Modulation of lymphocyte phenotype and function by immunoglobulins

Background Immunoglobulins have immune-modulating capacities and are used for the treatment of different dermatological diseases. They have also been reported for the treatment of severe atopic dermatitis (AD). Objectives To determine the effects of immunoglobulins on the phenotype and function of peripheral T and B lymphocytes from patients with AD in comparison with healthy donors (HD) as controls. Methods We studied lymphocyte activation and T-cell cytokine production from 12 patients with AD and 10 HD by multicolour flow cytometric analysis in the presence of immunoglobulins. Results Immunoglobulins significantly inhibited T-cell activation (CD69), by 71% (AD) and by 62% (HD). Production of interferon-gamma and interleukin-4 was also significantly inhibited, by 44%/24% (AD) and 38%/10% (HD), respectively. In addition, CD86 expression on B lymphocytes was downregulated by 30% in AD and by 29% in HD, whereas CD23 expression was decreased without reaching statistical significance. Conclusions Our data demonstrate that, in vitro, immunoglobulins modulate the activation and cytokine production of peripheral blood lymphocytes from both HD and patients with AD.