African-Americans With Multiple Sclerosis Have a Higher Proportion of B-Cell Lineage Cells in Their Cerebrospinal Fluid (CSF) Than White Patients (P9-3.010)

Abstract

<h3>Objective:</h3> To compare proportions of B-cell lineage CD19+ and CD20+ cells in CSF of African-Americans (AA) and White (W) patients with MS. <h3>Background:</h3> Compared to W patients, AA patients with MS are more likely to have oligoclonal bands in CSF; have higher IgG index in CSF; and have higher circulating plasmablasts in blood. It is unknown whether the proportion of B-cells in CSF differs between AA and white patients in MS. <h3>Design/Methods:</h3> Demographics, disease-related information, and treatment history were retrospectively collected on patients with neurologist-diagnosed MS who self-identified as AA or W, received care at NYU MS Care Center, and underwent flow cytometry of CSF during diagnostic work-up. Lymphocyte subsets (B-lymphocytes, T-lymphocytes, NK cells), monocytes and plasma cells were analyzed with flow cytometry (BD FACSCanto™ and FACSCanto™ II Cell Analyzers). <h3>Results:</h3> 20 AA and 57 W MS patients fulfilled inclusion criteria. The groups had similar age at lumbar puncture, sex ratio, CSF cell counts, protein and glucose CSF concentrations, and oligoclonal band number. IgG index was higher in AA compared to W (<i>1.08 v 0.87, p=0.044</i>). With respect to mononuclear cell counts in CSF, AA had higher proportions of CD19+ (<i>5.45% AA v. 2.27% W, p=0.0061</i>) and CD20+ (<i>5.00% AA v. 1.95% W, p=0.0046</i>) cells, but did not significantly differ in proportion of CD4+, CD8+, CD38+ bright B-cells, NK cells and monocytes. Sensitivity analyses that excluded all patients on disease-modifying therapy at the time of lumbar puncture (n=8) yielded similar conclusions. <h3>Conclusions:</h3> B-cells are overrepresented in the CSF of African American patients with MS relative to Whites. Whether this finding bears on the increased severity of MS disease course in AA patients warrants investigation. <b>Disclosure:</b> Mr. Xue has nothing to disclose. Dr. Arbini has nothing to disclose. Mr. Melton has received personal compensation for serving as an employee of Janssen Pharmaceuticals. Dr. Kister has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Genentech-Roche. The institution of Dr. Kister has received research support from Genentech. Dr. Kister has received publishing royalties from a publication relating to health care.