Mechanism of Allergy & Immunology
P Jeannin, S Lecoanet, Y Delneste, et al (Geneva Biomedical Research Inst; Glaxo Wellcome Research and Development SA, Geneva)
IgE Versus IgG4 Production Can be Differentially Regulated by IL-10
J Immunol 160:3555-3561, 1998.93
The authors have studied the effects of interleukin (IL)-10 on the production of IgE and IgG4.
The methods implemented are in-vitro experiments using peripheral blood mononuclear cell cultures, the addition of IL-10 during the first 3 days of culture was associated with reductions in IL-4-induced Î transcript expression and IgE production. Thus IL-10 apparently decreased IL-4-induced switching. However, when IL-10 was apparently decreased IL-4 induced switching . However, when IL-10 was added to B cells that had already undergone IgE switching, it had a potentiating effect on IgE production. Addition of IL-10 at any time during culture led to increased IL-4-induced g4 transcript expression and IgG4 production.
The study provides us with new insights into the regulation of IgE synthesis. It is known that IL-10 is an anti-inflammatory cytokine due to its effects on cellular immunity. IL-10 however, has important activating activities toward humoral immunity and supports B-cell differentiation, proliferation, and IgG secretion. The current study is important as it increases our knowledge regarding the role of IL-10 in allergic immunity. When given early in an immune response, IL-10 will act primarily through its activity of inhibiting IL-4 production, thus inhibiting the Î isotype switch and IgE secretion. But when given after B cells have already become committed to IgE secretion, IL-10 by activating and differentiating those B cells, actually increase IgE secretion. The effects of IL-10 or IgG4 are primarily those consistent with this role in activating humoral immunity, and what is observed is enhanced IgG4 production at any time during the immune response. High concentration of IL-10 observed during an ongoing allergic response of individuals with atopic dermatitis subsequent to an allergen challenge, may contribute to the extraordinarily high IgE concentrations seen in those individuals.