Diverse activation and differentiation of multiple B cell subsets in patients with atopic dermatitis but not in patients with psoriasis.
BACKGROUND Atopic dermatitis (AD) and psoriasis pathogeneses involve skin barrier impairment and immune dysregulation; however, the contribution of B cell imbalances to these diseases has not yet been determined. OBJECTIVE We sought to quantify B cell populations and antibody secreting cells in the blood of patients with AD, patients with psoriasis, and control subjects. METHODS We studied 34 adults with moderate to severe AD (mean SCORAD score, 65) 24 patients with psoriasis (mean Psoriasis Area and Severity Index score, 16) and 27 healthy subjects using an 11 color flow cytometric antibody panel. IgD/CD27 and CD24/CD38 core gating systems were used to determine frequencies of plasmablasts and naive, memory, transitional, and activated B cells. RESULTS We measured increased CD19()CD20( B cell counts in the skin and blood of patients with AD (P .01) Significantly higher frequencies of chronically activated CD27( memory and nonswitched memory B cells were observed in patients with AD (P .05) with lower values of double negative populations (4% for patients with AD vs. 7% for patients with psoriasis [P .001] and 6% for control subjects [P .02] CD23 expression was highest in patients with AD and correlated with IgE levels (P .01) and disease severity (r 0.6, P .0002) Plasmablast frequencies and IgE expression were highest in all memory subsets of patients with AD (P .01) Finally, CD19()CD24()CD38( transitional and CD19()CD24( )CD38( new memory B cell counts were higher in patients with AD versus those in patients with psoriasis (2.8% vs. 1.4% [P .001] and 9.2% vs. 5.7% [P .02] respectively) CONCLUSIONS AD is accompanied by systemic expansion of transitional and chronically activated CD27( memory, plasmablast, and IgE expressing memory subsets. These data create a critical basis for the future understanding of this debilitating skin disease.
The Journal of allergy and clinical immunology