Myeloid-derived suppressor cells (MDSCs) are important regulators of immune processes during sepsis in mice. However, confirming these observations in humans has been challenging due to the lack of defined preparation protocols and phenotyping schemes for MDSC subsets. Thus, it remains unclear how MDSCs are involved in acute sepsis and whether they have a role in the long-term complications seen in survivors. Here, we combined comprehensive flow cytometry phenotyping with unsupervised clustering using self-organizing maps to identify the three recently defined human MDSC subsets in blood from severe sepsis patients, long-term sepsis survivors, and age-matched controls. We demonstrated the expansion of monocytic M-MDSCs and polymorphonuclear PMN-MDSCs, but not early-stage (e)-MDSCs during acute sepsis. High levels of PMN-MDSCs were also present in long-term survivors many months after discharge, suggesting a possible role in sepsis-related complications. Altogether, by employing unsupervised clustering of flow cytometric data we have confirmed the likely involvement of human MDSC subsets in acute sepsis, and revealed their expansion in sepsis survivors at late time points. The application of this strategy in future studies and in the clinical/diagnostic context would enable rapid progress toward a full understanding of the roles of MDSC in sepsis and other inflammatory conditions.

• MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• monocyty imunologie   MeSH
• myeloidní supresorové buňky imunologie   MeSH
• průtoková cytometrie metody   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• sepse imunologie   MeSH
• shluková analýza MeSH
• zánět imunologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Myeloid-derived suppressor cells (MDSC) represent a heterogeneous group of immature myeloid cells with immunoregulatory function in cancer and autoimmune diseases. In humans, two subsets of MDSC were determined based on the characteristic surface markers, monocytic MDSC (M-MDSC) and granulocytic MDSC (G-MDSC). Expansion of MDSC has been reported in some murine models and patients with autoimmune diseases and their immune-suppressive properties were characterized. However, the exact role of MDSC in the pathogenesis of autoimmune diseases is more complex and/or controversial. In type 1 diabetes mellitus (T1D), the increased frequency of MDSC was found in the blood of T1D patients but their suppressor capacity was diminished. In our study, we assessed the role of M-MDSC in the pathogenesis of T1D and showed for the first time the increased frequency of M-MDSC not only in the blood of T1D patients but also in their at-risk relatives compared to healthy donors. T1D patients with inadequate long term metabolic control showed an elevation of M-MDSC compared to patients with better disease control. Furthermore, we described the positive correlation between the percentage of M-MDSC and Th17 cells and IFN-γ producing T cells in T1D patients and their at-risk relatives. Finally, we found that the ability of M-MDSC to suppress autologous T cells is efficient only at the high MDSC: T cells ratio and dependent on cell-cell-contact and TGF-β production. Our data show that the engagement of MDSC in the pathogenesis of T1D is evident, yet not entirely explored and more experiments are required to clarify whether MDSC are beneficial or harmful in T1D.

• MeSH
• buňky Th17 imunologie   MeSH
• diabetes mellitus 1. typu krev   imunologie   MeSH
• dítě MeSH
• interferon gama metabolismus   MeSH
• lidé MeSH
• mladiství MeSH
• myeloidní supresorové buňky imunologie   MeSH
• počet CD4 lymfocytů MeSH
• regulační T-lymfocyty imunologie   MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Východiska: Myeloidní supresorové buňky (MDSCs) přispívají k úniku nádoru imunitní kontrole a podporují nádorový růst produkcí růstových faktorů. Zaměřili jsme se na klinické a analytické otázky týkající se MDSCs jako potenciálních biomarkerů a imunitních regulátorů, které se podílejí na progresi nádoru. Soubor pacientů a metody: Analyzovali jsme skupinu 10 pacientů s pokročilým kolorektálním karcinomem (colorectal carcinoma - CRC) a přítomnými metastázami (podskupina M1), nebo bez metastáz (podskupina M0) v době diagnózy. Krev byla pacientům odebrána v době diagnózy před zahájením protinádorové léčby a dále 12 měsíců po zahájení léčby. Fluorescenční imunoanalýzou na průtokovém cytometru byly detekovány subpopulace MDSCs - monocytární MDSC (M-MDSCs) s imunofenotypem CD45+ CD11b+ CD33+ HLA-DRlow/-CD14+ CD15- a granulocytární MDSC (CD33hi PMN-MDSC) s imunofenotypem CD45+ CD11b+ CD33hi HLA-DRlow/- CD14- CD15+. V preanalytické a analytické části studie byly změřeny náhodně vybrané vzorky krve pacientů s onkologickou diagnózou. Výsledky: Hladina cirkulujících M-MDSCs není asociována s metastatickým CRC. Naopak cirkulující CD33hi PMN-MDSCs byly zvýšeny u pacientů se vzdálenými metastázami (M1) v porovnání s T3 M0 podskupinou. Cirkulující M-MDSCs byly zvýšeny po podání chemoterapeutické léčby u 9 z 10 pacientů. CD33hi PMN-MDSCs značně poklesly po zahájení léčby u 5 z 10 pacientů a byly zvýšeny u 2 z 10 pacientů. Absolutní a relativní počty MDSCs spolu korelovaly a oba mohou být použity pro kvantifikaci MDSCs. Variační koeficient (CV) opakovatelnosti byl 6-11 % pro M-MDSCs a 25-44 % pro CD33hi PMN-MDSCs. CV mezilehlé preciznosti byl vyšší - 8-22 % u M-MDSCs a 35-79 % u CD33hi PMN-MDSCs, což ukazuje, že časová prodleva měření MDSCs ve vzorku plné krve ovlivňuje množství detekovaných MDSCs. Závěr: Kvantifikace subpopulací MDSC je závislá na typu zkoumaného vzorku a jeho preanalytickém zpracování. Explorativní analýza M-MDSCs a CD33hi PMN-MDSCs u pacientů s CRC ukázala, že dynamika cirkulujících MDSCs před a po podání protinádorové léčby je odlišná s ohledem na konkrétní subset myeloidních supresorových buněk.

Background: Myeloid-derived suppressor cells (MDSCs) contribute to tumor escape from host immune surveillance and to tumor progression by producing tumor-promoting factors. We focused on clinical and analytical MDSCs-related issues as potential biomarkers and immune regulators involved in tumor progression. Patients and Methods: We analyzed 10 patients with advanced colorectal carcinoma (CRC) with (M1 subgroup) or without (M0 subgroup) distant metastases at diagnosis. Peripheral blood was collected at diagnosis prior to treatment and subsequently 12 months after therapy initiation. Using multicolor flow cytometry MDSC subsets were evaluated. Monocytic MDSCs (M-MDSCs) were detected as CD45+ CD11b+ CD33+ HLA-DRlow/- CD14+ CD15- granulocytic MDSCs (CD33hi PMN-MDSC) were detected as CD45+ CD11b+ CD33hi HLA-DRlow/- CD14- CD15+. For analytical and preanalytical studies, random fresh blood specimens predominantly from cancer patients were analyzed. Results: Levels of circulating M-MDSCs were not associated with metastatic disease within advanced CRC patients. Levels of circulating CD33hi PMN-MDSCs were elevated in patients with distant metastases compared to T3 M0 subgroup. Circulating M-MDSCs increased upon treatment initiation in 9 out of 10 patients. CD33hi PMN-MDSCs substantially dropped upon treatment initiation in 5 out of 10 patients and substantially increased in 2 out of 10 patients. Analytical part showed that absolute and relative counts within each MDSC subset are correlated. Coefficient of variation (CV) for repeatability was 6-11% for M-MDSCs and 25-44% for CD33hi PMN-MDSCs. CV for reproducibility was higher with 8-22% for M-MDSCs and 35-79% for CD33hi PMN-MDSCs demonstrating that delay in measurement of MDSCs in whole blood specimen may distort quantification of circulating MDSC subsets. Conclusion: The quantification of MDSC subsets is substantially dependent on the type of specimen examined and its preanalytical processing. Exploratory analysis of M-MDSCs and CD33hi PMN-MDSCs in CRC patients revealed different dynamics of M-MDSC and CD33hi PMN-MDSC subsets in the context anti-cancer treatment.

• MeSH
• klinická studie jako téma MeSH
• kolorektální nádory * krev   patofyziologie   MeSH
• lidé MeSH
• metastázy nádorů MeSH
• myeloidní supresorové buňky * MeSH
• nádorové biomarkery MeSH
• odběr vzorku krve metody   MeSH
• průtoková cytometrie metody   MeSH
• Check Tag
• lidé MeSH

Myeloid-derived suppressor cells (MDSC) play an important role in tumor escape from antitumor immunity. MDSC accumulate in the lymphoid organs and blood during tumor growth and their mobilization was also reported after cyclophosphamide (CY) administration. In this communication, spleen MDSC accumulating after CY therapy (CY-MDSC) were compared with those expanded in mice bearing human papilloma viruses 16-associated TC-1 carcinoma (TU-MDSC). Although both CY-MDSC and TU-MDSC accelerated growth of TC-1 tumors in vivo, their phenotype and immunosuppressive function differed. CY-MDSC consisted of higher percentage of monocyte-like subpopulation and this was accompanied by lower relative expression of immunosuppressive genes and lower suppression of T-cell proliferation. After interferon-γ stimulation, the expression of immunosuppressive genes increased, but the suppressive ability of CY-MDSC did not reach that of TU-MDSC. The phenotype and function of MDSC obtained from mice bearing TC-1 tumors treated with CY was, in general, found to lie between CY-MDSC and TU-MDSC. After in vitro cultivation of MDSC in the presence of interleukin 12 (IL-12), the percentage of CD11b+/Gr-1+ cells decreased and was accompanied by an increase in the percentage of CD86+/MHCII+ cells. The strongest modulatory effect was noticed in the group of CY-MDSC. The susceptibility of CY-MDSC to all-trans-retinoic acid (ATRA) was also evaluated. In vitro cultivation with ATRA resulted in MDSC differentiation, and ATRA inhibited MDSC accumulation induced by CY administration. Our findings identified differences between CY-MDSC and TU-MDSC and supported the rationale for utilization of ATRA or IL-12 to alter MDSC accumulation after CY chemotherapy with the aim to improve its antitumor effect.

• MeSH
• aktivace lymfocytů MeSH
• antigeny CD11b biosyntéza   imunologie   MeSH
• antigeny CD86 biosyntéza   imunologie   MeSH
• buněčná diferenciace účinky léků   MeSH
• cyklofosfamid farmakologie   MeSH
• experimentální nádory imunologie   patologie   virologie   MeSH
• interferon gama farmakologie   MeSH
• interleukin-12 farmakologie   MeSH
• lidé MeSH
• lidský papilomavirus 16 imunologie   MeSH
• myeloidní buňky účinky léků   imunologie   patologie   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• proliferace buněk účinky léků   MeSH
• protinádorové látky farmakologie   MeSH
• regulace genové exprese u nádorů MeSH
• slezina účinky léků   imunologie   patologie   MeSH
• T-lymfocyty účinky léků   imunologie   patologie   MeSH
• transplantace nádorů MeSH
• tretinoin farmakologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Myeloid-derived suppressor cells (MDSCs) have been shown to contribute to tumor escape from host immune surveillance and to cancer progression by production of tumor-promoting soluble factors. Granulocyte colony-stimulating factor (G-CSF) is a principle cytokine controlling granulocyte number. Recombinant human G-CSF (rhG-CSF) has become the main therapeutic agent for the treatment of neutropenia and prophylaxis of febrile neutropenia in cancer patients. However, we show here that rhG-CSF triggers accumulation of granulocytic and monocytic subsets. Consequently, we discuss the pharmacological use of granulopoiesis stimulating factors not only in the context of febrile neutropenia but also from the perspective of MDSC-dependent and MDSC-independent mechanisms of immunosuppression and cancer angiogenesis.

• MeSH
• faktor stimulující kolonie granulocytů metabolismus   terapeutické užití   MeSH
• imunologická tolerance MeSH
• lidé MeSH
• myeloidní supresorové buňky imunologie   metabolismus   patologie   MeSH
• nádorová transformace buněk genetika   imunologie   metabolismus   MeSH
• nádory farmakoterapie   imunologie   metabolismus   MeSH
• protinádorové látky terapeutické užití   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Common variable immunodeficiency disorders (CVID) represent a group of primary immunodeficiency diseases characterized by hypogammaglobulinemia and impaired specific Ab response, resulting in recurrent infections due to dysfunctional immune response. The specific mechanisms mediating immune deficiency in CVID remain to be determined. Previous studies indicated that immune dysregulation in CVID patients is associated with chronic microbial translocation, systemic immune activation, and altered homeostasis of lymphocytic and myeloid lineages. A detailed phenotypic, functional characterization of plasma markers and immune cell populations was performed in 46 CVID patients and 44 healthy donors. CVID patients displayed significantly elevated plasma levels of a marker of neutrophil activation neutrophil gelatinase-associated lipocalin. Neutrophils from CVID patients exhibited elevated surface levels of CD11b and PD-L1 and decreased levels of CD62L, CD16, and CD80, consistent with a phenotype of activated neutrophils with suppressive properties. Neutrophils from CVID patients actively suppressed T cell activation and release of IFN-γ via the production of reactive oxygen species. Furthermore, CVID was associated with an increased frequency of low-density neutrophils (LDNs)/granulocytic myeloid-derived suppressor cells. LDN/granulocytic myeloid-derived suppressor cell frequency in CVID patients correlated with reduced T cell responsiveness. Exogenous stimulation of whole blood with bacterial LPS emulated some but not all of the phenotypic changes observed on neutrophils from CVID patients and induced neutrophil population with LDN phenotype. The presented data demonstrate that neutrophils in the blood of CVID patients acquire an activated phenotype and exert potent T cell suppressive activity. Specific targeting of myeloid cell-derived suppressor activity represents a novel potential therapeutic strategy for CVID.

• MeSH
• aktivace neutrofilů MeSH
• antigeny CD11b metabolismus   MeSH
• antigeny CD274 metabolismus   MeSH
• běžná variabilní imunodeficience imunologie   MeSH
• dospělí MeSH
• granulocyty fyziologie   MeSH
• imunologická tolerance MeSH
• kultivované buňky MeSH
• lidé středního věku MeSH
• lidé MeSH
• lipokalin-2 krev   MeSH
• mladý dospělý MeSH
• myeloidní supresorové buňky fyziologie   MeSH
• neutrofily fyziologie   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• T-lymfocyty imunologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• dospělí MeSH
• faktor stimulující kolonie granulocytů farmakologie   MeSH
• kolorektální nádory * krev   metabolismus   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• myeloidní supresorové buňky * cytologie   metabolismus   MeSH
• nádory prsu * farmakoterapie   krev   metabolismus   MeSH
• neparametrická statistika MeSH
• progrese nemoci MeSH
• rekombinantní proteiny farmakologie   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• práce podpořená grantem MeSH

Myeloid-derived suppressor cells (MDSC) are a heterogeneous group of immature myeloid cells that exist at very low numbers in healthy subjects but can expand significantly in malignant, infectious, and chronic inflammatory diseases. These cells are characterized as early-MDSCs, monocytic-MDSCs, and polymorphonuclear-MDSCs and can be studied on the basis of their immunophenotypic characteristics and their functional properties to suppress T-cell activation and proliferation. MDSCs have emerged as important contributors to tumor expansion and chronic inflammation progression by inducing immunosuppressive mechanisms, angiogenesis and drug resistance. Most experimental and clinical studies concerning MDSCs have been mainly focused on solid tumors. In recent years, however, the implication of MDSCs in the immune dysregulation associated with hematologic malignancies, immune-mediated cytopenias and allogeneic hemopoietic stem cell transplantation has been documented and the potential role of these cells as biomarkers and therapeutic targets has started to attract a particular interest in hematology. The elucidation of the molecular and signaling pathways associated with the generation, expansion and function of MDSCs in malignant and immune-mediated hematologic diseases and the clarification of mechanisms related to the circulation and the crosstalk of MDSCs with malignant cells and other components of the immune system are anticipated to lead to novel therapeutic strategies. This review summarizes all available evidence on the implication of MDSCs in hematologic diseases highlighting the challenges and perspectives arising from this novel field of research.

• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Myeloid cells comprise a major component of the tumor microenvironment (TME) that promotes tumor growth and immune evasion. By employing a small-molecule inhibitor of glutamine metabolism, not only were we able to inhibit tumor growth, but we markedly inhibited the generation and recruitment of myeloid-derived suppressor cells (MDSCs). Targeting tumor glutamine metabolism led to a decrease in CSF3 and hence recruitment of MDSCs as well as immunogenic cell death, leading to an increase in inflammatory tumor-associated macrophages (TAMs). Alternatively, inhibiting glutamine metabolism of the MDSCs themselves led to activation-induced cell death and conversion of MDSCs to inflammatory macrophages. Surprisingly, blocking glutamine metabolism also inhibited IDO expression of both the tumor and myeloid-derived cells, leading to a marked decrease in kynurenine levels. This in turn inhibited the development of metastasis and further enhanced antitumor immunity. Indeed, targeting glutamine metabolism rendered checkpoint blockade-resistant tumors susceptible to immunotherapy. Overall, our studies define an intimate interplay between the unique metabolism of tumors and the metabolism of suppressive immune cells.

• MeSH
• buněčná imunita * MeSH
• experimentální nádory imunologie   patologie   terapie   MeSH
• glutamin imunologie   MeSH
• imunoterapie MeSH
• makrofágy imunologie   patologie   MeSH
• myeloidní supresorové buňky imunologie   patologie   MeSH
• myši inbrední BALB C MeSH
• myši knockoutované MeSH
• myši MeSH
• nádorové mikroprostředí imunologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

• MeSH
• lidé MeSH
• myelodysplastické syndromy * etiologie   patofyziologie   MeSH
• myeloidní supresorové buňky * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• přehledy MeSH