Interleukin 10 is a potent growth and differentiation factor for activated human B lymphocytes.

TLDR

Interleukin‑10, a TH2 cytokine that suppresses TH1 cytokine production, is homologous to Epstein‑Barr virus–encoded IL‑10. Human and viral IL‑10 stimulate DNA replication and survival of antigen‑ or CD40‑activated B cells, synergize with IL‑4 to enhance secretion of IgG, IgA, and IgM, and together promote secretion of all four immunoglobulin isotypes, indicating IL‑10 amplifies humoral responses.

Abstract

Interleukin 10 (IL-10), originally identified as a TH2 helper T-cell product able to inhibit cytokine production by TH1 cells, is highly homologous to BCRF1 (viral IL-10), an open reading frame in the Epstein-Barr virus genome. Here, we show that human and viral IL-10 stimulate DNA replication of B lymphocytes activated either via their antigen receptor or via their CD40 antigen. IL-4 and IL-10 display additive effects and induce a strong increase in the number of viable cells. Moreover, IL-10 induces activated B cells to secrete large amounts of IgG, IgA, and IgM, and the combination of IL-10 and IL-4 results in the secretion of the four immunoglobulin isotypes. Thus, IL-10 may play an important role in the amplification of humoral responses.