Effect of macrophage-activating factor (GcMAF-RF) upon ex vivo polarization of macrophages, activation of dendritic cells and production of cytokines by human whole blood cells

Abstract

This article is the second communication in a series of articles devoted to the effects of a domestic preparation of macrophage-activating factor (GcMAF-RF) and assessment of its biological properties. The aim of this work was to study the effect of the GcMAF-RF upon M0 → M1 polarization of macrophages (Mph), and activation of the professional properties of ex vivo generated antigen-presenting dendritic cells (DC), as well as on ex vivo production of pro-inflammatory (TNFα, IL-1β, IL-6, IFNγ, IL-17, IL-18) and anti-inflammatory (TGF-β, IL-4, IL-10) cytokines, growth factors (IL-2, GM-CSF, G-CSF, VEGF) and chemokines (MCP, IL-8) by the whole blood cells from healthy donors. Mph and DC were generated from the monocytes (3 to 5×106 /ml) derived from adherent fraction of peripheral blood mononuclear cells (MNC) of healthy donors. Granulocyte/macrophage colony-stimulating factor (rhGM-CSF) was used to obtain Mph, whereas DC production was induced by GM-CSF and interferon-α. To provide M1 polarizing signals, bacterial lipopolysaccharide (LPS from E. coli 0114:B4) was used in controls. In experimental series, GcMAF-RF was added 48 h before the end of culture. The stimulating effect of the obtained Mph and DC upon cell proliferation was assessed in allogeneic mixed culture of leukocytes (alloMLC) using radiometric technique, by 3 H-thymidine incorporation. The influence index (IR) of Mph or DC upon allo-SCL was calculated as the ratio of the proliferative response of MNCs in the presence of Mph, or DC to the level of spontaneous MNC proliferation. To determine the cytokine production by human whole blood cells ex vivo, peripheral blood samples from 3 donors with two replicate GcMAF-RF preparations were used, at a total of 6 points. All variants of the study were carried out with mitogen-activated and non-activated blood cells. The cytokine content was determined by the ELISA assays. The effects of GcMAF-RF were quantified as a fold increase (FI), i.e., the ratio of cytokine production in the presence of GcMAF-RF to the level of their spontaneous production. It was shown that the GcMAF-RF preparation was as effective, as lipopolysaccharide (LPS), the standard Mph and DC activator which induces polarization of differentiated M0-macrophages into M1 cells and final maturation of DCs, manifesting by a significant increase in their allo-stimulatory activity in a mixed leukocyte culture (allo-MLC). Moreover, GcMAF-RF stimulates production of numerous cytokines and chemokines (TNFα, IL-1β, IL-6, IL-18, IL-4, IL-10, GM-CSF, G-CSF, VEGF, IL-8), by blood cells (granulocytes, lymphocytes, monocytes), thus indicating direct participation of the macrophage activator GcMAF-RF in various immune processes. The domestic GcMAF-RF drug induces polarization of macrophages M0 → M1, final maturation of DCs and allostimulating activity of Mf and DCs, and is also able to effectively stimulate circulating blood cells to synthesize cytokines/chemokines with pro-inflammatory and immunoregulatory activities.