MultiTEP platform–based DNA vaccines for alpha-synucleinopathies: preclinical evaluation of immunogenicity and therapeutic potency

Abstract

We have previously demonstrated that anti-Aβ DNA vaccine (AV-1959D) based on our proprietary MultiTEP platform technology is extremely immunogenic in mice, rabbits, and monkeys. Importantly, MultiTEP platform enables development of vaccines targeting pathological molecules involved in various neurodegenerative disorders. Taking advantage of the universality of MultiTEP platform, we developed DNA vaccines targeting three B cell epitopes (aa85–99, aa109–126, aa126–140) of human alpha-Synuclein (hα-Syn) separately, or all three epitopes simultaneously. All four DNA vaccines (i) generate high titers of anti-hα-Syn antibodies; (ii) induce robust MultiTEP-specific Th cell responses without activation of potentially detrimental autoreactive anti-hα-Syn Th cells. Generated antibodies recognize misfolded hα-Syn produced by neuroblastoma cells, hα-Syn in the brain tissues of transgenic mouse strains and in the brain tissues of Dementia with Lewy Bodies (DLB) cases. Based on these results, the most promising vaccine targeting three B cell epitopes of hα-Syn simultaneously (PV-1950D) has been chosen for ongoing pre-clinical assessment in mouse models of hα-Syn with the aim to translate it to the human clinical trials.

Testing a MultiTEP-based combination vaccine to reduce Aβ and tau pathology in Tau22/5xFAD bigenic mice

“…Importantly, this universal MultiTEP vaccine platform is designed to provide a broad coverage of human MHC class II polymorphism by utilizing a wide array of tetanus toxin, hepatitis B, and influenza Th epitopes incorporated into the MultiTEP platform [26]. These foreign Th epitopes incorporated into the MultiTEP platform are very immunogenic in mice of different haplotypes, in rabbits, and in monkeys with highly polymorphic MHC class II genes [14, 22, 26, 41, 42]. A growing amount of evidence suggests that prophylactic vaccination delivered prior to clinical symptoms may be needed to prevent the development of AD fully.…”

A protein microarray-based in vitro transglutaminase assay platform for epitope mapping and immunogen design: implication for transglutaminase-mediated immunodominant determination

“…To map the crosslinking sites for the development of immunotherapies targeting the pathogenic aggregates, we designed a protein microarray-based in vitro TG2 assay platform and confirmed its efficacy by identifying the TG2 modification sites in superoxide dismutase 1 and alpha-synuclein. Interestingly, the TG2 modification motifs in alpha-synuclein closely match the antisera epitope sequences of animals immunized with the full length alpha-synuclein 60,61 , implying an endogenous role of TG2 modification in the protein's antigen determination. Indeed, the TG2 crosslinking, which results in ubiquitination prevention 62 and proteolytic resistance, could be a crucial prerequisite for an antigen peptide's proteasomal 63,64 or lysosomal 65 survival in antigen processing.…”

“…To map the crosslinking sites for the development of immunotherapies targeting the pathogenic aggregates, we designed a protein microarray-based in vitro TG2 assay platform and confirmed its efficacy by identifying the primary TG2 modification sites in superoxide dismutase 1 and alpha-synuclein. Interestingly, the TG2 modification motif in alpha-synuclein directly corresponds to the antisera epitope of animals immunized with the full length alpha-synuclein 60, 61 , implying an endogenous role of TG2 modification in the protein’s antigen determination. Amyotrophic lateral sclerosis is associated with SOD1 mutations that may greatly alter the protein’s reactivity with transglutaminase and thereby contribute to the protein aggregation.…”

Efficacy and immunogenicity of MultiTEP-based DNA vaccines targeting human α-synuclein: prelude for IND enabling studies

“…More specifically, we showed that vaccinations of hα-Syn Tg D line mice, mimicking certain aspects of PD/DLB with full-length recombinant hα-Syn protein, induced therapeutically potent antibodies capable of reducing intracellular toxic hα-Syn aggregates. Importantly, we identified four B-cell epitopes spanning amino acids 85–99, 109–123, 112–126, and 126–138 of hα-Syn 20 , 22 , 30 that have been used for the generation of vaccines and monoclonal antibodies (mAb) for the treatment of PD, DLB, and MSA. For example, it was reported that administration of mAb specific to aa118–126 of hα-Syn (9A4) reduced neurological deficits and improved behavior of Tg D line (aka PDGFβ-α-Syn) mice 31 , while two other mAb (1H7 and 5D12) mitigated neurodegeneration in the line 61 mice (aka Thy1-α-Syn) 32 .…”