CNS B cell infiltration in tumefactive anti-myelin oligodendrocyte glycoprotein antibody-associated disease.

Background: Few studies have examined B cells among patients with anti-myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD), including brain pathology.

Objective: To describe cases of tumefactive MOGAD with B-cell dominant central nervous system (CNS) infiltration.

Methods: In this study, we reviewed three cases with clinical and brain histopathological features with tumefactive MOGAD.

The real-world impact of biologics for NMOSD: A retrospective single-center study compared with natural course and conventional treatments in Japanese.

Background: Neuromyelitis optica spectrum disorder (NMOSD), a central nervous system inflammatory disease associated with aquaporin-4 immunoglobulin G (AQP4-IgG), is conventionally treated with oral steroids and immunosuppressants (IS) in Japan. Several biologics which show great efficacy in the clinical trials have been developed recently. However, studies on their efficacy, especially those comparing them with conventional treatments in real-world situations are lacking.

Clinical practice guidelines for multiple sclerosis, neuromyelitis optica spectrum disorder, and myelin oligodendrocyte glycoprotein antibody-associated disease 2023 in Japan.

Background: The previous Japanese clinical practice guidelines for multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) were published in 2017. Recently, for the first time in 6 years, the MS and NMOSD guideline development committee revised the Japanese guidelines for MS, NMOSD, and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD).

Methods: The committee utilized the Grading of Recommendations Assessment, Development, and Evaluation system based on the "Minds Handbook for Clinical Practice Guideline Development 2020 Ver.

Different Complement Activation Patterns Following C5 Cleavage in MOGAD and AQP4-IgG+NMOSD.

Objectives: In myelin oligodendrocyte glycoprotein IgG-associated disease (MOGAD) and aquaporin-4 IgG+ neuromyelitis optica spectrum disorder (AQP4+NMOSD), the autoantibodies are mainly composed of IgG1, and complement-dependent cytotoxicity is a primary pathomechanism in AQP4+NMOSD. We aimed to evaluate the CSF complement activation in MOGAD.

Methods: CSF-C3a, CSF-C4a, CSF-C5a, and CSF-C5b-9 levels during the acute phase before treatment in patients with MOGAD (n = 12), AQP4+NMOSD (n = 11), multiple sclerosis (MS) (n = 5), and noninflammatory neurologic disease (n = 2) were measured.

Humanized-Aquaporin-4-Expressing Rat Created by Gene-Editing Technology and Its Use to Clarify the Pathology of Neuromyelitis Optica Spectrum Disorder.

Conventional rodent neuromyelitis optica spectrum disorder (NMOSD) models using patient-derived immunoglobulin G (IgG) are potentially affected by the differences between the human and rodent aquaporin-4 (AQP4) extracellular domains (ECDs). We hypothesized that the humanization of AQP4 ECDs would make the rodent model lesions closer to human NMOSD pathology. Humanized-AQP4-expressing (hAQP4) rats were generated using genome-editing technology, and the human AQP4-specific monoclonal antibody (mAb) or six patient-derived IgGs were introduced intraperitoneally into hAQP4 rats and wild-type Lewis (WT) rats after immunization with myelin basic protein and complete Freund's adjuvant.