Presentation of peripheral CD27++ plasma cells in systemic lupus erythematosus patients
I was interested in the study about CD27++ plasma cells by Ten Boekel et al., in which they evaluate longitudinal data of CD27++ plasma cells in systemic lupus erythematosus (SLE) patients.  There are many factors influencing the expression of peripheral CD27++ plasma cells in SLE patients, including infection and immunosuppressive drugs. [2,3] In our pervious study, although the expression of peripheral CD27++ plasma cells was found to have correlation with SLE disease activity (SLE disease activity index, levels of anti-dsDNA, C3 and C4), bacterial or viral infection seemed affect the expression of peripheral CD27++ plasma cells profoundly.  Further more, our unpublished data showed that SLE patients who received immunosuppressive therapy with leucopenia or suppressed bone marrow had persistent low percentage of peripheral CD27++ plasma cells, which could be explanation of non-consistent correlation between peripheral CD27++ plasma cells and SLE disease activity in the present study of Ten Boekel et al. Two major factors including bacterial or viral infection and administration of immunosuppressive drugs (such as azathiopurine, cyclophosphamide and rituximab) might affect the presentation of peripheral CD27++ plasma cells. When SLE patients have infection, peripheral CD27++ plasma cells should not be used to evaluate disease activity.
1. Ten Boekel E, Prins M, Vrielink GJ, et al. Longitudinal studies of the association between peripheral CD27++ plasma cells and systemic lupus erythematosus disease activity: preliminary results. Ann Rheum Dis 2010 Nov 12.
2. Dorner T, Lipsky PE. Correlation of circulating CD27high plasma cells and disease activity in systemic lupus erythematosus. Lupus 2004;13:283-9.
3. Ten Boekel E, Siegert CE, Vrielink GJ, et al. Analyses of CD27++ plasma cells in peripheral blood from patients with bacterial infections and patients with serum antinuclear antibodies. J Clin Immunol 2007;27:467-76.
4. Yang DH, Chang DM, Lai JH, et al. Significantly higher percentage of circulating CD27(high) plasma cells in systemic lupus erythematosus patients with infection than with disease flare-up. Yonsei Med J 2010;51:924-31.