PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Complement Inactivating Agents”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed2026

Efficacy and Safety of the C3 Inhibitor Pegcetacoplan in Paroxysmal Nocturnal Hemoglobinuria: A Systematic Review and Meta-Analysis.

OBJECTIVE: To evaluate the efficacy and safety of the complement C3 inhibitor pegcetacoplan in patients with paroxysmal nocturnal hemoglobinuria (PNH). METHODS: PubMed, Embase, Web of Science, and Cochrane Library were systematically searched for studies reporting pegcetacoplan use in PNH. Outcomes included transfusion-requirement, hemoglobin normalization, mean hemoglobin levels, lactate dehydrogenase normalization, reticulocyte count normalization, and safety endpoints. Pooled proportions with 95% confidence intervals were calculated using random-effects models, and heterogeneity was assessed using the I2 statistic. RESULTS: Five studies comprising 271 patients were included. Transfusion avoidance was observed in 80.6% of patients, with a pooled transfusion-requirement rate of 19.4%. LDH normalization occurred in 68.5% of patients (I2 = 0%). Hemoglobin normalization was observed in 42.9%, while reticulocyte count normalization reached 66%. Any-grade adverse events occurred in 83.5% of patients, most commonly pyrexia, headache, and dizziness. Serious adverse events occurred in 16.6%, decreasing to 12% after sensitivity analysis. Breakthrough hemolysis was reported in 14.8%, and infections in 17%. CONCLUSION: Pegcetacoplan demonstrates consistent efficacy signals across key hematologic endpoints and an acceptable safety profile, supporting its potential role as an important therapeutic option, particularly in patients with persistent extravascular hemolysis despite C5 inhibition.

Humans↗
PubMed1979

Serum opsonic activity in rodent malaria: functional and immunochemical characteristics in vitro.

The functional and immunochemical characteristics of serum opsonic activity in rodent malaria were examined in the present study. Schizont- and late trophozoite-enriched populations of Plasmodium berghei-infected red blood cells (IRBC) were isolated on a Ficoll density-gradient and used in an in vitro phagocytosis system composed of serum and monolayer cultures of rat peritoneal macrophages. Hyperimmune serum augmented the phagocytosis of IRBC to a greater degree than did nonimmune serum. When either IRBC or macrophages were pre-incubated with serum, the phagocytosis-promoting factors acted on the IRBC rather than on the macrophages in a manner characteristic of serum opsonins. The opsonic activity was specific for IRBC since noninfected red blood cells were rarely phagocytized and were unable to absorb opsonic activity from serum. The opsonic activity of both hyperimmune and nonimmune sera was heat stable, and unaffected by agents known to inactivate or inhibit complement (cobra venom factor and ethylenediaminetetraacetic acid). Finally, the opsonic activity was identified in preparations of purified IgG isolated from both hyperimmune and nonimmune sera.

Animals↗
PubMed1977

[Relationship between the chemical structure and the biological activity of antibodies against the foot-and-mouth disease virus].

Investigated was the effect of various amino agents (stained and phthalic anhydride and sulfopicric acid) on the complement-and antigen-fixing activity of IgG and IgM antibodies isolated from guinea pig sera, the donor animals being hyperimmunzed with type O, strain Polyana, of the foot-and-mouth disease virus, At the moderate modification (75-86 per cent acetylation, and 36-40 per cent 'phthalation') of the primary amino groups the foot-and-mouth disease antibodies retained only half of the conjugation caused greater and complete loss of this activity. IgG and IgM showed almost equal specificity with regard to the antigen that had induced them. The lowered complement-fixing capacity was shown to have no specific effect on the primary relation of the foot-and-mouth disease virus to the antibody. Chemical modifying agents inactivated the specific small, strongly defined complement-fixing zones in the Fc-fragment of the foot-and-mouth disease antibody molecule.

Acetaldehyde↗
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↗
PubMed1979

Chemotactic factor inactivation by the myeloperoxidase-hydrogen peroxide-halide system.

Polymorphonuclear leukocytes may modulate the acute inflammatory response by the secretion of enzymes capable of inactivating mediators of inflammation. The ability of the myeloperoxidase-H(2)O(2)-halide system of the neutrophil to inactivate chemoattractants was examined using both a radioassay and a morphologic assay of chemotaxis. Incubation of either a complement-derived agent, C5a, or a synthetic formyl-methionyl peptide chemoattractant with the myeloperoxidase system for 15 min at 37 degrees C resulted in essentially complete loss of chemotactic activity. Inactivation was dependent on enzymatically active myeloperoxidase, H(2)O(2) or a peroxide-generating enzyme system, and a halide cofactor. It was blocked by agents which inhibit peroxidase (azide) or degrade H(2)O(2) (catalase). Inactivation of chemoattractants was time-dependent, reaching maximal levels within 1-5 min, and temperature-dependent with no significant inactivation occurring at 0 degrees C. H(2)O(2) alone had no significant inactivating ability at concentrations as high as 10 mM, whereas in the presence of myeloperoxidase and a halide, 0.1 muM H(2)O(2) showed significant activity and 10 muM H(2)O(2) caused complete inactivation. On a molar basis, the order of effectiveness of the halide cofactors was Br(-) > I(-) > Cl(-), although only chloride was fully active at physiologic concentrations. Neutrophils stimulated by phagocytosis or by membraneperturbing agents secrete enzymatic constituents, including myeloperoxidase, and metabolic products such as H(2)O(2). Thus, it is suggested that the myeloperoxidase system acting at an extracellular site serves as an inflammatory control mechanism by virtue of its ability to inactivate neutrophil chemoattractants.

Animals↗
PubMed1978

Studies on some biologically active dextrans.

The relationship between the structures of six native dextrans and their effects on nonspecific resistance to infection (n.s.r.i.) in mice and also anticomplementary activity has been studied. The data obtained showed that the n.s.r.i. activity of dextrans generally increased with increase of extent of branching, but no direct correlation between these two factors was found. Data on exodextranase-catalyzed hydrolysis of dextrans suggest that the length of the outer chains may be important for the n.s.r.i. activity of the dextrans. Dextrans characterized by a significant extent of branching were anticomplementary, but no relationship between extent of branching and anticomplementary activity was observed.

Animals↗
PubMed1978

The immunopharmacologic and anti-inflammatory properties of RMI 9563 with special reference to its effect on the complement system.

The immunopharmacology of RMI 9563 - bis[3-(diethylamino)propyl]fluoranthene-3,9-dicarboxylate dihydrochloride--has been described. The compound, when given parenterally, inhibited several cell-mediated immune responses (EAE, tuberculin skin reaction, adjuvant arthritis) in rats, enhanced IgM and IgG antibody-producing cells in mice, and displayed anti-inflammatory activity in several models (carrageenan paw edema, adjuvant arthritis, direct passive Arthus reaction--a model of inflammation that is immunologically induced and complement-dependent). RMI 9563 suppressed the activation of complement in vitro by the selective inhibition of C1 esterase.

Animals↗
PubMed1976

[FAB immunoglobulin fragments. I. The comparative characteristics of the serological and virus-neutralizing properties of a gamma globulin against tick-borne encephalitis and of the FAB fragments isolated from it].

A comparative study was made of the serological properties and virus-neutralizing activity of antiencephalitis gamma-globulin and Fab-fragments isolated from it by gel-filtration. Horse immunoglobulins against the autumno-summer tick-borne encephalitis virus could be disintegrated with the aid of papaine to monovalent Fab-fragments which (according to the complement fixation reaction, the test of suppression of the complement fixation, and the HAIT) retained the serological activity whose level was compared with that of the serological activity of gamma-globulin. Fab-fragments possessed a marked virus-neutralizing activity. The mean value of a logarithm of the neutralization index was 2.65 +/- 0.2 for Fab-fragments and 3.74 +/- 0.38 for gamma-globulin (P less than 0.01).

Animals↗
PubMed1979

A simple method to detect complement receptors using baker's yeast: Y C rosettes.

A technique is described to identify complement-receptor-bearing cells, using serum-treated baker's yeast as a ligand. The method consists of incubation of heat-killed baker's yeasts with fresh AB normal serum, freezing, thawing, and washing of the particles, followed by mixing with the cells. Serum is required to coat the yeasts for the rosette formation. Experiments designed to establish the serum factors responsible for the attachment of the particles to cells show that heat inactivation, chelating agents, or anti-C3 treatment prevent rosette formation. This is taken as evidence that yeasts (Y) are coated with complement (C) to compose the reagent for the YC rosette technique. The application of this technique to twenty-five normal individuals demonstrated that a mean of 11.6 per 100 lymphocytes (+/- 4.3) form rosettes; absolute number: 275 (+/- 160) rosette-forming lymphocytes per mm3. Either AB or autologous fresh serum can be used to coat the yeasts. A combined technique for YC plus E rosettes can be performed allowing the identification and enumeration of four populations of lymphocytes: (a) those having receptors for sheep erythrocytes, (b) complement-receptor-bearing lymphocytes, (c) those having both receptors (D lymphocytes), and (d) non-rosette-forming non-phagocytic cells.

Adult↗
PubMed1979

Adherence, augmented adherence, and aggregation of polymorphonuclear leukocytes.

Adherence of polymorphonuclear leukocytes to nylon fiber was found to be plasma-independent and distinct from the processes of augmented adherence, leukocyte aggregation, and inhibition of random leukocyte migration, all of which are dependent on "activated" plasma. Nylon fibers were unable to "activate" plasma, in contrast to the complement-activating agent zymosan. Prior incubation of plasma with antiserum to the third component of complement (C3) inhibited aggregation of polymorphonuclear leukocytes by plasma incubated with zymosan, and heat-inactivation blocked augmentation of adherence by treatment of plasma with zymosan.

Adult↗