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Biomedical subjects

H Takada

Publications and source records attributed to H Takada.

At least 325 records · Page 18Linked to original sources
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

Enhancement of endotoxin lethality and generation of anaphylactoid reactions by lipopolysaccharides in muramyl-dipeptide-treated mice.

Intravenous injection of muramyl dipeptide (MDP) and Salmonella lipopolysaccharides (LPS) enhanced lethal toxicity of the LPS in C57BL/6 mice. This was true for S (smooth)- and R (rough)-form LPS and free lipid A. Enhancement of toxicity was maximum when the LPS was administered 4 h after MDP, at which time the lethal doses for 50% of mice of S- and R-form LPS and free lipid A were between 1 and 10 micrograms, compared with more than 100 micrograms in normal animals. This sensitization was absent in endotoxin-resistant C3H/HeJ mice. Lethality usually commenced 15 h after LPS injection and was complete after 72 h. Higher doses of some S-form LPS (100 micrograms or more) administered 4 h after MDP led to a strong anaphylactoid reaction within 10 to 20 min of injection, with lethal outcomes in less than 1 h after LPS administration. This early anaphylactoid reaction was observed for various mouse strains, including LPS-resistant C3H/HeJ mice, but it was very weak or completely absent with R-form LPS or free lipid A even in concentrations of up to 1,000 micrograms. A strong anaphylactoid reaction comparable to that seen with S-form LPS was also obtained, after MDP treatment, with an LPS of low toxicity prepared from Bacteroides gingivalis. It is noteworthy that oral administration of MDP also contributed to the anaphylactoid reaction and enhanced the late-phase lethality of LPS. The present findings strongly suggest that the early- and late-phase reactions induced by MDP and LPS are caused by different mechanisms.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1987

Structural requirements of muramylpeptides for induction of necrosis at sites primed with Mycobacterium tuberculosis in guinea pigs.

Intracutaneous injection of N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) in guinea pigs caused an extensive necrotic reaction in footpads prepared by injection of heat-killed Mycobacterium tuberculosis in water-in-mineral-oil emulsion. We examined a variety of analogs and derivatives of muramylpeptides for their ability to provoke this reaction. A maximum and a minimum structure responsible for the necrotic reaction were found to be N-acetylglycosaminyl-beta(1-4)-N-acetylmuramyl-tripeptide (GlcNAc-MurNAc-L-Ala-D-isoGln-meso-A2pm) and MDP, respectively. An unexpected finding was that GlcNAc-MurNAc-tetrapeptides having L-amino acids at their C termini, unlike comparable compounds having C-terminal D-amino acids, exhibited definite necrosis-inducing activity, probably due to their tendency to undergo in vivo degradation to GlcNAc-MurNAc-tripeptide. Introduction of some acyl groups, especially the stearoyl group, to the 6-O position of the muramic acid or the peptide moiety of muramylpeptides increased the necrosis-inducing activity of the parent molecules. However, this was not observed with 1-thio-muramic acid analogs of MDP. Modification of the alpha- or gamma-carboxyl groups of the glutamic acid residues of muramylpeptides tended to decrease their necrosis-inducing ability. Analogs and derivatives of muramylpeptides which are capable of inducing necrosis at a primed site, with few exceptions, exhibited powerful adjuvanticity against ovalbumin in guinea pigs. However, the reverse was not necessarily true.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1987

Isolation and characterization of an amphipathic antigen from Corynebacterium diphtheriae.

Amphipathic antigen was isolated from Corynebacterium diphtheriae Park-Williams number 8 cells by extraction with 47.5% phenol, nuclease treatment and gel filtration on Sepharose 6B. The chemical composition of the amphipathic antigen was hexose (73.8%), pentose (4.6%), fatty acids (9.8%) and glycerol (4.5%). The amphipathic antigen contained arabinose and mannose as sugars at a molar ratio of 1:6 and the major fatty acids were palmitic (C16:0) acid and palmitoleic (C16:1) acid (64.2% and 26.2%, respectively). The amphipathic antigen sensitized sheep erythrocytes and had definite immunobiological activities: viz mitogenic activity on murine splenocytes, stimulatory activity on guinea pig peritoneal macrophages and human complement activation. Deacylation of the amphipathic antigen with alkali treatment lost the sheep erythrocyte-sensitizing ability and some immunobiological activities. The isolated amphipathic antigen described is not a lipoteichoic acid and is different from the teichoic acid of C. diphtheriae.

Amino Acids↗
PubMed1987

[Combination chemotherapy of cyclophosphamide, adriamycin and cisplatin in advanced urothelial cancer].

Sixteen patients with advanced evaluable urothelial cancer were treated with a chemotherapy regimen of cyclophosphamide, adriamycin and cisplatin (CAP). Cisplatin 50 mg/m2 and adriamycin 30 mg/m2 were given on the first day and cyclophosphamide 200 mg/m2 was given from the second to the fifth day. This course was repeated every 3 weeks. The objective response rate was 25% (4 of 16 patients), with 1 patient achieving complete remission. The survival time of responders was longer than that of nonresponders, although the difference was not significant (generalized Wilcoxon method). As side effects, nausea with vomiting (43.8%), renal dysfunction (6.3%), anemia (12.5%), leucopenia (12.5%), thrombocytopenia (25.0%), alopecia (68.8%), heart failure (6.3%) and peripheral neuropathy (6.3%) were noticed. One patient died of sepsis due to agranulocytosis and another died suddenly of heart failure.

Adult↗
PubMed1986

Synthetic Salmonella-type lipid A antigen with high serological specificity.

A synthetic compound (compound 516), beta(1-6)-linked D-glucosamine disaccharide 1,4'-bisphosphate, which is acylated by (R)-3-hexadecanoyloxytetradecanoyl, (R)-3-hydroxytetradecanoyl, (R)-3-dodecanoyloxytetradecanoyl, and (R)-3-tetradecanoyloxytetradecanoyl groups at positions 2,3,2', and 3', respectively, exhibited in vitro antigenic reactivity of high specificity comparable to that of free lipid A from Salmonella minnesota R595. This was confirmed by an enzyme-linked immunosorbent assay and an enzyme-linked immunosorbent assay inhibition test with monoclonal and conventional antibodies. The results of comparative analysis performed with several synthetic lipid A analogs as well as three monosaccharide derivatives suggested that the complete structure involving both phosphate groups at the C-1 and C-4' positions and the 3-acyloxyacyl groups at the C-2, C-2', and C-3' positions of the glucosamine disaccharide are required for the expression of the serological specificity of Salmonella-type lipid A. This was deduced from the observations that compound 506, a synthetic Escherichia coli-type lipid A which has the same structure as that of compound 516, except that 3-hydroxytetradecanoyl group is substituted for an acyloxyacyl residue at the C-2 position, exhibited significantly reduced antigenic reactivity as compared with compound 516 and that the replacement by the hydrogen atom of the phosphoryl group at the C-1 position or by 3-hydroxytetradecanoyl or tetradecanoyl groups of acyl residues at the 2, 3, 2', and 3' positions of compound 516 results in a marked reduction of reactivity with monoclonal antibodies 5G and 36G. Similar results were obtained by assays with conventional rabbit antibodies, but the structural difference between compounds 516 and 506 could not be distinguished by these polyclonal antibodies. The results of cross-reactions among synthetic analogs with monoclonal antibodies 161M and 1-9M, which have been confirmed to exhibit different serological specificities from the 5G or 36G antibody, also suggested that the nature and linkage of fatty acyl residues as well as the backbone structure of lipid A play an important role in determining serological specificity of the lipid A molecule.

Antigens, Bacterial↗
PubMed1986

Low endotoxic activities of synthetic Salmonella-type lipid A with an additional acyloxyacyl group on the 2-amino group of beta (1-6) glucosamine disaccharide 1,4'-bisphosphate.

A synthetic lipid A (Salmonella type, compound 516), beta (1-6)-linked D-glucosamine disaccharide 1,4'-bisphosphate, with three acyloxyacyl groups and one hydroxyacyl group, i.e., (R)-3-hexadecanoyloxytetradecanoyl, (R)-3-hydroxytetradecanoyl, (R)-3-dodecanoyloxytetradecanoyl, and (R)-3-tetradecanoyloxytetradecanoyl groups at the 2-amino, 3-hydroxyl, 2'-amino, and 3'-hydroxyl groups, respectively, was less biologically active than the synthetic Escherichia coli-type lipid A (compound 506), which has only two acyloxyacyl groups at the 2' and 3' positions and is substituted with a (R)-3-hydroxytetradecanoyl group at the 2-amino group. Compound 516 exhibited considerably weaker pyrogenic and leukopenic activity than compound 506, and it scarcely prepared rabbit skin for the Shwartzman reaction and lacked lethal toxicity on chicken embryos, although its lethal toxicity in galactosamine-loaded mice was as strong as that of compound 506. Compound 516 was also less active than compound 506 or natural E. coli lipid A (from Restrain F515) in other biological test systems, such as the Limulus test, stimulation of macrophages and lymphocytes, and interferon-inducing activity but not for interleukin-1 induction or complement activation. This observation suggests that there is an optimal number of acyloxyacyl groups on the glucosamine backbone for producing the biological activities of lipid A, especially the endotoxic activities. The 4'-monophosphate analog (compound 514) of compound 516 in general had significantly weaker activity than compound 516 in the above assays, most probably because of its greater hydrophobicity and consequently lower solubility in assay systems. Bacterial R595 lipid A derived from S. minnesota Re-mutant, which is a mixture of compounds 516 and 506, their 4'-monophosphate analogs and other compounds, exerted intermediate degrees of activity between compounds 506 and 516 in the various test systems employed.

Adjuvants, Immunologic↗
PubMed1986

Immunobiological activities of synthetic lipid A analogs with low endotoxicity.

Synthetic lipid A analogs, beta(1-6)glucosamine disaccharide 1,4'-bisphosphates, which possesses four tetradecanoyl groups at the 2- and 2'-amino, and 3- and 3'-hydroxyl groups (LA-17-PP), and each two of the (R)-3-hydroxytetradecanoyl and tetradecanoyl groups at the 2- and 2'-amino and 3- and 3'-hydroxyl groups, respectively (LA-18-PP), were far less endotoxic than synthetic (506, LA-15-PP) and bacterial Escherichia coli type lipid A's; neither compound showed any detectable lethal toxicity in chicken embryos or preparatory activity for the local Shwartzman reaction in rabbits. Also both compounds were only weakly pyrogenic and comparably less lethally toxic in galactosamine-loaded mice than the reference synthetic and bacterial lipid A's and a synthetic counterpart to biosynthetic lipid A precursor Ia (406, LA-14-PP). Nevertheless, LA-17-PP and LA-18-PP exhibited definite in vivo immunoadjuvant activity in mice, and the ability to induce a possible tumor necrosis factor and alpha/beta interferon in Mycobacterium bovis BCG and Propionibacterium acnes-primed mice, respectively, although these activities were weaker than those of the reference lipid A's. 4'-Monophosphate analogs of the above two test compounds exhibited neither endotoxic nor beneficial activities, but they showed remarkable in vitro bioactivities comparable to those of the corresponding bisphosphate compounds; the ability to activate the human complement system and the clotting enzyme cascade of horseshoe crab amoebocyte lysate, stimulatory effects on guinea pig and murine peritoneal macrophages, and murine splenocytes.

Adjuvants, Immunologic↗