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RESEARCH PRODUCT
Disulfide bridge formation between C1q and IgG in vitro.
Harry MartinMarcus KaulMichael Loossubject
MaleReducing agentImmunologyGuinea Pigschemical and pharmacologic phenomenaBiologyIn Vitro Techniquesurologic and male genital diseasesDialysis tubingfluids and secretionsimmune system diseasesImmunology and AllergyAnimalsSulfhydryl Compoundsskin and connective tissue diseasesComplement C1qComplement ActivationGel electrophoresisComplement C1qIn vitroBiochemistryImmunoglobulin Gbiology.proteinElectrophoresis Polyacrylamide GelFemaleAntibodyDialysis (biochemistry)Cysteinedescription
The globular heads of C1q are known to possess free-SH groups. Here we show that these groups, which are concealed in the native molecule, are exposed by interaction of C1q with dialysis membrane. During iodination, I+ and I2 oxidize these sulfhydryls to produce disulfide-linked C1q aggregates. Approximately 15% of C1q bound to immunoglobulin aggregates is resistant to high conductivity elution and reducing agent is required to release it. These data show that dialysis, adsorption to Ig and iodination of C1q result in structural and functional changes in the molecule, and suggest a mechanism by which these changes occur. Disulfide bridging between C1q and IgG in vitro suggests that this may be a normal physiological function of C1q for which the free cysteines of human, mouse and guinea pig C1q have been conserved.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1990-08-01 | European journal of immunology |