摘要
The effector functions elicited by the fragment crystallizable (Fc) region of immunoglobulin G (IgG) antibodies are subject to variation by the presence of terminal sialic acid (Sia) residues at asparagine-297 (Asn-297). We have previously shown that the sialic acid-containing (Sia<sup>+</sup>) fraction of intravenous immune globulin (IVIG) influences cell surface marker expression and cytokine/ chemokine secretion during the differentiation and maturation of human dendritic cells (DC). The present study examined the effects of Sia<sup>+</sup> IgG on human peripheral blood mononuclear cell (PBMC)-derived monocyte and macrophage surface marker expression and cytokine/chemokine secretion. Sia<sup>+</sup> IgG induced increased expression of CD80 and dendritic cell immunoreceptor (DCIR) on monocytes, whereas the expression of HLA-DR was decreased. In addition, the production of IL-6, TNFα, IL-1β, and CXCL1 by monocytes was profoundly increased by treatment with Sia<sup>+</sup> IgG. Sia<sup>+</sup> IgG also increased the expression of cell surface markers associated with macrophage polarization (e.g. CD40 and CD206) on monocytes. In macrophage-colony stimulating factor (MCSF) generated macrophages, Sia<sup>+</sup> IgG induced increased production of numerous cytokines/ chemokines including IL-6, TNFα, CXCL1, and IL-10, and the expression of the macrophage surface marker CD163. Our data extended prior observations of Sia<sup>+</sup> IgG on DC function and showed that Sia<sup>+</sup> IgG was able to differentially modulate multiple pathways in monocytes and macrophages. Our data indicate that the Sia<sup>+</sup> fraction of IVIG possesses the ability to influence inflammatory processes in multiple immune cell types and induces novel signatures in cell surface marker expression and cytokine/chemokine production.
The effector functions elicited by the fragment crystallizable (Fc) region of immunoglobulin G (IgG) antibodies are subject to variation by the presence of terminal sialic acid (Sia) residues at asparagine-297 (Asn-297). We have previously shown that the sialic acid-containing (Sia<sup>+</sup>) fraction of intravenous immune globulin (IVIG) influences cell surface marker expression and cytokine/ chemokine secretion during the differentiation and maturation of human dendritic cells (DC). The present study examined the effects of Sia<sup>+</sup> IgG on human peripheral blood mononuclear cell (PBMC)-derived monocyte and macrophage surface marker expression and cytokine/chemokine secretion. Sia<sup>+</sup> IgG induced increased expression of CD80 and dendritic cell immunoreceptor (DCIR) on monocytes, whereas the expression of HLA-DR was decreased. In addition, the production of IL-6, TNFα, IL-1β, and CXCL1 by monocytes was profoundly increased by treatment with Sia<sup>+</sup> IgG. Sia<sup>+</sup> IgG also increased the expression of cell surface markers associated with macrophage polarization (e.g. CD40 and CD206) on monocytes. In macrophage-colony stimulating factor (MCSF) generated macrophages, Sia<sup>+</sup> IgG induced increased production of numerous cytokines/ chemokines including IL-6, TNFα, CXCL1, and IL-10, and the expression of the macrophage surface marker CD163. Our data extended prior observations of Sia<sup>+</sup> IgG on DC function and showed that Sia<sup>+</sup> IgG was able to differentially modulate multiple pathways in monocytes and macrophages. Our data indicate that the Sia<sup>+</sup> fraction of IVIG possesses the ability to influence inflammatory processes in multiple immune cell types and induces novel signatures in cell surface marker expression and cytokine/chemokine production.
