title: Effects of rituximab on lymphocytes in multiple sclerosis and neuromyelitis optica.
abstract: OBJECTIVE
  To investigate the effect of rituximab, a B-cell targeted therapy that is used in the treatment of multiple sclerosis (MS) and neuromyelitis optica (NMO), on other immune cells such as CD4+ and CD8+ T-cells in patients with MS and NMO.
  
  
  METHODS
  This is a retrospective study of all patients with MS or NMO who received at least one rituximab infusion at the UCSF MS tertiary care center between May 2005 and July 2011.
  
  
  METHODS
  Linear mixed models were used to assess (a) how post-infusion cell counts changed over time compared to pre-infusion levels and one another; (b) whether the cell counts were different over multiple courses of rituximab; and (c) what was the dosing effect on the cell counts over time.
  
  
  RESULTS
  Rituximab initially reduced CD4+ (by 26%, p=0.0005) and CD8+ (by 22%, p=0.0006) T-cells, although these changes were only transient. Subsequent treatments with rituximab did not result in a significant drop in CD4+ or CD8+ T-cells. Changes in other cell types were also typically more marked after the first cycle of rituximab than after additional treatments. The total dose of rituximab received did not appear to have a significant effect.
  
  
  CONCLUSIONS
  Although transient, rituximab-induced decrease in CD4+ and CD8+ T-cells may increase the risk of infection in susceptible individuals.
authors: University of California, San Francisco, Department of Neurology, Box 3206, MS Center, 675 Nelson Rising Lane Suite 221, CA 94158, United States. Electronic address: Jennifer.graves@ucsf.edu.
authors: Jennifer
authors: J
authors: Graves
authors: University of California, San Francisco, Department of Neurology, Box 3206, MS Center, 675 Nelson Rising Lane Suite 221, CA 94158, United States. Electronic address: uxv5@case.edu.
authors: Uma
authors: U
authors: Vinayagasundaram
authors: University of California, San Francisco, Department of Neurology, Box 3206, MS Center, 675 Nelson Rising Lane Suite 221, CA 94158, United States. Electronic address: emowry1@jhmi.edu.
authors: Ellen M
authors: EM
authors: Mowry
authors: University of California, San Francisco, Department of Neurology, Box 3206, MS Center, 675 Nelson Rising Lane Suite 221, CA 94158, United States. Electronic address: imatthew@hamilton.edu.
authors: Ian R
authors: IR
authors: Matthews
authors: University of California, San Francisco, Department of Neurology, Box 3206, MS Center, 675 Nelson Rising Lane Suite 221, CA 94158, United States. Electronic address: marino@bgu.ac.il.
authors: Julia A
authors: JA
authors: Marino
authors: University of California, San Francisco, Department of Preventive & Restorative Dental Sciences, United States. Electronic address: jing.cheng@ucsf.edu.
authors: Jing
authors: J
authors: Cheng
authors: University of California, San Francisco, Department of Neurology, Box 3206, MS Center, 675 Nelson Rising Lane Suite 221, CA 94158, United States. Electronic address: emmanuelle.waubant@ucsf.edu.
authors: Emmanuelle
authors: E
authors: Waubant
keywords: Demyelinating diseases; Immunology; Monoclonal antibodies; Multiple sclerosis; Neuromyelitis optica; Rituximab