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PubMed1984

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

Forty-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 1-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.

Angioedema↗
PubMed1975

Immunofluorescent investigations in cutaneous vasculitis. I. Histotopical demonstration of complement/complement factors.

Using an indirect double layer immunofluorescence method, fresh skin lesions of 10 patients with different forms of cutaneous vasculitis were tested for the occurrence of complement-factors C1q (C1), alpha2D(C3) and beta1F (C5). In contrast to the irregularly found complement fixing immunoglobulins IgG and IgM, complement could be regularly seen bound to the cutaneous vessel walls; mostly the C3-factor alpha2D. C1q was demonstrable, combined with IgG and/or IgM only in 2 cases. In 5 patients there was a non-homogenous, roddy fluorescenece of the epidermal basal membrane zone and the cutaneous vessels, when alpha2D or beta1F were tested. Our findings suggest that the "alternate pathway" beginning with C3-activation is followed in most cases, whereas a typical "immune complex vasculitis" is obviously rare. The constant occurrence of complement in the cutaneous vessel walls of vascultis lesions is consistent with the known chemotactic and destructive role of complement factors in experimental models of angiitis, but it may not necessarily involve a specific immunological process.

Antigen-Antibody Complex↗
PubMed1975

Hereditary angioneurotic oedema.

Three families with hereditary angioneurotic oedema (HANE) are described. Serum CI-INH and C4 immunochemical determinations were performed on 23 members of the families: in 6 persons low CI-INH and C4 levels were found with typical symptoms of HANE, and in one asymptomatic subject. Normal ranges of both proteins for adults, children and newborns are given for comparative purposes. The importance of the early diagnosis and treatment is emphasized.

Adolescent↗
PubMed1984

Immunological variables and acute-phase reactants in patients with ankylosing spondylitis (Bechterew's syndrome) and their relatives.

Serum and EDTA blood from 120 patients with ankylosing spondylitis (Bechterew's syndrome) and serum from 138 first-degree relatives of patients and from 42 adult blood donors were investigated. Increased serum concentrations of IgA and IgG and complement factors C3 and C4 were found in total groups of HLA B27-positive male or female patients compared with controls or relatives. The men had higher serum concentration of IgA and complement factors than the women, whereas IgM concentration was higher in the women. These patterns were found in controls, in relatives and in patients. Increased concentrations of IgA and of C4 were characteristic of all patients whereas IgG and IgM and C3 concentrations were likewise elevated in patients with peripheral joint arthritis/arthropathy. Increased levels of circulating immune complexes (CIC) were associated with peripheral joint arthritis and were strongly correlated with IgG or CRP concentrations in serum. Total haemolytic complement activity in serum was negatively correlated with concentrations of CIC or CRP indicating complement activation in patients with such complexes. No differences in serum concentrations of Ig or complement factor concentrations were seen between HLA B27-positive and negative relatives with normal sacro-iliac joints or between relatives and controls. Strong mutual correlations were seen among IgG, IgM, complement factors, CRP, SAA, sedimentation rate and alpha 2-macroglobulin. When the present findings were combined with our previous results it turned out that AS, and psoriasis with or without arthropathy, and acute anterior uveitis (AAU) in combination with sacro-iliitis, may be described as IgA-related conditions and that increased serum C4 was related to sacro-iliitis in all these disorders.

Adult↗
PubMed1992

Peripheral edema due to increased vascular permeability: a clinical appraisal.

The release of vasoactive substances produces reversible changes of endothelial permeability with consequent edematous syndromes. We present 899 patients referred to our clinic for "non-hydrostatic non-hyponcotic" recurrent edema problems. Personal and family histories were recorded and a complete physical examination was carried out for each patient. In chronic situations laboratory tests [blood cell count, cryoglobulins, thyroid hormones, complement components (C3, C4, C1 inhibitor), total IgE, skin testing] were performed. Four subgroups of angioedema are identified for relevant clinical and etiopathogenetic differences. Seventy-three percent of patients had an urticaria-angioedema syndrome responding to antihistamine and/or corticosteroid treatment (histamine-dependent angioedema). Twenty-three percent had an angioedema related to a deficiency in C1 esterase inhibitor (complement-dependent angioedema). In a minority of patients, angioedema was due to the pharmacological effect of a drug (pharmacological angioedema) or was of a totally unknown origin (idiopathic angioedema). A generalized increase in vascular permeability was reported in 3 patients (systemic capillary leak syndrome). A brief survey of the literature is given with the review of our patients.

Adolescent↗
PubMed2000

Inhibitory effects of newly synthesized active center-directed trypsin-like serine protease inhibitors on the complement system.

OBJECTIVE: To obtain a synthetic anti-complement inhibitor which has stronger activity than FUT-175 (nafamostat mesilate), as a synthetic ester derivative containing amidino and guanidino groups. METHODS: We synthesized several modified compounds of FUT-175. The anti-complement activities were measured using synthetic substrates and complement-mediated hemolysis in vitro. The anti-complement activity in vivo was evaluated via Forssman systemic shock in guinea pigs. RESULTS: FUT-175 inhibited C1r and C1s with IC50s of 1.7x10(-6) and 3.2x10(-7) M, respectively. Inhibitory activities were decreased by substitution of the amidino group with a hydrogen atom (compound 2), but not the guanidino group with a hydrogen atom (compound 3). Compound 6, in which the benzene ring of compound 3 was substituted with a furan ring, inhibited C1r and the complement-mediated hemolysis in high-diluted serum with higher potency than FUT-175. The inhibitory activity of compound 6 in hemolysis was weakened in low diluted serum. Compound 7 had a guanidino group inserted into compound 6; however, Compound 7 strongly inhibited hemolysis even in low-diluted serum, and suppressed Forssman systemic shock more potently than both FUT-175 and compound 6. CONCLUSIONS: These data suggest that the 2-furylcarboxylic acid derivatives have a strong potential for inhibiting the activities of the complement, and the guanidino group was required to retain high inhibitory activities in vivo, and compound 7 is a hopeful anti-complement agent.

Animals↗
PubMed1977

Role of complement in thrombogenesis. I. Complement-dependent coagulation in a model system.

Chondroitin sulphate was used to isolate from plasma a system that clotted with Russell's viper venom, brain extract and activated contact factors. Clotting appeared to depend on concomitant change in C4, C3 and C1s in the system. Brain extract additionally reacted with C9. Reconstitution of specifically defective plasmas suggested a specific role for each of these complement components in clotting.

Antigen-Antibody Reactions↗
PubMed1980

Danazol and stanozolol in long-term prophylactic treatment of hereditary angioedema.

Treatment with 17 alpha-methyltestosterone and with some synthetic androgens prevents attacks of hereditary angioedema (HAE). However, the potential hepatotoxicity of 17 alpha-alkylated androgens raises the problem of long-term prophylactic use of these agents. Therefore we compared the efficacy in preventing HAE attacks of 17 alpha-alkylated steroids (danazol and stanozolol) with non-17 alpha-alkylated derivatives (quinbolone, nandrolone decanoate and mesterolone). As the latter group proved ineffective, it seems that a drug's efficacy in preventing HAE attacks is connected to its 17 alpha-alkylation. Moreover, our long-term observations with the minimum effective dose of danazol seem to indicate the absence of important collateral effects.

Adult↗
PubMed1988

Synthetic peptide inhibitors of complement serine proteases--I. Identification of functionally equivalent protease inhibitor sequences in serpins and inhibition of C1s and D.

Sequence homology comparisons between serum serine protease inhibitors led to the prediction that the C-terminal sequences are functionally equivalent and represent an essential protease binding domain. Inhibition of complement serine protease D cleavage of factor B and of C1s cleavage of C4 by synthetic peptides containing sequences from the C-termini of three serum serine protease inhibitors supports this prediction. These functionally equivalent peptides represent a new class of inhibitors of D and C1s as well as other serum serine proteases.

Amino Acid Sequence↗