B cells against brain proteins during active MS

These papers were from a  fews years back but I have decided to post them as this paper looks for B cells that react to proteins within the brain. Not myelin proteins in particular. They simply look at a brain mush and find that the majority of people with MS make B cells that can recongnise the brain. These represent plasma cells/plasma blasts making antibody at the time of assays and the memory B cells are detected by activating the memory B cell pool to produce plsma cells/plasma blasts. These are increase in active disease and people who are negative can become positive as  people relapse. This suggests that there are brain reactive  B cells occuring in active MS

Identification of a B cell-dependent subpopulation of multiple sclerosis by measurements of brain-reactive B cells in the blood.
Kuerten S, Pommerschein G, Barth SK, Hohmann C, Milles B, Sammer FW, Duffy CE, Wunsch M, Rovituso DM, Schroeter M, Addicks K, Kaiser CC, Lehmann PV.Clin Immunol. 2014 May-Jun;152(1-2):20-4.

B cells are increasingly coming into play in the pathogenesis of multiple sclerosis (MS). Here, we screened peripheral blood mononuclear cells (PBMC) from patients with clinically isolated syndrome (CIS), MS, other non-inflammatory neurological, inflammatory neurological or autoimmune diseases, and healthy donors for their B cell reactivity to CNS antigen using the enzyme-linked immunospot technique (ELISPOT) after 96 h of polyclonal stimulation. Our data show that nine of 15 patients with CIS (60.0%) and 53 of 67 patients with definite MS (79.1%) displayed CNS-reactive B cells, compared to none of the control donors. The presence of CNS-reactive B cells in the blood of the majority of patients with MS or at risk to develop MS along with their absence in control subjects suggests that they might be indicative of a B cell-dependent subpopulation of the disease.

Categorization of multiple sclerosis relapse subtypes by B cell profiling in the blood.Hohmann C, Milles B, Schinke M, Schroeter M, Ulzheimer J, Kraft P, Kleinschnitz C, Lehmann PV, Kuerten S.
Acta Neuropathol Commun. 2014 Sep 16;2:138.
INTRODUCTION:B cells are attracting increasing attention in the pathogenesis of multiple sclerosis (MS). B cell-targeted therapies with monoclonal antibodies or plasmapheresis have been shown to be successful in a subset of patients. Here, patients with either relapsing-remitting (n = 24) or secondary progressive (n = 6) MS presenting with an acute clinical relapse were screened for their B cell reactivity to brain antigens and were re-tested three to nine months later. Enzyme-linked immunospot technique (ELISPOT) was used to identify brain-reactive B cells in peripheral blood mononuclear cells (PBMC) directly ex vivo and after 96 h of polyclonal stimulation. Clinical severity of symptoms was determined using the Expanded Disability Status Scale (EDSS).
RESULTS:Nine patients displayed B cells in the blood producing brain-specific antibodies directly ex vivo. Six patients were classified as B cell positive donors only after polyclonal B cell stimulation. In 15 patients a B cell response to brain antigens was absent. Based on the autoreactive B cell response we categorized MS relapses into three different patterns. Patients who displayed brain-reactive B cell responses both directly ex vivo and after polyclonal stimulation (pattern I) were significantly younger than patients in whom only memory B cell responses were detectable or entirely absent (patterns II and III; p = 0.003). In one patient a conversion to a positive B cell response as measured directly ex vivo and subsequently also after polyclonal stimulation was associated with the development of a clinical relapse. The evaluation of the predictive value of a brain antigen-specific B cell response showed that seven of eight patients (87.5%) with a pattern I response encountered a clinical relapse during the observation period of 10 months, compared to two of five patients (40%) with a pattern II and three of 14 patients (21.4%) with a pattern III response (p = 0.0005; hazard ratio 6.08 (95% confidence interval 1.87-19.77).
CONCLUSIONS:Our data indicate actively ongoing B cell-mediated immunity against brain antigens in a subset of MS patients that may be causative of clinical relapses and provide new diagnostic and therapeutic options for a subset of patients.