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K Yonemasu

Publications and source records attributed to K Yonemasu.

At least 55 records · Page 3Linked to original sources
PubMed1983

Subcomponents C1q of the first component of guinea pig and mouse complement. Comparative study of their asparagine-linked sugar chains.

Guinea pig and mouse C1q, subcomponents of the first component of complement, contained six asparagine-linked sugar chains on the C-terminal non-collagenous globular regions of each molecule. After N-acetylation and successive NaB3H4-reduction of asparagine-linked sugar chains liberated by hydrazinolysis, their structure was analysed by sequential exoglycosidase digestion in combination with sugar composition analyses. The sugar chains of C1q molecules of both animals were very similar and composed of the biantennary complex type sugar chains with the following outer chains in various combination is: (+/- NeuNAc alpha leads to)Gal beta 1 leads to GlcNAc beta 1 leads to and Gal beta 1 leads to Gal beta 1 leads to GlcNAc beta 1 leads to. These outer chain moieties were found to be linked to a common core structure of Man alpha 1 leads t o (Man alpha 1 leads to)Man beta 1 leads to GlcNAc beta 1 leads to (Fuc alpha 1 leads to)GlcNAc.

Animals↗
PubMed1983

Chemical studies on the isolated collagen-like and globular fragment of complement component C1q. Comparative studies on bovine and human C1q.

Both the collagen-like and the globular fragments of a subcomponent C1q of the first component of bovine and human complement were highly purified by enzymic digestion followed by gel filtration. Analyses by polyacrylamide gel electrophoresis showed that the former was composed of covalently linked peptide chains with an average molecular weight of 14 000, and that the latter was composed of three non-covalently linked peptide chains each having a molecular weight of approximately 15 000. Great similarities between amino acid compositions of the globular fragments and some similarities between those of the collagen-like fragments were found. Moreover, great similarities of amino acid compositions were found among three non-covalently linked chains of each globular fragment as well as between the corresponding chains of both globular fragments. These results suggested that both the collagen-like and the globular domains on the C1q molecule remained highly conserved in its evolution.

Amino Acids↗
PubMed1983

Antigenic interspecies cross-reaction of subcomponent C1q of the first component of complement: evidence for its cross-reaction in both collagen-like and non-collagen-like regions.

Human, bovine, and mouse C1q, a subcomponent of the first complement component, were purified, and both globular (GF) and collagen-like fragments (CLF) were isolated from human and bovine C1q. Antisera were produced in rabbits with these C1q or fragments, and F(ab')2 of immunoglobulin G (IgG) was purified from the antisera in order to avoid the possible non-specific binding of C1q of these animals to the Fc portion of rabbit IgG. Immunodiffusion analyses and radioimmune inhibition tests with these F(ab')2 showed that the definitive antigenic cross-reactivity was among C1q molecules of these animals, and that the regions participating in interspecies cross-reactions were located in both GF and CLF of C1q. These results suggest that both the C-terminal non-collagenous globular and the N-terminal collagen-like domains of C1q molecules may have remained highly conserved during evolution.

Animals↗
PubMed1983

Stimulation of locomotion of peripheral blood monocytes by human plasma fibronectin.

The motility of human peripheral blood granulocytes and monocytes in response to human plasma fibronectin was quantified by an in vitro assay using blind-well chemotaxis chambers. Purified fibronectin under nondenaturing conditions produced increased migration of granulocytes only at concentrations higher than 100 nM, and induced increased chemotactic and random locomotion of monocytes at concentrations higher than 0.1 nM. The monocyte migration-inducing activity of fibronectin was concentration dependent, and was strongly inhibited by low concentrations of colchicine (100 nM-100 microM). These findings suggest the possibility that plasma fibronectin serves as a chemotactic stimulus for monocytes in vivo and attracts these cells to sites of microscopic tissue injury where plasma fibronectin is deposited.

Chemotaxis, Leukocyte↗
PubMed1982

Structures of the asparagine-linked sugar chains of subcomponent C1q of the first component of bovine complement.

Bovine C1q, a subcomponent of the first component of complement, contains six asparagine-linked sugar chains in 1 molecule. The sugar chains are exclusively distributed in the noncollagenous regions. The sugar chains were liberated as radioactive oligosaccharides from the polypeptide portion by hydrazinolysis followed by N-acetylation and NaB[3H]4 reduction, and their structures were studied by sequential exoglycosidase digestion in combination with methylation analysis. Bovine C1q was shown to contain equal amounts of neutral and acidic oligosaccharides with the following structures: (formula, see text) where NeuG1 is N-glycolylneuraminic acid.

Animals↗
PubMed1982

The subcomponent Clq of the first component of guinea pig complement: purification and characterization.

Guinea pig C1q was purified, in a highly active hemolytic form, by a combination of precipitation with chelating agents, CM-cellulose and Sepharose 6B. Yields ranged from 30 to 35% protein, and the activity of final preparations was in the range of 2 x 10(13)--3 x 10(13) C1q effective molecules/mg. The molecular weight of C1q was approximately 430,000, as determined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS). C1q was shown to be composed of two non-covalently liked subunits of approximate molecular weights 46,500 and 45,000 in a molar ratio 2:1. One reduction, the higher molecular weight subunit gave two chains having approximate molecular weights of 24,500 and 23,000 in equimolar ration, and the lower weight subunit gave one chain with a molecular weight of approximately 22,300. C1q contained hydroxyproline, hydroxylysine and high percentage of glycine. Thus, the overall molecular structure of guinea pig C1q appears similar to that of human C1q. The antiserum against the purified C1q showed only one precipitation band with guinea pig whole serum or purified C1q on immunodiffusion analyses and was found to be monospecific.

Amino Acids↗
PubMed1981

Purification and characterization of subcomponent C1q of the first component of mouse complement.

1. Mouse C1q, a subcomponent of the first component of complement, has been purified in a highly haemolytically active form by a combination of precipitation with EGTA, ion-exchange chromatography and gel filtration. Yields ranged from 3 to 5 mg/200 ml of serum, and the activity of final preparations was in the range of 2 X 10(13)-4 X 10(13) C1q effective molecules/mg. 2. The molecular weight of mouse C1q was 439 500 +/- 1586, as determined by polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate. 3. Mouse C1q was shown to be composed of non-covalently linked subunits, all being in the molecular-weight range 45 000-46 000, and three covalently linked chains each having a molecular weight of approx. 23 000 as determined on polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate by using non-covalently and covalently linked subunits of human C1q as markers with known molecular weights calculated theoretically previously [Porter & Reid (1978) Nature (London) 275, 699-704]. 4. Mouse C1q contained hydroxyproline, hydroxylysine, a high percentage of glycine and approx. 9% carbohydrate. The absorption coefficient and nitrogen content of C1q were also determined.

Amino Acids↗
PubMed1981

Comparable content of hydroxylysine-linked glycosides in subcomponents C1q of the first component of human, bovine and mouse complement.

The hydroxylysine-glycosides in bovine and mouse C1q are directly quantified in parallel with those in human C1q after the alkaline hydrolysis of these molecules. Human, bovine and mouse C1q contain 68.3, 66.3 and 64.0 hydroxylysine-galactosylglucose residues in each of these molecules respectively. Only human C1q contains 2.5 residues of hydroxylysine-galactose per molecule, and both of bovine and mouse C1q contain no detectable hydroxylysine-monosaccharides in their molecules. The percentage of hydroxylysine residues glycosylated to total hydroxylysine residues in each of these molecules is calculated to be 86.4, 92.0 and 95.1% for human, bovine and mouse C1q respectively and is comparable with each other. The percentages of hydroxylysine residues resistant to periodate oxidation to total hydroxylysine residues in these molecules were 61.1, 65.3 and 74.3% for human, bovine and mouse C1q respectively and were significantly lower than those estimated by the direct quantification of hydroxylysine-glycosides after the alkaline hydrolysis of these molecules.

Animals↗
PubMed1980

Purification and characterization of subcomponent Clq of the first component of bovine complement.

Bovine complement subcomponent C1q was purified, in a highly hemolytically active form, by a combination of precipitation with EGTA, ion-exchange chromatography, and gel filtration. Yield ranged from 22 to 28% as protein amounts, and the activity of final preparations was in the range of 2 X 10(13)-4 X 10(13) effective molecules/mg. The molecular weight of undissociated C1q was 407,000, as determined by polyacrylamide gel electrophoresis containing sodium dodecyl sulfate (SDS). C1q was shown to be composed of two non-covalently linked subunits of approximately 46,000 and 45,000 molecular weights in a molar ratio of 2 : 1. On reduction, the higher molecular weight subunit gave two chains having approximate molecular weights of 23,600 and 22,200 in equimolar ratio, and the lower molecular weight subunit gave one chain with a molecular weight of approximately 22,000. C1q contained hydroxyproline, hydroxylysine, a high percentage of glycine and approximately 9% carbohydrate and 14.8% nitrogen. The absorption coefficient (A 1% 1cm) in 300 mM NaCl was found to be 7.3 +/- 0.12 at 280 nm. From these results, overall molecular structure of bovine C1q looks similar to that of human complement subcomponent C1q.

Amino Acids↗
PubMed1980

Immunochemical quantitation of complement components of Clq and C3 in sera and synovial fluids of patients with bone and joint diseases.

The amount of the initiating complement component (Clq) in the classical pathway and the first essential component (C3) in the alternative complement pathway were measured with a single radial immunodiffusion (SRID). A high ionic strength was used corresponding to that of 0 . 25 M NaCl and 0 . 01 M EDTA to avoid nonspecific binding of Clq with immune aggregates. Measurements were made on sera and/or synovial fluids from 165 patients with various bone and joint diseases. Values of Clq and C3 in synovial fluids were also expressed as ratios to that of albumin in the same specimens to avoid the influence of differences in volume of synovial fluid in various diseases, and this appeared to provide a reliable index reflecting pathological conditions. Both serum Clq and C3 levels were raised highly in rheumatoid arthritis, gout, and osteomyelitis, but the extent of the elevation of C3 was less conspicuous. Values of Clq and C3 in synovial fluids also markedly increased in rheumatoid arthritis.

Adolescent↗
PubMed1979

Hydroxylysine-linked glycosides of human complement subcomponent C1q and various collagens.

1. Human C1q, a subcomponent of the first component of complement, contains 67 disaccharides (glucosylgalactose) and 2.4 monosaccharides (galactose) linked to hydroxylysine in one molecule. It was found that 82.6% of the hydroxylsine residues were glycosylated. The suggestion of the possible existence of glucosylgalactosylhydroxylysine reported previously [Yonemasu, Stroud, Niedermeir & Butler (1971) Biochem. Biophys. Res. Commun. 43, 1388--1394] was confirmed. 2. The hydroxylysine-glycosides are not detected in the C-terminal, non-collagen-like, globular regions, but only in the collagen-like regions in the subcomponent C1q molecule. 3. Alpha 1(I) and alpha 2 in pig skin, alpha 1(II) in bovine cartilage and alpha 1(III) in bovine skin collagens contain 2.0, 2.2, 13.2 and 2.0 residues of hydroxylysine-glycosides per molecule, respectively. The percentage of hydroxylysine residues glycosylated in each of these chains is relatively low (on average 38%). 4. Neither the high percentage of hydroxylysine residues glycosylated nor the high values for the ratios of disaccharides to monosaccharides in the subcomponent C1q resembles that in alpha 1(I), alpha 2, alpha 1(II) and alpha 1(III). 5. Similarities between the extent of glycosylation of hydroxylysine residues in collagen-like regions in the subcomponent C1q molecule and that of the collagenous constituents of human glomerular basement membranes, aortic intima, skin A- and B-chains and of bovine anterior lens capsule are discussed.

Animals↗
PubMed1979

Immunobiological aspects of Clq in sera of patients with cutaneous vasculitis and collagen diseases.

Clq was comparatively quantified with CH50 or C3 in sera of patients with various types of cutaneous vasculitis and collagen diseases. The following results were found: 1) Elevated levels of Clq were seen much more frequently in cutaneous vasculitis and PSS. 2) No significant correlations were found between Clq and CH50 or C3, except for a moderate rank correlation between Clq and C3 in SLE. 3) The amount of hydroxyproline in serum (collagen-like protein) is nearly identical with the calculated value of that present in Clq.

Adolescent↗
PubMed1978

The asparagine-linked sugar chains of subcomponent C1q of the first component of human complement.

Human C1q, a subcomponent of the first component of complement, contains six asparagine-linked sugar chains in 1 molecule. The sugar chains are exclusively located in the COOH-terminal globular region which is composed of 330 amino acid residues. The sugar chains were liberated from the polypeptide portion by hydrazinolysis, and their structures were studied by the combination of sequential exoglycosidase digestion and methylation analysis. Based on the results, the structures NeuAcalpha2 leads to 6Galbeta1 leads to 4GlcNAcbeta1 leads to 2Manalpha1 leads to 6(+/- NeuAcalpha2 leads to 6Galbeta1 leads to 4GlcNAcbeta1 leads to 2Manalpha1 leads to 3)Manbeta1 leads to 4GlcNAcbeta1 leads to 4(+/-Fucalpha1 leads to 6)GlcNAc were confirmed.

Asparagine↗
PubMed1978

Identification and characterization of guinea-pig antibodies that contrasensitize in mice.

Immunological enhancement is a form of active immunoregulation in which humoral antibodies suppress primary sensitization or block reaction in sensitized animals. In mouse serum the antibodies that suppress sensitization in mice (allogeneic enhancement) are predominantly 7Sgamma1 and those that block reaction 7Sgamma2 globulins. But little is known about the identity of xenogeneic enhancing antibodies, e.g. guinea-pig antibodies that can suppress sensitization in mice. We have studied these here as specifically effective against induction of tuberculin-typed delayed hypersensitivity to chicken conalbumin antigen. Guinea-pigs required prolonged and intense immunization with conalbumin to produce readily measurable titres of such antibodies. Their capacity to suppress mouse sensitization was antigenically specific. Of the three major classes of antibodies separated from the immunosuppressive guinea-pig antisera, the IgG2 globulins were the most effective. These antibodies lost immunosuppressiveness if digested to either F(ab.)2 or Fab fragments that retained antigen-binding capacities. Thus, we provide here an example of xenogeneic antibody-mediated contrasensitization, show that only intact antibody molecules are effective, and demonstrate that immunosuppressiveness is concentrated in different immunoglobulin classes for xeno- and allogeneically used antisera.

Animals↗
PubMed1978

Effect of age on C1q and C3 levels in human serum and their presence in colostrum.

The initiating complement component (C1q) in the classical pathway of 730 subjects and the first essential component (C3) in the alternative pathway of 461 subjects in Japan were examined. The study population consisted of normal healthy newborns, infants, children, adults and the old (from birth up to 75 years of age). In cord sera, both C1q and C3 were about 60% to the total mean level. At 3 days of age, C1q markedly increased to the mean level which remained relatively invariable up to 40 years of age. And above 40 years, the C1q level increased steadily with age up to about 75 years of age. C3 reached the mean level at about 1 month of age, and was highest during infancy. This level declined at about puberty and then continued to increase steadily with age up to around 55 years. In normal healthy subjects, a moderate positive rank correlation was found between C1q and C3 amounts. No significant differences of C1q and C3 levels were evident between male and female. No C1q was demonstrable in the colostrum from which lipids were previously removed, but after concentration by precipitation in a chelating agent with a low ionic strength, C1q, measured immunochemically, was detectable at concentrations of 300 ng/ml of colostrum. C3 was also detected at concentrations of about 200 microgram/ml of colostrum.

Adolescent↗
PubMed1976

Development of two inbred strains of rats and characteristics of their skin reactions.

Two inbred strains of rat (Donryu and Sprague-Dawley strains) were developed. The skin reactions of these strains immunized with M. tuberculosis, hen egg albumin (OVA) or hen egg lysozyme and challenged with the purified protein derivative (PPD) or each antigen were even and uniform. The Donryu strain showed a typical Arthus reaction with petechiae and edema and a negligible delayed skin reaction, whereas the Sprague-Dawley strain showed a poor Arthus reaction and a typical delayed skin reaction with central necrosis and induration. The Arthus reaction or delayed skin reaction could be passively transferred to recipient rats of each strain by immune sera or sensitized peritoneal exudate cells (PEC), respectively.

Animals↗