Abstract: An expression vector is provided for production of human alpha-synuclein (?S) protein or a conservative variant thereof that exhibits a decreased tendency to self-aggregate in an ?S seed amplification assay (SAA). The expression vector comprises a nucleic acid sequence coding for human ?S protein or a conservative variant, the nucleic acid sequence comprising codons that have been optimized to produce human ?S protein or a conservative variant when expressed by a host cell such as E. Coli. The codons have been optimized to avoid amino acid misincorporation in the expressed protein. Methods for purification of the expressed protein are also provided.

Abstract: A method is provided for determining the presence of soluble, misfolded ?-synuclein protein in a biological sample. The method comprises contacting the biological sample with a pre-incubation mixture, the pre-incubation mixture comprising: a monomeric ?-synuclein protein; a buffer composition; a salt; and an indicator, to form an incubation mixture. An incubation cycle is conducted on the incubation mixture in the presence of either a silicon nitride bead or a borosilicate glass bead having a diameter of from about 1 mm to about 5 mm. The method further comprises determining if a detectable amount of misfolded ?-synuclein aggregate is present in the biological sample.

Abstract: An expression vector is provided for production of human alpha-synuclein (?S) protein or a conservative variant thereof that exhibits a decreased tendency to self-aggregate in an ?S seed amplification assay (SAA). The expression vector comprises a nucleic acid sequence coding for human ?S protein or a conservative variant, the nucleic acid sequence comprising codons that have been optimized to produce human ?S protein or a conservative variant when expressed by a host cell such as E. coli. The codons have been optimized to avoid amino acid misincorporation in the expressed protein. Methods for purification of the expressed protein are also provided.

Abstract: A method is provided for determining the presence of soluble, misfolded ?-synuclein protein in a biological sample. The method comprises contacting the biological sample with a pre-incubation mixture, the pre-incubation mixture comprising: a monomeric ?-synuclein protein; a buffer composition; a salt; and an indicator, to form an incubation mixture. An incubation cycle is conducted on the incubation mixture in the presence of either a silicon nitride bead or a borosilicate glass bead having a diameter of from about 1 mm to about 5 mm. The method further comprises determining if a detectable amount of misfolded ?-synuclein aggregate is present in the biological sample.

Abstract: Methods and kits are provided for reproducible detection of misfolded aS aggregates in biological fluids and tissue that are less-invasively or non-invasively obtained compared to cerebrospinal fluid, such as skin, olfactory mucosa, saliva, and blood or blood parts.

Abstract: Inert matrices for use with a-synuclein seed amplification assays (“?S-SAA”s) are provided. The inert matrices accurately reflect the absence of misfolded ?S protein when used as a negative control, in the form of no, perceptively low, or delayed ?S substrate self-aggregation, yet will readily permit aggregation of the ?S substrate with seeds when used as a positive control. The inert matrices may be used to screen for ?S-SAA reagent competence. The inert matrices may be used to dilute samples taken from peripheral biological matrices. Finally, the inert matrices may be used as a diluent for serial dilutions of ?S-SAA samples, to enable semi-quantitative versions of ?S-SAAs.

Abstract: An expression vector is provided for production of human alpha-synuclein (?S) protein or a conservative variant thereof that exhibits a decreased tendency to self-aggregate in an ?S seed amplification assay (SAA). The expression vector comprises a nucleic acid sequence coding for human ?S protein or a conservative variant, the nucleic acid sequence comprising codons that have been optimized to produce human ?S protein or a conservative variant when expressed by a host cell such as E. Coli. The codons have been optimized to avoid amino acid misincorporation in the expressed protein. Methods for purification of the expressed protein are also provided.

Abstract: An expression vector is provided for production of human alpha-synuclein (?S) protein or a conservative variant thereof that exhibits a decreased tendency to self-aggregate in an ?S seed amplification assay (SAA). The expression vector comprises a nucleic acid sequence coding for human ?S protein or a conservative variant, the nucleic acid sequence comprising codons that have been optimized to produce human ?S protein or a conservative variant when expressed by a host cell such as E. coli. The codons have been optimized to avoid amino acid misincorporation in the expressed protein. Methods for purification of the expressed protein are also provided.

Abstract: A method is provided for determining the presence of soluble, misfolded ?-synuclein protein in a biological sample. The method comprises contacting the biological sample with a pre-incubation mixture, the pre-incubation mixture comprising: a monomeric ?-synuclein protein; a buffer composition; a salt; and an indicator, to form an incubation mixture. An incubation cycle is conducted on the incubation mixture in the presence of either a silicon nitride bead or a borosilicate glass bead having a diameter of from about 1 mm to about 5 mm. The method further comprises determining if a detectable amount of misfolded ?-synuclein aggregate is present in the biological sample.

Abstract: An expression vector is provided for production of human alpha-synuclein (?S) protein or a conservative variant thereof that exhibits a decreased tendency to self-aggregate in an ?S seed amplification assay (SAA). The expression vector comprises a nucleic acid sequence coding for human ?S protein or a conservative variant, the nucleic acid sequence comprising codons that have been optimized to produce human ?S protein or a conservative variant when expressed by a host cell such as E. coli. The codons have been optimized to avoid amino acid misincorporation in the expressed protein. Methods for purification of the expressed protein are also provided.

Abstract: A method is provided for determining the presence of soluble, misfolded ?-synuclein protein in a biological sample. The method comprises contacting the biological sample with a pre-incubation mixture, the pre-incubation mixture comprising: a monomeric ?-synuclein protein; a buffer composition; a salt; and an indicator, to form an incubation mixture. An incubation cycle is conducted on the incubation mixture in the presence of either a silicon nitride bead or a borosilicate glass bead having a diameter of from about 1 mm to about 5 mm. The method further comprises determining if a detectable amount of misfolded ?-synuclein aggregate is present in the biological sample.

Abstract: A method is provided for distinguishing between and/or diagnosing Parkinson's disease (PD) or multiple system atrophy (MSA) in a subject who is exhibiting symptoms associated with both PD and MSA. The method comprises: (A) contacting a biological sample obtained from the subject and comprising soluble, misfolded alpha-synuclein (?S) protein with a pre-incubation mixture comprising a monomeric ?S substrate and an indicator to form an incubation mixture; (B) conducting an incubation cycle two or more times on the incubation mixture to form misfolded ?S aggregates; (C) subjecting the incubation mixture to excitation and detecting via indicator fluorescence emission the misfolded ?S aggregates; and (D) diagnosing the subject has having PD or MSA depending on the fluorescence emission intensity. In some aspects, the incubation cycles are conducted in the presence of a bead.

Abstract: A method is provided for distinguishing between and/or diagnosing Parkinson's disease (PD) or multiple system atrophy (MSA) in a subject who is exhibiting symptoms associated with both PD and MSA. The method comprises: (A) contacting a biological sample obtained from the subject and comprising soluble, misfolded alpha-synuclein (?S) protein with a pre-incubation mixture comprising a monomeric ?S substrate and an indicator to form an incubation mixture; (B) conducting an incubation cycle two or more times on the incubation mixture to form misfolded ?S aggregates; (C) subjecting the incubation mixture to excitation and detecting via indicator fluorescence emission the misfolded ?S aggregates; and (D) diagnosing the subject has having PD or MSA depending on the fluorescence emission intensity. In some aspects, the incubation cycles are conducted in the presence of a bead.

Abstract: A method is provided for determining the presence of soluble, misfolded ?-synuclein protein in a biological sample. The method comprises contacting the biological sample with a pre-incubation mixture, the pre-incubation mixture comprising: a monomeric ?-synuclein protein; a buffer composition; a salt; and an indicator, to form an incubation mixture. An incubation cycle is conducted on the incubation mixture in the presence of either a silicon nitride bead or a borosilicate glass bead having a diameter of from about 1 mm to about 5 mm. The method further comprises determining if a detectable amount of misfolded ?-synuclein aggregate is present in the biological sample.

Abstract: Methods and kits for evaluating a subject for a brain injury are described. The method may include providing at least one biological sample from the subject having or suspected of having the brain injury. The method may include conducting one or more amplification reactions, including contacting a portion of the biological sample with a monomeric, folded tau protein to form an incubation mixture. Each amplification reaction may include determining a presence or amount of the misfolded tau protein in the biological sample according to the amplified portion of the misfolded tau protein. Methods for evaluating the risk of neurodegenerative disease or disorder in a subject having suffered from brain injury are also described.