Possible different mechanisms of B cell activation in systemic lupus erythematosus and rheumatoid arthritis: opposite expression of low-affinity receptors for IgE (CD23) on their peripheral B cells.
To clarify the differential state of B cell activation in patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA), we investigated the expression of low-affinity receptor for IgE (Fc epsilon RII; CD23) on their peripheral B cells by a cytofluorometry using H107 (CD23) and Leu-16 (CD20) monoclonal antibodies. The percentage of CD23-negative B cells in total lymphocytes was significantly greater in both groups of patients than in normal subjects, suggesting the hyperactivity of late-phase B cells in both diseases. However, the increase of CD23-negative B cells in RA was brought about by the increased number of total B cells, although that in SLE was mainly based on the relative decrease of CD23-positive B cells. The number of IgD-positive B cells was decreased, and the number of colony-forming B cells was markedly increased in SLE patients. These observations indicate that a B cell abnormality is mainly qualitative in SLE but quantitative in RA.
Kumagai
S
S
Second Division of Internal Medicine, Kyoto University Medical School, Japan.
Ishida
H
H
Iwai
K
K
Tsubata
T
T
Umehara
H
H
Ozaki
S
S
Suginoshita
T
T
Araya
S
S
Imura
H
H
D000328:Adult; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis*; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D006801:Humans; D007073:Immunoglobulin E; D008180:Lupus Erythematosus, Systemic / Q000276:immunology*; D008213:Lymphocyte Activation / Q000276:immunology*; D008875:Middle Aged; D011961:Receptors, Fc / Q000032:analysis*; D017455:Receptors, IgE
D000944:Antigens, Differentiation, B-Lymphocyte; D011961:Receptors, Fc; D017455:Receptors, IgE; D007073:Immunoglobulin E