Heinz A. Gerber

Tuber and subependymal giant cell astrocytoma associated with tuberous sclerosis: an immunohistochemical, ultrastructural, and immunoelectron microscopic study

The cellular nature of the giant eosinophilic cells of tuber and of the cells comprising subependymal giant cell astrocytoma (SEGA) in tuberous sclerosis (TS) remains unclear. To assess the characteristics of these lesions, 13 tubers and 6 SEGA were immunohistochemically studied with glial and neuron-associated antigens. In addition to conventional ultrastructure, 6 tubers and 8 SEGA were fibrillary acidic protein (GFAP) and somatostatin. Eosinophilic giant cells of tubers were positive for vimentin (100%), GFAP (77%) and S-100 protein (92%); such cells were also found to a various extent to be reactive for neuron-associated antigens, including neurofilament (NF) proteins (38%) or class III β-tubulin (77%). SEGA also showed variable immunoreactivity for GFAP (50%) or for S-100 protein (100%); NF epitopes, class III β-tubulin, and calbindin 28-kD were expressed in 2 (33%), 5 (83%) and 4 (67%) cases, respectively. Cytoplasmic staining for somatostatin (50%), met-enkephalin (50%), 6-hydroxytryptamine (33%), β-endorphin (33%) and neuropeptide Y (17%) was noted in SEGA, but not in tubers. Ultrastructurally, the giant cells of tubers and the cells of SEGA contained numerous intermediate filaments, frequent lysosomes and occasional rectangular or rhomboid membrane-bound crystalloids exhibiting lamellar periodicity and structural transition to lysosomes. Some SEGA cells showed features suggestive of neuronal differentiation, including stacks of rough endoplasmic reticulum, occasional microtubules and a few dense-core granules. Furthermore, in one case of tuber, a process of a single large cell was seen to be engaged in synapse formation. Intermediate filaments within a few cells of both lesions were decorated by gold particle-labeled GFAP antiserum. Within the tumor cells of SEGA, irregular, non-membrane-bound, electron-lucent areas often contained somatostatin-immunoreactive particles, whereas the latter could not be detected in tuber. The present study provides further evidence of divergent glioneuronal differentiation, both in the giant cells of tubers and the cells of SEGA. The findings of similar cells at different sites, including the subependymal zone, white matter (“heterotopias”), and cortex indirectly supports the idea that these lesions of TS result from a migration abnormality.

Olfactory neuroblastoma. An immunohistochemical, ultrastructural, and flow cytometric study.

Background. Olfactory neuroblastoma is an uncommon neuroectodermal tumor of the upper nasal cavity, microscopic features of which are not always homogeneous. No morphologic features have been found to correlate reliably with prognosis. Methods. Twenty-six olfactory neuroblastomas occurring in 14 females and 12 males, ages 18–78 years, were studied by immunohistochemistry, electron microscopy, and DNA flow cytometry. Survival rates were statistically analyzed relative to several variables. Results. Microscopically, 22 tumors formed a morphologic spectrum intermediate between paraganglioma (PG) and neuroblastoma (NB). Others included two ganglioneuroblastomas (GNB), one lesion exhibited biphasic (neuronal and epithelial) differentiation, and one tumor showed predominantly epithelial features. Immunoreactivity for neuronal and neuroendocrine markers included synaptophysin in 77%, neurofilament protein in 38%, class III beta-tubulin in 81%, and chromogranin A in 77%. In 88% of cases, elongated S-100 protein-positive cells surrounded tumor lobules. Cytokeratin and epithelial membrane antigen immunoreactivity were noted in six (23%) and two (8%) tumors, respectively. Aberrant p53 expression was detected in 16 tumors (62%). The Ki-67 labeling index (LI) varied from 0%–43.8% (mean, 7.4%). Ultrastructurally, 80–230 nm dense core granules were noted within perikarya and as in microtubule-containing processes in all of the 11 tumors studied by electromicroscopy. Lobules of seven tumors were surrounded by electron-dense sustentacular cells. Epithelial tumors exhibited obviously epithelial features in addition to neuronal differentiation. DNA flow cytometry demonstrated a high incidence of polyploidy and aneuploidy (78%) and a wide range of percent S phase fractions (1.5%–21.8%; mean, 9.0%). The study showed that longer survival rates are related significantly to (1) the occurrence of metastases which was linked to tumor subtype, (2) to a higher incidence of S-100 protein-positive cells, and (3) to a low (<10%) Ki-67 labeling index. Conclusions. The present study indicates that (1) although typical olfactory neuroblastomas exhibit PG/NB differentiation, they more closely resemble PG, (2) occasional tumors show GNB and/or epithelial differentiation, and (3) survival rates may correlate with S-100 protein immunoreactivity and Ki-67 LI.

Studies on the regulation of the neutrophil chemotactic response using a rapid and reliable method for measuring random migration and chemotaxis of neutrophil granulocytes

AbstractsAn economic and sensitive test system for measuring random and directional migration of human neutrophils is described. The technique, based on a modified Boyden chamber equipped with a two-filter system, permits a substantial reduction of both incubation time and sample volume. The influence of various technical factors such as the neutrophil concentration in the cell suspension, the incubation time of the chambers, the test concentration of activated plasma or serum, the presence of heparin, and the procedure for separating neutrophils from human peripheral blood, was investigated. Standardized procedures for measuring and reporting neutrophil chemotaxis are proposed.The method has been used to study the significance of factors regulating neutrophil migration such as cytotaxin inactivators and neutrophil immobilizing factors (NIF). Activity of cytotaxin inactivators as assessed in undiluted serum or plasma at pH 7.4, 6.0 or 4.0 was very low. In contrast, potent neutrophil immobilizing activity was found in human serum or diluted plasma. These factors which inhibit migration were accordingly termed neutrophil immobilizing factors of plasma (NIF-P) and neutrophil immobilizing factor of serum (NIF-S). These factors are heat-stable, non-dialysable and of high molecular weight.

Hormonotherapy of meningiomas with medroxyprogesterone acetate: Immunohistochemical demonstration of the effect of medroxyprogesterone acetate on growth fractions of meningioma cells using the monoclonal antibody Ki-67

The effect of medroxyprogesterone acetate (MPA) on growth fractions of ex vivo meningiomas is demonstrated in using the Ki-67 monoclonal antibody in three cases of meningiomas operated on in two stages and in meningioma specimens from a group of eight patients operated on in one single stage after MPA therapy. Growth fractions in samples from five meningioma patients not treated with MPA were determined for comparison. In the three cases of two-stage operation of the tumors, the percentage of Ki-67-positive cells in meningioma tissue was lower by a factor of 6, 5, and 3, respectively, after MPA therapy. In meningioma specimens from patients receiving no MPA therapy, Ki-67-positive cells were present in 1.02 +/- 0.48%; in samples from MPA-treated tumors the percentage of Ki-67-positive cells was 0.41 +/- 0.40 (different at p less than 0.02 [Wilcoxons test]). In comparison to our previously published data on untreated meningiomas analyzed for progesterone receptors (PR), MPA significantly reduced the PR activity. There was no obvious correlation between PR activity and potential suppression of the tumor growth fraction. It is concluded that MPA is attractive because it reduces the growth fractions of most meningiomas and might be suitable for adjuvant hormonotherapy.

Autoantibody-Associated Sensory Neuronopathy and Intestinal Pseudo-Obstruction without Detectable Neoplasia

A 60-year-old patient presenting with the typical features of progressive sensory neuronopathy and subsequent intestinal pseudo-obstruction was found to have antineuronal nuclear antibodies (ANNA-I or Anti-Hu). These findings were suggestive of a paraneoplastic syndrome, but neither clinically nor at autopsy could a neoplasm be detected. Neuropathological findings were identical with those known for carcinoma-associated forms with marked neuron loss of spinal sensory ganglia and myenteric plexus. Therefore, ANNA-I and intestinal pseudo-obstruction may in rare cases occur without detectable underlying cancer.

Carcinosarcoma of the urinary bladder: A distinct variant characterized by small cell undifferentiated carcinoma with neuroendocrine features

The clinicopathological features of two carcinosarcomas of the urinary bladder are reported. The tumours occurred in a 64- and a 66-year-old patient presenting with haematuria and both were polypoid. The epithelial component was consistent with small cell undifferentiated carcinoma with neuroendocrine differentiation, whereas the sarcomatous component did not display specific features. The carcinomatous component showed immunohistochemical reactivity for different epithelial markers as well as for chromogranin and neuron specific enolase. Conversely, the sarcomatous cells stained strongly for vimentin and in one case for muscle actin and smooth muscle actin. The differential diagnosis of biphasic tumours of the bladder is discussed and the literature reviewed.

Decay-accelerating factor in the cardiomyocytes of normal individuals and patients with myocardial infarction

The presence of decay-accelerating factor (DAF) was clearly demonstrated on the surface of normal cardiomyocytes. In patients who had died of myocardial infarction (MI) cardiomyocytes displayed different appearances: outside the ischaemically damaged region the myocytes showed no significant variations in DAF expression when compared with controls without MI. Within myocardial zones damaged by ischaemia, however, apparently normal myocytes showed large gaps in surface staining of DAF or formed clusters which were entirely devoid of reactivity with anti-DAF antibodies. The number of DAF-deficient myocytes increased with the extent of necrosis and also with the number of days between onset of MI and death. Even though injury to myocytes is to a large extent related to anoxia and to the presence of free oxygen radicals, the complement system also appears to be involved; DAF may have protective functions against complement-mediated injury. We speculate that phospholipase may be involved in the removal of DAF from the cardiomyocyte surface.

Age-related Involution and Terminal Disorganization of the Human Thymus

The terminal involution pattern of the human thymus was studied based on autopsy cases (both sexes, age range 63-91 years). Large sections through the entire thymic fat body were examined with the help of both conventional histological and immunohistochemical techniques. The findings demonstrate that thymic atrophy in old humans (a) goes far beyond the degree of involution observed in small rodents; (b) results in a system of thin, branching, in part interrupted, non-keratinizing epithelial plates containing no typical Hassall bodies; (c) concerns all components of the thymus except fat tissue which progressively replaces original thymic structures; and (d) involves various types of disorganization of individual lobules with T and B lymphocytes often located outside rather than within epithelial remnants. Effects of low-level radiation on this final regression of the human thymus are unknown.

OUTCOME IN IDIOPATHIC CHILDHOOD NEPHROTIC SYNDROME A 20 Year Experience

112 patients with idiopathic childhood nephrotic syndrome have been referred from 1970 through 1989 at the Department of Pediatrics, University of Berne. One patient remitted spontaneously without medication. Ninety-eight patients responded to prednisone: 15 had a single bout of nephrosis, 47 developed a tendency towards relapses and 36 steroid dependence. In 28 patients with tendency towards relapses cure took place on either prednisone alone or prednisone plus cyclophosphamide. In 18 patients with steroid dependency cure took place on prednisone alone or prednisone plus cyclophosphamide. Thirteen patients failed to respond to steroids. The course of the disease was more benign in 68 patients with minimal change disease as compared with 14 patients with focal and segmental glomerular sclerosis. Immunofluorescence studies demonstrated mesangial IgM deposits in 14 out of 54 patients, but this finding was not a marker for poor steroid response or progression to renal failure. The course of the disease was especially unfavourable in patients with persisting nephrosis on completion of the initial course of steroid therapy. In conclusion it appears appropriate to define the disease in terms of steroid responsiveness as steroid resistant patients sometimes show normal glomeruli, steroid responsive sometimes have focal and segmental glomerular sclerosis or mesangial IgM deposits, and decisions depend more on the steroid responsiveness than on the histological features.

Heterogeneous malignant non Hodgkin's lymphomas as a causative disorder in lethal midline granuloma.

The present report describes the results of a combined morphological, enzyme- and immunohistochemical analysis of nine cases of malignant non Hodgkins lymphomas (NHL) clinically presenting as lethal midline granuloma. In a previous report written before antibodies directed against B and T lymphocytes were available, a histiocytic origin of such neoplasms had been suggested. A panel of antibodies reactive with most B cells (L26, MB1, KiB3) and a majority of T cells (MT1, UCHL1) was applied on paraffin sections of formalin fixed tissues as well as antibodies directed against leukocyte common antigen (LCA), myeloid/histiocyte antigen (MAC 387), lysozyme, alpha-1-antitrypsin, alpha-1-antichymotrypsin, S-100 protein, prekeratin and immunoglobulin light chains. Enzyme histochemistry included tests for non-specific acid esterase, acid phosphatase, betaglucuronidase and chloroacetate esterase. As a result, five T, two B and two unclassified (malignant histiocytosis probable) NHL were identified, indicating distinct heterogeneity of NHL as causative disorders in lethal midline granuloma.