Identifying the Pathological Domain of Alpha- Synuclein as a Therapeutic for Parkinson‚Äôs Disease
Authors: Yuzhu Hong
Ning Shen
Chuanhai Cao
Haiqiang Yang
Xiaoyang Lin
Ge Song
Breanna Brown
Jianfeng Cai
Journal: International Journal of Molecular Sciences (2019)
Discipline: CHEMISTRY
Keywords: Alpha synuclein; Parkinson‚Äôs disease; antibody; antigenicity; epitope
Affiliations: Department of Chemistry, University of South Florida, Tampa, FL 33612, USA. ., Department of Surgery of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin 300193, China. ., Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL 33612, USA. ., Department of Neurology, College of Medicine, University of South Florida, Tampa, FL 33612, USA. .

Abstract:  Alpha-synuclein is considered the major pathological protein associated with Parkinson's disease, but there is still no effective immunotherapy which targets alpha-synuclein. In order to create a safer and more effective therapy against PD, we are targeting an epitope of alpha-synuclein rather than full-length alpha-synuclein. We have selected several antigenic domains (B-cell epitope) through antigenicity prediction, and also made several recombinant protein fragments from alpha-synuclein upon antigenicity prediction in an E. coli system. We then tested the function of each of the peptides and recombinant fragments in aggregation, their toxicity and antigenicity. We have discovered that the full-length recombinant (aa1-140) can aggregate into oligomers or even fibrils, and fragment aa15-65 can promote the aggregation of aa1-140. It is worth noting that it not only promotes whole protein aggregation, but also self-aggregates as seen by western blotting and silver staining assays. We have tested all candidates on primary neurons for their toxicity and discovered that aa15-65 is the most toxic domain compared to all other fragments. The antibody targeting this domain also showed both anti-aggregation activity and some therapeutic effect. Therefore, we believe that we have identified the most potent therapeutic domain of alpha synuclein as a therapeutic target. 

Retracted: No

PubPeer comments:
 Could the authors please provide the original WB images for this manuscript? At least FIg.2 and Fig.4 contain spliced bands as indicated below (false colors and higher contrast) Fig.2:  Fig.4:  , 
 Hi, Heterochasta Lasioplac! Here s all the original film for fig 2 and fig 4. For fig 2, they were supposed to be detected in different films and gels, since they all using different antibodies to detect. I actually donu2019t want people to think they are from one film that s why I mark the antibodies. Sorry for the confusion. For Fig 4, they are do came from one film. I just sometimes run more samples on one gel. Since they are not related to this article so I cut them off. I could promise you all the data was been confirmed by multiple trials. Best, Ning  , 
 Dear Ning, Thank you for your response and clarifying this by posting the original blots, and I got your point. I would advise for future publications to leave a visible line between such blot pieces, to avoid such confusion. , 
 #3 Thank you so much for your advice! And I will do so in the future. Bestuff0c Ning , 
 Could the authors comment on the apparent reuse of two lanes in Figure 4 and 9? Is this another case where splicing was not indicated? ***  , 
 Hi! Thanks for your comment! Those two figures do came from the same membrane. Theyu2019ve been split to explain different stories. And thatu2019s why they share the same control lanes. I attached the original data here with the different exposure times (the erased lane was not related to this article). In my original notes, you could also find that in figure 4-b, lane 4 and lane 5 was been switched to keep the consistency with other panels in this figure 4. Sorry for the confusion and thank you so much for reading our article! Always Best, Ning , 
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