Inhibitory effect of bilirubin on complement-mediated hemolysis
| Autor: | Adriana M. Almará, Sandra Mónica María Arriaga, Aldo D. Mottino |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
Erythrocytes
Bilirubin Biophysics Inhibitory postsynaptic potential Biochemistry Hemolysis Immunoenzyme Techniques Classical complement pathway chemistry.chemical_compound Complement C1 medicine Animals Humans Molecular Biology Cells Cultured chemistry.chemical_classification Complement Inactivator Proteins Sheep medicine.diagnostic_test Complement C1q Complement System Proteins Bile Pigments medicine.disease In vitro Enzyme chemistry Immunoglobulin M Immunoassay Immunoglobulin G |
| Zdroj: | Biochimica et biophysica acta. 1473(2-3) |
| ISSN: | 0006-3002 |
| Popis: | We investigated the in vitro action of the bile pigments, unconjugated bilirubin (UB) and bilirubin monoglucuronide (BMG) on complement (C) cascade reaction. Both UB and BMG inhibited hemolysis in the classical pathway (CP) in a dose-dependent manner at low micromolar concentrations, UB showing a stronger effect than BMG. The analysis of the action of UB on the hemolytic activity of the C1, C4, C2 and C-EDTA components of the C cascade revealed that the C1 step was the most inhibited. An enzyme immunoassay was developed to evaluate the effect of UB on the binding of C1q, one of the subcomponents of C1, to human IgM and IgG. The study demonstrated that the unconjugated pigment interferes both the C1q-IgM and -IgG interactions, thus tentatively explaining the inhibitory action of UB on hemolytic activity of C1. We conclude that the anti-complement effect of UB is mainly exerted on the C1 component, the recognition unit of CP. The potential clinical implication of the reported effects in hyperbilirubinemia is discussed. |
| Databáze: | OpenAIRE |
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