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Biomedical subjects

T Kitamoto

Publications and source records attributed to T Kitamoto.

At least 145 records · Page 8Linked to original sources

Ferritin immunohistochemistry as a marker for microglia.

An immunohistochemical analysis of formalin-fixed, paraffin-embedded brain sections was performed with antisera against holoferritin and the light(L)-subunit of ferritin. Sections immunostained using anti-glial fibrillary acidic protein (GFAP), Ricinus communis agglutinin-1 (RCA-1) stain for microglia and iron stain (Berlin blue stain) were compared. The L-subunit of ferritin was purified from normal human spleen according to the modified scrapie-associated fibrils purification, and the anti-serum was raised in a rabbit. Both ferritin antisera positively stained resting and, more markedly, reactive microglia, both of which were also stained with RCA-1 but not with GFAP. Ferritin-positive resting microglia were seen more abundantly in cerebral and cerebellar cortices than in white matter. The advantages of ferritin antisera over RCA-1 are as follows. (1) RCA-1 heavily stains blood vessels, while anti-ferritin does not, hence the microglial cells are more readily visualized with ferritin immunohistochemistry. (2) Reactive microglia and macrophages are more strongly stained with anti-ferritin. (3) The staining intensity of ferritin is independent of the length of tissue fixation in formalin. However, anti-ferritin is inferior to RCA-1 in staining resting microglia with a scanty cytoplasm, especially in the white matter, probably because the former recognizes cytoplasmic components, while the latter recognizes cell membrane. Iron stain only gave a reaction to microglial cells in brains with neurosyphilis and to hemosiderin-laden macrophages. Thus, in addition to RCA-1, ferritin antisera are useful as a microglia marker in formalin-fixed, paraffin-embedded sections.

Brain↗

Organ distribution of proteinase-resistant prion protein in humans and mice with Creutzfeldt-Jakob disease.

We attempted to clarify the organ distribution of human and murine proteinase-resistant prion protein (PrPCJD) in Creutzfeldt-Jakob disease (CJD), and to measure the concentration of PrPCJD, using a semi-quantitative Western blot analysis. Human PrPCJD was restricted to the central nervous system, whereas murine PrPCJD was present in the central nervous system and in the lymphoreticular system at the end stage of CJD. PrPCJD concentration in the central nervous system of mice was almost identical to that of humans. The minimum wet weight of an organ with a positive reaction was 0.3 mg for brain, 1 to 3 mg for spleen, 3 mg for spinal cord, 3 mg for lymph node, 10 mg for thymus and 10 to 30 mg for intestine of the CJD-infected mice. There were no immunoreactions in purified PrPCJD fractions from 300 mg of spleen, lymph node, liver or peripheral nervous systems of humans, nor in 300 mg of liver, lung or kidney of CJD-infected mice. Within the limits of our method, the distribution of murine PrPCJD differed from that of human PrPCJD. Antibodies on the Western blot membrane from murine spleen PrPCJD fractions stained the kuru plaques in the CJD-infected mouse brain. Therefore, PrPCJD in the murine spleen probably shares the epitopes of the antigen in the murine kuru plaques. Although the immunological detection of PrPCJD does have limits of sensitivity, PrPCJD concentrations did correlate with infectivity titres in scrapie-infected or CJD-infected mice.

Animals↗

Beta-protein amyloid is widely distributed in the central nervous system of patients with Alzheimer's disease.

To clarify the distribution, morphology, and density of amyloid deposits in patients with Alzheimer's disease (AD), tissue sections from various areas of the central nervous system of 14 patients with AD and from 20 nondemented aged controls were investigated immunohistochemically using anti-beta protein antiserum. beta-protein amyloid deposits were present not only in the cores of the senile plaques and in the vascular wall (amyloid angiopathy), but also in various sized plaque-shaped fibrillary, perivascular, subpial, and subependymal deposits. Amyloid deposits were found mainly in the cerebral cortex in nondemented controls, while in AD they were distributed widely in the regions that were not affected in nondemented controls. The positivity of amyloid deposits in AD was 100% in the cerebral cortex, hippocampus, amygdala, thalamus, caudate nucleus, claustrum, hypothalamus, nucleus basalis of Meynert, and cerebellar cortex. Putamen and brain-stem nuclei were affected frequently, and the spinal cord, dentate nucleus, and globus pallidus were sometimes (less than 50%) affected. This result provides an evidence that Alzheimer's disease is a beta-protein amyloidosis of the central nervous system. An assessment of the distribution of amyloid deposits should prove to be useful for the histopathologic diagnosis of AD.

Aged↗

Positive transmission of Creutzfeldt-Jakob disease verified by murine kuru plaques.

Kuru plaque is a pathognomonic feature in the brain of patients with Creutzfeldt-Jakob disease (CJD) and in the brain of CJD-infected mice. Kuru plaques from CJD-infected mice were immunolabeled with rabbit anti-murine prion protein (PrP) absorbed with human PrP, but not so with mouse anti-human PrP. Therefore, the murine kuru plaque is composed of the host (mouse) PrP and can be distinguished antigenically from human PrP. Immunostaining using the anti-murine PrP and formic acid enhancement on tissue sections revealed not only birefringent kuru plaques but also nonbirefringent diffuse and small PrP accumulations. This immunohistochemical detection of kuru plaques provides more positive evidence than heretofore employed histochemical approaches. There were kuru plaques in brains of the first passage mice inoculated with tissues from 30 (91%) of 33 patients with CJD, the 3 negative patients belonging to a type of Gerstmann-Sträussler syndrome. Tissues from 6 other demented patients did not produce kuru plaques. In the evaluation of spongiform changes, mice inoculated with tissues from 23 (70%) of 33 patients were considered cases of successful transmission. In some mice, kuru plaques were present in the absence of spongiform changes. Further inoculations from 9 mice with kuru plaques but no spongiform changes were successful in almost all mice. Therefore, mice with murine kuru plaques in the absence of spongiform changes are also infectious. Thus, the presence of murine-specific kuru plaques can serve as another hallmark of a successful transmission.

Adult↗

Increased tau accumulation in senile plaques as a hallmark in Alzheimer's disease.

To identify the tau component in senile or kuru plaques, the authors examined brain sections from 12 patients with Alzheimer's disease (AD), 6 with Creutzfeldt-Jakob disease (CJD), and 20 nondemented aged controls using anti-beta protein, anti-buman prion protein, and affinity-purified tau-specific antibody. The tau component was identified both in senile and kuru plaques. In AD, tau-positive senile plaques were found in all cerebral cortices of almost all cases, and the tau-positivity of plaques in cerebral cortices was 5.1 to 27.5%. In CJD, tau-positive senile and kuru plaques were restricted to the hippocampus, and the tau-positivity was 4.3 and 1.2%, respectively. In nondemented aged controls, tau-positive senile plaques also were restricted mostly to the hippocampus, and the tau-positivity was 1.3%. Significant differences in the tau-positivity of senile plaques were found between AD and CJD and nondemented aged controls, and no significant differences were found between CJD and nondemented aged controls. These observations are important because increased tau accumulation in senile plaques can be a hallmark of AD.

Adult↗

The presence of a novel cellular retinoic acid-binding protein in chick embryos: purification and partial characterization.

Two cellular retinoic acid binding proteins, CRABP I and II, which behaved differently on a DEAE-cellulose column, were purified from 14-day chick embryos. Their molecular weights were 15.8 kDa and 16.2 kDa, respectively. NH2-terminal 36 amino acid sequence of CRABP I was identical to that of bovine CRABP, which was reported previously. CRABP II was a novel cellular retinoic acid binding protein, in which the amino acids at 6 positions of the NH2 terminal sequence are different from those in CRABP I. The homology between CRABP I and II was more than 83%.

Amino Acid Sequence↗

Structure of fatty acid synthetase from the Harderian gland of guinea pig. Proteolytic dissection and electron microscopic studies.

Limited proteolysis and electron microscopic observation of fatty acid synthetase from the Harderian gland of guinea pig was performed to elucidate the higher-order structures of this multifunctional protein. Staphylococcus aureus V8 protease dissected the 250,000 Mr subunit of fatty acid synthetase into 120,000, 70,000, 35,000 and 30,000 Mr fragments, which were aligned in this order from the NH2 terminus. Some of the protease-resistant fragments produced with elastase, trypsin and lysyl endopeptidase were purified and fragment-specific antibodies (A40L, A33E and A25T) were prepared. A25T and A33F specifically bound the 35,000 and 30,000 Mr fragments, and A40L recognized the region between the 120,000 and 70,000 Mr fragments. Electron microscopic studies employing rotary shadowing, unidirectional shadowing and negative staining revealed that the overall dimension of the enzyme was 22 nm x 15 nm x 7 nm, and that two elongated subunits mainly composed of three subregions were in contact with each other at a few, three at most, points with two holes between them. The outer two attachment sites were often not in contact, indicating a certain flexibility of subunits at their ends. Immunocomplexes composed of fatty acid synthetase and fragment-specific antibodies were isolated and observed under the electron microscope. The attachment sites of A40L and A33E were located at the end of the minor and the major axes of the ellipsoidal contour of the molecule, respectively. Based on these results, the three-dimensional structure of animal fatty acid synthetase is discussed.

Amino Acid Sequence↗

Gerstmann-Sträussler-Scheinker disease: immunohistological and experimental studies.

The older brother of the patient from whom the Fukuoka-1 strain was isolated was found to have numerous kuru plaques, the main finding common to both siblings. Other clinicopathological features including spongiform change were absent in the older brother. Immunostaining using anti-kuru plaque core protein and anti-beta-protein peptide revealed many kuru plaques and a few senile plaques in the older brother. Experimental transmission of the disease to laboratory animals was successful, using tissues from both siblings, through inoculation of fresh brain homogenates, purified prion protein, and formalin-fixed brain homogenates. Prion protein fractions from the patient's brain shortened the incubation periods and formalin-fixed mouse brains did not lengthen the periods. The disease in the two brothers can be classified as Gerstmann-Sträussler-Scheinker disease, a familial variant of Creutzfeldt-Jakob disease. Gerstmann-Sträussler-Scheinker disease manifests a variety of clinicopathological features. Immunohistological verification of kuru plaques has major diagnostic value in assessing dementia.

Aged↗

Immunohistochemical verification of senile and kuru plaques in Creutzfeldt-Jakob disease and the allied disease.

We investigated paraffin-embedded brain sections from 41 patients with Creutzfeldt-Jakob disease (CJD) and from 9 with Gerstmann-Sträussler syndrome (GSS) using anti-human prion protein (PrP) antisera (anti-GSS kuru plaque cores and anti-PrP synthetic peptide) and anti-beta protein antiserum. The anti-human PrP antiserum reacted with the plaques in CJD and GSS, with or without degenerative neurites (neuritic components). In addition, the anti-beta protein antiserum immunolabeled kuru plaque-like compact plaques in some cases of CJD. Therefore, previous morphological classifications of the plaques may not always be valid. Senile plaques labeled with anti-beta protein antiserum were evident in 65% of the CJD brains and 50% of GSS brains from patients in their 60s, and in 73% of brains from CJD patients in their 70s, but not in brains from patients under 60 years of age. The incidence of the senile plaques was compatible with the normal aging process and was apparently not accelerated by the disease process of CJD or GSS. These immunostaining approaches using anti-human PrP and anti-beta protein antisera allow classification of plaque types and increase the reliability of the pathological diagnosis in persons with dementia.

Adult↗

Focal intracerebral accumulation of a novel type of amyloid protein. An early stage of cerebral amyloidoma?

The brain of a 60-year-old patient with bronchial carcinoma presented a focal amyloid deposit in the white matter associated with myelin and axonal destruction. An additional lesion was found in the basal ganglia. This silent focal intracerebral accumulation of amyloid substance may be a prestadium of a "cerebral amyloidoma". The histochemical and immunohistochemical analysis of the accumulated amyloid indicated that it may belong to a novel type of amyloid.

Amyloid↗

Renal amyloidosis. Correlations between morphology, chemical types of amyloid protein and clinical features.

Sixty-one autopsy cases of renal amyloidosis were reviewed to assess the relationship of renal pathology to chemical types of amyloid and clinical features. Glomerular amyloid deposition was divided on the basis of morphological characteristics, into four types: a mesangial nodular type showing nodular mesangial deposits with sparse capillary wall involvement (25 cases), a mesangio-capillary type disclosing diffuse amyloid deposition in the mesangium and along both sides of the glomerular basement membrane (19 cases), a perimembranous type principally involving the subepithelial side of the basement membrane invariably characterized by exuberant spicular arrangement (6 cases), and a hilar type showing amyloid deposits almost exclusively in hilar arterioles (11 cases). Twenty-four of 25 cases of mesangial nodular type (96%) showed amyloid protein of AA type. However, mesangio-capillary and perimembranous types were associated with deposition of AL amyloid protein in 15 of 19 (79%) and all 6 cases, respectively. Nephrotic syndrome was more frequent in patients with AL amyloidosis; notably, all patients with perimembranous type had nephrotic syndrome irrespective of the extent of glomerular amyloid deposits. Chronic renal failure and renal death appeared more common in mesangial nodular type in which the extent of glomerular amyloidosis correlated with that of vascular amyloid deposits. The results obtained suggest that the chemical type of glomerular amyloid protein (AA vs AL) is associated with significant differences in the morphological, clinical and prognostic features of the renal involvement.

Adult↗

Incidence and characterization of age related amyloid deposits in the human anterior pituitary gland.

To identify amyloid deposits in the anterior pituitary gland, we have immunohistochemical, histochemical and alkaline Congo red staining. The anti-human P component reacted positively with these amyloid deposits, while antisera against prealbumin, AA type amyloid fibril protein and various anterior pituitary hormones were negative. A combination of Congo red and anti-human P component staining was most sensitive and reliable for detection of amyloid in the anterior pituitary glands of 300 randomly autopsied patients. Amyloid deposits increased in parallel with the age of the patients, however, they appeared earlier and more frequently than heretofore reported. Deposition of amyloid was seen initially in the 3rd decade and the positivity rate of amyloid deposits was 73% in the 5th decade. The histochemical characteristics of these pituitary amyloid deposits differed from those of cerebral and systemic deposits, particularly those found in the amyloid of senile systemic amyloidosis.

Adolescent↗

Aging and cerebral amyloid: early detection of amyloid in the human brain using biochemical extraction and immunostain.

To search for relationships between aging and cerebral amyloid, the brains of 66 clinically nondemented individuals were investigated, using the following three approaches for verification of the amyloid: Congo red staining as a histochemical method; immunostaining using anti-beta protein antiserum as an immunohistochemical identification; and biochemical extraction of amyloid from nonfixed brain tissues. That the incidence of cerebral amyloid increased with aging was determined using all three approaches. Immunostaining using anti-beta protein antiserum was more sensitive than Congo red staining. The biochemical extraction was most sensitive for detection of amyloid, and revealed that amyloid was extracted initially from more than half (67%) of the brains of 9 persons in their 50s and from almost all (97%) brains of 35 persons over 60 years of age. Amyloid was extracted even from brains in which amyloid deposits were not detected by histochemical or immunohistochemical methods. This result shows early appearance of the age-related cerebral amyloid.

Aging↗

Choroid plexus papillomas: an immunohistochemical study with particular reference to the coexpression of prealbumin.

Immunocytochemical characterization of choroid plexus neoplasms was performed in seven cases, five being of benign choroid plexus papilloma (CPP) and the other two of malignant choroid plexus papilloma (choroid plexus carcinoma CPC). Immunohistochemical examination was performed with antibodies to glial fibrillary acidic protein (GFAP), S-100 protein, prealbumin, carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA), and gamma-enolase. All of the five CPPs were positive for GFAP, S-100, prealbumin, and gamma-enolase; and four of them were positive for EMA. None of the CPPs was positive for CEA. Both of the two cases of CPC were positive for gamma-enolase, and one was positive for GFAP, S-100, EMA, and CEA. No CPC showed positivity for prealbumin. This report is the first to describe the usefulness of prealbumin reactivity for histological diagnosis of choroid plexus papillomas.

Adolescent↗

Immunohistochemical confirmation of Creutzfeldt-Jakob disease with a long clinical course with amyloid plaque core antibodies.

Amyloid plaques have been found in the brains of some patients with Creutzfeldt-Jakob disease (CJD) and all patients with Gerstmann-Sträussler syndrome (GSS). We examined paraffin sections from 45 patients with CJD or GSS and from 51 patients with other neurologic diseases, using an antiserum against GSS amyloid plaque cores. The GSS amyloid plaque core antiserum revealed not only birefringent amyloid plaques but also small plaques that cannot be detected by the staining with Congo red dye. Positive immunolabeling was demonstrated in 59% of 34 Japanese patients with CJD, in 100% of 11 patients with GSS, and in none with other neurologic diseases. All cases of CJD of short duration (less than 11 months) were evaluated as being negative, and 95% of 21 long survivors (over 12 months) were positive. This immunohistochemical approach revealed that amyloid plaque is a hallmark of CJD with a long clinical course.

Amyloid↗

Choroidal epithelial cyst of the cerebral hemisphere. An immunohistochemical study.

A case of choroidal epithelial cyst in the left cerebral hemisphere of a 4-month-old infant is described. The cyst wall was composed of a single epithelial layer with a basement membrane and fibrous connective tissue. An immunohistochemical study revealed the presence of prealbumin in the cytoplasm of these cuboidal epithelial cells. This fact strongly suggested that the cuboidal epithelium lining the cyst wall originated from choroidal epithelial cells. The diagnostic usefulness of the immunohistochemical study in choroidal epithelial cysts is discussed.

Choroid Plexus↗