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PubMed1987

In vitro effects of organic solvents on immunity indicators in serum.

Serum treatment in vitro with organic solvents (chloroform, ether, toluene) failed to produce an effect on immunoglobulin levels and activity. After chloroform and ether treatment, no complement activity could be determined, with chloroform-treated serum beginning to express anticomplement activity against autologous, allogenic and xenogenic sera. The classical pathway of complement activation (C1, C4, C2, C3) was primarily inhibited, whereas the alternative pathway remained unaffected. Chloroform-treated sera exhibited significantly declined levels of C1-INH, C3 and C4 as well as of circulating immune complexes. Toluene did not influence any of the parameters tested, while ether blocked complement activity without affecting either the concentration or activity of the other components under investigation. The obtained findings are discussed from the aspect of organic solvent applications in preparing immune products and determining immunity indicators in the serum or other biological fluids.

Antibodies↗
PubMed1987

[A case report of hereditary angioedema and studies on the serum components of complement, C1-inactivator and proteinase inhibitors during edema attack].

Sixteen years old girl was admitted because of for the past ten years' frequent edema attack and abdominal pain. Laboratory examination revealed hypocomplementemia, marked depletion of the fourth component of complement and low level of C1-inactivator. Familial studies revealed that her mother was also hypocomplementemic and in low level of C1-inactivator. Serial studies performed on the alterlation of components of complement, C1-inactivator, alpha 1-antitrypsin, antithrombin III, and alpha 2-macroglobulin during edema attack. The fourth component of complement and C1-inactivator were markedly depleted in remission and attack. Remarkable depletion was found in antithrombin III and esterase inhibition activity of C1-inactivator during attack. In contrast, alpha 1-antitrypsin and alpha 2-macroglobulin did not change. The present study may explain that Hageman factor fragments, activated by C1s, promotes kinin generation via kalikrein activation. And the condition that complete functional deficiency of C1-inactivator was main role in this circuit. Fibrynolysis and late components of complement was less influence on edema attack.

Adolescent↗
PubMed1979

Diagnosis and management of hereditary angioedema (HAE).

In summary, HAE is a dominantly inherited form of angioedema which is manifested by nonpainful, nonerythematous, nonpruritic and nonpitting swelling of the extremities, face, gastrointestinal and respiratory tracts unaccompanied by urticaria. These patients have deficient activity of the C1 INH and the laboratory diagnosis can be easily made by finding low C4 and C1 inh levels during an attack. Effective and specific therapy is now available that prevents the clinical syndrome and corrects the serologic hallmarks of the disease.

Airway Obstruction↗
PubMedDate not supplied

[Immunologic parameters in chronic urticaria].

Urticaria and angioedema are common disorders that affect approximately 1/5 of the population at some stage in their lives. Although the clinical diagnosis of this disorder is made without difficulty, its etiology and pathogenesis remain obscure. Extensive clinical studies and the application of different laboratory techniques seldom manage to detect the etiology of chronic urticaria or determine its supposed pathogenic mechanism. Thus, a large number of causal agents have been held responsible for the symptoms of chronic urticaria and/or chronic urticaria and angioedema and for the variety of immunologic and nonimmunologic factors involved in its pathogenesis. The controversial laboratory findings in this type of patients prompted us to undertake this study on 48 subjects with chronic urticaria and/or angioedema. We studied the levels of serum immunoglobulins (IgG, IgA, IgM and IgE), the haemolytic activity of the complement (CH50), the levels of the complement components (C1 inhibitor, C3 and C4), the possible presence of circulating immune complexes and the percentages of the T lymphoid subpopulations (using OKT3, OKT4 and OKT8 markers) and the B population. The results obtained showed an alteration of the complement (CH50) and of some of its components (C3 and C4) as well as of the cytotoxic/suppressor lymphocyte subpopulation (OKT8).

Adult↗
PubMedDate not supplied

Prekallikrein activation in the adult respiratory distress syndrome.

Prekallikrein is the zymogen form of plasma kallikrein, a proteolytic enzyme of the contact system of blood coagulation, fibrinolysis and kinin formation. To assess whether prekallikrein was activated in the adult respiratory distress syndrome (ARDS), we examined plasma samples from 12 critically ill patients including five individuals with ARDS. Using the ratio between functional prekallikrein and prekallikrein-kallikrein antigen as an index for prekallikrein activation, we found that prekallikrein was extensively activated in patients with ARDS, while this was significantly less in the case of critically ill patients without ARDS. Following activation of prekallikrein in plasma, kallikrein reacts with its substrates and with protease inhibitors, among which the alpha 2-glycoprotein C1-inhibitor. Thus, we examined whether C1-inhibitor of critically ill individuals was modified in a way suggesting that it had reacted with kallikrein. Such a modification was found in the five patients with ARDS, while it was not detectable in the seven patients without ARDS. This observation further confirmed the activation of prekallikrein in patients with ARDS. We suggest that plasma kallikrein-mediated reactions, which include bradykinin release and neutrophil activation, may contribute to the pathogenesis of ARDS.

Adolescent↗
PubMed1985

Determination of C1s-C1 inhibitor complexes in plasma by means of an enzyme linked immunosorbent assay.

An enzyme linked differential antibody immunosorbent assay for the quantitation of the C1s-C1 inhibitor complex has been developed. A study of the assays' performance under various conditions has shown that before use in the assay, it is imperative to remove competing forms of C1s from the samples to be tested. This is conveniently achieved in human plasma or serum by polyethylene glycol precipitation of the C1qrs, since the C1s-C1 inhibitor complex remains soluble and can be assayed in the supernatant solution. The detection limit of the assay in the plasma milieu is 0.1 mg/l, and the concentrations of the C1s-C1 inhibitor complex were found to be 1 mg/l in citrated plasma and 2 mg/l in serum. Activation of the fibrinolytic system in vivo does not seem to result in any appreciable C1 activation, since there was no concomitant major change in the plasma concentration of the C1s-C1 inhibitor complex.

Adult↗
PubMed1985

Primary structure of the reactive site of human C1-inhibitor.

Human C1-inhibitor (C1-Inh) forms an equimolar complex with complement proteinase C1s that is resistant to dissociation by sodium dodecyl sulfate. The formation of this stable complex results in the cleavage of a peptide bond near the carboxyl terminus of the inhibitor and, whereas the bulk of C1-Inh remains covalently bound to the light chain of C1s, the postcomplex inhibitor peptide can be isolated under denaturing conditions. We have sequenced the amino-terminal region of this peptide and deduced that it represents the carboxyl-terminal side of the reactive site of C1-Inh. Limited proteolysis of C1-Inh by Crotalus atrox protease results in an active derivative lacking an amino-terminal peptide of 36 residues. Further proteolysis of this derivative with Pseudomonas aeruginosa elastase inactivates the inhibitor and a peptide is released. The amino-terminal sequence of this peptide overlaps with that of the postcomplex peptide and indicates that the residue imparting primary specificity to the inhibitor is arginine.

Amino Acid Sequence↗
PubMed1985

[Current diagnostic possibilities in hereditary angioedema and acquired angioedema].

Amidolytic assays for the determination of C1 esterase inhibitor have been proposed some years ago; however, the substrates employed lacked sensitivity. The recent development of a C1 esterase-sensitive substrate (N-alpha-methoxycarbonyl-l-lysyl(epsilon-CBO)-glycyl-arginyl-4-nit roanilide) provides a method that can be routinely used. Any interferences with other plasma proteases could not be observed. Normal range was ascertained to be 1.48 +/- 0.23 kU/l; within-run precision revealed C.V.'s of 1.74% (for the normal range) and 7.3% (for the pathological range). This method can be considered most suitable for functional determination of C1 esterase inhibitor and is superior to the determination of antikallikrein activity. To point out to the diagnostic relevance of a functional C1 esterase inhibitor assay some examples are illustrated.

Angioedema↗
PubMed1979

[Clinical and immunological studies on acquired heat contact urticaria (author's transl)].

A case of localized urticaria in an otherwise healthy young woman, produced only by direct contact of the skin with heat, is described. The minimal temperature of urtication was 44 degrees C (immersion of the forearm in hot water for 5 min). Redness and painful oedema immediately developed without reflex flare. Total serum IgG, IgA, IgM, IgE, complement factors C3 and C4, and alpha1-antitrypsin were in the normal range, whereas the C1-inhibitor level was slightly decreased. There was no evidence of circulating immune complexes in the serum. A skin test and a RAST with house dust were positive, but there were no signs of respiratory atopy. An attempt for passive transfer of heat urticaria into the abdominal skin of a rhesus monkey failed, but was successful for house dust. A treatment trial with ketotifen, a new, perorally acting anti-allergic drug, was poorly effective, but dexchlorpheniramine maleate, a classical antihistaminic, in a dose of 12 mg daily completely suppressed the swelling evoked by heat, but not the erythema, suggesting that other tissue or plasma factors than histamine may be involved in the mechanism of heat urticaria in this patient.

Adult↗
PubMed1985

The prognostic value of preoperative serum immunoglobulin and complement component concentrations in patients with gastric carcinoma.

Patients with and without recurrence of gastric carcinoma after potentially curative resection (stages I, II and III--pTNM) were studied. The preoperative serum concentrations of IgG and C1-INH were significantly different in a group of 22 patients with recurrence and a group of 33 survivors who were free from recurrence. The patients with recurrence had lower concentrations of IgG (8.3 +/- 2.6 g/l) and higher concentrations of C1-INH (0.4 +/- 0.07 g/l) than the recurrence-free survivors (10.8 +/- 3.5 and 0.35 +/- 0.08 g/l, respectively). The results indicate that preoperative quantitation of serum immunoglobulins and complement components may be helpful in predicting the prognosis in gastric carcinoma.

Aged↗
PubMed1985

The prognostic value of postoperative serum immunoglobulin and complement component concentrations following gastric resection for carcinoma.

Patients clinically free from disease after potentially curative resection of gastric carcinoma, stages I, II and III (pTNM) were studied. The concentrations of immunoglobulins and complement components were quantified at 3-month intervals during the first year after surgery. The values in the individual patients showed no systematic variation with time while there was no clinical evidence of disease. The mean concentrations of C4 and C1-INH, however, were higher in 22 patients with later recurrence (0.43 +/- 0.10 and 0.43 +/- 0.07 g/l, respectively) than in 34 patients who were alive and disease-free at follow-up (0.36 +/- 0.07 and 0.36 +/- 0.04 g/l). The mean serum concentrations of IgG, IgA, IgM and C3 showed no intergroup difference. High levels of C4 and C1-INH postoperatively apparently indicate that the patient still harbours malignant disease with poor prognosis.

Adult↗
PubMed1985

Depressed classical complement pathway activities in chronic lymphocytic leukaemia.

Haemolytic activities of the classical and alternative complement pathways, and levels of C1, C4, C3, factor B and C1 inhibitor (C1-INH) were measured in 85 serum samples from 46 patients with chronic lymphocytic leukaemia (CLL). Significantly decreased mean C1 and C4 levels were found, and the haemolytic activities of these components were low or low normal in more than 50% of the sera tested. In 15 sera from 5 patients a complement profile characteristic of acquired C1-IHN deficiency was observed. These results indicate that the depression of the activity of the classical complement pathway is a frequently occurring feature in CLL.

Antigen-Antibody Complex↗
PubMed1985

The role of C1, C1-inactivator and C4 in modulating immune precipitation.

To clarify the mechanism of inhibition of immune precipitation by early components of the classical pathway of complement, aggregation of 125I-BSA-rabbit-anti-BSA antibody complexes was performed in the presence of purified C1, C1-inactivator (C1-In) and C4. C1 delayed the rate of immune precipitation in a concentration dependent manner. This phenomenon was not influenced by the presence of 0.3 mM p-nitrophenyl-p-guanidinobenzoate (NPGB) which inhibits C1 activation. The antiaggregational effect of C1 was reversed by 10 mM EDTA and by C1-In at a C1-In/C1 molar ratio of greater than or equal to 4/1. C1-In was not effective when the reaction was performed in the presence of NPGB. Thus, although the inhibitory effect of C1 on immune precipitation was not dependent upon C1 activation, the formation of C1 was required to observe the effect of C1-In. The addition of C4 to C1 did not modify the slow aggregation of complexes, even when a limiting concentration of C1 was used. C1-In and EDTA were both able to cause similar rapid precipitation of complexes prepared in the presence of C1 and C4, demonstrating that C4 did not play a significant role in delaying the precipitation reaction. However, soluble complexes prepared in the presence of C1 and C4 were specifically precipitated by the addition of excess anti-C4 antibody, attesting to the binding of C4 to immune complexes. These observations suggest that the processing of immune complexes in vivo may not be similar in different classical pathway complement deficiency states.

Animals↗
PubMed1977

Alternative complement pathway in bovine serum: lysis of human erythrocytes.

The hemolysis of unsensitized human erythrocytes by fresh bovine serums was investigated. Lysis occurred in ethylene glycol bis-amino tetraacetate buffers and with serums depleted of Clq. Serums extensively absorbed with packed human erythrocytes at 0 C effectively lysed human erythrocytes, but optimal lytic capacity required target cells "sensitized" with a heat-stable serum factor. Lysis did not occur with serums absorbed with zymosan at 17 C or heat inactivated at 50 C. These results indicate that human erythrocytes can activate the alternative pathway of complement in bovine serums. Lysis can proceed in the apparent absence of antibodies, although their presence may enhance the reaction.

ABO Blood-Group System↗