biostudies-literatureMikulka CRHHS | National Institutes of HealthBioMarin PharmaceuticalNIA NIH HHSNINDS NIH HHS9032-9041https://www.ebi.ac.uk/biostudies/studies/S-EPMC7183170biostudies-literatureUnknown117(16)Lysosomal storage diseases (LSDs) are typically caused by a deficiency in a soluble acid hydrolase and are characterized by the accumulation of undegraded substrates in the lysosome. Determining the role of specific cell types in the pathogenesis of LSDs is a major challenge due to the secretion and subsequent uptake of lysosomal hydrolases by adjacent cells, often referred to as "cross-correction." Here we create and validate a conditional mouse model for cell-autonomous expression of galactocerebrosidase (GALC), the lysosomal enzyme deficient in Krabbe disease. We show that lysosomal membrane-tethered GALC (GALCLAMP1) retains enzyme activity, is able to cleave galactosylsphingosine, and is unable to cross-correct. Ubiquitous expression of GALCLAMP1 fully rescues the phenotype of the GALCProceedings of the National Academy of Sciences of the United States of AmericaCell-autonomous expression of the acid hydrolase galactocerebrosidase.PMC71831701NS100779R01 NS100779R01 NS087632R01 AG013730RF1 AG013730Benitez BAMilbrandt JLiu LMikulka CRStrickland ADearborn JTSands MSfalseCell-autonomous expression of the acid hydrolase galactocerebrosidase.Lysosomal storage diseases (LSDs) are typically caused by a deficiency in a soluble acid hydrolase and are characterized by the accumulation of undegraded substrates in the lysosome. Determining the role of specific cell types in the pathogenesis of LSDs is a major challenge due to the secretion and subsequent uptake of lysosomal hydrolases by adjacent cells, often referred to as "cross-correction." Here we create and validate a conditional mouse model for cell-autonomous expression of galactocerebrosidase (GALC), the lysosomal enzyme deficient in Krabbe disease. We show that lysosomal membrane-tethered GALC (GALCLAMP1) retains enzyme activity, is able to cleave galactosylsphingosine, and is unable to cross-correct. Ubiquitous expression of GALCLAMP1 fully rescues the phenotype of the GALC2020-01-01T00:00:00Z2020 Apr2025-06-01T12:02:28.887Z2025-06-01T12:02:28.887ZS-EPMC71831703225331910.1073/pnas.1917675117