Pompe disease is caused by a deficiency of acid α-glucosidase (GAA; EC, 3.2.1.20), and the infantile-onset form is rapidly fatal if left untreated. However, recombinant human GAA (rhGAA) enzyme replacement therapy (ERT) extends survival for infantile Pompe patients. Although cross-reactive immunologic material (CRIM)-negative patients, who lack detectable endogenous GAA, mount an immune response to rhGAA that renders the therapy ineffective, timely induction of immune tolerance in these patients may improve clinical outcomes. Previously, CRIM status has been determined by Western blot analysis in cultured skin fibroblasts, a process that can take a few weeks. We present a blood-based CRIM assay that can yield results within 48 to 72 h. Results from this assay have been confirmed by GAA Western blot analysis in fibroblasts or by GAA sequencing in a small number of Pompe disease patients. Rapid classification of CRIM status will assist in identifying the most effective treatment course and minimizing treatment delays in patients with infantile-onset Pompe disease.
Keywords: 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid; ACD; ACTB; Acid maltase deficiency; BSA; CRIM; Cross-reactive immunologic material; DTT; ECL; EDTA; ERT; GAA; Glycogen storage disease type II; HEPES; HRP; IL-2; IOPD; ITI; LDS; OD; PBMC; PBS; PVDF; Pompe disease; SDS; TBST; TBST with 5% nonfat milk; TBST-milk; acid α-glucosidase; bovine serum albumin; citrate dextrose-A; cross-reactive immunologic material; dithiothreitol; enhanced chemiluminescence; enzyme replacement therapy; ethylenediaminetetraacetic acid; horseradish peroxidase; immune tolerance induction; infantile-onset Pompe disease; interleukin-2; lithium dodecyl sulfate; optical density; peripheral blood mononuclear cell; phosphate-buffered saline; polyvinylidene difluoride; recombinant human GAA; rhGAA; sodium dodecyl sulfate; tris-buffered NaCl solution with Tween® 20; β-actin.
© 2013.