(A) Highest reciprocal dilution at which serum antibodies to rAAVrh74 capsid protein could be detected in one untreated GRMD dog (0 dose), four different GRMD dogs treated with low dose of rAAVrh74.MHCK7.GALGT2 (2x1014vg/kg), and in one dog treated with high dose of rAAVrh74.MHCK7.GALGT2 (6x1014vg/kg). (B) Highest reciprocal dilution at which serum antibodies could be identified to rAAV1, rAAV2, rAAV6, rAAV8, or rAAV9 capsid protein after treatment with rAAVrh74.MHCK7.GALGT2. (C) Interferon gamma (IFN-g) expressing cells were quantified in ELISpot assays of peripheral blood mononuclear cells (PBMCs) taken from GRMD dogs at 3 months of age (baseline, pretreatment) and at 45 or 90 days after treatment with rAAVrh74.MHCK7.GALGT2. Positive ELISpots to identify activated T cells were measured in response to 1 of 3 overlapping peptide pools made against the rAAVrh74 capsid protein and to 1 of 2 overlapping peptide pools made against the GALGT2 protein. ELISpot scores of 50 or more (line) are considered positive.