Study of the B cell memory compartment in common variable immunodeficiency.
We evaluated the B cell memory pool among blood B cells from 20 patients with common variable immunodeficiency (CVID). CD27+ B cell number was normal or increased in 6 patients (with 95% CD27+ B cells in 1 patient) and decreased in 14 patients. In 13 or 15 patients studied, the CD27 molecule was detectable on less than 50% IgG or IgA B cells, indicating a defect in the maturation of these memory cells. Within the group of patients with a low number of CD27+ B cells, no up-regulation of this molecule was observed after in vitro stimulation of purified B cells from 3 of 5 patients studied, suggesting an intrinsic B cell defect. In addition, ligation of the CD27 molecule was unable to trigger terminal differentiation of purified B cells in 1 of 2 cases with a large number of CD27+ B cells. Finally, the CD27 ligand was normally expressed on activated T cells in only 5 of 14 patients studied. These data confirm the heterogeneity of immunological defects in patients with CVID. Abnormal expression and/or function of the CD27-CD70 members of the TNF/TNF receptor family contribute to the immunological defect.
Brouet
J C
JC
Department of Immuno-Hematology, Hematology Institute of Paris VII University, Hôpital Saint-Louis, France. jc.brouet@chu-stlouis.fr
Chedeville
A
A
Fermand
J P
JP
Royer
B
B
D015703:Antigens, CD; D001402:B-Lymphocytes / Q000276:immunology*; D053282:CD27 Ligand; D017252:CD3 Complex / Q000276:immunology; D002454:Cell Differentiation; D017074:Common Variable Immunodeficiency / Q000276:immunology*; D006801:Humans; D007156:Immunologic Memory; D008213:Lymphocyte Activation; D008565:Membrane Proteins / Q000032:analysis*; D013601:T-Lymphocytes / Q000276:immunology; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7 / Q000032:analysis*
D015703:Antigens, CD; D053282:CD27 Ligand; D017252:CD3 Complex; C505771:CD70 protein, human; D008565:Membrane Proteins; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7