Objective To investigate how culture duration affects the expression of immune membrane proteins in human monocyte-derived dendritic cells (DCs) and their exosomes (DEXs). Methods Human monocytes were induced with recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 4 (IL-4) to differentiate into DCs and were subsequently matured with tumor necrosis factor α(TNF-α). Exosomes were isolated by ultracentrifugation, and DEXs were identified by transmission electron microscopy and Amnis imaging flow cytometry, which were also used to quantify the expression of immune membrane proteins on DCs and DEXs. Results On the 10th day of culture, DCs displayed high surface expression of CD11c, CD80, CD86, major histocompatibility complex class I (MHC-I), and MHC-II. Expression peaked at day 18(CD11c: 78.66%±20.33%, CD80: 76.41%±10.02%, CD86: 96.43%±0.43%, MHC-I: 84.71%±2.96%, MHC-II: 80.01%±7.03%). After day 24, the overall expression showed a declining trend, with statistically significant differences observed for all markers except CD80 and MHC-II. By day 30, 80% of the DCs still expressed CD80, CD86, and MHC-II. The expression of immune membrane proteins on DEX surfaces also reached its peak on day 18, followed by an overall decline with prolonged culture time, with statistically significant differences observed for all markers except CD80. Correlation analysis revealed a significant positive relationship between the expression levels of immune membrane proteins on DC and DEX surfaces (CD11c: r=0.98; CD80: r=0.65; CD86: r=0.82; MHC-I: r=0.86; MHC-II: r=0.93). Conclusion Human monocyte-derived DCs in vitro express high expression of immune membrane proteins and maintain stable expression over a specific period. The exosomes secreted by these cells similarly demonstrate high surface expression of immune membrane proteins, with temporal trends aligned with those of the parent DCs.
Humans ; Dendritic Cells/immunology* ; Exosomes/immunology* ; Monocytes/metabolism* ; Cells, Cultured ; Time Factors ; B7-1 Antigen/metabolism* ; Membrane Proteins/immunology* ; Cell Culture Techniques/methods* ; B7-2 Antigen/metabolism* ; Cell Differentiation ; CD11c Antigen/metabolism* ; Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology*

OBJECTIVES: To investigate the expression of soluble factor-related apoptosis ligand (sFasL) in peripheral blood and microRNA-147b (miR-147b) in monocytes in children with sepsis and their value in assessing prognosis. METHODS: A prospective study was conducted on 124 children with sepsis (sepsis group), 60 children with common infections (infection group), and 60 healthy children undergoing physical examinations (healthy control group). The independent risk factors for poor prognosis in children with sepsis were analyzed, and the value of serum sFasL and monocyte miR-147b in predicting poor prognosis in children with sepsis was assessed. RESULTS: The serum level of sFasL and the relative expression of miR-147b in monocytes were highest in the sepsis group, followed by the infection group and the healthy control group (P<0.05). The multivariate logistic regression analysis showed that the serum level of sFasL and the relative expression of miR-147b in monocytes were closely associated with the poor prognosis of children with sepsis (P<0.05). The receiver operating characteristic curve analysis showed that the combination of serum sFasL level and relative expression of miR-147b in monocytes had a larger area under the curve compared to each indicator alone in predicting the prognosis of children with sepsis (P<0.05). CONCLUSIONS There are significant increases in the level of sFasL in peripheral blood and the relative expression of miR-147b in monocytes in children with sepsis. The combined use of these two indicators has relatively high clinical value in assessing the prognosis of children with sepsis.
Humans ; Sepsis/diagnosis* ; MicroRNAs/blood* ; Male ; Female ; Monocytes/metabolism* ; Prognosis ; Child, Preschool ; Prospective Studies ; Child ; Infant ; TNF-Related Apoptosis-Inducing Ligand/blood* ; Logistic Models

Adenosine, a critical molecule regulating cellular function both inside and outside cells, is controlled by two human adenosine deaminases: ADA1 and ADA2. While ADA1 primarily resides in the cytoplasm, ADA2 can be transported to lysosomes within cells or secreted outside the cell. Patients with ADA2 deficiency (DADA2) often suffer from systemic vasculitis due to elevated levels of TNF-α in their blood. Monocytes from DADA2 patients exhibit excessive TNF-α secretion and differentiate into pro-inflammatory M1-type macrophages. Our findings demonstrate that ADA2 localizes to endolysosomes within macrophages, and its intracellular concentration decreases in cells secreting TNF-α. This suggests that ADA2 may function as a lysosomal adenosine deaminase, regulating TNF-α expression by the cells. Interestingly, pneumonia patients exhibit higher ADA2 concentrations in their bronchoalveolar lavage (BAL), correlating with elevated pro-inflammatory cytokine levels. Conversely, cord blood has low ADA2 levels, creating a more immunosuppressive environment. Additionally, secreted ADA2 can bind to apoptotic cells, activating immune cells by reducing extracellular adenosine levels. These findings imply that ADA2 release from monocytes during inflammation, triggered by growth factors, may be crucial for cell activation. Targeting intracellular and extracellular ADA2 activities could pave the way for novel therapies in inflammatory and autoimmune disorders.
Humans ; Adenosine Deaminase/deficiency* ; Monocytes/cytology* ; Cell Differentiation ; Intercellular Signaling Peptides and Proteins/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Biomarkers/metabolism* ; Macrophages/metabolism* ; Pneumonia/metabolism*

OBJECTIVE: To explore the mechanism of effects of total saponin fraction from Dioscorea Nipponica Makino (TSDN) on M1/M2 polarization of monocytes/macrophages and arachidonic acid (AA) pathway in rats with gouty arthritis (GA). METHODS: Seventy-two Sprague Dawley rats were randomly divided into 4 groups (n=18 in each): normal, model, TSDN at 160 mg/kg, and celecoxib at 43.3 mg/kg. Monosodium urate crystal (MSU) was injected into the rats' ankle joints to induce an experimental GA model. Blood and tissue samples were collected on the 3rd, 5th, and 8th days of drug administration. Histopathological changes in the synovium of joints were observed via hematoxylin and eosin (HE) staining. The expression levels of arachidonic acid (AA) signaling pathway were assessed via real-time polymerase chain reaction (qPCR) and Western blot. Flow cytometry was used to determine the proportion of M1 and M2 macrophages in the peripheral blood. An enzyme-linked immunosorbent assay (ELISA) was used to detect interleukine (IL)-1 β, tumor necrosis factor-alpha (TNF-α), IL-4, IL-10, prostaglandin E₂ (PGE₂), and leukotriene B4 (LTB4). RESULTS: HE staining showed that TSDN improved the synovial tissue. qPCR and Western blot showed that on the 3rd, 5th and 8th days of drug administration, TSDN reduced the mRNA and protein expressions of cyclooxygenase (COX)2, microsomal prostaglandin E synthase-1 derived eicosanoids (mPGES-1), 5-lipoxygenase (5-LOX), recombinant human mothers against decapentaplegic homolog 3 (Smad3), nucleotide-binding oligomerization domain-like receptor protein 3 (NALP3), and inducible nitric oxide synthase (iNOS) in rats' ankle synovial tissues (P<0.01). TSDN decreased COX1 mRNA and protein expression on 3rd and 5th day of drug administration and raised it on the 8th day (both P<0.01). It lowered CD68 protein expression on days 3 (P<0.01), as well as mRNA and protein expression on days 5 and 8 (P<0.01). On the 3rd, 5th, and 8th days of drug administration, TSDN elevated the mRNA and protein expression of Arg1 and CD163 (P<0.01). Flow cytometry results showed that TSDN decreased the percentage of M1 macrophages while increasing the percentage of M2 in peripheral blood (P<0.05 or P<0.01). ELISA results showed that on the 3rd, 5th, and 8th days of drug administration, TSDN decreased serum levels of IL-1 β, TNF-α, and LTB4 (P<0.01), as well as PGE₂ levels on days 3rd and 8th days (P<0.05 or P<0.01); on day 8 of administration, TSDN increased IL-4 serum levels and enhanced IL-10 contents on days 5 and 8 (P<0.05 or P<0.01). CONCLUSION The anti-inflammatory effect of TSDN on rats with GA may be achieved by influencing M1/M2 polarization through AA signaling pathway.
Rats ; Humans ; Animals ; Arthritis, Gouty/drug therapy* ; Monocytes/pathology* ; Interleukin-10/metabolism* ; Arachidonic Acid/pharmacology* ; Dioscorea/chemistry* ; Rats, Wistar ; Tumor Necrosis Factor-alpha/metabolism* ; Saponins/therapeutic use* ; Interleukin-4/metabolism* ; Leukotriene B4/pharmacology* ; Rats, Sprague-Dawley ; Macrophages ; Signal Transduction ; RNA, Messenger/metabolism*

Deficiencies in the clearance of peripheral amyloid β (Aβ) play a crucial role in the progression of Alzheimer's disease (AD). Previous studies have shown that the ability of blood monocytes to phagocytose Aβ is decreased in AD. However, the exact mechanism of Aβ clearance dysfunction in AD monocytes remains unclear. In the present study, we found that blood monocytes in AD mice exhibited decreases in energy metabolism, which was accompanied by cellular senescence, a senescence-associated secretory phenotype, and dysfunctional phagocytosis of Aβ. Improving energy metabolism rejuvenated monocytes and enhanced their ability to phagocytose Aβ in vivo and in vitro. Moreover, enhancing blood monocyte Aβ phagocytosis by improving energy metabolism alleviated brain Aβ deposition and neuroinflammation and eventually improved cognitive function in AD mice. This study reveals a new mechanism of impaired Aβ phagocytosis in monocytes and provides evidence that restoring their energy metabolism may be a novel therapeutic strategy for AD.
Animals ; Mice ; Alzheimer Disease ; Amyloid beta-Peptides ; Monocytes ; Cognition ; Energy Metabolism ; Phagocytosis

Deficits in the clearance of amyloid β protein (Aβ) by the peripheral system play a critical role in the pathogenesis of sporadic Alzheimer's disease (AD). Impaired uptake of Aβ by dysfunctional monocytes is deemed to be one of the major mechanisms underlying deficient peripheral Aβ clearance in AD. In the current study, flow cytometry and biochemical and behavioral techniques were applied to investigate the effects of polysaccharide krestin (PSK) on AD-related pathology in vitro and in vivo. We found that PSK, widely used in therapy for various cancers, has the potential to enhance Aβ uptake and intracellular processing by human monocytes in vitro. After administration of PSK by intraperitoneal injection, APP/PS1 mice performed better in behavioral tests, along with reduced Aβ deposition, neuroinflammation, neuronal loss, and tau hyperphosphorylation. These results suggest that PSK holds promise as a preventive agent for AD by strengthening the Aβ clearance by blood monocytes and alleviating AD-like pathology.
Alzheimer Disease/pathology* ; Amyloid beta-Peptides/metabolism* ; Amyloid beta-Protein Precursor/metabolism* ; Animals ; Cognition ; Disease Models, Animal ; Mice ; Mice, Transgenic ; Monocytes/pathology* ; Polysaccharides/therapeutic use* ; Proteoglycans

OBJECTIVE: To investigate the effects of dasatinib on the maturation of monocyte-derived dendritic cells (moDCs) derived from healthy donors (HDs) and chronic myelogenous leukemia (CML) patients. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from HDs (n=10) and CML patients (n=10) who had got the remission of MR4.5 with imatinib treatment. The generation of moDCs from PBMCs was completed after 7 days of incubation in DC I culture medium, and another 3 days of incubation in DC II culture medium with or without 25 nmol/L dasatinib. On the 10th day, cells were harvested and expression of molecules of maturation related marker were assessed by flow cytometry. The CD80⁺CD86⁺ cell population in total cells was gated as DCs in the fluorescence-activated cell storting (FACS) analyzing system, then the expression of CD83, CD40 or HLA-DR in this population was analyzed respectively. RESULTS: The proportion of CD80⁺CD86⁺ cells in total cells didn't show a statistical difference between HD group and patient group (89.46%±9.70% vs 87.39%±9.34%, P=0.690). Dasatinib significantly enhanced the expression of the surface marker CD40 (P=0.008) and HLA-DR (P=0.028) on moDCs derived from HDs compared with the control group, while the expression of CD83 on moDCs didn't show a significant difference between dasatinib group and the control group (P=0.428). Meanwhile, dasatinib significantly enhanced the expression of the surface marker CD40 (P=0.023), CD83 (P=0.038) and HLA-DR (P=0.001) on moDCs derived from patients compared with the control group. CONCLUSION For CML patients, the same high proportion of moDCs as HDs can be induced in vitro, which provides a basis for the application of DC-based immunotherapy strategy. Dasatinib at the concentration of 25 nmol/L can efficiently promote the maturation of moDCs derived from HDs and CML patients in vitro. Dasatinib shows potential as a DC adjuvant to be applied in DC-based immunotherapy strategies, such as DC vaccine and DC cell-therapy.
Cell Differentiation ; Cells, Cultured ; Dasatinib/pharmacology* ; Dendritic Cells ; HLA-DR Antigens/pharmacology* ; Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism* ; Leukocytes, Mononuclear ; Monocytes

OBJECTIVE: To examine the expression of chemokine receptor CCR10 on monocytes/macrophages in the joints of patients with rheumatoid arthritis (RA), and to investigate the role of chemokine CCL28 and its receptor CCR10 in the migration of RA monocytes and its mechanism. METHODS: The expression of CCR10 in synovial tissues from 8 RA patients, 4 osteoarthritis (OA) patients, and 4 normal controls was analyzed by immunohistochemistry, and cell staining was scored on a 0-5 scales. Flow cytometry was used to measure the percentage of CCR10 positive cells in CD14⁺ monocytes from peripheral blood of 26 RA patients and 20 healthy controls, as well as from synovial fluid of 15 RA patients. The chemotactic migration of monocytes from RA patients and healthy controls in response to CCL28 was evaluated using an in vitro Transwell system. Western blotting was conducted to assess phosphorylation of the extracellular signal-regulated kinase (ERK) and protein kinase B (Akt) pathways in RA monocytes upon CCL28 treatment. RESULTS: CCR10 was predominantly expressed in RA synovial lining cells and sublining macrophages, endothelial cells, and lymphocytes. CCR10 expression was significantly increased on lining cells and sublining macrophages in RA synovial tissue compared with OA and normal synovial tissue (both P < 0.01). The patients with RA had markedly elevated expression of CCR10 on peripheral blood CD14⁺ monocytes compared with the healthy controls [(15.6±3.0)% vs. (7.7±3.8)%, P < 0.01]. CCR10 expression on synovial fluid monocytes from the RA patients was (32.0±15.0)%, which was significantly higher than that on RA peripheral blood monocytes (P < 0.01). In vitro, CCL28 caused significant migration of CD14⁺ monocytes from peripheral blood of the RA patients and the healthy controls at concentrations ranging from 10-100 μg/L (all P < 0.01). The presence of neutralizing antibody to CCR10 greatly suppressed CCL28-driven chemotaxis of RA monocytes (P < 0.01). Stimulation of RA monocytes with CCL28 induced a remarkable increase in phosphorylation of ERK and Akt (both P < 0.05). ERK inhibitor (U0126) and phosphatidylinositol 3-kinase (PI3K) inhibitor (LY294002) strongly reduced the migration of RA monocytes in response to CCL28 (both P < 0.01). CONCLUSION RA patients had increased CCR10 expression on peripheral blood, synovial fluid, and synovial tissue monocytes/macrophages. CCL28 ligation to CCR10 promoted RA monocyte migration through activation of the ERK and PI3K/Akt signaling pathways. The CCL28-CCR10 pathway could participate in monocyte recruitment into RA joints, thereby contributing to synovial inflammation and bone destruction.
Humans ; Monocytes/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Endothelial Cells/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Arthritis, Rheumatoid ; Synovial Membrane ; Chemokines, CC/metabolism* ; Synovial Fluid ; Osteoarthritis ; Receptors, CCR10/metabolism*

Objective: To investigate the relationship between human cytomegalovirus (HCMV) infection and peripheral blood CD14 CD16 monocytes in the pathogenesis of coronary heart disease (CHD), and to elucidate the mechanism of pathogenesis in CHD by analyzing the correlation between infection, inflammation, and CHD, to provide a basis for the prevention, evaluation, and treatment of the disease. Methods: In total, 192 patients with CHD were divided into three groups: latent CHD, angina pectoris, and myocardial infarction. HCMV-IgM and -IgG antibodies were assessed using ELISA; CD14 CD16 monocytes were counted using a five-type automated hematology analyzer; mononuclear cells were assessed using fluorescence-activated cell sorting; and an automatic biochemical analyzer was used to measure the levels of triglyceride, cholesterol, high- and low-density lipoprotein cholesterols, lipoprotein, hs-CRp and Hcy. Results: The positive rates of HCMV-IgM and -IgG were significantly higher in the CHD groups than in the control group. HCMV infection affects lipid metabolism to promote immune and inflammatory responses. Conclusion HCMV infection has a specific correlation with the occurrence and development of CHD. The expression of CD14 CD16 mononuclear cells in the CHD group was increased accordingly and correlated with acute HCMV infection. Thus, HCMV antibody as well as peripheral blood CD14 CD16 mononuclear cells can be used to monitor the occurrence and development of CHD.
Angina Pectoris ; epidemiology ; virology ; China ; epidemiology ; Coronary Disease ; epidemiology ; virology ; Cytomegalovirus ; physiology ; Cytomegalovirus Infections ; complications ; Humans ; Incidence ; Inflammation ; epidemiology ; etiology ; Leukocyte Count ; Monocytes ; metabolism ; Myocardial Infarction ; epidemiology ; virology

OBJECTIVE: To investigate the role and mechanism of Ly6C^high monocyte in mice with ventilator-induced lung injury (VILI). METHODS: Forty-eight healthy male SPF C57BL/6 mice were divided into spontaneous breathing group (n = 8), normal tidal volume (VT) group (VT was 8 mL/kg, n = 8), and high VT group (VT was 20 mL/kg, n = 32). The mice in the high VT group were subdivided into 1, 2, 3 and 4 hours subgroups, with 8 mice in each subgroup. All mice underwent direct tracheal intubation, those in the spontaneous breathing group maintained spontaneous breathing, and those in the normal VT group and high VT group were mechanically ventilated with different VT. After ventilation for 4 hours, bronchoalveolar lavage fluid (BALF) was collected to determine total protein, and the levels of inflammatory factors including tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were determined by enzyme-linked immune sorbent assay (ELISA). The lung tissues were harvested to determine the wet/dry (W/D) ratio, and lung tissue injury was assessed in terms of lung histopathologic examination after hematoxylin-eosin (HE) staining under the light microscope. The protein expressions of monocyte chemotactic protein-1 (MCP-1) and CC-chemokine receptor 2 (CCR2) in lung tissues were determined by Western Blot. Flow cytometry was used to detect the proportion of Ly6C^high monocyte in lung tissue. RESULTS: The histopathology of lung tissue structures was normal in the spontaneous breathing group and the normal VT group. Inflammatory reaction began to appear at 2 hours of high VT ventilation, and inflammatory reaction was gradually aggravated with the time extension. Compared with the spontaneous breathing group, the total protein, TNF-α, and IL-1β levels in BALF, the lung W/D ratio and MCP-1 expression were increased from 2 hours of high VT ventilation [total protein in BALF (g/L): 1.05±0.13 vs. 0.58±0.11, TNF-α in BALF (ng/L): 116.86±16.14 vs. 38.27±8.00, IL-1β in BALF (ng/L): 178.98±10.41 vs. 117.56±23.40, lung W/D ratio: 5.76±0.27 vs. 4.98±0.39, MCP-1/GAPDH: 0.87±0.19 vs. 0.29±0.12, all P < 0.05], and CCR2 expression and the proportion of Ly6C^high monocyte was significantly increased from 3 hours of high VT ventilation [CCR2/GAPDH: 0.84±0.19 vs. 0.24±0.11, Ly6C^high monocyte proportion: (9.01±2.47)% vs. (1.06±0.35)%, both P < 0.05], and they all showed an increased tendency with the time extension. There was no significant difference in the parameters mentioned above among the spontaneous breathing group, normal VT group and high VT ventilation 1-hour group. CONCLUSIONS Ly6C^high monocytes are involved in VILI, which aggravate VILI by activating the MCP-1/CCR2 axis.
Animals ; Antigens, Ly/metabolism* ; Lung ; Male ; Mice ; Mice, Inbred C57BL ; Monocytes ; Rats ; Rats, Sprague-Dawley ; Tidal Volume ; Tumor Necrosis Factor-alpha ; Ventilator-Induced Lung Injury