Objectives: The aim of the study was to analyze the frequency and distribution of B cells subsets in a cohort of patients with SLE with different organ involvement and the possible correlation with disease activity. Methods: 60 SLE patients (53 females; mean age 39.0±13.6 years; 29 with renal, 21 with articular, 4 with CNS, 4 with vascular and 2 with cutaneous involvement; 30 with an active disease-SLEDAI>10) and 30 healthy controls matched for age and sex were analyzed for the distribution of circulating PB B cell subpopulations by staining for CD19, CD38, and IgD in combination with the B cell memory marker CD27, by flow cytometry. Results: Considering the Bm1-Bm5 classification, there was no difference in the percentage of B cells subpopulations between SLE patients and controls. Instead, SLE patients showed an higher percentage of CD19+/ZAP70+ cells (6.1±6.2%) compared with controls (2.1±1.4, p=0.01). In SLE patients, disease activity index (SLEDAI) correlated positively with the percentage of CD19+ cells (r=0.43, p=0.001) and with the absolute number of CD19+/CD27+/IgD- (r= 0.42, p=0.004), CD19+/CD27+/CD38+ (r=0.37, p=0.01), CD19+/CD27-/IgD- (r=0.31, p=0.04) and CD19+/ZAP70+ (r=0.41, p=0.005). SLE patients with an active disease had an higher percentage of CD19+ cells compared with patients with inactive disease (11.0±7.9% vs 4.4±4.2% respectively, p<0.001). Patients with active disease had an higher absolute number of memory cells (eBm5+Bm5 34±36/ul, CD19+/CD27+/IgD- 16±17), CD19+/CD27+CD38+ (10±13) and CD19+/ZAP70+ (7±10) compared with patients with inactive disease (eBm5+Bm5: 12±12, p=0.001; CD19+/CD27+/IgD-: 5±5, p<0.001; CD19+/CD27+CD38+: 3±3, p=0.001; CD19+/ZAP70+: 2±3, p=0.04). The distribution of Bm1-Bm5 and IgD/CD27 subsets was similar in patients with renal and articular involvement, even though considering only the subgroup with active disease, patients with renal involvement showed an higher percentage of memory B cells (eBm5+Bm5 36.3±21.2%) and of CD19+/CD27+CD38+ (11.8±8.6%) compared with patients with articular involvement (eBm5+Bm5: 15.0±8.5%, p=0.003; CD19+/CD27+CD38+: 5.0±4.0%, p=0.03). This difference was also confirmed by the ratio Bm2+Bm2'/eBm5+Bm5 in active renal disease (2.1±2.9) compared to 6.5±6.0 in active articular disease (p=0.005). Moreover, SLE patients with active renal disease had an higher percentage of CD19+/ZAP70+ cells (7.1±5.0) compared with patients with active articular involvement (3.3±2.6, p=0.04). Conclusion: SLE patients showed a significant reduction of memory B cells compared with controls, regardless of the organ involvement. An increase of memory B cells appeared, however, in patients with renal active engagement, while an higher percentage of active cells was present in patients with active articular involvement.
Peripheral blood B cells subsets in patients with systemic lupus erythematosus: correlation with disease activity and organ involvement
Gremese E;
2010-01-01
Abstract
Objectives: The aim of the study was to analyze the frequency and distribution of B cells subsets in a cohort of patients with SLE with different organ involvement and the possible correlation with disease activity. Methods: 60 SLE patients (53 females; mean age 39.0±13.6 years; 29 with renal, 21 with articular, 4 with CNS, 4 with vascular and 2 with cutaneous involvement; 30 with an active disease-SLEDAI>10) and 30 healthy controls matched for age and sex were analyzed for the distribution of circulating PB B cell subpopulations by staining for CD19, CD38, and IgD in combination with the B cell memory marker CD27, by flow cytometry. Results: Considering the Bm1-Bm5 classification, there was no difference in the percentage of B cells subpopulations between SLE patients and controls. Instead, SLE patients showed an higher percentage of CD19+/ZAP70+ cells (6.1±6.2%) compared with controls (2.1±1.4, p=0.01). In SLE patients, disease activity index (SLEDAI) correlated positively with the percentage of CD19+ cells (r=0.43, p=0.001) and with the absolute number of CD19+/CD27+/IgD- (r= 0.42, p=0.004), CD19+/CD27+/CD38+ (r=0.37, p=0.01), CD19+/CD27-/IgD- (r=0.31, p=0.04) and CD19+/ZAP70+ (r=0.41, p=0.005). SLE patients with an active disease had an higher percentage of CD19+ cells compared with patients with inactive disease (11.0±7.9% vs 4.4±4.2% respectively, p<0.001). Patients with active disease had an higher absolute number of memory cells (eBm5+Bm5 34±36/ul, CD19+/CD27+/IgD- 16±17), CD19+/CD27+CD38+ (10±13) and CD19+/ZAP70+ (7±10) compared with patients with inactive disease (eBm5+Bm5: 12±12, p=0.001; CD19+/CD27+/IgD-: 5±5, p<0.001; CD19+/CD27+CD38+: 3±3, p=0.001; CD19+/ZAP70+: 2±3, p=0.04). The distribution of Bm1-Bm5 and IgD/CD27 subsets was similar in patients with renal and articular involvement, even though considering only the subgroup with active disease, patients with renal involvement showed an higher percentage of memory B cells (eBm5+Bm5 36.3±21.2%) and of CD19+/CD27+CD38+ (11.8±8.6%) compared with patients with articular involvement (eBm5+Bm5: 15.0±8.5%, p=0.003; CD19+/CD27+CD38+: 5.0±4.0%, p=0.03). This difference was also confirmed by the ratio Bm2+Bm2'/eBm5+Bm5 in active renal disease (2.1±2.9) compared to 6.5±6.0 in active articular disease (p=0.005). Moreover, SLE patients with active renal disease had an higher percentage of CD19+/ZAP70+ cells (7.1±5.0) compared with patients with active articular involvement (3.3±2.6, p=0.04). Conclusion: SLE patients showed a significant reduction of memory B cells compared with controls, regardless of the organ involvement. An increase of memory B cells appeared, however, in patients with renal active engagement, while an higher percentage of active cells was present in patients with active articular involvement.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
