Living life without B cells: is repeated B-cell depletion a safe and effective long-term treatment plan for rheumatoid arthritis?

Abstract Background. Chronic graft-versus-host disease (cGvHD) is a common complication of allogeneic hemopoietic cell transplantation (allo-HCT). The pathogenesis of cGvHD is poorly understood. In cGvHD, the homeostasis of B lymphocytes is perturbed, as demonstrated by the production of autoantibodies. B-cell depletion with monoclonal antibodies (mAb) interferes with autoantibody production and ameliorates signs and symptoms of cGvHD. In mouse models, cGvHD and autoantibodies associate with the long-term persistence of host B cells after allo-HCT (Sylvain Perruche et al., Transplantation 2006). It has been postulated that host B cells may present alloantigens to donor T cells and, in turn, receive help for autoantibody production. This could be crucial to the pathogenesis of cGvHD. Aim. To investigate whether the long-term persistence of host B lymphocytes is associated with cGvHD and autoantibodies in humans. Patients and methods. We recruited 13 consecutive patients with active cGvHD (4 mild, 5 moderate, 4 severe according to NIH classification) with a median time of onset of 6 months (range 3–36) from HLA-identical sibling (9 patients) and HLA-matched unrelated (4) allo-HCT. As controls, we chose 10 patients that underwent HLAidentical sibling (2), HLA-matched unrelated (5) or haploidentical (3) allo-HCT and never experienced cGvHD. In the two groups, we studied: circulating autoantibodies, including anti-nuclear (ANA), anti-DNA, anti-extractable nuclear antigen, anti-beta2 glycoprotein, anti-neutrophil cytoplasm, anti-thyroid, anti-mytocondria antibodies, rheumatoid factor, absolute numbers of T (CD3+, CD4+, CD8+), conventional B (CD19+), B1 (CD5+/CD19+) and NK cells (CD16+/CD56+) in the graft and in the peripheral blood, microchimerism by short-tandem repeats (STR) on B, T and myeloid cells purified by immunomagnetic cell sorting (sensitivity 0,01%). Results. Patients with cGvHD had high-titer circulating ANA (>1:160) more frequently than controls (54% versus 10%, P<0,05). All other autoantibodies were negative. Peripheral T-cell counts were lower in patients with cGvHD than in controls (for CD8+ cells P<0,05). This was not due to a difference in the absolute numbers of T lymphocytes within the graft between the two groups. Peripheral counts of conventional B and B1 cells in patients with cGvHD were similar to controls. Autoantibodies and cGvHD were not associated with the persistence of host B lymphocytes, since the analysis of STR on purified B cells revealed that they were all of donor origin. T and myeloid cells were also of donor origin. Of interest, in univariate analysis, in vivo B-cell depletion with mAb for the prophylaxis against Epstein-Barr virus-related lymphoproliferative disease showed a trend towards a lower risk of cGvHD (P=0,06). Conclusions. This study indicates that autoantibody production during cGvHD does not associate with long-term persistence of host B cells in humans. Moreover, it suggests that the early depletion of donor B lymphocytes in vivo may be effective for GvHD prophylaxis

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Steady-state generation of mucosal IgA+ plasmablasts is not abrogated by B-cell depletion therapy with rituximab

Blood ◽

10.1182/blood-2010-01-266536 ◽

2010 ◽

Vol 116 (24) ◽

pp. 5181-5190 ◽

Cited By ~ 57

Author(s):

Henrik E. Mei ◽

Daniela Frölich ◽

Claudia Giesecke ◽

Christoph Loddenkemper ◽

Karin Reiter ◽

...

Keyword(s):

Rheumatoid Arthritis ◽

Steady State ◽

B Cells ◽

B Cell ◽

Peripheral Blood ◽

Plasma Cells ◽

Cell Depletion ◽

B Cell Depletion ◽

Ki 67

AbstractThe anti-CD20 antibody rituximab depletes human B cells from peripheral blood, but it remains controversial to what extent tissue-resident B cells are affected. In representative patients with rheumatoid arthritis, we here demonstrate that recently activated presumably short-lived plasmablasts expressing HLA-DRhigh and Ki-67 continuously circulate in peripheral blood after B-cell depletion by rituximab at 26%-119% of their initial numbers. They circulate independent of splenectomy, express immunoglobulin A (IgA), β7 integrin, and C-C motif receptor 10 (CCR10) and migrate along CCL28 gradients in vitro, suggesting their mucosal origin. These plasmablasts express somatically hypermutated VH gene rearrangements and spontaneously secrete IgA, exhibiting binding to microbial antigens. Notably, IgA+ plasmablasts and plasma cells were identified in the lamina propria of patients treated with rituximab during peripheral B-cell depletion. Although a relation of these “steady state”–like plasmablasts with rheumatoid arthritis activity could not be found, their persistence during B-cell depletion indicates that their precursors, that is, B cells resident in the mucosa are not deleted by this treatment. These data suggest that a population of mucosal B cells is self-sufficient in adult humans and not replenished by CD20+ B cells immigrating from blood, lymphoid tissue, or bone marrow, that is, B cells depleted by rituximab.

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B-cell-activating factor receptor expression on naive and memory B cells: relationship with relapse in patients with rheumatoid arthritis following B-cell depletion therapy

Annals of the Rheumatic Diseases ◽

10.1136/ard.2010.131326 ◽

2010 ◽

Vol 69 (12) ◽

pp. 2181-2188 ◽

Cited By ~ 30

Author(s):

Inmaculada de la Torre ◽

Rita A Moura ◽

Maria J Leandro ◽

Jonathan Edwards ◽

Geraldine Cambridge

Keyword(s):

Rheumatoid Arthritis ◽

B Cells ◽

B Cell ◽

Memory B Cells ◽

Receptor Expression ◽

Cell Depletion ◽

B Cell Depletion ◽

B Cell Activating Factor ◽

Significant Difference ◽

Cell Repopulation

ObjectivesTo examine the expression of B-cell-activating factor receptor (BAFF-R) on naive CD27− and memory CD27+ B cells in normal individuals and patients with rheumatoid arthritis (RA) undergoing B-cell depletion therapy with rituximab.Patients and MethodsBAFF-R expression on B-cell subsets was determined in normal controls (NC; n=11), active patients with RA pre-rituximab (pre-RX; n=15), relapsing patients either concordant for B-cell repopulation (C-R, n=13) or discordant, with relapse more than 3 months after repopulation (D-R, n=11) and patients in remission over 3 months postrepopulation (discordant non-relapsing (D-NR), n=5). Serum BAFF was measured by ELISA and analysed using Mann–Whitney.ResultsThere was no significant difference between NC, pre-RX and D-NR patients in %BAFF-R-positive B cells or mean fluorescence intensity (MFI) in naive and memory B cells. Relapsing patients had significantly lower MFI and %BAFF-R-positive cells in both naive and memory compartments from NC and pre-RX (C-R and D-R; p<0.01). BAFF levels in pre-RX patients were within the normal range and did not correlate with BAFF-R expression in any patient group. D-NR patients had relatively lower proportions of pre and postswitch CD27+ B cells than pre-RX patients (D-NR vs pre-RX; p<0.05 for both) and also lower numbers of postswitch B cells than D-R patients (D-NR vs D-R, p<0.05).ConclusionBAFF-R expression was significantly reduced on both naive and memory B cells in patients at relapse, regardless of the relationship with B-cell repopulation or serum BAFF levels. Re-establishment of active disease was also associated with an increase in class-switch recombination. Factors responsible for lower levels of BAFF-R may relate to altered thresholds for autoreactive B-cell generation at relapse in patients with RA.

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