Complement studies in children with treated coeliac disease after gluten challenge

Changes of the complement components in the sera of 13 children with treated coeliac disease were studied after gluten challenge. The levels of C 1 and C3-activator (factor B) were significantly decreased at 4 h after the challenge, as were the levels of total complement (CH 50) and the components C 1, C 4 and C 1-inactivator at 8 h. After 24 h most values returned to normal but there was another significant decrease in serum C 4 after 24 h, and for CH 50, C 1, C 2 and C 4 after 48 h.

Control of complement activation in membranous and membranoproliferative glomerulonephritis

Renal biopsy specimens from 22 membranous (MGN) and 19 membranoproliferative glomerulonephritis (MPGN) patients were examined for the presence of the three regulators of the complement system; C1- inhibitor (C1--INH), C3b inactivator (C3b-INA), and beta 1H. The serum concentrations of these proteins, at the time of biopsy, were also measured. To study the modulation of complement activation by these three control proteins in MGN and MPGN, we examined the relationship between each control protein and the protein whose activity it regulates, in four ways; (a) the concordance between the presence of the control proteins and the components regulated was studied, (b) the correlations in intensity of deposition of the control and complement proteins were measured, (c) the patterns of distribution of the proteins within the glomeruli were compared, and (d) the serum levels of control proteins and components, regulated were examined. C1--INH (23 of 35 biopsies) and beta 1H (34 of 36 biopsies) were frequently deposited in both disease groups. C3b-INA was found only rarely in MPGN (4 of 19 biopsies). This is probably because the former two proteins modulate complement activation stoichiometrically, whereas C3b-INA acts enzymatically. A relationship was demonstrated between C1--INH and C1s and between beta 1H and C3 in both groups, but no such relationship was found between C3bINA and C3. Conclusion. There is no generalized deficiency in modulation of complement activation in MGN or MPGN.

Replacement therapy in hereditary angioedema: successful treatment of acute episodes of angioedema with partly purified C1 inhibitor

Although considerable progress has been made during the past two decades in the use of androgens to prevent attacks of hereditary angioedema, replacement of the deficient C1-inhibitor protein would provide a useful menas of treatment once an attack has begun. We studied the clinical use of C1 inhibitor that was partly purified on a large scale from pooled plasma. The in vivo efficacy and safety of this protein concentrate were evaluated during 11 intravenous infusions in eight patients with hereditary angioedema. Three patients received the C1-inhibitor preparation during an asymptomatic period. Increases in serum C4 activity provided evidence of the biologic activity of the infused inhibitor. Intravenous administration of the concentrate during acute abdominal or laryngeal attacks of hereditary angioedema in five patients resulted in abatement of symptoms in addition to increased serum C4 activity. No untoward effects of the intravenous administration of the C1 inhibitor were observed in these eight patients. Thus, this C1-inhibitor preparation seems to offer the potential for safe, effective replacement therapy and may provide a means of controlling an attack of hereditary angioedema that is in progress.

[The dynamics and its clinical significance of complement system, especially alternative pathway related to normal human pregnancy, delivery, puerperium and fetus (author's transl)]

The author studied human complement system, especially alternative pathway as a primitive biological defense system, in maternal serum during normal pregnancy, delivery and puerperium. The results obtained were as follows. 1. The mean value of hemolytic activity of alternative pathway (AlCH50) in healthy women was 18.3 +/- 1.1. This value was increased gradually in progress of gestational stages up to 26.6 +/- 2.3 of the average in the last trimester. Stochastically, significant differences about this value was noted between in the first trimester and in the last. This AlCH50 is decreased temporarily at delivery, and it was increased again rapidly, then went down to normal range about one month after delivery. 2. The average of immunochemical C3PA by SRID method during pregnancy was 22.5 +/- 0.4 mg/dl. It was significantly higher than the average 18.1 +/- 0.4 mg/dl of 59 healthy women. C3PA was noted to remain high level constantly during pregnancy. This C3PA level after delivery was observed to take a similar pattern as AlCH50. 3. beta 1C/1A globulin (C3) in 19 healthy women was 60.7 +/- 2.1 mg/dl. This C3 was also increased gradually during pregnancy up to maximum level of 87.5 +/- 2.8 mg/dl at the 3rd trimester. 4. Classical pathway (CH50, C4 and Cl INA) and fetal complement level were investigated at the same time and discussed here.

Response of variant hereditary angioedema phenotypes to danazol therapy. Genetic implications

Hereditary angioedema (HAE), an auto-somal dominant disorder characterized by attacks of episodic edema is associated with decreased functional levels of the C1 esterase inhibitor. Approximately 85% of patients have lowered antigen levels of a normal inhibitor protein. 15% of patients have normal or elevated antigenic levels of functionless protein. We have examined the response to danazol therapy of patients with the variant HAE phenotypes possessing the abnormal protein in an effort to determine if these patients possess a normal structural C1 inhibitor allele. Four patients with a variant HAE phenotype were treated successfully with danazol. In two patients, distinguished by the presence of a functionless, albumin-bound, C1 inhibitor (phenotype 2), phenotypic analysis of the danazol response by bidirectional immunoelectrophoresis revealed the appearance of the normal C1 inhibitor gene product during danazol therapy. This relatively cathodal C1 inhibitor peak appears in conjunction with the development of nearly normal functional activity. All of the functional C1 inhibitory activity which appeared in the phenotype 2 treatment serum was associated with the electrophoretically normal inhibitor. This normal protein could be separated from the functionless inhibitor protein by immunoadsorption and molecular sieve chromatography. Danazol therapy of the two patients with an electrophoretically normal, functionless C1 inhibitor (phenotype 3) also resulted in a clinical remission associated with development of a significant increment in functional serum C1 inhibitory activity and C1 inhibitor protein. These findings demonstrate that these two HAE phenotypic variants are heterozygous for the normal serum C1 inhibitor, a finding which was not apparent before phenotypic analysis of this serum during danazol therapy. These data provide strong evidence for a basic similarity between the common form of HAE and its phenotypic variants. They also suggest that a structural gene lesion may result in the abnormalities of serum C1 inhibitor function and disease expression in all three of these HAE phenotypes.

Evidence for glomerular modulation of complement activation

Using indirect immunofluorescence, three regulatory proteins of the complement system, C1-inhibitor (C1-INH), C3b inactivator (C3bINA) and beta 1H globulin have been detected in the glomeruli of patients with glomerulonephritis associated with complement activation. C1-INH and beta 1H were found frequently but C3bINA was rarely detected (only 14 biopsies). beta 1H globulin and C3b inactivator which modulate C3b activity were never found in the absence of C3, but C1-INH was sometimes found in the absence of C1s. The patterns for staining for C1s and C1-INH, C3 and beta 1H were almost identical suggesting that the regulatory proteins are binding to the proteins they regulate, as has been demonstrated in vitro. Thus, in tissues undergoing complement-mediated tissue damage, the extent of complement activation is controlled by the normal regulatory mechanisms.

Familial deficiency of two subunits of the first component of complement. C1r and C1s associated with a lupus erythematosus-like disease

Complete absence of C1r and almost complete absence of C1s were found in 4 of 8 living siblings. Two of the 4 suffer from a syndrome that combines discoid lupus erythematosus and nondeforming rheumatoid-like arthritis; one of the siblings has mild nephritis. The other 2 C1 deficient family members are clinically well. Evidence from this and other families suggests that deficiency of C1 components or C4 is associated with higher risk of developing a lupus-like disease than is deficiency of C2.

Acquired angioedema associated with rectal carcinoma and its response to danazol therapy. Acquired angioedema treated with danazol

Cases of the acquired form of angioedema have been recognized as a separate entity since 1972. Previously reported cases have been related to various hematologic malignancies. We have recently studied a patient with rectal carcinoma who manifests a complement pattern compatible with the acquired form of angioedema. No previous personal or family history of allergic disease or angioedema was present. Because the episodes of angioedema were laryngeal in location and required emergency intubation to maintain an adequate airway, a trial of danazol prophylaxis, which has been shown to be effective in hereditary angioedema, was undertaken. His beneficial response to this form of therapy is also documented.

[Treatment of hereditary angioneurotic edema with androgens]

Hereditary angioedema (HANE) is a rare, life-threatening disease due to the deficiency of C1 inhibitor (C1 Inh). Androgen therapy has been recently shown to be effective for prophylaxis of Hane attacks. Since life-long androgen therapy may be hazardous, this study was designed to define the minimal doses required for effectiveness. Ten patients from six different families were treated during cumulative 73 months by danazol and/for methandrostenolone. One tablet/day of either drug was the minimal requirement to prevent any attack in all patients. When 3 tablets/day were given, complement abnormalities were simultaneously rapidly reversed. When 1 tablet/day was given the biological effect was barely detectable, except for C2. Serum C2 levels may, therefore, represent the best criteria of androgen therapy effectiveness. Thus, an excellent clinical result can be obtained with much lower doses of androgens than previously stated. This result seemed important with respect to the serious dose-dependent risk of androgens.

Profiles of serum complement in patients with hepatobiliary diseases

CH50 and the concentrations of C3, C4, C1 INH and factor B have been measured in sera from 34 control subjects and 178 patients with various hepatobiliary diseases, including primary biliary cirrhosis (PBC), chronic active hepatitis (CAH), cryptogenic cirrhosis (CC), alcoholic liver disease (ALD), Wilson's disease (WD), large duct biliary obstruction (LDBO) and viral hepatitis (VH). CH50 was decreased in CAH and CC. C3 was increased in PBC, LDBO and VH and decreased in CAH and CC. C4 was decreased in PBC, CAH, ALD and WD. C1 INH was increased in PBC, CAH, ALD, LDBO and VH. Factor B was increased in LDBO and VH and decreased in CC. In none of the patient groups was the mean C4 level increased or the mean C1 INH level decreased. All 5 indices of serum complement were lower in ascitic than nonascitic patients. Data on serum complement were similar in HBsAg positive and negative VH. Discriminant analysis facilitated separation of all the patient groups on the basis of complement data, except PBC and VA. Analysis of data using a within-group correlation matrix revealed a significant negative correlation between C4, the most discriminating variable of serum complement in CAH, and gamma-globulin concentration in CAH. The possible contribution of factors such as activation of complement, impaired hepatic synthesis of complement components, an acute phase response and cholestasis to altered serum complement profiles in different hepatobiliary diseases is discussed.

An investigation of the complement system in patients with periodic disease (results from 29 cases)

The complement system was investigated in 29 patients suffering from authentic periodic disease. A statistically significant increase in C4, also in total complement and C3 could be demonstrated. It is possible that the increase in C4 was due to the macrophages which are always present in the infiltrates of periodic disease. This biological observation is of clear practical importance for the diagnosis of the condition both before and after colchicine therapy.

Haemostatic and complement changes in a family with 'allergic' disorders

A family with allergic manifestations, haemostatic disturbances, total absence of haemolytic activity of the complement system and low IgG levels is described. It is suggested that this functional abnormality of the complement system and the decreased level of immunoglobulin G may be due to immune complex reactions.

Involvement of complement in atopic dermatitis

There is little information about the role of complement in atopic dermatitis (AD). We studied the levels of both normal complement components and activation products in peripheral blood of patients with mild to intermediate disease. 35 patients had not received systemic or topical steroid therapy 6 weeks prior to blood collection. C3, C4 and C1 INA were determined in serum by radioimmunodiffusion. C3a and C5a levels were measured in EDTA plasma by radioimmunoassay. Compared to healthy non-atopic controls C3, C4 and C1 INA were found to be increased significantly. There was a tendency towards increased C3a levels but the difference was not significant. No measurable amounts of C5a were detected. Elevations of C3a were correlated with elevated levels of C3. The results suggest that the complement system participates in the inflammatory process in AD.