Archiv - November 2009
Interleukin-21 restores immunoglobulin production ex vivo in patients with common variable immunodeficiency and selective IgA deficiency.
Stephan Borte1, Qiang Pan-Hammarström2, Chonghai Liu2, Ulrich Sack1, Michael Borte3, Ulf Wagner4, Dagmar Graf5, and Lennart Hammarström2
1 Department of Clinical Immunology and Transfusion Medicine,
University of Leipzig, Leipzig, Germany
2 Division of Clinical Immunology and Transfusion Medicine, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, Sweden
3 Department of Pediatrics, Municipal Hospital St. Georg Leipzig, Leipzig, Germany
4 Department of Internal Medicine II, University of Leipzig, Leipzig, Germany
5 Physician's practice for Transfusion Medicine and Immunodeficiency, Laboratory Dr. Reising-Ackermann, Leipzig, Germany
Blood, 2009, Vol. 114, No. 19, pp. 4089-4098.
Interleukin-21 (IL-21) is an important promoter for differentiation of human B cells into Ig-secreting cells. The objective of this study was to evaluate an IL-21 based approach to induce immunoglobulin production in B cells from patients with common variable immunodeficiency (CVID) or selective IgA deficiency (IgAD). We show that a combination of IL-21, IL-4 and anti-CD40 stimulation induces class switch recombination to IgG and IgA and differentiation of Ig-secreting cells, consisting of both sIgG+ and sIgA+ B cells and CD138+ plasma cells, in patients with CVID or IgAD. Stimulation with IL-21 was far more effective than stimulation with IL-4 or IL-10. Moreover, spontaneous apoptosis of CD19+ B cells from patients with CVID or IgAD was prevented by a combination of IL-21, IL-4 and anti-CD40 stimulation. Analysis of IL-21 and IL-21R mRNA expression upon anti-CD3 stimulation of T cells, however, showed no evidence for defective IL-21 expression in CVID patients and sequencing of the coding regions of the IL-21 gene did not reveal any mutations, suggesting a regulatory defect. Thus, our work provides an initial basis for a potential therapeutic role of IL-21 to reconstitute immunoglobulin production in CVID and IgAD.