Methods for measuring the potency of AADC viral vectors

A method for measuring aromatic L-amino acid decarboxylase (AADC) viral vector potency, comprising:

• (a) providing an adeno-associated virus (AAV) formulation comprising an AADC viral vector, wherein the AADC viral vector is an AAV that comprises a polynucleotide encoding one or more AADC polypeptides;
• (b) contacting the AAV formulation with a cell under conditions that result in the cell producing one or more AADC polypeptides from the polynucleotide;
• (c) lysing the cell to form a first cell lysate comprising at least a portion of the AADC polypeptides;
• (d) determining the potency of the AADC viral vector by:
• (i) adding L-3,4 dihydroxyphenylalanine (L-DOPA) to the first cell lysate under conditions that allow at least a portion of the AADC polypeptides in the first cell lysate to react with at least a portion of the L-DOPA to produce dopamine;
• (ii) measuring the amount of dopamine in the first cell lysate after the reaction between the AADC polypeptides and the L-DOPA;
• (iii) providing an AADC viral vector reference standard for dopamine production, wherein the AADC viral vector reference standard comprises a polynucleotide encoding one or more AADC polypeptides, and wherein the amount of dopamine produced by the AADC viral vector reference standard is determined by:
• adding L-DOPA to a second cell lysate that comprises at least a portion of the AADC polypeptides, wherein the AADC polypeptides in the second cell lysate are produced by cells transduced with the AADC viral vector reference standard;
• and
• measuring the amount of dopamine produced in the second cell lysate after the reaction between the AADC polypeptides and the L-DOPA;
• and
• (iv) comparing the amount of dopamine produced using the AADC viral vector to the AADC viral vector reference standard, such that an AADC Relative Potency of the AADC viral vector is measured.