C4A and Parkinson disease: Indeed, in the current study, C2, C3, as well as factor H and C-type lectin were found to be deimination candidates in rat plasma, both in shams and the pre-motor PD model, while C1q, factor B, C4, C8, C9, C4-binding protein, properdin, and collectin were only identified as deiminated in the pre-motor PD model.