Katsuhiko Kunitake

We report a case of unilateral relapsing primary CNS vasculitis (PCNSV) treated with Rituximab. A 52-year old man initially diagnosed as PCNSV by brain biopsy. He was treated with corticosteroids and no recurrence had been recognized for 4 years. However, after the reduction of corticosteroids to 9 ‍mg, PCNSV recurred many times only in the right hemisphere. Mycophenolate mofetil and cyclophosphamide were not effective. We diagnosed this patient as unilateral relapsing PCNSV (UR-PCNSV), which is resistant to treatment and repeatedly relapses unilaterally. After rituximab was introduced, there was no clinical recurrence and abnormal lesions on head MRI improved. We emphasize that rituximab is a good candidate drug for treating the UR-PCNSV.

Antisense oligonucleotide (ASO)-based exon skipping is a representative splice modulating therapy effective for Duchenne muscular dystrophy (DMD), a condition arising from dystrophin deficiency. For a valuable platform of evaluating exon-skipping efficacy, we previously reported a highly effective approach to convert CD90-positive human urine-derived cells (UDCs) into myotubes through the transduction of the MYOD1 gene. We anticipate that highly differentiated myotubes enable their utilization in various human muscle cell studies and a more predictive screening approach for the preclinical identification of promising ASOs at an earlier stage of the drug discovery process. Here, we describe protocols and tips for isolating UDCs, differentiating CD90-positive UDCs into myotubes, and evaluating the correction of DMD mRNA and protein levels in the myotubes after exon skipping.

Antisense oligonucleotide (ASO)-based exon skipping is a splice-modulating therapy effective for Duchenne muscular dystrophy (DMD) caused by dystrophin deficiency. Here, we present a protocol for evaluating exon skipping efficacy in MYOD1-transduced human urine-derived cells (MYOD1-UDCs) from patients. We describe steps for isolating UDCs, selecting CD90-positive cells, inducing myogenic differentiation, and assessing the restoration of DMD mRNA and proteins after exon skipping. This platform enhances the predictability of ASO screening, promoting early-stage drug discovery and translational research in DMD. For complete details on the use and execution of this protocol, please refer to Komaki et al.1.