Cerebrospinal Fluid Biomarkers Associated with Intrathecal Cell Therapy in Patients with Progressive Multiple Sclerosis (P1-3.001)

Abstract

<h3>Objective:</h3> To identify cerebrospinal fluid (CSF) biomarkers of clinical response to intrathecal (IT) mesenchymal stem cell-neural progenitor (MSC-NP) treatment in patients with progressive multiple sclerosis (MS). <h3>Background:</h3> MSC-NPs are a bone marrow-derived population of cells with trophic and immunomodulatory properties with therapeutic potential in MS. A phase II randomized, double-blind, placebo-controlled clinical trial was performed to investigate whether multiple intrathecal (IT) injections of autologous MSC-NPs was associated with clinical efficacy. Study subjects received either 6 IT injections of autologous MSC-NPs or 6 placebo injections spaced 2 months apart. In the crossover study design, subjects treated with placebo in the first year were treated with MSC-NPs in the second year, and vice versa. Safety and clinical efficacy will be reported elsewhere. <h3>Design/Methods:</h3> For biomarker discovery, CSF was collected from 36 study subjects at the time of their first and sixth IT-MSC-NP treatment reflecting pre-treatment and post-treatment timepoints, respectively. CSF supernatants were analyzed using SOMAScan multiplex proteomic assay. Differentially expressed proteins were identified using a multivariate linear mixed effect model. Biomarkers were validated using ELISA/Luminex assays. Treatment responders were defined by improvement in any of the following outcomes: EDSS, timed 25-foot walk, 9-hole peg test, 6-minute walk test, or muscle strength. <h3>Results:</h3> Proteomic analysis of CSF identified matrix metalloproteinase-9 (MMP-9), complement C3a and the chemokine CCL2 as potential biomarkers of IT-MSC-NP treatment. MMP-9 was significantly increased post-treatment and was observed independent of clinical response. Relative concentration of C3a, C3 and C3b were decreased post-treatment and subgroup analysis demonstrated significance only in the responder group. CCL2 was significantly decreased post-treatment with higher significance associated with clinical response. Decreased CCL2 was validated in an independent cohort of patients treated with IT-MSC-NPs. <h3>Conclusions:</h3> These results identify multiple CSF biomarkers of IT-MSC-NP treatment that may correlate with therapeutic response to this novel cell therapy in MS. <b>Disclosure:</b> Miss Kizilbash has nothing to disclose. Ms. Carlson has nothing to disclose. Violaine K. Harris, PhD has nothing to disclose. Dr. Sadiq has nothing to disclose.