Purpose Deficiency of marginal-zone B cells was observed in peripheral blood (PB) of SLE pts in clinical remission or low disease activity (LDA)¹. Goal of the prospective, comparative, long-term study is follow-up of this phenomenon.

Methods Forty five adult SLE (ACR/1982, updated 1997) pts in complete remission or LDA² and 10 age- and sex-matched healthy controls (HC) were enrolled in „month 0’, and SLE also after twelve-months („month 12’) and 36-months („month 36’) period; overlap syndromes, infection, renal failure and monoclonal gammopathy in SLE were excluded. The DuraClone IM panel (Beckman Coulter) was used to identify CD19⁺CD27⁺IgM⁺ B cell subpopulation in PB samples by flow cytometry navios (Beckman Coulter) with software analysis using Kaluza version 1.2.; data obtained were expressed in relative% of PB lymphocytes and absolute values x10⁶/L, and processed using Medcalc-Statistical Software programme.

Results Significant differences (p =0.002 - <0.001) were obtained between absolute values of CD19⁺CD27⁺IgM⁺ B cells in HC (median 31.36, 95% CI 21.49 – 63.35) and SLE „month 0’ (median 13.17, 95% CI 7.87 – 17.09), SLE „month 12’ (median 10.56, 95% CI 7.24 – 16.04), and SLE „month 36’ (median 9.66, 95% CI 7.22 – 13.21), but not between values obtained in SLE „month 0’, „month 12’ and „month 36’ (p>0.05); not significant differences were found using analysis according to relative% of B cells under study (p>0.05).

Conclusion Data obtained demonstrated a long-term deficiency of marginal-zone B cells in PB of SLE pts in complete remission or LDA; susceptibility to infection should be supposed, but further studies are necessary.

Acknowledgement Research project PROGRES Q40-15, Charles Univ. Faculty of Medicine, Hradec Králové, Czech Republic.

References

1. Hrncir Z, et al. Clin Exper Rheumatol2016;34(S99);S–63.

2. Fanouriakis A, et al. Ann Rheum Dis 2019;78;736–745.