Abstract
Complement C5 is the target of the monoclonal antibody eculizumab, used in complement dysregulating disorders, like the rare disease Paroxysmal Nocturnal Hemoglobinuria (PNH). PNH is an acquired hematopoietic stem cell condition characterized by aberrant destruction of erythrocytes, chronic hemolytic anemia, and thromboembolism propensity. C5 is a protein component of the complement system which is part of the immune system of the body and plays a prominent role in the destruction of red blood cells, misidentifying them as a threat. This work describes the application of molecular dynamics simulations to the study of the underlying interactions between complement C5 and eculizumab. This study also reveals the importance of single nucleotide polymorphisms on C5 protein concerning the effective inhibition of the mAB, involving the mechanistic events taking place at the interface spots of the complex. The predicted conformational change in the C5 Arg885/His/Cys mutation has implications on the protein’s interaction with eculizumab, compromising their compatibility. The acquired insights into the conformational changes, dynamics, flexibility, and interactions shed light on the knowledge of the function of this biomolecule providing answers about the poor response to the treatment in PNH patient carriers of the mutations. By investigating the intricate dynamics, significant connections between C5 and eculizumab can be uncovered. Such insights may aid in the creation of novel compounds or lead to the enhancement of eculizumab’s efficacy.
Communicated by Ramaswamy H. Sarma
Authors’ contributions
Data curation, investigation, methodology, VPP and SFS; Formal analysis, VPP and SFS; Resources, SFS; Supervision, SFS and MV; Validation, VPP and SFS; Visualization, VPP and SFS; Writing original draft preparation, VPP and SFS; Writing, review, and editing, VPP, SFS, MV and CP; All authors have read and agreed to the published version of the manuscript.
Availability of data and material
Available upon reasonable request.
Disclosure statement
The authors report no conflict of interest.