We studied suppressor potential of myeloid-derived suppressor cells (MDSC) in multiple myeloma patients, including before and after mobilization of hematopoietic stem cells (HSC), by evaluating the ...expression of arginase-1 (Arg1), indolamine-2,3-dioxygenase (IDO), and PD-L1 in MDSC subsets. The study included 20 multiple myeloma patients in remission, 5 patients with progression, as well as 10 sex-and age-matched healthy donors. The expression of Arg1, IDO, and PD-L1 in circulating granulocytic MDSC (G-MDSC, Lin
–
HLA-DR
–
CD33
+
CD66b
+
), monocytic MDSC (M-MDSC, CD14
+
HLA-DR
low/–
), and early-stage MDSC (E-MDSC, Lin
–
HLA-DR
–
CD33
+
CD66b
–
) was evaluated by flow cytometry. Multiple myeloma patients in remission were characterized by reduced expression of Arg1 in M-MDSC in comparison with donors. The expression of Arg1 in M-MDSC depended on the number of induction therapy lines performed and was significantly lower in patients who received ⩾2 lines and responded with remission. Patients with multiple myeloma progression (resistant to therapy) showed significantly increased expression of Arg1 and PD-L1 in M-MDSC, as well as increased expression of Arg1 in E-MDSC. After G-CSF-induced mobilization of HSC, the content of circulating Arg1-expressing M-MDSC increased significantly. Considering the presence of MDSC in apheresis products, MDSC suppressive activity is discussed as a factor affecting the outcomes of autologous HSC transplantation in multiple myeloma patients.
We studied the expression of arginase-1 (Arg1) and tyrosine kinase Mer (MerTK) in GMCSF-differentiated human macrophage populations М0, М1(IFNγ), М2а(IL-4), and М2(low serum) generated under ...conditions of growth/serum factor deficiency. The maximum relative content of Arg1+ and MerTK+ cells was found in М2 macrophage populations: М2а(IL-4) and М2(low serum). As the uptake of apoptotic cells is the key mechanism of M2 polarization during M2(low serum) generation, we performed a special series of experiments and showed that incubation with allogeneic apoptotic neutrophils significantly increased the percentages of CD206+ macrophages co-expressing Arg1 and MerTK.
We studied angiogenin production by human macrophages and evaluated the role of this factor in the macrophage-mediated regulation of fibroblasts. All macrophage subtypes, and especially the ...efferocytosis-polarized macrophages, M2(LS), actively produced angiogenin. Exogenous recombinant angiogenin dose-dependently enhanced the proliferation and differentiation of dermal fibroblasts. The addition of the angiogenin inhibitor to fibroblasts cultures suppressed the stimulating effect of exogenous angiogenin or M2(LS) conditioned media. These findings indicate the involvement of angiogenin in the macrophage-mediated paracrine regulation of skin fibroblasts.
Although major progress has been made in the standard treatment for glioblastomas, encompassing the maximal surgical resection, chemotherapy and radiation therapy, it is possible to increase survival ...rates significantly only in a few patients. Therefore, it is necessary to explore new therapeutic modalities, one of which is immunotherapy.
was to evaluate the efficacy of the combined use of autologous and pooled tumor lysates in comprehensive treatment of patients with glioblastoma.
All patients (n=58, including 30 males and 28 females aged 18-70 years) were randomized into three groups, two of which received immunotherapy based on injection of autologous dendritic cells pulsed with autologous tumor lysates (first protocol) or pooled lysates (second protocol) from more than one tumor, in addition to the planned standard treatment. The patients of group 3 (control) received the standard comprehensive treatment encompassing the maximum safe tumor resection followed by radiation therapy and chemotherapy.
The tolerability of both applied immunotherapy protocols was good: there were no anaphylactic reactions observed or patients who prematurely discontinued participation in the study. The final analysis of the data revealed no significant differences in median survival values of patients in each of the three groups. However, when analyzing the Karnofsky Performance Status in patients of group 2, it was found that it tended to improve.
The study shows that the proposed immunotherapy protocols are safe for clinical use and have the potential to improve the patient's life quality. However, these findings should be considered intermediate until the findings of multicenter randomized clinical trials with a larger number of patients are obtained.
Introduction
. Myeloid-derived suppressor cells (MDSCs) play an important role in restriction of the immune response and are associated with a poor prognosis in cancer. Mobilization of hematopoietic ...stem cells (HSCs) before high-dose chemotherapy (HCT) with autologous HSC transplantation (auto-HSCT) is accompanied by a signifcant increase in MDSC counts in peripheral blood and apheresis product of multiple myeloma (MM) patients. However, quantitative changes of these cells at the post-transplant and their role at the immune recovery remain unexplored.
The study was aimed
to analyze the dynamics of circulating MDSC counts and the expression of suppressor molecule arginase-1 in patients with MM in the frst 12 months after HCT and auto-HSCT and evaluate association between MDSCs and transplantation outcomes.
Material and Methods
. The study included 44 MM patients who underwent HCT and auto-HSCT. The relative number of granulocytic MDSCs (G-MDSCs), monocytic MDSCs (M-MDSCs), and early-stage MDSCs (E-MDSCs), as well as the expression of arginase-1 in each of MDSC subsets was evaluated by fow cytometry in patient peripheral blood samples.
Results. At the engraftment (day +12 – +16, leukocytes >1×10
9
/l), M-MDSC relative count was increased (p
U
=0.038), as well as the relative (p
U
=0.003) and absolute (p
U
˂
0.0001) counts of G-MDSCs, decreasing after 6 months down to pre-transplant values (рU=0.007, рU=0.024 and рU=0.02, respectively) and remaining at the same level at the 12-month follow-up period. The absolute count of E-MDSCs by the time of the engraftment decreased transiently (p
U
=0.004 vs before HCT), gradually recovering by 12-month follow-up (p
U
=0.032 vs day +12 – +16). The remission within 12 months in the group with G-MDSCs˂0.17 % at the engraftment was observed in 67 ± 11 % of patients, with G-MDSCs >0.17 % – in 94 ± 6 % of patients (p=0.049). During the 12-month post-transplant, the number of M-MDSCs expressing arginase-1 has been increasing, with a tendency to lower values at the engraftment in patients with early MM relapse (p
U
=0.09).
Conclusion
. The association of early MM relapse after auto-HSCT with the lower count of G-MDSCs and the lower count of arginase-1
+
M-MDSCs at the engraftment suggests that MDSCs is involved in the restriction of homeostatic proliferation as a factor for more effective immune recovery.
Innate immune cells, including myeloid cells — myeloid derived suppressor cells (MDSCs) — are supposed to play an important role in the pathogenesis of axial spondyloarthritis (AxSp). Myeloid derived ...suppressor cells represent a heterogeneous population of immature cells capable of suppressing innate and adaptive immune responses with the most pronounced suppressor activity against T cells. Biological disease-modifying antirheumatic drugs (bDMARDs) can reduce the clinical and laboratory disease activity, but their effectiveness varies widely in different patients with AxSp. The present study is aimed at studying MDSCs subpopulations and their suppressive function depending on the response to bDMARD therapy in AxSp. The study included AxSp patients with a disease duration of 16.5 years (median); HLA-B27 (+) status was detected in 79% of cases. All patients received bDMARDs at least the past 12 weeks, including TNF inhibitors (etanercept, certolizumab pegol, adalimumab, or golimumab) or IL-17 inhibitors (secukinumab, ixekizumab, or netakimab). Percentage of granulocytic MDSCs (G-MDSCs, Lin
-
HLA-DR-CD33
+
CD66b
+
), monocytic MDSCs (M-MDSCs, HLA-DR
low/-
CD14
+
), MDSCs of early stage differentiation (E-MDSCs, Lin
-
HLA-DR
-
CD33
+
CD66b
-
), as well as intracellular expression of arginase-1 was assessed by flow cytometry. Frequency of circulating MDSC subpopulations of patients with a stable response to bDMARDs (responders) did not differ significantly compared to healthy donors. Patients not responding to bDMARDs therapy showed increased relative and absolute number of E-MDSCs compared to healthy donors (p
U
= 0.01 and p
U
= 0.02, respectively) and the responders (p
U
= 0.03 and p
U
= 0.07, respectively). Increased percentage of E-MDSCs was positively correlated to disease activity — ESR (R
s
= 0.821; p = 0.023), CRP (R
s
= 0.714; p = 0.07) and ASDAS
CRP
(R
s
= 0.829; p = 0.042) in the non-responder group. Responder patients exhibited no correlation between disease activity and circulating MDSCs. The suppressor potential of MDSCs was analyzed by the intracellular expression of arginase-1 molecule which is involved in the inhibition of T cell response. Patients with the stable response were characterized by increased expression of arginase-1 in E-MDSCs compared to donors (p
U
= 0.02). Non-responders did not demonstrate significant changes in Arg-1 expression, however, the percentage of arginase-1-expressing G-MDSCs was positively correlated to indexes ASDAS
ESR
(R
s
= 0.857; p = 0.014) and BASDAI (R
s
= 0.785; p = 0.036). Thus, E-MDSCs as well as arginase-1 expression in MDSCs may serve as biomarkers of effectiveness bDMARD therapy, and act as potential candidate predictors of response to therapy in AxSp.
Myeloid dendritic cells (DCs) play an important role in the immune response; therefore, the search for compounds that can effectively activate DCs is a needful goal. This study was aimed to ...investigate the effect of synthetic CpG oligodeoxynucleotides (CpG-ODN) on the maturation and allostimulatory activity of myeloid DCs in comparison with other PAMP and DAMP molecules. For the research, we synthesized known CpG-ODN class C (SD-101 and D-SL03) containing thiophosphate internucleotide groups, and their original phosphate-modified analogues (SD-101M and D-SL03M) with mesylphosphoramide internucleotide groups (M = μ-modification). The effects of CpG-ODN and other activators were evaluated on DCs generated from blood monocytes in the presence of GM-CSF and IFN-α (IFN-DC) or IL-4 (IL4-DC). Evaluation of the intracellular TLR-9 expression showed that both types of DCs (IFN-DC and IL4-DC) contained on average 52 and 80 % of TLR-9-positive cells, respectively. The CpG-ODNs studied enhanced the allostimulatory activity of IFN-DCs, and the effect of μ-modified CpG-ODNs was higher than that of CpG-ODNs with thiophosphate groups. The stimulating effect of CpG-ODN at a dose of 1.0 μg/ml was comparable (for D-SL03, D-SL03M, SD-101) with or exceeded (for SD-101M) the effect of LPS at a dose of 10 μg/ml. At the same time, IFN-DCs were characterized by greater sensitivity to the action of CpG-ODNs than IL4-DCs. The enhancement of DC allostimulatory activity in the presence of CpG-ODNs was associated with the induction of final DC maturation, which was confirmed by a significant decrease in the number of CD14+DC, an increase in mature CD83+DC and a trend towards an increase in CD86+DC. Interestingly, the characteristic ability of LPS to enhance the expression of the co-stimulatory molecule OX40L on DCs was revealed only for the μ-analogue SD-101M. In addition, CpG-ODNs (SD-101 and SD-101M) had a stimulatory effect on IFN-γ production comparable to the action of LPS. The data obtained indicate a stimulating effect of CpG-ODN on the maturation and allostimulatory activity of human myeloid DCs, which is more pronounced for μ-modified analogs.
Myeloid dendritic cells (DCs) play an important role in the immune response; therefore, the search for compounds that can effectively activate DCs is a needful goal. This study was aimed to ...investigate the effect of synthetic CpG oligodeoxynucleotides (CpG-ODN) on the maturation and allostimulatory activity of myeloid DCs in comparison with other PAMP and DAMP molecules. For the research, we synthesized known CpG-ODN class C (SD-101 and D-SL03) containing thiophosphate internucleotide groups, and their original phosphate-modified analogues (SD-101M and D- SL03M) with mesylphosphoramide internucleotide groups (M = μ-modification). The effects of CpG-ODN and other activators were evaluated on DCs generated from blood monocytes in the presence of GM-CSF and IFN-α (IFN-DC) or IL-4 (IL4-DC). Evaluation of the intracellular TLR-9 expression showed that both types of DCs (IFN-DC and IL4-DC) contained on average 52 and 80 % of TLR-9-positive cells, respectively. The CpG-ODNs studied enhanced the allostimulatory activity of IFN-DCs, and the effect of μ-modified CpG-ODNs was higher than that of CpG-ODNs with thiophosphate groups. The stimulating effect of CpG-ODN at a dose of 1.0 μg/ml was comparable (for D-SL03, D-SL03M, SD-101) with or exceeded (for SD-101M) the effect of LPS at a dose of 10 μg/ml. At the same time, IFN-DCs were characterized by greater sensitivity to the action of CpG-ODNs than IL4-DCs. The enhancement of DC allostimulatory activity in the presence of CpG-ODNs was associated with the induction of final DC maturation, which was confirmed by a significant decrease in the number of CD14+DC, an increase in mature CD83+DC and a trend towards an increase in CD86+DC. Interestingly, the characteristic ability of LPS to enhance the expression of the co-stimulatory molecule OX40L on DCs was revealed only for the μ-analogue SD-101M. In addition, CpG-ODNs (SD-101 and SD-101M) had a stimulatory effect on IFN-γ production comparable to the action of LPS. The data obtained indicate a stimulating effect of CpG-ODN on the maturation and allostimulatory activity of human myeloid DCs, which is more pronounced for μ-modified analogs.
The aim of the study
was to analyze the relationship between monocyte subpopulations and phenotype/ functions of monocyte-derived dendritic cells (DCs), as well as DC sensitivity to the tolerogenic ...effect of dexamethasone.
Materials and methods.
The study included 15 healthy donors. DCs were generated by cultivating enriched fractions of CD14+ monocytes with or without CD16+cell depletion (CD16-Mo-DCs or CD16+Mo-DCs, respectively) in the presence of interferon alpha (IFNα) and granulocyte-macrophage colony-stimulating factor (GM-CSF). Monocyte subpopulations were obtained by immunomagnetic negative selection.
Results.
CD16+Mo-DCs were characterized by higher percentage of mature (CD83+CD14-) and lower number of semi-mature (CD14+CD83+) cells, but were similar to CD16-Mo-DCs by HLA-DR and CD86 expression, involved in the presentation of antigens and activation of naive T-cells. and also to co-inhibitory/ tolerogenic molecules B7-H1 and TLR-2. CD16+Mo-DCs displayed higher allostimulatory activity, which was positively correlated with CD86 expression (
rS
= 0.69;
p
= 0.027) and negatively – with TLR-2 expression (
rS
= -0.72;
p
= 0.1). Allostimulatory activity of CD16-Mo-DCs was positively correlated with the number of mature CD14-CD83+DCs and semi-mature CD14+CD83+DCs. Addition of dexamethasone (10-6 M) into CD16-Mo-DCs and CD16+Mo-DCs cultures led to the delay of DC maturation, the decrease of CD86 and the increase of TLR-2 expression, as well as the increase of cells with co-inhibitory CD86- B7-H1+ phenotype that was positively correlated with the reduction of DC allostimulatory activity. The decrease of CD86+/TLR-2+ index in CD16+Mo-DC population was due to the reduction of CD86+DCs and in CD16-Mo-DC population – to the increase of TLR-2+cells. Dexamethasone possessed higher inhibitory effect on DC maturation in the CD16+Mo-DC cultures.
Conclusion.
CD14+ monocytes, both contained and depleted by CD16+ cells, can differentiate into DCs when cultured with IFNα. The presence of CD16+ cells in whole blood monocyte pool is associated with generation of DCs showed a more mature phenotype and higher allostimulatory activity. Both CD16- and CD16+ monocyte-derived DCs are sensitive to suppressive effect of dexamethasone. However, dexamethasone tolerogenic effect involves different mechanisms in CD16-Mo-DCs and CD16+Mo-DCs.
Expansion of myeloid-derived suppressor cells (MDSCs) due to impaired differentiation of myeloid progenitor cells under conditions of inflammation was described in a number of autoimmune diseases, ...including rheumatoid arthritis, systemic lupus erythematosus, and type 1 diabetes mellitus. Studying the role of MDSCs in ankylosing spondylitis is an important issue, given that increased concentration of proinflammatory mediators in this pathology can also cause myelopoiesis disorders. The aim of present work was to study the quantitative content of MDSC subpopulations in patients with different clinical phenotypes and activity of AS. 37 patients, including 10 patients without peripheral skeletal lesions (axial form) and 27 patients with simultaneous lesions of spine and peripheral joints (peripheral form) were recruited into the study. The control group consisted of 32 age/sex-related healthy donors. Evaluation of granulocytic (LinHLA-DRCD33+CD66b+; G-MDSC), monocytic (CD14+HLA-DRlow/-; M-MDSC) and early-stage MDSCs (LinHLA-DRCD33+CD66b- ; E-MDSC) was performed using corresponding antibodies (BD Biosciences, USA) in the population of peripheral blood mononuclear cells by flow cytometry. In general, the AS patients were characterized by an increased relative and absolute amount of M-MDSC (p = 0.00002 and p = 0.00003, respectively) and G-MDSC (p = 0.0002 and p = 0.0006, respectively). Patient gender, age, and HLA-B27 expression did not significantly affect the content of these cells in peripheral blood. An increase in the median values of M-MDSC was detected both in patients with axial (Ме 5.0 (3.2-6.3) versus 2.4 (1.7-3.5) %; p = 0.001) and peripheral form (Ме 5.0 (3.0-7.0) versus 2.4 (1.7-3.5) %; p = 0.0002) AS. At the same time, the G-MDSC expansion was observed only in patients with involvement of peripheral joints (Ме 0.16 (0.07-0.3) % versus 0.05 (0.04-0.09) %; p = 0.0001). The relative contents of E-MDSC, M-MDSC and G-MDSC in the axial form of AS was in direct correlation with the activity of the disease (R = 0.58, p = 0.02; R = 0.73, p = 0.08 and R = 0.65 p = 0.04, respectively). This relationship was not observed in peripheral form of AS. The data obtained suggest a potential involvement of MDSCs in pathogenesis and phenotypic heterogeneity of AS. Simultaneously, the revealed direct correlation between the MDSC contents and the disease activity suggests a decrease in suppressive activity and/or appearance of pro-inflammatory activity in MDSC, thus requiring further research in the field.
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