Background: Ublituximab, a novel monoclonal antibody (mAb) targeting a unique epitope on the CD20 antigen, is glycoengineered for enhanced B-cell targeting through antibody-dependent cellular cytotoxicity (ADCC). Greater ADCC may allow lower doses and shorter infusion times versus other anti-CD20 mAbs. Objective: The objective was to determine optimal dose, infusion time, and activity of ublituximab in relapsing multiple sclerosis. Methods: This is a phase 2, placebo-controlled study. Patients received three ublituximab infusions (150 mg over 1–4 hours on day 1 and 450–600 mg over 1–3 hours on day 15 and week 24) in six dosing cohorts. The primary endpoint was B-cell depletion. Results: In all cohorts ( N = 48), median B-cell depletion was >99% by week 4, maintained at weeks 24 and 48. Most common adverse events (AEs) were infusion-related reactions (all grade 1–2), with no apparent increased incidence at shorter infusion times. There were no AE-related discontinuations. At weeks 24 and 48, no T1 gadolinium-enhancing lesions ( p = 0.003) and a 10.6% decrease in T2 lesion volume ( p = 0.002) were detected. The annualized relapse rate was 0.07; 93% remained relapse free on study. Overall, 74% of patients had no evidence of disease activity (NEDA). Conclusion: Ublituximab was safely infused as rapid as 1 hour, producing robust B-cell depletion and profound reductions in magnetic resonance imaging (MRI) activity and relapses.

Monoclonal antibodies to the matrix or E1 glycoprotein of mouse hepatitis virus (MHV) were tested for their ability to protect mice from a normally lethal challenge of MHV-4. Four antibodies were tested, and two of these, J.1.3 and J.3.9, were protective. Protection did not correlate with virus neutralization in vitro, antibody isotype, recognition of a unique E1 antigenic site, or dependence on complement in vivo. Survival from acute encephalitis was followed by subacute demyelination, as has been shown with protection mediated by neutralizing monoclonal antibodies against the major glycoprotein, E2. These results demonstrate that antibodies which are specific for a viral matrix protein are able to alter the course of disease.

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Clearance of the neurotropic JHM strain of mouse hepatitis virus from the central nervous system was examined by the transfer of spleen cells from immunized donors. A T cell with the surface phenotype of Thy1.2+ CD4+ CD8- asialo-GM1+ Mac-1- was found to be necessary for viral clearance. The surface phenotype and adherence to nylon wool suggest that these cells are activated helper-inducer T cells. Adoptive transfer to congenic histocompatibility strains demonstrated the necessity for compatibility at the D locus of the major histocompatibility complex. The expression of the CD4 surface marker and the requirement for major histocompatibility complex class I were further studied by the transfer of cells to recipients treated with anti-CD4 or anti-CD8 monoclonal antibodies. Treatment of recipients with either the anti-CD8 or the anti-CD4 antibodies inhibited virus clearance from the central nervous system. This suggests that the CD4+ cell acts as a helper and that virus is cleared from the central nervous system. This suggests that the CD4+ cell acts as a helper and that virus is cleared from the central nervous system by CD8+ cells that recognize viral antigen in the context of the H-2Db gene product.

We performed nocturnal polysomnography on 11 children with autism who had symptoms of disrupted sleep and nocturnal awakenings. We identified rapid eye movement (REM) sleep behavior disorder in 5 of these 11 patients. Since REM sleep behavior disorder typically affects elderly males with neurodegenerative diseases, the identification of this phenomenon in autistic children could have profound implications for our understanding of the neurochemical and neurophysiologic bases of autism. Further, accurate diagnosis of REM sleep behavior disorder would enable specific treatment with clonazepam and help the family and the child consolidate sleep and improve daytime performance.

Multiple sclerosis (MS) is a demyelinating disease of the central nervous system, thought to be mediated by myelin-specific CD4+ T cells. However, B cell depletion has proven to be an effective therapy for MS, but the mechanism is not well understood. This study was designed to determine how B cell depletion changes lymphocyte profiles. During a phase IIa clinical trial with ublituximab, a novel CD20 antibody, blood was collected from 48 MS patients at 11 time points over 24 weeks and the lymphocyte profiles were analyzed by flow cytometry. The percentage of naïve CD4+ and CD8+ T cells increased, while the percentage of both effector and central memory T cells declined. CD4+ Th1 effector cells decreased, while there was a significant increase in CD4+ regulatory T cells. The depletion of B cells had a favorable shift in the lymphocyte landscape, reducing the number of naïve T cells becoming activated and transitioning to memory T cells. The ratio of Th1 cells to CD4+ regulatory T cells declined, suggesting that immune regulation was being restored. These data suggest that loss of B cells as antigen presenting cells is a major mechanism of action for the beneficial effects of CD20 antibody therapy in MS.

Stroke in childhood is often catastrophic, with major sequelae. We report the first successful use of recombinant tissue plasminogen activator for arterial stroke in a child. The patient recovered with no neurologic deficit.

Lubag (X-linked dystonia-parkinsonism) has been considered a sex-linked recessive trait and has been mapped to the pericentromeric region of the X chromosome. We studied a 54-year-old man with lubag and two of his female first cousins. Genetic typing was carried out using X chromosome markers. Fluorodopa PET was performed on the man and one of the women. The man had moderately severe parkinsonism and dystonia. A 61-year-old female first cousin had mild left-sided dystonia and her 54-year-old sister had mild generalized chorea. Genetic typing data revealed that all three inherited an X chromosome with marker alleles strongly associated with lubag. Cytologic analysis did not reveal evidence of X chromosomal deletion. Fluorodopa PET in both the man and one affected cousin revealed reduced striatal uptake rate constants consistent with nigrostriatal involvement. These observations suggest that lubag may be a codominant disorder and that it is possible for women to be affected.