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c-Jun N-terminal kinase (JNK) is a critical mitogen activated protein kinase (MAPK) implicated in inflammatory processes, with IQ-1S (11H-indeno[1,2-b]quinoxalin-11-one oxime sodium salt) being a high-affinity JNK inhibitor with pronounced anti-inflammatory properties. Here, we studied direct effects of IQ-1S on phenotypical and cytokine-producing characteristics of activated human monocytes/macrophages and T cells in vitro. Purified monocyte/macrophage cells were activated by bacterial lipopolysaccharide (LPS, 1 μg/ml) for 24 h, while T cells were activated by particles conjugated with antibodies (Abs) against human CD2, CD3, and CD28 for 48 h. Treatment with IQ-1S (0.5-25 μМ) in the presence of LPS reduced percentages of CD197 (CCR7)-positive cells in macrophage cultures, without affecting CD16 + (FcγRIII, low-affinity Fc-receptor), CD119 + (interferon-γ receptor 1), and CD124 + (IL-4 receptor α-subunit) cells. In addition, IQ-1S reduced production of tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, and IL-10 in macrophage cultures. In activated T cell cultures, IQ-1S decreased CD25 + cell numbers in both CD4-positive and CD4-negative T cell compartments. Central memory СD45RA - /СD197 + and effector memory СD45RA - /СD197 - T cells were more sensitive to IQ-1S-mediated suppression, as compared to naïve СD45RA + /СD197 + and terminally-differentiated effector СD45RA + /СD197 - T cells. IQ-1S also suppressed T-cell cytokine production (IL-2, interferon-ɣ, IL-4, and IL-10). Collectively, the results suggest that both human macrophage and T cells could be immediate cell targets for IQ-1S-based anti-inflammatory immunotherapy. IQ-1S-mediated suppressive effects were unlikely to be associated with macrophage/T helper polariation., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

We studied direct effects of human granulocyte colony-stimulating factor (G-CSF) on phenotypical properties of human macrophage cells in vitro . CD14 + monocyte/macrophages (Mc/Mphs) were isolated from blood of healthy donors by positive magnetic separation. G-CSF (0.01-1.0 ng/mL), when added to Mc/Mphs along with lipopolysaccharide (LPS, 1.0 μg/mL), was able to noticeably reduce proportions of CD119 (interferon-γ receptor 1)-positive cells, with no stable effects on CD16 (FcγRIII) + and СD124 (IL-4 receptor subunit alpha)-positive cells. In addition, G-CSF markedly upregulated IL-6 production by LPS-activated Mph cells, without significantly affecting IL-1β, IL-10 and tumor necrosis factor-α (TNF-α) secretion. Our data suggests that G-CSF could restrain Mph polarization to pro-inflammatory (M1) phenotype, thus potentially supporting pro-regenerative Mph activity with implications for immunotherapeutic interventions.

Background : We studied direct effects of human granulocyte-macrophage colony stimulating factor (GM-CSF) on phenotypical characteristics and cytokine-production of non-activated and activated human monocytes/macrophages (Mc/Mphs) and T cells. Methods : Purified Mc/Mphs were activated by bacterial lipopolysaccharide (LPS, 1 μg/ml) for 24 h, while T cells were activated by particles conjugated and antibodies (Abs) against human CD2, CD3, and CD28 for 48 h. Results : GM-CSF treatment (0.01-10 ng/ml) was shown to reduce percentages of CD197 (CCR7)-positive cells in non-activated Mph cultures, without affecting significantly CD14 + (LPS co-receptor), CD16 + (FcγRIII, low-affinity Fc-receptor), CD119 + (interferon-gamma receptor 1), and CD124 + (IL4 receptor α-subunit) cells. In addition, GM-CSF reduced relative numbers of CD197 + cells, as well as CD14 + , CD16 + , and CD119 + cells in activated Mph cultures without affecting CD124 + cell distribution. GM-CSF at the highest dose of 10 ng/ml enhanced TNF-α and IL-6 (but not IL-1β and IL-10) production in activated Mc/Mphs. In activated T cell cultures, GM-CSF at 0.1-1.0 ng/ml augmented CD38 + cell numbers in naïve СD45RA + /СD197 + and central memory СD45RA - /СD197 + cell subsets, with no effect on effector СD45RA - /СD197 - and terminally differentiated effector СD45RA + /СD197 - cells. GM-CSF at a low dose (0.01 ng/ml) down-regulated INF-γ production, while at a high dosage (10.0 ng/ml) up-regulated IL-2 and IL-4 production. Conclusion : In general, the results suggest that GM-CSF is able to facilitate the implication of both Mph and T cells in the adaptive immunogenesis.

Interleukin-8 (IL-8, CXCL8) belongs to major chemokines to stimulate migration of neutrophils and monocytes/macrophages (Mc/Mphs) into the inflammation sites. We studied the direct effects of IL-8 on the functionality of human Mc/Mphs in vitro. CD14-positive cells were isolated from human peripheral blood mononuclear cells (PBMCs) by positive magnetic separation and were further cultured with or without lipopolysaccharide (LPS, 1.0 μg/ml) for 24 h. We showed that upon LPS activation of Mc/Mphs, IL-8 reduced markedly both the percentages and median fluorescence intensity (MFI) of CD16 (FcγRIII)-positive cells among CD14 high cells, as well as in cells that reduced the expression of СD14 during their culturing. IL-8 was also found to be capable of reducing the expression of СD124 (IL-4 receptor subunit alpha, IL-4RA), with concomitant enhancement of the expression of both CD119 (interferon-gamma receptor 1) and CD197 (CCR7) in Mph cells. In addition, IL-8 up-regulated production of IL-6 and IL-1β [but not tumor necrosis factor-α (TNF-α) and IL-10] by activated Mc/Mphs. Our results suggest the ability for IL-8 to directly favor pro-inflammatory M1-type Mph activity., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objective: We studied direct effects of Erythropoietin (Epo) on functional properties of human monocytes/macrophages (Mc/Mphs) in vitro., Methods: Cells expressing CD14 marker were isolated from human peripheral blood mononuclear cells (PBMCs) by positive magnetic separation. Mc/Mphs were cultured without or with bacterial lipopolysaccharide (LPS) in the absence or presence of Epo for 24 h., Results: We showed that Epo treatment hoticeably reduces the percentages of CD14+ cells, CD124 (alpha subunit of IL-4 receptor)+ cells and CD197 (CCR7)+ cells in non-activated Mph cultures without affecting the levels of CD16 (low-affinity Fc-receptor)+ and CD119 (interferon-γ (IFN-γ) receptor)+ cells. Epo also markedly reduced percentages of CD197+ cells in LPS-activated Mc/Mphs, without significantly affecting the expression of all other molecular markers studied. In addition, Epo caused moderate up-regulation of interleukin-1β (IL-1β) and IL-6 production in resting Mc/Mph cultures, as compared to the down-regulation of IL-1β and IL-6 production in LPS-activated cells. No Epomediated effects on tumor necrosis factor-α (TNF-α) and IL-10 production were observed., Conclusion: Our data suggests that Epo effects on Mph functionality are largely dependent on the baseline activation status of these cells, and that Epo exerts no distinct direct effects on the particular Mph polarization pathway., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

On the basis of the data indicating the existence of two types of immuno-protection, namely macrophage-mediated and mast cell-basophil-mediated, it is argued that by reacting with potential pathogens, pre-existing IgM and IgG antibodies (both natural and induced by environmental microflora) might promote involvement of macrophages in the presentation process, favouring the generation of pathogen-specific T helper 1 (Th1), but not Th2, responses. Alternatively, the failure of these antibodies to effectively recognize pathogens might be associated with active involvement of pathogen-specific B cells in presenting Ag and, as a consequence, with the predominant development of Th2, rather than Th1, responses.

Antigen-presenting ability of monocytes/macrophages (Mc/Mph) was studied in 26 patients with pulmonary tuberculosis and in 21 healthy donors. The above investigation has demonstrated that the ability of the Mc/Mph patients to present mycobacterial antigens was not only intact, but also appeared to be even higher than the reference values of Mc/Mph antigen presentation in healthy donors (0.7 and 0.28, respectively). The ability of Mc/Mph to secrete interleukin-1 (IL-1) both spontaneously and as a response to muramil dipeptide, a synthetic macrophage activator, was studied in 24 tuberculosis patients and 15 healthy donors. During the experiment it was revealed that the affected and healthy cells binding to a plastic surface do not differ in their spontaneous production of IL-1 (0.8 and 0.79, respectively). At the same time in response to muramil dipeptide stimulation, the Mc/Mph patients produced lesser IL-1 than those of the healthy donors stimulated under the similar conditions (3.2 +/- 1.1 and 10.6 +/- 3.6, respectively).