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G Soma

Publications and source records attributed to G Soma.

At least 37 records · Page 2Linked to original sources
PubMed1993

Gangliosides can activate human alternative complement pathway.

The alternative complement pathway (ACP) in vertebrates is known to be important in inflammatory reactions, and to be activated by foreign substances such as bacterial lipopolysaccharide (LPS) and zymosan, although to date no intrinsic activators have been identified except complement receptor type 2. From the point of the structural similarity of LPS to ganglioside, we have investigated gangliosides which are abundantly present in animal cells for their activity on the human ACP. All of seven gangliosides tested were found to activate this pathway in a manner depending on the number of sialic acids and neutral sugars contained in the molecules. A dose-response study suggested a correlation of the threshold in ganglioside concentration with its critical micelle concentration. Gangliosides may thus serve as an intrinsic activator for ACP in animals, thereby leading to inflammation. The possibility of the participation of sialidase in complement activation is also discussed.

Complement Pathway, Alternative↗
PubMed1992

Expression of transcripts of complement components and their receptors during differentiation of embryonal carcinoma cell lines.

Based on our previous finding that TNF-alpha and TNF-beta can be expressed constitutively during early embryonal development [1], we extended our work to identify factors which are generally known to take part in inducing inflammation in adults. They can be regarded as candidate molecules involved in ontogenic inflammation during embryonal development. In this study, we chose the factors which are constituents of either a classical or an alternative pathway of a complement system and found that mRNAs corresponding to those of C2, C3, C4, C5 and to those of receptors CR1 and CR2 were expressed. Among them, mRNA expression of C3, C4, and CR1 was especially constitutive. Contrary to these observations, expression of two kinds of scavenger receptors (SR-I, SR-II) proved to be negative. In this report, the framework of ontogenic inflammation as a regulatory mechanism in embryonal development at the molecular level is discussed.

Animals↗
PubMed1992

Homeostasis as regulated by activated macrophage. VI. Protective effect of LPSw (a lipopolysaccharide from wheat flour) against acute infection by Toxoplasma gondii in mice.

An oral administration of partially purified LPSw, a lipopolysaccharide (LPS) from wheat flour, at a concentration of 20 ng/ml in drinking water beginning 1d after infection significantly decreased mouse mortality and prevented animal weight loss in acute infection with Toxoplasma gondii. Whereas 71% (5/7) of mice in a control group that did not receive LPSw died of toxoplasmosis, only 14% (1/7) of mice treated with LPSw died (p less than 0.05). The administration of LPS purified from Bordetella pertussis also significantly decreased the mortality of infected mice. LPS from Escherichia coli and synthetic lipid A (LA-15-PP(506)), however, did not show a significant decrease in mortality.

Acute Disease↗
PubMed1992

Homeostasis as regulated by activated macrophage. VII. Suppression of serum cholesterol level by LPSw (a lipopolysaccharide from wheat flour) in WHHL (Watanabe heritable hyperlipidemic) rabbit.

The effect of LPSw (a lipopolysaccharide from wheat flour) on cholesterol catabolism was examined using WHHL (Watanabe heritable hyperlipidemic) rabbit, which is an experimental model of familial hyperlipidemia. The serum cholesterol level of the animal decreased by the addition of LPSw to drinking water. Following cessation of the addition of LPSw to the drinking water, the cholesterol level was decreased for 30 to 40d and then gradually elevated. The serum level of apolipoprotein B, which is a constituent of apolipoprotein of low density lipoprotein (LDL), also decreased in accord with serum cholesterol at a nearly coincident rate. Conversely, the level of apolipoprotein A-I, which is a constituent of apolipoprotein of high density lipoprotein (HDL), did not change, nor did HDL-cholesterol. Furthermore, the atherosclerosis risk factor, expressed as the ratio of apolipoprotein B to apolipoprotein A-I, was decreased by LPSw administration.

Animals↗
PubMed1992

Homeostasis as regulated by activated macrophage. VIII. LPSw (a lipopolysaccharide from wheat flour) can regulate bone resorption of chick embryo.

The effect of LPSw (a lipopolysaccharide from wheat flour) on the bone resorption of 18-d chick embryonic calvaria was examined in an organ culture following the method of Raisz. Bone was prelabeled in culture medium containing 45Ca and chased in a cold medium. On addition of test samples, labeled calcium was released indicating the grade of bone resorption. LPSw (10-100 ng/ml) stimulated bone resorption, showing an effect comparable to parathyroid hormone (PTH) (1 U/ml). PTH at 1 U/ml decreased the total amount of calcium and phosphorus, while LPSw did not. LPSw is thus assumed to stimulate bone resorption more actively than PTH.

Animals↗
PubMed1992

Homeostasis as regulated by activated macrophage. IX. Enhancement effect of LPSw (a lipopolysaccharide from wheat flour) on hen egg-laying and breaking strength of eggshell.

Oral administration of LPSw (a lipopolysaccharide from wheat flour) given at 60 micrograms/hen/d in drinking water, markedly enhanced eggshell strength. The monthly percentage of eggs laid with a shell strength of more than 4 kg to the total number of eggs was 32% in the group given LPSw in drinking water while it was 12% in the control group given plain water. At the same time, LPSw caused a 30% enhancement of total monthly number of eggs laid over that of control.

Animals↗
PubMed1992

Homeostasis as regulated by activated macrophage. I. Lipopolysaccharide (LPS) from wheat flour: isolation, purification and some biological activities.

Based on our new concept of ontogenic inflammation, we have sought a substance which can prime macrophage in terms of the endogenous production of tumor necrosis factor (TNF). A lipopolysaccharide (LPSw) was found in wheat flour, purified and characterized. The molecular size of LPSw was about 5 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and it contained 3-deoxy-D-manno-octulosonic acid: 1, hexosamine: 4 and one phosphorus in a single molecule. LPSw can prime macrophage to release TNF when given intradermally, percutaneously or even orally in mice as well as in humans, in exactly the same way as intravenous administration of interferon gamma.

Administration, Oral↗
PubMed1992

Oral or percutaneous administration of lipopolysaccharide of small molecular size may cure various intractable diseases: a new version of Coley's toxin.

Based on our new finding that an inflammation in which tumor necrosis factor (TNF) is primed or triggered (ontogenic inflammation) can regulate the homeostasis in ontogenesis, we have identified a new lipopolysaccharide from wheat flour (LPSw) that can induce ontogenic inflammation in adult mice. LPSw can prime adult mice to produce TNF when given orally or percutaneously, suggesting that it may maintain homeostasis in adults. LPSw can cure experimental animals of diabetes, hyperlipidemia, ulcer, and herpes. It can also stimulate bone resorption and egg-laying, and shows a strong analgesic effect that is blocked by naloxone. This effect even allows a release from drug addiction. Suppression of serum cholesterol level by oral uptake of LPSw in Watanabe heritable hyperlipidemic (WHHL) rabbit was also observed. Infection of toxoplasma was prevented by oral uptake of LPSw. The realization that a single oral or percutaneous administration of LPSw may be a cure for multiple intractable diseases may lead to the presentation of a nontoxic type of Coley's toxin, which is known to be an efficient cancer treatment, but has high toxicity.

Administration, Cutaneous↗
PubMed1991

Purification of recombinant human tumor necrosis factor precursor from Escherichia coli.

To study its biological functions, tumor necrosis factor precursor (proTNF) with a molecular size of 26-KDa was obtained as a recombinant protein from Escherichia coli. The recombinant proTNF was successfully accumulated in the insoluble form, corresponding to about 10-15% of total E. coli proteins. Solubilization, gel filtration and anion exchange chromatography were performed under denatured conditions followed by dialysis in phosphate-buffered saline. These processes removed most of the contaminating bacterial proteins, yielding proTNF with a purity of about 70-80%. This recombinant proTNF is expected to be useful for functional studies on activated macrophages with membrane integrated proTNF.

Blotting, Western↗
PubMed1991

Antitumor activity of a novel chimera tumor necrosis factor (TNF-STH) constructed by connecting rTNF-S with thymosin beta 4 against murine syngeneic tumors.

We have shown the in vivo usefulness of a novel chimera tumor necrosis factor (TNF), called rTNF-STH, which was constituted with human thymosin beta 4 and recombinant human TNF-SAM1. Tumor necrosis was induced by intravenous injection of a smaller amount of rTNF-STH (1 x 10(3) U/mouse, 0.67 microgram/mouse) than rTNF-alpha or rTNF-S (1 x 10(4) U/mouse, 2.5-5 micrograms/mouse). Significant antitumor effects of rTNF-STH to Meth A fibrosarcoma, B16 melanoma, MH134 hepatoma, or Lewis lung carcinoma (3LL) were observed by systemic injection of rTNF-STH at the maximum tolerable dose of 1 x 10(4) U/mouse (6.7 micrograms/mouse); this dose did not cause regression of tumors by conventional rTNF-alpha. rTNF-STH showed a significant prolongation of its half-life in serum. The average calculated half-life of the chimera protein is about 110 min, which is 15 times longer than that of original TNF-SAM1 (7.5 min). On the basis of this prolongation of half-life of rTNF-STH and its efficient hemorrhagic necrotic activity, the antitumor effect of rTNF-STH--as compared with that of the known TNF species--is discussed. Findings indicate that use of the chimera protein to alter the N-terminal region of TNF may be a promising approach to obtain molecules that more favorably attack tumors and other diseases than conventional rTNFs.

Animals↗
PubMed1991

Post-translational processing of tumor necrosis factor production.

To elucidate the mechanism of tumor necrosis factor (TNF) production, we analyzed proteins produced in macrophages sharing the epitope of TNF according to the priming and triggering of TNF production. Rabbit alveolar macrophages primed with Bacillus Calmette-Guerin (BCG) were isolated and cultured in vitro with 35S-methionine, and the proteins produced were analyzed using anti-rabbit TNF monoclonal antibody. Primed with BCG, alveolar macrophages synthesized two proteins with molecular sizes of 50 and 17 kilodaltons (kDa) (p50 and p17) sharing the same epitope with mature TNF within the cells. These two proteins were released into the medium where other proteins were detected without TNF-activity. Cultured with lipopolysaccharide (LPS triggering), the primed alveolar macrophages released TNF-activity into the medium where p17 together with many larger proteins was detected by immunoprecipitation. In vitro translation of messenger ribonucleic acid (mRNA) from BCG-primed macrophages showed that primary TNF has a molecular size of 28 kDa (p28). These results suggest that active TNF of p17 is secreted when triggered via post-translational processing of the precursor molecules synthesized through priming with BCG.

Animals↗
PubMed1991

Intratumoral tumor necrosis factor induction in tumor-bearing mice by exogenous/endogenous tumor necrosis factor therapy as compared with systemic administration of various biologic response modifiers.

The relationship between the induction of tumor necrosis factor (TNF) (as an indicator of inflammatory reaction) in tumor tissues and its antitumor effect was investigated in tumor-bearing mice by using nine biologic response modifiers (BRMs) and by exogenous/endogenous TNF therapy following a previously reported protocol. Close correlation between the induction of TNF-rich inflammation in tumor tissues and the antitumor effect of BRM were observed. The results of this study suggest that the conditions necessary for exerting antitumor effects of biologic response modifiers may be the induction of TNF (50 to 200 U/g) at the tumor lesions at an early stage after BRM administration and maintenance of the detectable amount of TNF (approximately 10 U/g) for more than 6 hours. Tumor necrosis factor should also be induced in the liver and spleen so that its activity can be maintained in the tumor lesions.

Animals↗
PubMed1991

Expression of TNF-alpha and TNF-beta transcripts in murine embryonal carcinoma cells and trophoblast cell.

Using a combination system of Transcription and PCR, we examined gene expression of TNF-alpha, TNF-beta and other cytokines (IL-1, G-CSF, IL-3 and IFN-gamma) in embryonal carcinoma cell lines (PCC3, PCC4, ECA2 and F9) and trophoblast cell line (PL/B6). We found that both TNF-alpha and TNF-beta transcripts were expressed in all of the embryonic cell lines. We also detected transcripts of two types of TNF receptors and transcription factor NF-kappa B in these embryonic cells.

Animals↗
PubMed1990

Transforming growth factor-beta 1 modulates the effect of 1 alpha, 25-dihydroxyvitamin D3 on leukemic cells.

The human leukemic cells HL-60, U937, KG-1 and THP-1 incubated with transforming growth factor-beta 1 (TGF-beta 1) were studied by examining cell surface antigens and macrophage-specific activities. The addition of 0.5 ng/ml (20 pM) of TGF-beta 1 with 1 alpha, 25-dihydroxyvitamin D3 [1 alpha, 25(OH)2D3] induced more Leu-M3 (CD14)-positive cells (approximately 80%) than 5 X 10(-8) M 1 alpha, 25(OH)2D3 alone did (30 to 50%), although original HL-60 cells did not express any Leu-M3 antigen at all. Tumor necrosis factor-alpha (TNF-alpha) with TGF-beta 1 and 1 alpha, 25(OH)2D3 was found to potentiate the expression of these surface antigens. Furthermore, the phagocytic activity was also induced strongly. The expression of CR3 (CD11b) antigen was also increased, and all Leu-M3-positive cells were found CR3-positive when HL-60, U937, and THP-1 cells were treated with these stimulants. In contrast, CR3 but not Leu-M3 was induced in KG-1 cells after the same treatment. This may indicate that the responsiveness of leukemic cells to TGF-beta 1 and 1 alpha, 25(OH)2D3 might vary depending on a differentiation stage of the target cells. Furthermore, K562 cells originated from a more undifferentiated precursor, were not able to respond to these two inducers. These results suggested that some of TGF-beta superfamily proteins might represent potent modulators in hematopoiesis, especially in the development of monocytes-macrophages or their precursors.

Antigens, Surface↗
PubMed1990

Priming effect of orally administered muramyl dipeptide on induction of endogenous tumor necrosis factor.

Orally administered muramyl dipeptide (MDP) was found to prime induction of endogenous tumor necrosis factor (TNF) in mice. This priming effect was observed after oral administration of MDP of more than 100 micrograms/mouse; the maximal time interval between oral administration of MDP and i.v. injection of OK-432, a triggering agent for induction of endogenous TNF, was extended over 3-10 h and then decreased after 24 h. Antitumor effect against Meth-A, MH134, and MM46 tumor cells in mice was observed after oral administration of MDP followed by i.v. injection of OK-432. These findings suggest that orally administered MDP can be used as a priming agent for inducing endogenous TNF in cancer patients, and that MDP, a component of enteric bacteria, must have an important role in maintaining homeostasis through activation of macrophages.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1989

Production and purification of a recombinant human 14 kDa beta-galactoside-binding lectin.

The cDNA for a 14 kDa human beta-galactoside-binding lectin was inserted into a plasmid carrying a taq promoter, and the lectin protein was expressed in E. coli cells. The recombinant lectin was extracted from the cells and purified to apparent homogeneity by a single-step chromatography on an asialofetuin-agarose column. Subunit molecular mass (14 kDa), hemagglutinating activity and antigenicity were indistinguishable from those of the human placental lectin. Though the N-terminal of the placental lectin is blocked with an acetyl group, the recombinant lectin was found to have a free amino group. However, the N-terminal amino acid sequences were identical. The recombinant lectin was considered to have the same three-dimensional structure as the placental lectin.

Amino Acid Sequence↗
PubMed1989

Cloning and nucleotide sequence of a full-length cDNA for human 14 kDa beta-galactoside-binding lectin.

A full-length cDNA for a 14K-type human lung beta-galactoside-binding lectin was cloned. The cDNA includes a 405 bp open reading frame coding 135 amino acids including the initiator methionine, and having a single internal EcoRI site and a polyadenylation signal. The deduced amino-acid sequence agreed completely with the sequence of a human placenta lectin determined by direct amino-acid sequence analysis (Hirabayashi, J. and Kasai, K. (1988) J. Biochem. 104, 1-4). It showed extensive sequence similarity with other vertebrate 14K-type lectins and a 35K-type lectin (carbohydrate-binding protein 35) of mouse 3T3 cell. Search of a Genbank sequence data base revealed significant sequence similarity between the beta-galactoside-binding lectins and the carboxyl-terminal half of an IgE-binding protein, the cDNA of which has been cloned from rat basophilic leukemia cells. Thus, 14K-type lectin, 35K-type lectin and IgE-binding protein appeared to form a superfamily of proteins. Almost all invariant residues are located in the central region of the 14K-type lectins, so this region may constitute an essential part of the lectins, such as the sugar-binding domain.

Amino Acid Sequence↗