Expansion of autoreactive unresponsive CD21-/low B cells in Sjögren's syndrome-associated lymphoproliferation

Arthritis Rheum. 2013 Apr;65(4):1085-96. doi: 10.1002/art.37828.


Objective: Primary Sjögren's syndrome (SS) is an autoimmune disease associated with a high risk of developing non-Hodgkin's lymphoma. This study was undertaken to determine the nature of B cells driving lymphoproliferation in primary SS.

Methods: B cell subsets and function were analyzed in peripheral blood from 66 adult patients with primary SS (including 14 patients with B cell lymphoproliferative disease [LPD]) and 30 healthy donors, using flow cytometry, calcium mobilization, and gene array analysis. The reactivity of recombinant antibodies isolated from single B cells from patients with primary SS and LPD was tested using an enzyme-linked immunosorbent assay.

Results: We observed an expansion of an unusual CD21-/low B cell population that correlated with lymphoproliferation in patients with primary SS. A majority of CD21-/low B cells from patients with primary SS expressed autoreactive antibodies, which recognized nuclear and cytoplasmic structures. These B cells belonged to the memory compartment, since their Ig genes were mutated. They were unable to induce calcium flux, become activated, or proliferate in response to B cell receptor and/or CD40 triggering, suggesting that these autoreactive B cells may be anergic. However, CD21-/low B cells from patients with primary SS remained responsive to Toll-like receptor (TLR) stimulation. Molecules specifically expressed in CD21-/low B cells that are likely to induce their unresponsive stage were detected in gene array analyses.

Conclusion: Patients with primary SS who display high frequencies of autoreactive and unresponsive CD21-/low B cells are susceptible to developing lymphoproliferation. These cells remain in peripheral blood controlled by functional anergy instead of being eliminated, and chronic antigenic stimulation through TLR stimulation may create a favorable environment for breaking tolerance and activating these cells.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • B-Lymphocyte Subsets / cytology*
  • B-Lymphocyte Subsets / immunology
  • Calcium / metabolism
  • Case-Control Studies
  • Clonal Anergy
  • Cryoglobulinemia / complications
  • Cryoglobulinemia / genetics
  • Cryoglobulinemia / immunology
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Flow Cytometry
  • Gene Expression Profiling
  • Humans
  • Lymphoma, B-Cell / complications
  • Lymphoma, B-Cell / genetics
  • Lymphoma, B-Cell / immunology
  • Lymphoproliferative Disorders / genetics
  • Lymphoproliferative Disorders / immunology*
  • Male
  • Middle Aged
  • Oligonucleotide Array Sequence Analysis
  • RNA, Messenger / analysis
  • Receptors, Complement 3d / genetics
  • Receptors, Complement 3d / metabolism*
  • Sjogren's Syndrome / genetics
  • Sjogren's Syndrome / immunology*


  • RNA, Messenger
  • Receptors, Complement 3d
  • Calcium