Kazuyoshi Nagaki

Reaction Mechanisms of β1H Globulin

The reaction mechanisms of β 1H were studied. The generation of alternative pathway C3 and C5 convertases on the cell surface as well as in the fluid phase was inhibited by

A new method for the preparation of EAC14 cell with human or guinea-pig serum

Abstract By reacting EA with serum in the presence of triethylenetetramine-N,N,N′,N″,N‴,N‴-hexa-acetic acid (TTHA), active and stable cellular intermediate of immune hemolysis, EAC14, was successfully prepared. This method does not require isolated components of complement and is applicable to prepare EAC14hu.

Inactivator of the First Component of Human Complement (CĪINA)

Acidic mucopolysaccharides enhanced CĪINA activity against CĪs. The presence of heparin in the reaction mixture of CĪINA and CĪs markedly enhanced the inactivation of CĪs by potentiating CĪINA activit

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 Kandlers 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.

The activation mechanism of the alternative pathway of the human complement system by the immune precipitate formed with F(ab′)2 of rabbit IgG antibody: The generation of C3- and C5-cleaving enzymes of the immune precipitate

Abstract Immune precipitate (F), formed between egg albumin and the F(ab′)2 fragment of rabbit anti-egg albumin, activated the alternative pathway of the complement system in human serum. On incubation with serum, F combined with several factors in serum (X) to form a complex, FX, which was capable on inactivating purified C3 and C5. FX having maximal activity was obtained by incubation of F with serum for 10–20 min (Tmax). Tmax depended on the amount of F added to serum and a increased amound of F shortened the Tmax/ When FX was incubated at 37°C, its activities decayed as a first order reaction and were completely lost in 120 min. FX regenerated from decayed FX (FXd) by the addition of both B and D . FX also lost activity by treatment with anti-B or anti-C3. These findings indicated that F(ab′)2 activated the alternative pathway of the complement system in human serum by the formation of the properdin system enzymes on F.

Studies of four Japanese families with hereditary angioneurotic edema: Simultaneous activation of plasma protease systems and exogenous triggering stimuli

SummaryForty-five relatives of 4 families with hereditary angioneurotic edema (HANE) were studied. Twenty-five, including 11 asymptomatic kindreds with the disposition, showed typical changes in complement system compatible with HANE. Follow-up study of HANE patients showed that, even in remission period, complement, coagulation and fibrinolytic systems can be activated. During edema attacks, moderate haemoconcentration and neutrophilia were encountered and kallikrein-kinin system was found to be also activated. Replacement therapy with C

Conversion of C5 precipitin line in the serum treated with activating substances of complement system.

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Characterization of Clq Found in a Patient with Hypocomplementemic Vasculitis-Urticaria Syndrome

-inhibitor preparation for an edema attack revealed that clinical improvement paralleled the increase in blood levels of high molecular weight kininogen. Thus, HANE attack is considered to be elicited in kindreds with the hereditary disposition by activation of plasma protease systems, particularly by that of kallikrein-kinin system. On the other hand, exogenous triggers that can initiate activation of the protease systems can be classified into 2, neuro-humoral (sympathetic nerve response) and physico-chemical, categories. Hence, the edema attack of kindreds with the hereditary disposition can at least be modified by the biosynthesis of plasma factors and the individual susceptibility to the liberated catecholamines. These two different reaction processes are considered to be linked by the release of plasminogen activator and/or Hageman factor activating enzyme.