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S Kotani

Publications and source records attributed to S Kotani.

At least 91 records · Page 5Linked to original sources
PubMed1988

Isolation of rat liver microtubule-associated proteins. Evidence for a family of microtubule-associated proteins with molecular mass of around 200,000 which distribute widely among mammalian cells.

Heat-stable microtubule-associated proteins (MAPs) were isolated from rat liver crude extract. The most prominent species showed a molecular mass close to that of bovine adrenal 190-kDa MAP (Kotani, S., Murofushi, H., Maekawa, S., Sato, C., and Sakai, H. (1986) Eur. J. Biochem. 156, 23-29), termed rat 190-kDa MAP. Immunological studies with antiserum against the rat 190-kDa MAP showed that this MAP exists in a variety of rat cells and tissues. The characteristics of the rat 190-kDa MAP, including molecular mass, heat stability, and distribution pattern, were very similar to those of bovine adrenal 190-kDa MAP. However, one-dimensional peptide mapping revealed considerable difference, and there is little mutual immunological cross-reactivity. We also identified in mouse neuroblastoma Neuro 2a cells a MAP of around 200 kDa which is considered to be MAP4 (Parysek, L. M., Asnes, C.F., and Olmsted, J.B. (1984) J. Cell Biol. 99, 1309-1315). MAP4 was slightly immunoreactive to both anti-(rat 190-kDa MAP) antiserum and anti-(bovine 190-kDa MAP) antiserum. Taking these results together, we conclude that mammalian tissues ubiquitously contain heat-stable MAPs of 200 kDa and that these 200-kDa MAPs should be considered as species-specific homologues.

Animals↗
PubMed1988

Milk-borne transmission of human T-cell leukemia virus type I in rabbits.

The mode of vertical transmission of human T-cell leukemia virus type I (HTLV-I) was investigated by foster-nursing in rabbits. Two of five rabbits born to noninfected mothers and fostered by virus-infected females seroconverted for HTLV-I after 7 weeks, whereas all seven rabbits born to virus-infected mothers and fostered by noninfected females remained seronegative for the observation period of 6 months. Culture of peripheral blood lymphocytes gave rise to an HTLV-I-carrying T-cell line from each of the two seroconverted rabbits. These findings suggest that HTLV-I is transmitted through milk from mother to offspring.

Animals↗
PubMed1988

Antitumour effects of streptococcal lipoteichoic acids on Meth A fibrosarcoma.

The antitumour effects of lipoteichoic acids (LTA) extracted from Streptococcus pyogenes were studied in comparison with other streptococcal cellular components. LTA suppressed the tumour growth of both solid- and ascites-type Meth A fibrosarcoma as did the whole cells of S. pyogenes (OK-432). No other cellular components, such as cell wall peptidoglycan, group-specific C-carbohydrate or type-specific M protein, suppressed the growth of Meth A. LTA, but not the other cellular components, induced tumour necrosis factor (TNF) in Propionibacterium acnes-primed mice. LTA had no direct killing effects on Meth A cells. These results indicate that LTA may be an important antitumour component of OK-432 and that one of the antitumour mechanisms by this streptococcal preparation is the induction of TNF.

Animals↗
PubMed1988

Immunohistochemical identification of Trichosporon beigelii in histologic section by immunoperoxidase method.

An indirect immunoperoxidase method capable of identifying an opportunistic fungus, Trichosporon beigelii, in formalin-fixed, paraffin-embedded tissue has been developed. The authors studied autopsy materials from 19 patients with various fungal infections, including 3 patients with disseminated T. beigelii infection, 8 patients with localized or systemic candidiasis, 4 patients with invasive aspergillosis, 2 patients with pulmonary mucormycosis, and 2 patients with systemic cryptococcosis. T. beigelii could be successfully visualized in tissue sections from all three patients with this infection and a patient with systemic candidiasis who was found to have concomitant infection by T. beigelii. The capsule of Cryptococcus neoformans was also stained, indicating the presence of cross-reactive antigen between T. beigelii and C. neoformans. C. neoformans-absorbed antiserum was reactive with T. beigelii but not with other fungi, including C. neoformans.

Antibodies, Fungal↗
PubMed1988

Immunobiological activities of a porin fraction isolated from Fusobacterium nucleatum ATCC 10953.

From Fusobacterium nucleatum ATCC 10953 cell envelope fraction whose inner membranes had been removed by treatment with sodium N-lauroyl sarcosinate, an outer membrane protein (37,000 Mr in a native state) was prepared by extraction with lithium dodecyl sulfate. The protein thus obtained showed distinct porin activity, namely, the ability to form hydrophilic diffusion pores by incorporation into the artificial liposome membrane. The porin fraction exhibited strong immunobiological activities in the in vitro assays: B-cell mitogenicity and polyclonal B-cell activation on murine splenocytes, stimulatory effects on guinea pig peritoneal macrophages, and enhancement of the migration of human blood monocytes. The porin fraction also exhibited immunoadjuvant activity to increase the antibody production against sheep erythrocytes in the spleen of mice that were immunized by sheep erythrocytes with porin. Although chemical analyses revealed that the test porin fraction contained a considerable amount of lipopolysaccharide (LPS) (around 12% of the fraction), the studies with LPS-nonresponding C3H/HeJ mice and on the inhibitory effects of polymyxin B strongly suggest that most of the above bioactivities are due to porin protein itself, not to coexistent LPS in the porin fraction.

Adjuvants, Immunologic↗
PubMed1988

Structural requirements of endotoxic lipopolysaccharides and bacterial cell walls in induction of interleukin-1.

A variety of compounds, synthetic, semisynthetic or bacterial, which corresponds to structural components of endotoxic lipopolysaccharides (LPS) and bacterial cell wall peptidoglycans were studied for their activity to enhance interleukin-1 (IL-1) production of murine peritoneal macrophages and the ability to activate the complement cascade in fresh adult human serum. Not only bacterial LPS and cell walls or peptidoglycans but also their structural components with appropriate size and structure induced IL-1 production by macrophages and activated the human complement cascade, which may lead to the IL-1 production by monocytes/macrophages.

Animals↗
PubMed1988

Dual effect of antimitotic drugs on steroid secretion in mouse adrenocortical Y-1 tumor cells.

Mouse adrenocortical Y-1 tumor cells were examined in a monolayer culture and their steroid secretion was measured. The Y-1 cells constantly released a small amount of steroids in the absence of adrenocorticotropin (ACTH). When synthetic ACTH (tetracosactide acetate) was added to the medium, an increase in the steroid secretion of approximately 5-fold was observed. The Y-1 cells also showed a typical cytoplasmic retraction in response to ACTH. Incubation of the cells with an antimitotic drug, colchicine, prior to ACTH-stimulation resulted in a 30-50% reduction in ACTH-induced steroid secretion. Under the conditions used in these experiments, viable numbers of cell and of total amount of protein per dish were not measurably changed, indicating that the condition was not lethal. Another antimitotic drug, colcemid, caused similar reactions, while lumicolchicine showed no effect. This suggests that the disruption of the microtubular system is the main cause of the inhibition. On the other hand, the ACTH-independent secretion was slightly enhanced by colchicine. The enhancement was also observed in prolonged incubation with colchicine, a condition which caused death in some of the cells.

Adrenal Cortex Neoplasms↗
PubMed1988

S-100 beta positive T cell leukemia.

We reported a peculiar case with T cell leukemia. The patient was a 34-year-old woman showing extensive splenomegaly and marked leukemic cell proliferation and running a rapid fatal clinical course. The leukemic cells were morphologically ordinary lymphocytes showing suppressor/cytotoxic(s/c) T cell phenotypes and containing S-100b protein. Southern blot analysis revealed rearrangement of the beta chain genes of the T cell receptor (TcR) of the leukemic cells. Because these phenotypic and morphologic features were identical with those of S-100 beta+T lymphocytes (S-100 beta +TL) in normal human peripheral blood, we regarded this case as S-100 beta +T cell leukemia. We discussed clinicopathological features of S-100 beta +T cell leukemia/lymphoma by assessing similar cases reported so far. S-100 beta +T cell leukemia/lymphoma is a new type of s/c T lymphocytic leukemia/lymphoma with aggressive features.

Adult↗
PubMed1987

Induction of delayed-type hypersensitivity by the T cell line specific to bacterial peptidoglycans.

A T cell line specific for the chemically well-defined peptidoglycan of bacterial cell wall, disaccharide tetrapeptide, was established from Lewis rats immunized with the antigen covalently linked to the autologous rat serum albumin. The antigen specificity was examined with various analogues or derivatives of the peptidoglycan. The cell line was reactive to analogues with the COOH-terminal D-amino acid, but least reactive to those with L-amino acid as COOH terminus. Transferring of the T cell line into X-irradiated normal Lewis rats induced delayed-type hypersensitivity in an antigen specific manner.

Animals↗
PubMed1987

Limited chymotryptic digestion of bovine adrenal 190,000-Mr microtubule-associated protein and preparation of a 27,000-Mr fragment which stimulates microtubule assembly.

A heat stable microtubule-associated protein of Mr 190,000 (190-kDa MAP) has been purified from bovine adrenal cortex (Murofushi, H., Kotani, S., Aizawa, H., Hisanaga, S., Hirokawa, N., and Sakai, H. (1986) J. Cell Biol. 103, 1911-1919). Limited chymotryptic digestion of 190-kDa MAP produced a fragment of Mr 27,000 (27-kDa fragment), which bound to microtubules reconstituted in the presence of taxol. This fragment was purified with the aid of cosedimentation with microtubules. The purified 27-kDa fragment showed an ability to stimulate tubulin polymerization in the absence of taxol. Electron microscopic observation of microtubules reconstituted from purified 27-kDa fragment and tubulin revealed that the microtubules were in the form of thick bundles and that lateral projections which can be seen in microtubules reconstituted from intact 190-kDa MAP and tubulin were not observed. These results indicate that 27-kDa fragment includes or is a part of microtubule-binding domain of 190-kDa MAP and that this fragment is active in stimulating microtubule assembly. Amino acid analysis revealed that the 27-kDa fragment was rich in lysine, proline, and alanine, the sum of these three being about 45% of the total amino acids and that the contents of methionine, tyrosine, phenylalanine, and histidine were very low. These data suggest that the microtubule binding domain of the 190-kDa MAP comprises an unique structure.

Adrenal Cortex↗
PubMed1987

Comparison of a major heat-stable microtubule-associated protein in HeLa cells and 190-kDa microtubule-associated protein in bovine adrenal cortex.

A heat-stable microtubule-associated protein (MAP) with a molecular weight of 190,000, termed 190-kDa MAP, has been purified from bovine adrenal cortex (Murofushi, H. et al. (1986) J. Cell Biol. 103, 1911-1919). Immunoblotting experiments using an antibody against this MAP revealed that several kinds of culture cells derived from human tissues contain proteins with an apparent molecular weight of 180,000 reacting with the antibody. Indirect immunofluorescence microscopic observation of HeLa cells showed that the immunoreactive protein co-exists with microtubules, indicating that the protein is one of the HeLa MAPs. A heat-stable MAP with a molecular weight of 180,000, termed here HeLa 180-kDa MAP, was purified by the taxol-dependent procedure (Vallee, R.B. (1982) J. Cell Biol. 92, 435-442) and successive co-polymerization with brain tubulin. This protein was the most abundant MAP in HeLa cells, suggesting that the MAP is identical to the major HeLa MAP previously reported by Bulinski and Borisy (Bulinski, J.C. & Borisy, G.G. (1980) J. Biol. Chem. 255, 11570-11576) and Weatherbee et al. [1980) Biochemistry 19, 4116-4123). It was shown that, like bovine adrenal 190-kDa MAP, yet distinct from brain MAP2 and tau, purified HeLa 180-kDa MAP does not interact with actin filaments. This common characteristic of the two MAPs along with the same heat-stability strongly suggests that they are members of the same group of MAPs. The fact that HeLa 180-kDa MAP reacts with an antibody against bovine adrenal 190-kDa MAP means that they share common epitopes, in other words, common local amino acid sequences. However, the limited proteolytic patterns of the two MAPs with S. aureus V8 protease and chymotrypsin were distinct from each other, suggesting the presence of large differences in the overall primary structures between bovine adrenal 190-kDa MAP and HeLa 180-kDa MAP.

Actins↗
PubMed1987

Chemical composition and immunobiological activities of sodium dodecyl sulphate extracts from the cell envelopes of Actinobacillus actinomycetemcomitans, Bacteroides gingivalis and Fusobacterium nucleatum.

The chemical composition and immunobiological activities in vivo and in vitro of sodium dodecyl sulphate extracts (SDS-SE) derived from periodontopathic bacteria (three strains of Actinobacillus actinomycetemcomitans, two strains of Bacteroides gingivalis, and one strain of Fusobacterium nucleatum) were investigated. The main components of SDS-SE were protein and lipid, with negligible amounts of peptidoglycan and lipopolysaccharide. Immunopotentiating activity was detected in both delayed-type hypersensitivity and antibody formation against the elicitation of a protein antigen with the SDS-SE preparations of A. actinomycetemcomitans ATCC 29524 and B. gingivalis 381 and 1021. On the other hand the SDS-SE of A. actinomycetemcomitans ATCC 29522 enhanced only the induction of a delayed-type hypersensitivity response. All the SDS-SE preparations had mitogenic activity to splenocytes from BALB/c nu/nu, C3H/HeN and C3H/HeJ mice. Migration-stimulating activity for human peripheral blood monocytes was detected especially in the SDS-SE preparations of A. actinomycetemcomitans ATCC 29524 and Y4. All of the SDS-SE samples inhibited [3H]thymidine uptake in human gingival fibroblasts and caused degradation of the cells. The results suggest that the cell membrane components extractable with sodium dodecyl sulphate from periodontopathic bacteria are involved in the pathogenesis of periodontal disease.

Actinobacillus↗
PubMed1987

Possible existence of a novel amphipathic immunostimulator in the phenol-water extracts of Mycobacteriaceae.

The extracts having diverse immunostimulating activities were obtained as a water-phase fraction from four bacterial species representing the 4 genera (Mycobacterium, Nocardia, Gordona, and Rhodococcus) of Mycobacteriaceae by the phenol-water method, which is commonly used for extraction of endotoxic lipopolysaccharides (LPS) from gram-negative bacteria and amphipathic substances from gram-positives. These fractions, especially those of G. aurantiaca and R. terrae, showed strong stimulatory effects on murine splenocytes, macrophages of mice and guinea pigs, the immunoadjuvant activities in guinea pigs and mice, and the distinct activities inducing a tumor necrosis factor and interferons alpha/beta and gamma in primed mice. The fractions from G. aurantiaca and R. terrae exhibited potent pyrogenicity and the ability to activate the clotting enzyme cascade of the horseshoe crab (Tachypleus tridentatus). Some of these biological activities were not very different from the potency of the reference endotoxic LPS derived from Escherichia coli or Fusobacterium nucleatum. But the test fractions neither showed the activity to prepare rabbit skin to the local Shwartzman reaction, nor reacted with anti-lipid A conventional and monoclonal antibodies. Furthermore, unlike LPS, these fractions stimulated the splenocytes of C3H/HeJ mice (LPS-Nonresponder). Although the fractions showing the above biological activities have not yet been adequately purified, they contained polysaccharides, whose main constituent sugar is mannose with a smaller amount of arabinose, fatty acids consisting primarily of palmitic, stearic, and tuberculostearic acids, and small amounts of peptides and amino sugars. Since components characteristic of known immunomodulators of bacterial origin, namely endotoxins (lipid A's), cell wall peptidoglycans, lipoteichoic acids, cord factors (trehalose dimycolates), or deoxyribonucleic acids, were practically not detected in these fractions, the agent responsible for the above bioactivities is considered to be a novel substance different from the known, bacterial immunomodulators.

Adjuvants, Immunologic↗
PubMed1987

Activation of the human complement cascade by bacterial cell walls, peptidoglycans, water-soluble peptidoglycan components, and synthetic muramylpeptides--studies on active components and structural requirements.

Cell walls isolated from 29 strains of 24 gram-positive bacterial species, whose peptidoglycans belong to the group A type of Schleifer and Kandler's classification, with one exception (Arthrobacter sp.), were shown to activate the complement cascade in pooled fresh human serum mainly through the alternative pathway and partly through the classical one. The complement-activating effect of cell walls (5 species) possessing group B type peptidoglycan, except those of Corynebacterium insidiosum, was weaker than that of the walls with group A type peptidoglycan. Preparations of peptidoglycan isolated from cell walls of Staphylococcus aureus, Streptococcus pyogenes, and Lactobacillus plantarum also activated the alternative pathway of the complement cascade, but less effectively than the respective parent cell walls. A water-soluble "polymer" of peptidoglycan subunits (SEPS), which was prepared from Staphylococcus epidermidis peptidoglycans by treatment with a cross-bridge degrading endopeptidase, retained most of the complement-activating ability of the parent cell walls. A peptidoglycan "monomer," SEPS-M, which was obtained by hydrolysis of the glycan chain of SEPS with endo-N-acetylmuramidase to disaccharide units did not activate complement. In conformity with this finding, neither synthetic N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) nor MDP-L-Lys-D-Ala activated the complement cascade. Among several lipophilic derivatives of MDP, 6-O-(3-hydroxy-3-docosylhexacosanoyl)-MDP-L-Lys-D-Ala (BH48-MDP-L-Lys-D-Ala) and 6-O-(2-tetradecylhexadecanoyl)-MDP (B30-MDP) were shown to activate complement through the alternative as well as the classical pathway and exclusively through the classical pathway, respectively. The finding that a D-isoasparagine analog of B30-MDP caused the same effect as the parent molecule strongly suggests that the activation of complement by B30-MDP is different from that caused by cell wall peptidoglycans and a water-soluble "polymer" of peptidoglycan subunits.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1987

Requirement of a properly acylated beta(1-6)-D-glucosamine disaccharide bisphosphate structure for efficient manifestation of full endotoxic and associated bioactivities of lipid A.

Several synthetic acylated glucosamine monophosphates, with structures corresponding to the nonreducing or reducing moiety of the lipid A of the Escherichia coli or Salmonella minnesota type, and a synthetic compound corresponding to a biosynthetic disaccharide lipid A precursor (designated Ia or IVA) were examined for their endotoxic and related bioactivities in comparison with those of the synthetic and bacterial parent molecules, i.e., acylated beta(1-6)-D-glucosamine disaccharide bisphosphates. Some of the test monosaccharide compounds were definitely active in most of the in vitro assays. Their activities, except for complement activation, however, were weaker than those of the reference compounds, synthetic and bacterial acylated disaccharide bisphosphates. The differences between the test monosaccharide and disaccharide compounds were much more apparent in in vivo assays, in which the test acylated glucosamine monophosphates were scarcely active, though some test compounds exhibited weak lethal toxicity in galactosamine-loaded mice and were weakly active in pyrogenicity, immunoadjuvant activity, and possible tumor necrosis factor and alpha and beta interferon-inducing ability in Mycobacterium bovis BCG- and Propionibacterium acnes-primed mice, respectively. Mixture at an equimolar ratio of acyl glucosamine monophosphates, each of which has the structure of the reducing or nonreducing moiety of the reference disaccharide compound, did not restore the endotoxic or associated bioactivities of the corresponding parent molecules. No essential differences in bioactivity were noted between synthetic and bacterial monosaccharide compounds, i.e., lipid X, whose structure corresponds to the reducing moiety of E. coli-type lipid A.

Acylation↗
PubMed1987

Analgesic effects of N-acetylmuramyl-L-alanyl-D-isoglutamine in decreasing the acetic acid-induced abdominal-writhing response.

A new pharmacological action of N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) is described. Pretreatment of male ddY mice with MDP, but not its biologically inactive analogs, significantly decreased the frequency of acetic acid-induced writhing movements more effectively than did acetylsalicylic acid (aspirin). The analgesic effect of MDP, however, was less than that of a narcotic antagonist, pentazocine.

Acetates↗
PubMed1987

Identification of the 190 kD microtubule-associated protein in cultured fibroblasts and its association with interphase and mitotic microtubules.

We previously investigated the biochemical characteristics of microtubule-associated proteins (MAPs) of the adrenal medulla and adrenal cortex and found that they contain a new kind of MAP with a molecular weight of 190,000 (190 kD MAP) as a major species (Kotani, S., H. Murofushi, S. Maekawa, C. Sato, and H. Sakai. Eur. J. Biochem. 156, 23-29, 1986). We now have used an affinity purified anti-(190 kD MAP) antibody and show by indirect immunofluorescent microscopy the association of this MAP with microtubules in situ in TIG-3 cells (human embryonic lung fibroblasts). The 190 kD MAP was present along the interphase and mitotic microtubules, and there was no marked difference between the staining pattern with anti-tubulin and that with anti-(190 kD MAP) antibodies, evidence that the localization of 190 kD MAP is not restricted to the subset of microtubules. We also isolated MAPs from TIG-3 cells and identified their 190 kD MAP as a major heat-stable component. Several other unidentified polypeptides were recovered in the MAP fraction specifically.

Fibroblasts↗