The Potential of β-Synuclein-Specific Regulatory T Cell Therapy as a Treatment for Progressive Multiple Sclerosis

Disease progression in multiple sclerosis (MS) is now known to affect many patients, even those not diagnosed with progressive subtypes. Progressive and neurodegenerative aspects of MS are poorly treated by currently available therapies. Research on new therapeutic options is needed to improve health outcomes in people with MS. This review highlights the potential for treatment using an engineered T cell receptor-regulatory T cell (TCR-Treg) therapy targeting the presynaptic protein beta-synuclein. Tregs respond to self-antigens presented on human leukocyte antigen (HLA) class II with anti-inflammatory and pro-neural healing effects, but this response is impaired in MS patients. Since the HLA-DRB1*15:01 allele is known to contribute to MS pathogenesis, a TCR specific to a known antigen presented on DRB1*15:01 can be transduced into Tregs to direct them to activate within the inflamed brain tissue. Beta-synuclein is released from neurons at a high level after neural damage, may be presented on HLA, enables homing of specific T cells to the grey matter, and is immunogenic in progressive MS patients. This review presents beta-synuclein as a disease-relevant antigen to target for therapeutic development.