bodies) were also found. Biochemical findings included ceramide accumulation in skin nodules and cultured fibroblasts, impaired ceramide degradation on loading of cultured fibroblasts with radioactive sphingomyelin, profoundly decreased ceramidase activity in fibroblasts as well as total beta-hexosaminidase activity in fibroblasts and serum, absent hexosaminidase A and B bands on cellogel zymograms, increased urinary oligosaccharide excretion of the Sandhoff disease type, and a partial reduction of ceramidase and total beta-hexosaminidase activities in fibroblasts from her father. A diagnosis of combined Farber and Sandhoff disease was made. The effect of both enzyme deficiencies on the clinical manifestations in this patient and the genetic basis of this combination require further studies.

Histogenesis of stromal cells in cerebellar hemangioblastomas. An immunohistochemical study

Fifteen cerebellar hemangioblastomas were examined by immunohistochemistry for expression of neuron-specific enolase (NSE) and various neuropeptides using the avidin-biotin-complex peroxidase reaction with the following antibodies: NSE, synaptophysin, serotonin, substance P, vasoactive intestinal peptide (VIP), neuropeptide YY, neurotensin, and leu-enkephalin. In all tumor biopsies most of the stromal cells were positive for NSE. About 30% of the stromal cells showed a weak cytoplasmic synaptophysin positivity. Approximately 25% of the stromal cells were labeled with antibodies against substance P and neuropeptide YY. The partly strong reactivity was localized preferentially in perinuclear regions. These positive cells were mainly distributed in small cell clusters but were also scattered in the tumor parenchyma. In all tumor biopsies scattered cells exhibited strong perinuclear enkephalin positivity, corresponding probably to mast cells, whereas stromal cells were entirely negative. For serotonin, VIP, and neurotensin no specific reaction was seen. On the basis of these findings it is proposed that hemangioblastomas have a neuroendocrine component.

Vimentin and glial fibrillary acidic protein are codistributed in the same intermediate filament system of malignant glioma cells in vivo. A double-labeling immunoelectron-microscopical study

Normal, reactive, and neoplastic astrocytes express two types of intermediate filament (IF) proteins, namely glial fibrillary acidic protein (GFAP) and vimentin. Their submicroscopical distribution in vivo is so far unknown. We therefore investigated four malignant gliomas by electron microscopy, applying postembedding double immunogold labeling. The IF proteins were randomly scattered over the same filament bundles, as in previous experiments on glioma cultures. No clustering or preferential intracytoplasmic location of either IF protein was visible. The demonstration of IF proteins within nuclei gives some support to the suggested intranuclear functions of IF proteins.

Mitochondrial myopathies with necrotizing encephalopathy of the Leigh type

Two patients with mitochondrial encephalomyopathy (MEP) serve to emphasize the variability of this group of diseases. Cerebral insults, mitochondrial cardiopathy, relapsing ileus, cerebral angioma, ataxia, and myoclonic seizures characterized the first case of an adult man with similar diseases in his family, interpreted as transitional form between mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) and myoclonus epilepsy associated with ragged red fibers (MERRF). The second patient, a floppy infant with cardiomyopathy and myoclonism, statomotoric and mental retardation showed combined defects in mitochondrial respiratory chain at NADH-CoQ reductase and cytochrome c oxidase and a deficiency of carnitine. In both patients neuropathologically criteria of Leigh's syndrome could be demonstrated in the cerebral cortex, in case 2 also clinically. The classificatory problems of the relationships between KSS, MELAS, MERRF, Leigh's as well as Alpers' syndromes are discussed.

Adult-onset rod disease with abundant intranuclear rods

The third case of adult-onset rod disease (nemaline myopathy) with abundant myofibrillar as well as intranuclear rods is described. The 61-year-old woman suffered from progressive weakness of proximal extremities and of the neck, mimicking polymyositis. Muscle biopsy revealed a striking myopathic pattern, with intranuclear rods occurring in 31% of the fibres. On light and electron microscopy and by immunohistochemical study, the rods differed from myofibrillar rods. The absence of alpha-actinin in intranuclear rods suggests an enhanced readiness of actin filaments to bind to diverse proteins, instead of overproduction of alpha-actinin as the pathogenetic basis of the rod formation.

[Mitochondrial encephalomyopathy: clinical aspects, CT morphology and neuropathology]

Basing on the example of two cases, the clinical and morphological variability of mitochondrial encephalomyopathies is demonstrated. Both patients were of short build, and the clinical signs and symptoms were dementia, ataxia, epilepsy and hardness of hearing, whereas signs of myopathy were very mild or absent. Computed tomography showed infratentorial pronounced atrophy of the brain and basal ganglia calcifications, in one case additionally ischemic infarctions, as can be seen in "mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes syndrome" (MELAS). A CT follow-up over 8 years with a progression of the abnormalities parallel to the progressive clinical course is demonstrated. Besides typical "ragged red fibres-myopathy" different abnormalities of mitochondria were seen by the electron microscope. One of the patients died; he had exceptional pathological-anatomical findings with mitochondrial cardiomyopathy, angioma and necrotising encephalopathy of Leigh's type. The two case reports show that in patients with such multisystemic neurological signs and CT-findings mitochondrial encephalomyopathy should be considered and a muscle biopsy should be performed.

Inflammatory infiltrates and natural killer cell presence in human brain tumors

Immunohistochemical analysis of subpopulations of inflammatory cells in 81 primary and secondary human brain tumors was done. Natural killer (NK) cells, representing non-major histocompatibility complex-restricted, spontaneous cytotoxicity and monocytic cells are virtually absent in infiltrates of gliomas and account only for a minor percentage of inflammatory cells in brain metastases of carcinoma and in craniopharyngeomas. Infiltrates in gliomas consist almost exclusively of T-cells of the suppressor/cytotoxic type whereas infiltrates in carcinoma metastases and craniopharyngeomas contain considerable numbers of T-helper/inducer cells and B-cells. From this the authors conclude (1) that NK cells do not play a major role in tumor rejection, and (2) that the kind of inflammatory reaction does not depend upon the tumor site but more likely on the tumor type. No correlation between tumor differentiation and infiltrate composition is evident.

Immunohistochemical investigation of collagen subtypes in human glioblastomas

The immunohistochemical distribution of a spectrum of collagens and procollagens was studied in 16 glioblastomas. Anti-collagen IV antibodies frequently outlined thickened or disrupted basement membranes (BM) of tumour vessels. Glial BM were frequently penetrated by tumour cells; endothelial BM were not. Some proliferating vessels did not stain for extracellular collagen IV but were rimmed by collagen IV-positive cells, some of which expressed GFAP. Procollagen I was restricted to proliferating leptomeninges and pathological tumour vessels. Collagen III and procollagen III were codistributed in intratumoural and extratumoural interstitial connective tissue. Collagen VI was most pronounced in the adventitia of normal vessels and in spindle-cell proliferations of pathological vessels but not in the endothelial cell proliferations. On the basis of our findings, we conclude that glial cells play a major role in BM formation around tumour vessels, that procollagen I may serve as a marker for proliferation of interstitial connective tissue, and that the origin of spindle-cell proliferation is adventitial, rather than endothelial.

Altered expression of collagen type VI in brain vessels of patients with chronic hypertension. A comparison with the distribution of collagen IV and procollagen III

The vascular extracellular matrix (ECM) plays an important role in the histopathology of cerebral microcirculation, but its characterization is still incomplete. For that reason we investigated paraffin-embedded and cryostat sections of intracerebral and meningeal vessels from eight normotensive and six hypertensive humans using monospecific affinity-purified polyclonal antibodies against human/monkey amino-terminal procollagen I + III peptide (P I P, P III P), collagen IV (7-S and NC1 domains), VI, and laminin (P 1 fragment) by applying peroxidase-antiperoxidase- and alkaline phosphatase-antialkaline phosphatase techniques. In normotensives, laminin and collagen IV were codistributed in the basal lamina of meningeal and intraparenchymal vessels. Collagen VI was only present in the adventitia of meningeal vessels and larger intraparenchymal arteries and veins, whereas it was absent from cortical vessels including capillaries. Intensive staining for collagen VI was observed in the choroid plexus, the superficial glia and sheath of cranial nerves. In hypertensives, the basement membrane constituents laminin and collagen IV appeared ubiquitously increased. Here, collagen VI was also deposited in the broadened vascular intima and media of larger arteries and in cortical vessels. In both groups collagen VI and P III P appeared to be codistributed. Our results indicate that significant qualitative change sin ECM of cerebral blood vessels are taking place during the development of hypertension, such as (1) an atypical deposition or an increase of collagen VI which by interconnecting collagen fibrils (I and III) might exert a stabilizing (sclerosing) function in the ECM, and (2) a thickening of vascular basement membranes caused by an accumulation of its major components laminin and collagen IV.

Proliferative potential of meningiomas determined with the monoclonal antibody Ki-67

In 30 meningiomas we investigated the proliferation rate of various subtypes with the monoclonal antibody Ki-67. Frozen sections were incubated with Ki-67 antibody using a modified Alkaline Phosphatase anti-Alkaline Phosphatase (APAAP)-technique and evaluation of proliferation rate was done by cell counting. Meningiomas of the meningiotheliomatous, fibrous and angioblastic subtype without atypical histological findings contained 1% or less proliferating cells. In recurrent tumors, in transitional and in anaplastic meningiomas there is a marked increase of proliferating cells up to 20%. The distribution of marked cells varies in recurrent tumors and anaplastic meningiomas, and a focal proliferation of tumor cells was seen in meningiomas from transitional type. Immunohistological labelling of proliferating cells in meningiomas may allow a more precise prediction of the proliferation potential of each meningioma.

Normomorphic sialidosis in two female adults with severe neurologic disease and without sialyl oligosacchariduria

Two female patients of German origin, aged 38 and 21 years, with myoclonus epilepsy and cerebellar ataxia, but without dysmorphic signs and dementia, were found to excrete normal amounts of sialyl oligosaccharides in their urine. The younger patient showed cherry red spots in her ocular fundi. The older patient had a brother with an autopsy-proven neuronal storage disease compatible with sialidosis, and in her rectal biopsy lamellar inclusion bodies were detected. Enzyme assays in cultured fibroblasts of both patients revealed a profound but incomplete deficiency of oligosaccharide sialidase activity and normal beta-galactosidase activity. Adult sialidosis was diagnosed in both patients. In their fibroblasts, moderate elevations of bound sialic acid could also be measured. The small residual sialidase activity, which in the older patient had a normal KM value, is considered responsible for the late onset and slow clinical course of the disease. It is concluded that in adult sialidosis the extraneural storage process can be difficult to demonstrate in terms of metabolite accumulation or excretion during the course of intraneuronal storage.