Diminished Th17 (not Th1) responses underlie multiple sclerosis disease abrogation after hematopoietic stem cell transplantation. Issue 3 (5th March 2013)

• Record Type: Journal Article
• Authors: Darlington, Peter J.; Touil, Tarik; Doucet, Jean‐Sebastien; Gaucher, Denis; Zeidan, Joumana; Gauchat, Dominique; Corsini, Rachel; Kim, Ho Jin; Duddy, Martin; Jalili, Farzaneh; Arbour, Nathalie; Kebir, Hania; Chen, Jacqueline; Arnold, Douglas L.; Bowman, Marjorie; Antel, Jack; Prat, Alexandre; Freedman, Mark S.; Atkins, Harold; Sekaly, Rafick; Cheynier, Remi; Bar‐Or, Amit
• Is Part Of: Annals of neurology. Volume 73:Issue 3(2013:Mar.)
• Page Start: 341
• Page End: 354
• Publication Date: 2013-03-05
• Subjects: Neurology -- Periodicals; Pediatric neurology -- Periodicals; Nervous system -- Surgery -- Periodicals; 616.8
• DOI: 10.1002/ana.23784
• Languages: English
• ISSNs: 0364-5134

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="ana23784-sec-0001" sec-type="section"> <title>Objective</title> <p>To define changes in phenotype and functional responses of reconstituting T cells in patients with aggressive multiple sclerosis (MS) treated with ablative chemotherapy and autologous hematopoietic stem cell transplantation (HSCT).</p> </sec> <sec id="ana23784-sec-0002" sec-type="section"> <title>Methods</title> <p>Clinical and brain magnetic resonance imaging measures of disease activity were monitored serially in patients participating in the Canadian MS HSCT Study. Reconstitution kinetics of immune‐cell subsets were determined by flow cytometry, whereas thymic function was assessed using T‐cell receptor excision circle analyses as well as flow cytometry measurements of CD31<sup>+</sup> recent thymic emigrants (RTEs). Functional assays were performed to track central nervous system–autoreactive antigen‐specific T‐cell responses, and the relative capacity to generate Th1, Th17, or Th1/17 T‐cell responses.</p> </sec> <sec id="ana23784-sec-0003" sec-type="section"> <title>Results</title> <p>Complete abrogation of new clinical relapses and new focal inflammatory brain lesions throughout the 2 years of immune monitoring following treatment was associated with sustained decrease in naive T cells, in spite of restoration of both thymic function and release of RTEs during reconstitution. Re‐emergence as well as in vivo expansion of autoreactive T cells to multiple myelin targets was evident in all patients studied. The reconstituted myelin‐specific T cells exhibited the same Th1 and Th2 responses as preablation myelin‐reactive T cells. In contrast, the post‐therapy T‐cell repertoire exhibited a significantly diminished capacity for Th17 responses.</p> </sec> <sec id="ana23784-sec-0004" sec-type="section"> <title>Interpretation</title> <p>Our results indicate that diminished Th17 and Th1/17 responses, rather than Th1 responses, are particularly relevant to the abrogation of new relapsing disease activity observed in this cohort of patients with aggressive MS following chemoablation and HSCT. ANN NEUROL 2013;73:341–354</p> </sec> </abstract>