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Showing papers by "John Q. Trojanowski published in 1990"


Journal ArticleDOI
TL;DR: Differences between the complement of beta-APP, tau, and NF protein epitopes in AD versus non-AD brains implicate a defect involving one or more steps in the posttranslational modification, degradation, or elimination of these proteins in AD brains, and this may account for the massive numbers of SPs that characterize AD.
Abstract: Eight antisera and one monoclonal antibody to synthetic peptides that corresponded to domains extending over the entire length of the beta-amyloid precursor protein (beta-APP), and an antiserum to the full-length 695-amino acid form of the beta-APP, were raised to probe the composition of the core and corona of senile plaques (SPs). We localized distinct beta-APP domains, including the beta-amyloid protein or A4 region, within the SPs of 13 end-stage Alzheimer disease (AD) and 13 age-matched control samples of hippocampus and entorhinal cortex. The composition of SPs also was probed with antibodies to defined epitopes in tau (tau) as well as the large and mid-size neurofilament (NF) proteins. The most important observations were that beta-APP domains outside the A4 region were largely restricted to SP coronas in the AD samples, together with tau and NF determinants, whereas the same epitopes were absent from A4-positive blood vessels and exceptionally rare in non-AD SPs. Indeed, samples from a subset of the non-AD cases contained a considerable number of A4-positive SPs totally devoid of any of the other beta-APP, tau, and NF epitopes. These observations suggest that the deposition of the A4 protein in AD SPs results from the local processing of beta-APPs in association with tau and NF protein fragments. It is unclear whether this association is fortuitous or linked by common mechanisms. However, differences between the complement of beta-APP, tau, and NF protein epitopes in AD versus non-AD brains implicate a defect involving one or more steps in the posttranslational modification, degradation, or elimination of these proteins in AD brains, and this may account for the massive numbers of SPs that characterize AD.

157 citations


Journal ArticleDOI
TL;DR: Lower motor neurons of the spinal cord of patients with amyotrophic lateral sclerosis, Werdnig-Hoffmann's disease, X-linked recessive bulbospinal neuronopathy and multiple system atrophy were immunohistochemically examined by using a monoclonal antibody (Ta-51) specific to phosphorylated epitopes of high molecular weight subunits of neurofilaments.
Abstract: Lower motor neurons of the spinal cord of patients with amyotrophic lateral sclerosis (ALS), Werdnig-Hoffmann's disease (WH), X-linked recessive bulbospinal neuronopathy (X-BSNP) and multiple system atrophy (MSA), all of which were known to involve the lower motor neurons, were immunohistochemically examined by using a monoclonal antibody (Ta-51) specific to phosphorylated epitopes of high molecular weight subunits of neurofilaments. The incidence of Ta-51-positive neurons was significantly increased in ALS, WH and MSA, but not in X-BSNP. Ta-51-positive neurons showed a wide variety of morphological appearances, including neurons with normal appearance, central chromatolysis, simple atrophy and neurons containing massive neurofilamentous accumulation. In aged-control cases, similar Ta-51-positive neurons were observed, although to a much lesser extent. In ALS, spheroids and globules, which were strongly positive for Ta-51, were also significantly increased. Ta-51-positive motor neurons, spheroids and globules appeared in proportional to the number of remaining large motor neurons in ALS.

128 citations


Journal Article
TL;DR: The consistent expression of synaptophysin and 2 or more neuropeptides indicates that central nervous system PNETs have significant phenotypic features in common with neuroendocrine tumors.

75 citations


Journal Article
TL;DR: It is indicated that tau epitopes are more abundant than NF epitopes in NFTs and that the formation of N FTs may be linked to a derangement in the normal metabolism of tau that is more extensive than alterations in NF protein metabolism.
Abstract: Neurofibrillary tangles (NFTs) derive, in part, from normal neuronal cytoskeletal proteins, ie, large portions of tau (tau) but only restricted segments of the peripheral domains of the high- and middle-molecular weight neurofilament subunits. To learn more about the events leading to the incorporation of tau and neurofilament epitopes into NFTs, the relative abundance of tau and NF determinants in these lesions was quantitatively analyzed in hippocampi from Alzheimer disease (AD) patients and age-matched controls using monoclonal antibodies specific for tau or for NF proteins. Immunostained NFTs appeared qualitatively the same in both AD and controls, ie, every epitope found in AD NFTs occurred also in the NFTs of the control patients. However, in hippocampi with only a few tangles, tau epitopes, but no NF epitopes, were detected in NFTs. In contrast, both tau and NF epitopes were present in those tangles that were found in hippocampi with abundant NFTs. Nevertheless, the number of tau-positive NFTs generally exceeded the number of NF-positive NFTs. These findings indicate that tau epitopes are more abundant than NF epitopes in NFTs and that the formation of NFTs may be linked to a derangement in the normal metabolism of tau that is more extensive than alterations in NF protein metabolism.

64 citations


Journal ArticleDOI
TL;DR: Three important conclusions emerge from this study: internalization of NGFRs is not necessary for some early rapid transcriptional effects of NGF, an unknown factor(s) that cooperates with the cloned NGFR in allowing high-affinity NGF binding is found in a primitive central nervous system cell line, andNGFRs introduced into and expressed by D283 MED are unable to induce differentiation in these primitive neuron-like tumor cells.
Abstract: Expression of the cloned human nerve growth factor receptor (NGFR) cDNA in cell lines can generate both high- and low-affinity binding sites. Since the inability to respond appropriately to differentiation factors such as NGF may contribute to determining the malignant phenotype of neuroblastomas, we sought to determine whether the same is true of medulloblastomas. To generate a human central nervous system neuronal cell line that would respond to NGF, we infected the medulloblastoma cell line D283 MED with a defective retrovirus carrying the cDNA coding for the human NGFR. The resultant cells (MED-NGFR) expressed abundant low- and high-affinity NGFRs, and NGF treatment induced a rapid transient increase of c-fos mRNA in the NGFR-expressing cells but not in the parent line or in cells infected with virus lacking the cDNA insert. However, the MED-NGFR cells did not internalize the NGFR at high efficiency, nor did they differentiate in response to NGF. Three important conclusions emerge from this study: (i) internalization of NGFRs is not necessary for some early rapid transcriptional effects of NGF; (ii) an unknown factor(s) that cooperates with the cloned NGFR in allowing high-affinity NGF binding is found in a primitive central nervous system cell line; and (iii) NGFRs introduced into and expressed by D283 MED (i.e., MED-NGFR) cells are partially functional but are unable to induce differentiation in these primitive neuron-like tumor cells, implying that high-efficiency receptor-mediated endocytosis of NGF and its receptor may be a necessary step in the cascade of events leading to NGF-mediated differentiation.

63 citations



Journal Article
TL;DR: The above-outlined neuronal profile of peripheral neuroblastic tumors, including NBs, distinguishes this group of tumors from the much-less neuronally differentiated primitive neuroectodermal tumors of the central nervous system.
Abstract: To establish the neuroendocrine and neural features of peripheral neuroblastic tumors, a prospectively collected group of 12 neuroblastomas (NB), 2 ganglioneuroblastomas (GNB), and 4 ganglioneuromas (GN) was probed with a panel of monoclonal antibodies (MAbs) to neuroendocrine and neural antigens. All tumors expressed the pan-neuroendocrine markers synaptophysin and chromogranin A. They also showed extensive expression of neuronal antigens, ie, of each of the neurofilament (NF) triplet proteins and of the microtubule-associated proteins (MAPs) MAP2 and tau-protein. However, only in the GNBs and GNs was the pattern of NF phosphoisoforms relatively mature. In the latter tumors glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP) could be demonstrated as well, suggesting the presence of nonmyelinating and myelinating Schwann cells, respectively. The glial markers did not colocalize with the neural markers. On the basis of these data, it was concluded that all peripheral neuroblastic tumors manifest molecular characteristics of neuroendocrine cells and of neurons. The latter were most developed in GNBs and GNs, in which they were accompanied by Schwann cell differentiation in a separate population of cells. The above-outlined neuronal profile of peripheral neuroblastic tumors, including NBs, distinguishes this group of tumors from the much-less neuronally differentiated primitive neuroectodermal tumors of the central nervous system.

57 citations


Journal ArticleDOI
TL;DR: Observations indicate that chromaffin and ganglion cells establish their immunophenotype early in embryogenesis, and suggest that "large" and "small" cells are progenitors of the chromAffin and the ganglions cells, respectively, of the mature adrenal medulla.

55 citations


Journal ArticleDOI
TL;DR: Antibodies to the Alzheimer disease β‐amyloid peptide were used to identify βAP precursor fragments in blood and these data are significant for efforts to develop immunochemical assays to diagnose and monitor the progression of AD.

39 citations


Journal ArticleDOI
01 Mar 1990-Cancer
TL;DR: The results suggest that for NE neoplasms of the GIT and pancreas the differential expression of NF subtypes appears to be related to tumor site; and CR is a marker of most G IT and pancreaticNE neoplasm although NF may discriminate subtypes of GITand pancreatic NE tumors.
Abstract: To differentiate neuroendocrine (NE) neoplasms arising at different levels of the gut and pancreas, the authors studied the expression of neurofilament (NF) proteins and chromogranin (CR) in normal and neoplastic NE cells of the human gastrointestinal tract (GIT) (14 ileal/jejunal carcinoids, six appendiceal carcinoids, 11 rectal carcinoids) and pancreas (23 islet cell tumors). Among pancreatic islet cell tumors, those with middle molecular weight (NF-M)-positive cells were more abundant than those with high molecular weight (NF-H)-positive cells; nearly all of these tumors expressed CR. Although NF-M was abundantly expressed in greater than 50% of tumor cells in a subset of these tumors, only one of these tumors exhibited diffuse immunoreactivity with NF-H. Among rectal carcinoid tumors, NF-M and NF-H-positive cells were present in approximately the same number of tumors, yet only diffuse immunoreactivity to NF-H could be detected. Chromogranin immunoreactivity in greater than 50% of tumor cells was present in 74% of islet cell tumors, 93% of ileojejunal carcinoids, and 83% of appendiceal carcinoids, but only in a minority of rectal carcinoids (36%). Although ileojejunal carcinoid tumors rarely expressed NF-M and did not express NF-H, diffuse immunoreactivity with CR was present in nearly all of these tumors. None of the appendiceal carcinoid tumors expressed NF-M or NF-H, yet all of these tumors demonstrated immunoreactivity with CR. Neurofilament immunoreactivity was not detected in normal GIT and pancreatic NE cells, whereas CR immunoreactivity was always present. These results suggest that for NE neoplasms of the GIT and pancreas the differential expression of NF subtypes appears to be related to tumor site; and CR is a marker of most GIT and pancreatic NE neoplasms although NF may discriminate subtypes of GIT and pancreatic NE tumors. Neurofilament subtyping may be useful in the evaluation of the origin of NE tumors presenting as metastatic lesions.

30 citations


Journal Article
TL;DR: Investigation of frozen, unfixed tissue sections from 56 poorly differentiated, non-small cell primary lung tumors concluded that immunohistologic evidence of NE differentiation is present in a significant proportion of pulmonary large cell and poorly differentiated adenocarcinomas and rare in poorly differentiated squamous carcinomas.

Journal ArticleDOI
TL;DR: Although CHP707m is the first central nervous system PNET cell line proven to express NGF receptors, immunohistological survey of tissue sections prepared from human central nervous System PNETs showed that 13 of 35 contained NGF receptor‐positive tumor cells, suggesting more than one‐third of such tumors might be responsive to the effects of NGF.
Abstract: A primitive neuroectodermal tumor (PNET) presented as a cerebral hemispheric mass in a 33-year-old man. Bone marrow metastases were discovered 11 months later. A cell line (CHP707m) was derived from these metastases. In culture, the cells showed features of neuronal differentiation, forming short neurites and synthesizing low-molecular-weight neurofilament protein. Northern blotting showed the tumor cells express nerve growth factor (NGF) receptor messenger RNA, and fluorescence-activated cell-sorting demonstrated NGF receptors on the cell surface. Western blotting showed CHP707m NGF receptors are truncated. The receptors are functional; they bind iodine 125-labeled mouse NGF with an affinity of 1.6 x 10(-9) M, and short-term treatment with NGF induces expression by the tumor cells of the proto-oncogene, c-fos. Although CHP707m is the first central nervous system PNET cell line proven to express NGF receptors, immunohistological survey of tissue sections prepared from human central nervous system PNETs showed that 13 of 35 contained NGF receptor-positive tumor cells. Thus, more than one-third of such tumors might be responsive to the effects of NGF.