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Updated: Jun 15, 2026

Natural Killer (NK) and CAR-NK Cell Expansion Method using Membrane Bound-IL-21-Modified B Cell Line
Published on: February 8, 2022
Complement receptor 2/CD21- human naive B cells contain mostly autoreactive unresponsive clones
Isabelle Isnardi1, Yen-Shing Ng, Laurence Menard
1Laboratory of Molecular Immunology, Hospital for Special Surgery, New York, NY, USA.
Abstract:
Complement receptor 2-negative (CR2/CD21(-)) B cells have been found enriched in patients with autoimmune diseases and in common variable immunodeficiency (CVID) patients who are prone to autoimmunity. However, the physiology of CD21(-/lo) B cells remains poorly characterized. We found that some rheumatoid arthritis (RA) patients also display an increased frequency of CD21(-/lo) B cells in their blood. A majority of CD21(-/lo) B cells from RA and CVID patients expressed germline autoreactive antibodies, which recognized nuclear and cytoplasmic structures. In addition, these B cells 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. Moreover, gene array analyses of CD21(-/lo) B cells revealed molecules specifically expressed in these B cells and that are likely to induce their unresponsive stage. Thus, CD21(-/lo) B cells contain mostly autoreactive unresponsive clones, which express a specific set of molecules that may represent new biomarkers to identify anergic B cells in humans.
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