Novel methods to determine complement activation in human serum induced by the complex of Dezamizumab and serum amyloid P.
J Biol Chem
; 297(4): 101136, 2021 10.
Article
en En
| MEDLINE
| ID: mdl-34461096
ABSTRACT
Lack of simple and robust methods to determine complement activation in human serum induced by antigen-antibody complexes is a major hurdle for monitoring therapeutic antibody drug quality and stability. Dezamizumab is a humanized IgG1 monoclonal antibody that binds to serum amyloid P component (SAP) for potential treatment of systemic amyloidosis. The mechanism of action of Dezamizumab includes the binding of SAP, complement activation through classical pathway, and phagocytosis; however, the steps in this process cannot be easily monitored. We developed two novel methods to determine Dezamizumab-SAP complex-induced complement activation. Complement component 3 (C3) depletion was detected by homogeneous time-resolved fluorescence (HTRF), and C3a desArg fragment, formed after the cleavage of C3 to yield C3a followed by removal of its C-terminal arginine residue, was determined using Meso Scale Discovery (MSD) technology. We found that the presence of both Dezamizumab and SAP was required for complement activation via both methods. The optimal molar ratio of DezamizumabSAP was 61 in order to obtain maximal complement activation. The relative potency from both methods showed a good correlation to Dezamizumab-SAP-dependent complement component 1q (C1q) binding activity in Dezamizumab thermal-stressed samples. Both SAP and C1q binding, as determined by surface plasmon resonance and the two complement activation potency methods described here, reflect the mechanism of action of Dezamizumab. We conclude that these methods can be used to monitor Dezamizumab quality for drug release and stability testing, and the novel potency methods reported here can be potentially used to evaluate complement activity induced by other antigen-antibody complexes.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Proteínas del Sistema Complemento
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Inmunoglobulina G
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Componente Amiloide P Sérico
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Activación de Complemento
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Resonancia por Plasmón de Superficie
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Anticuerpos Monoclonales
Límite:
Humans
Idioma:
En
Año:
2021
Tipo del documento:
Article