The effectiveness of early systemic inflammatory indices in predicting advanced intraventricular hemorrhage in preterm infants.

Some systemic inflammatory indices have been reported to be associated with intracerebral hemorrhage in adults. However, the relationship between systemic inflammatory indices and intraventricular hemorrhage (IVH) in premature neonates is still not completely understood. OBJECTIVE: To evaluate the relationship between systemic inflammatory indices obtained on the first day of life in premature infants and the development of severe IVH. PATIENTS AND METHOD: Premature newborns < 32 weeks of gestational age were included. Eligible patients were divided into 2 groups: Group 1: without IVH or grade I and II hemorrhage, and Group 2: grade III and IV HIV. Demographic characteristics, clinical outcomes, monocyte-to-lymphocyte ratio (MLR), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune inflammation index (SII), pan-immune inflammation value (PIV), and Systemic inflammation response index (SIRI) were compared between groups. RESULTS: A total of 1176 newborns were included in the study, 1074 in Group 1 and 102 premature babies in Group 2. There was no difference between the groups in terms of the count of leukocytes, neutrophils, monocytes, lymphocytes and platelets (p > 0.05). The values of NLR, MLR, PLR, PIV, SII and SIRI were similar in both groups (p > 0.05). CONCLUSION: While the relationship between inflammation, hemodynamics and IVH is still under discussion, our results show that systemic inflammatory indices have no predictive value for IVH.

Distinct maturation, glucose metabolism, and inflammatory function of human monocytes-derived IDECs mediated by anti-IgE and Pam3CSK4 alone or in combination.

Background: Cell energy metabolism controls the activation and function of dendritic cells (DCs). Inflammatory dendritic epidermal cells (IDECs) in skin lesions of atopic dermatitis (AD) express high-affinity IgE receptor (FcϵRI) and toll-like receptor 2 (TLR2), which mediate the generation and maintenance of inflammation. However, cellular energy metabolism and effector function of IDECs mediated by FcϵRI and TLR2 have not been fully elucidated. Methods: IDECs in vitro were treated with TLR2 agonist Pam3CSK4 and anti-IgE alone or in combination for 24 h. Further, we analyzed the expression of cell surface activation markers, production of inflammatory factors, and cellular energy metabolism profiles of IDECs by using flow cytometry, multiplex assay, RNA sequencing, targeted energy metabolism, and seahorse assays. Results: Compared to the unstimulated or anti-IgE groups, Pam3CSK4 alone or combined with anti-IgE groups significantly increased the expression of CD80, CD83, and CD86 on IDECs, but did not affect the expression of the above markers in the anti-IgE group. The release of inflammatory cytokines increased in the Pam3CSK4 alone or combined with anti-IgE groups, while there was a weak increasing trend in the anti-IgE group. The glycolysis/gluconeogenesis pathway of carbon metabolism was affected in all treatment groups. Furthermore, compared to the control group, we found a decrease in pyruvic acid, upregulation of PFKM, downregulation of FBP1, and increase in extracellular lactate, glycolysis rate, and glycolysis capacity after all treatments, while there was no difference between each treatment group. However, there was no difference in glycolytic reserve and mitochondrial basic and maximum respiration among all groups. Conclusion: Our results indicate that glycolysis of IDECs may be activated through FcϵRI and TLR2 to upregulate inflammatory factors, suggesting that danger signals from bacteria or allergens might evoke an inflammatory response from AD through the glycolysis pathway.

The impact of CLDN18.2 expression on effector cells mediating antibody-dependent cellular cytotoxicity in gastric cancer.

Activating antibody-dependent cellular cytotoxicity (ADCC) by targeting claudin-18 isoform 2 (CLDN18.2) using zolbetuximab, a monoclonal antibody against CLDN18.2, has been considered a promising novel therapeutic strategy for gastric cancer (GC). However, the impact of CLDN18.2 expression on natural killer (NK) cells and monocytes/macrophages-crucial effector cells of ADCC-in GC has not been fully investigated. In the present study, we assessed the impact of CLDN18.2 expression on clinical outcomes, molecular features, and the frequencies of tumor-infiltrating NK cells and macrophages, as well as peripheral blood NK cells and monocytes, in GC by analyzing our own GC cohorts. The expression of CLDN18.2 did not significantly impact clinical outcomes of GC patients, while it was significantly and positively associated with Epstein-Barr virus (EBV) status and PD-L1 expression. The frequencies of tumor-infiltrating NK cells and macrophages, as well as peripheral blood NK cells and monocytes, were comparable between CLDN18.2-positive and CLDN18.2-negative GCs. Importantly, both CLDN18.2 expression and the number of tumor-infiltrating NK cells were significantly higher in EBV-associated GC compared to other molecular subtypes. Our findings support the effectiveness of zolbetuximab in CLDN18.2-positive GC, and offer a novel insight into the treatment of this cancer type, highlighting its potential effectiveness for CLDN18.2-positive/EBV-associated GC.

Tregs delivered post-myocardial infarction adopt an injury-specific phenotype promoting cardiac repair via macrophages in mice.

Regulatory T cells (Tregs) are key immune regulators that have shown promise in enhancing cardiac repair post-MI, although the mechanisms remain elusive. Here, we show that rapidly increasing Treg number in the circulation post-MI via systemic administration of exogenous Tregs improves cardiac function in male mice, by limiting cardiomyocyte death and reducing fibrosis. Mechanistically, exogenous Tregs quickly home to the infarcted heart and adopt an injury-specific transcriptome that mediates repair by modulating monocytes/macrophages. Specially, Tregs lead to a reduction in pro-inflammatory Ly6CHi CCR2+ monocytes/macrophages accompanied by a rapid shift of macrophages towards a pro-repair phenotype. Additionally, exogenous Treg-derived factors, including nidogen-1 and IL-10, along with a decrease in cardiac CD8+ T cell number, mediate the reduction of the pro-inflammatory monocyte/macrophage subset in the heart. Supporting the pivotal role of IL-10, exogenous Tregs knocked out for IL-10 lose their pro-repair capabilities. Together, this study highlights the beneficial use of a Treg-based therapeutic approach for cardiac repair with important mechanistic insights that could facilitate the development of novel immunotherapies for MI.

Preoperative Immune Cell Dysregulation Accompanies Ovarian Cancer Patients into the Postoperative Period.

Ovarian cancer (OC) poses a significant global health challenge with high mortality rates, emphasizing the need for improved treatment strategies. The immune system's role in OC progression and treatment response is increasingly recognized, particularly regarding peripheral blood mononuclear cells (PBMCs) and cytokine production. This study aimed to investigate PBMC subpopulations (T and B lymphocytes, natural killer cells, monocytes) and cytokine production, specifically interleukin-1 beta (IL-1ß), interleukin-4 (IL-4), interleukin-6 (IL-6), interleukin-10 (IL-10), interleukin-12 (IL-12), and tumor necrosis factor alpha (TNFα), in monocytes of OC patients both preoperatively and during the early postoperative period. Thirteen OC patients and 23 controls were enrolled. Preoperatively, OC patients exhibited changes in PBMC subpopulations, including decreased cytotoxic T cells, increased M2 monocytes, and the disbalance of monocyte cytokine production. These alterations persisted after surgery with subtle additional changes observed in PBMC subpopulations and cytokine expression in monocytes. Considering the pivotal role of these altered cells and cytokines in OC progression, our findings suggest that OC patients experience an enhanced pro-tumorigenic environment, which persists into the early postoperative period. These findings highlight the impact of surgery on the complex interaction between the immune system and OC progression. Further investigation is needed to clarify the underlying mechanisms during this early postoperative period, which may hold potential for interventions aimed at improving OC management.

Chronic HIV Infection Increases Monocyte NLRP3 Inflammasome-Dependent IL-1α and IL-1ß Release.

Antiretroviral treatment (ART) has converted HIV from a lethal disease to a chronic condition, yet co-morbidities persist. Incomplete immune recovery and chronic immune activation, especially in the gut mucosa, contribute to these complications. Inflammasomes, multi-protein complexes activated by innate immune receptors, appear to play a role in these inflammatory responses. In particular, preliminary data indicate the involvement of IFI16 and NLRP3 inflammasomes in chronic HIV infection. This study explores inflammasome function in monocytes from people with HIV (PWH); 22 ART-treated with suppressed viremia and 17 untreated PWH were compared to 33 HIV-negative donors. Monocytes were primed with LPS and inflammasomes activated with ATP in vitro. IFI16 and NLRP3 mRNA expression were examined in a subset of donors. IFI16 and NLRP3 expression in unstimulated monocytes correlated negatively with CD4 T cell counts in untreated PWH. For IFI16, there was also a positive correlation with viral load. Monocytes from untreated PWH exhibit increased release of IL-1α, IL-1ß, and TNF compared to treated PWH and HIV-negative donors. However, circulating monocytes in PWH are not pre-primed for inflammasome activation in vivo. The findings suggest a link between IFI16, NLRP3, and HIV progression, emphasizing their potential role in comorbidities such as cardiovascular disease. The study provides insights into inflammasome regulation in HIV pathogenesis and its implications for therapeutic interventions.

Prognostic value of inflammatory markers NLR, PLR, and LMR in gastric cancer patients treated with immune checkpoint inhibitors: a meta-analysis and systematic review.

Background: Immune checkpoint inhibitors (ICIs) represent a groundbreaking approach to cancer therapy. Inflammatory markers such as the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR) have emerged as potential indicators strongly associated with tumor prognosis, albeit their prognostic significance remains contentious. The predictive value of NLR, PLR, LMR in patients with gastric cancer (GC) treated with ICIs has not been fully explored; therefore, we conducted a meta-analysis to examine the potential of inflammatory markers NLR, PLR, and LMR as survival predictors in this population. Methods: A comprehensive search was conducted across PubMed, Embase, Web of Science, and Cochrane databases, with the search cut-off date set as March 2024. Hazard ratios (HR) and their corresponding 95% confidence intervals (CI) were calculated to assess the prognostic significance of NLR, PLR, and LMR for both progression-free survival (PFS) and overall survival (OS). Results: Fifteen cohort studies involving 1336 gastric cancer patients were finally included in this meta-analysis. The results of the meta-analysis showed that high levels of NLR were associated with poorer OS and PFS in GC patients receiving ICIs, with combined HRs of OS [HR=2.01, 95%CI (1.72,2.34), P<0.01], and PFS PFS[HR=1.59, 95%CI (1.37,1.86), P<0.01], respectively; high levels of PLR were associated with poorer OS and PFS, and the combined HR was OS [HR=1.57, 95%CI (1.25,1.96), P<0.01], PFS [HR=1.52,95%CI (1.20, 1.94), P<0.01], respectively; and there was an association between elevated LMR and prolonged OS and PFS, and the combined HR was OS [HR=0.62, 95%CI (0.47,0.81), P<0.01], and PFS [HR=0.69, 95%CI (0.50,0.95), P<0.01]. Conclusion: In gastric cancer (GC) patients treated with immune checkpoint inhibitors (ICIs), elevated neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were associated with poorer overall survival (OS) and progression-free survival (PFS), while high lymphocyte-to-monocyte ratio (LMR) was linked to improved OS and PFS. Subgroup analyses suggested that NLR might be particularly pertinent to the prognosis of GC patients. In conclusion, the inflammatory markers NLR, PLR, and LMR serve as effective biomarkers for prognostic assessment in GC patients, offering valuable insights for therapeutic decision-making in the realm of GC immunotherapy. Prospective studies of high quality are eagerly awaited to validate these findings in the future. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/#myprospero, identifier CRD42024524321.

Dysregulated cytokine and oxidative response in hyper-glycolytic monocytes in obesity.

Introduction: Obesity is associated with a plethora of health complications, including increased susceptibility to infections or decreased vaccine efficacy, partly due to dysregulated immune responses. Monocytes play a crucial role in innate immunity, yet their functional alterations in obesity remain poorly understood. Methods: Here, we employed proteomic and metabolomic analyses to investigate monocyte characteristics in individuals with overweight, obesity, impaired glucose tolerance (IGT), and type 2 diabetes (T2D), compared to lean donors. Results and discussion: Our results revealed distinct molecular signatures in monocytes from individuals with obesity, with significant alterations in pathways related to metabolism, cellular migration, and phagocytosis. Moreover, LPS-induced activation of monocytes unveiled heightened metabolic reprogramming towards glycolysis in subjects with obesity accompanied by dysregulated cytokine responses and elevated oxidative stress. Additionally, monocytes from donors with obesity exhibited increased lipid droplet accumulation. These findings shed light on the immunometabolic dysregulation underlying obesity-associated immune dysfunction, highlighting potential targets for therapeutic intervention.

Impaired Proliferation of CD8+ T Cells Stimulated with Monocyte-Derived Dendritic Cells Previously Matured with Thapsigargin-Stimulated LAD2 Human Mast Cells.

CD8+ T cells are essential for adaptive immunity against infection and tumors. Their ability to proliferate after stimulation is crucial to their functionality. Dendritic cells (DCs) are professional antigen-presenting cells that induce their proliferation. Here, we show that thapsigargin-induced LAD2 mast cell (MC) line-released products can impair the ability of monocyte-derived DCs to induce CD8+ T-cell proliferation and the generation of Th1 cytokine-producing T cells. We found that culture medium conditioned with LAD2 MCs previously stimulated with thapsigargin (thapsLAD2) induces maturation of DCs as determined by the maturation markers CD80, CD83, CD86, and HLA-DR. However, thapsLAD2-matured DCs produced no detectable TNFα or IL-12 during the maturation. In addition, although their surface expression of PD-L1 was comparable with the immature or TLR7/8-agonist (R848)-matured DCs, their TIM-3 expression was significantly higher than in immature DCs and even much higher than in R848-matured DCs. In addition, contrary to R848-matured DCs, the thapsLAD2-matured DCs only tended to induce enhanced proliferation of CD4+ T cells than immature DCs. For CD8+ T cells, this tendency was not even detected because thapsLAD2-matured and immature DCs comparably induced their proliferation, which contrasted with the significantly enhanced proliferation induced by R848-matured DCs. Furthermore, these differences were comparably recapitulated in the ability of the tested DCs to induce IFNγ- and IFNγ/TNFα-producing T cells. These findings show a novel mechanism of MC-mediated regulation of adaptive immune responses.

A subpopulation of human bone marrow erythroid cells displays a myeloid gene expression signature similar to that of classic monocytes.

Erythroid cells, serving as progenitors and precursors to erythrocytes responsible for oxygen transport, were shown to exhibit an immunosuppressive and immunoregulatory phenotype. Previous investigations from our research group have revealed an antimicrobial gene expression profile within murine bone marrow erythroid cells which suggested a role for erythroid cells in innate immunity. In the present study, we focused on elucidating the characteristics of human bone marrow erythroid cells through comprehensive analyses, including NanoString gene expression profiling utilizing the Immune Response V2 panel, a BioPlex examination of chemokine and TGF-beta family proteins secretion, and analysis of publicly available single-cell RNA-seq data. Our findings demonstrate that an erythroid cell subpopulation manifests a myeloid-like gene expression signature comprised of antibacterial immunity and neutrophil chemotaxis genes which suggests an involvement of human erythroid cells in the innate immunity. Furthermore, we found that human erythroid cells secreted CCL22, CCL24, CXCL5, CXCL8, and MIF chemokines. The ability of human erythroid cells to express these chemokines might facilitate the restriction of immune cells in the bone marrow under normal conditions or contribute to the ability of erythroid cells to induce local immunosuppression by recruiting immune cells in their immediate vicinity in case of extramedullary hematopoiesis.

An early regulatory mechanism of hyperinflammation by restricting monocyte contribution.

Innate immune cells play a key role in inflammation as a source of pro-inflammatory cytokines. However, it remains unclear how innate immunity-mediated inflammation is fine-tuned to minimize tissue damage and assure the host's survival at the early phase of systemic inflammation. The results of this study with mouse models demonstrate that the supply of monocytes is restricted depending on the magnitude of inflammation. During the acute phase of severe inflammation, monocytes, but not neutrophils, were substantially reduced by apoptosis and the remaining monocytes were dysfunctional in the bone marrow. Monocyte-specific ablation of Casp3/7 prevented monocyte apoptosis but promoted monocyte necrosis in the bone marrow, leading to elevated levels of pro-inflammatory cytokines and the increased mortality of mice during systemic inflammation. Importantly, the limitation of monocyte supply was dependent on pro-inflammatory cytokines in vivo. Consistently, a reduction of monocytes was observed in the peripheral blood during cytokine-release syndrome (CRS) patients, a pathogen-unrelated systemic inflammation induced by chimeric antigen receptor-T cell (CAR-T cell) therapy. Thus, monocytes act as a safety valve to alleviate tissue damage caused by inflammation and ensure host survival, which may be responsible for a primitive immune-control mechanism that does not require intervention by acquired immunity.

Summary data-based Mendelian randomization and single-cell RNA sequencing analyses identify immune associations with low-level LGALS9 in sepsis.

Sepsis is one of the major challenges in intensive care units, characterized by the complexity of the host immune status. To gain a deeper understanding of the pathogenesis of sepsis, it is crucial to study the phenotypic changes in immune cells and their underlying molecular mechanisms. We conducted Summary data-based Mendelian randomization analysis by integrating genome-wide association studies data for sepsis with expression quantitative trait locus data, revealing a significant decrease in the expression levels of 17 biomarkers in sepsis patients. Furthermore, based on single-cell RNA sequencing data, we elucidated potential molecular mechanisms at single-cell resolution and identified that LGALS9 inhibition in sepsis patients leads to the activation and differentiation of monocyte and T-cell subtypes. These findings are expected to assist researchers in gaining a more in-depth understanding of the immune dysregulation in sepsis.

Imbalance polarization of M1/M2 macrophages in miscarried uterus.

BACKGROUND: Lipopolysaccharides (LPS) is well known to manifest a miscarriage-inducing effector during early pregnancy and activate macrophage to induce M1 macrophage polarization. However, the role of macrophage polarization in LPS-related miscarriage-inducing effect is not apparent. METHODS: In this work, gene expression changes and the percentage of M1/M2 macrophages and monocytes in LPS-induced miscarried uterus were firstly analyzed by RNA sequencing (RNA-seq) and Flow Cytometry. To explore the origin that contributes to M1/M2 macrophage differentiation, the expression of monocyte chemotactic protein (MCP-1), CCL3, and CCL4, chemokines related to monocyte/macrophage migration, was tested by quantitative real time PCR (qRT-PCR). RESULTS: We found that percentage of M1 macrophages rose, while the percentage of M2 macrophages declined down in the injected mice uterus. Meanwhile, the percentage of M1 and M2 macrophages showed no significant difference in the spleens of LPS injected mice compared to PBS injected control mice. Expression of Mcp-1, Ccl3, and Ccl4 and numbers of monocytes were remarkably up-regulated in LPS-induced miscarried mice uterus. CONCLUSION: These results indicated that polarization and proportion changes of macrophage in the uterus may contribute to miscarriage. Our work provides new evidence correlating the aberrant regulation of M1/M2 macrophage polarization with deleterious miscarriage-inducing effects. This will help us understand the roles of critical immune cell differentiation in maintaining normal pregnancy.

Pan-immune-inflammation value and survival in patients with breast cancer from a Peruvian reference hospital.

The pan-immune-inflammation value (PIV), calculated as (neutrophil × platelet × monocyte)/lymphocyte count, may be useful for estimating survival in breast cancer patients. To determine the prognostic value of PIV for overall survival in breast cancer patients in Lima, Peru. A retrospective cohort study was conducted. 97 breast cancer patients diagnosed between January 2010 and December 2016 had their medical records analyzed. The primary dependent variable was overall survival, and the key independent variable was the PIV, divided into high (≥ 310) and low (< 310) groups. Patient data included demographics, treatment protocols and other clinical variables. Statistical analysis involved Kaplan-Meier survival curves and Cox proportional hazards modeling. Patients with a PIV ≥ 310 had significantly lower 5-year survival functions (p = 0.004). Similar significant differences in survival were observed for clinical stage III-IV (p = 0.015), hemoglobin levels < 12 mg/Dl (p = 0.007), histological grade (p = 0.019), and nuclear grade (p < 0.001); however, molecular classification did not show a significant survival difference (p = 0.371). The adjusted Hazard Ratios showed that PIV ≥ 310 was significantly associated with poor outcome (5.08, IC95%: 1.52-16.92). While clinical stage and hemoglobin levels were associated with survival in the unadjusted model. These factors did not maintain significance after adjustment. PIV is an independent predictor of reduced survival in Peruvian breast cancer patients.

IL-1R signaling drives enteric glia-macrophage interactions in colorectal cancer.

Enteric glia have been recently recognized as key components of the colonic tumor microenvironment indicating their potential role in colorectal cancer pathogenesis. Although enteric glia modulate immune responses in other intestinal diseases, their interaction with the colorectal cancer immune cell compartment remains unclear. Through a combination of single-cell and bulk RNA-sequencing, both in murine models and patients, here we find that enteric glia acquire an immunomodulatory phenotype by bi-directional communication with tumor-infiltrating monocytes. The latter direct a reactive enteric glial cell phenotypic and functional switch via glial IL-1R signaling. In turn, tumor glia promote monocyte differentiation towards pro-tumorigenic SPP1+ tumor-associated macrophages by IL-6 release. Enteric glia cell abundancy correlates with worse disease outcomes in preclinical models and colorectal cancer patients. Thereby, our study reveals a neuroimmune interaction between enteric glia and tumor-associated macrophages in the colorectal tumor microenvironment, providing insights into colorectal cancer pathogenesis.

Integrated analysis of single-cell sequencing and machine learning identifies a signature based on monocyte/macrophage hub genes to analyze the intracranial aneurysm associated immune microenvironment.

Monocytes are pivotal immune cells in eliciting specific immune responses and can exert a significant impact on the progression, prognosis, and immunotherapy of intracranial aneurysms (IAs). The objective of this study was to identify monocyte/macrophage (Mo/MΦ)-associated gene signatures to elucidate their correlation with the pathogenesis and immune microenvironment of IAs, thereby offering potential avenues for targeted therapy against IAs. Single-cell RNA-sequencing (scRNA-seq) data of IAs were acquired from the Gene Expression Synthesis (GEO) database. The significant infiltration of monocyte subsets in the parietal tissue of IAs was identified using single-cell RNA sequencing and high-dimensional weighted gene co-expression network analysis (hdWGCNA). The integration of six machine learning algorithms identified four crucial genes linked to these Mo/MΦ. Subsequently, we developed a multilayer perceptron (MLP) neural model for the diagnosis of IAs (independent external test AUC=1.0, sensitivity =100%, specificity =100%). Furthermore, we employed the CIBERSORT method and MCP counter to establish the correlation between monocyte characteristics and immune cell infiltration as well as patient heterogeneity. Our findings offer valuable insights into the molecular characterization of monocyte infiltration in IAs, which plays a pivotal role in shaping the immune microenvironment of IAs. Recognizing this characterization is crucial for comprehending the limitations associated with targeted therapies for IAs. Ultimately, the results were verified by real-time fluorescence quantitative PCR and Immunohistochemistry.

Anandamide modulation of monocyte-derived Langerhans cells: implications for immune homeostasis and skin inflammation.

Introduction: The endocannabinoid system (ECS), named after the chemical compounds found in the cannabis plant, is a regulatory network of neurotransmitters, receptors, and enzymes that plays crucial roles in skin health and disease. Endogenous ligands of the ECS, called endocannabinoids, have proven to be important regulators of immune responses. One of the most prevalent endocannabinoids, arachidonoylethanolamide (also known as anandamide), is known for its anti-inflammatory effects. Langerhans cells (LCs) are the sole antigen-presenting cells present in the human epidermis. They serve as the first line of defense against pathogens and are essential for the skin's specific immune responses and play a critical role in maintaining tissue homeostasis; however, little is known about the effect of endocannabinoids on these cells. Our research aimed to provide the connection between monocyte-derived Langerhans cells (moLCs) and the ECS, shedding light on their collaborative roles in immune homeostasis and inflammation. Methods: Human monocytes were differentiated into moLCs using established protocols. Anandamide was applied during the differentiation process to test its effect on the viability, marker expression, and cytokine production of the cells, as well as in short term treatments for intracellular calcium measurement. TLR ligands applied after the differentiation protocol were used to activate moLCs. The impact of anandamide on the functionality of moLCs was further assessed using differential gene expression analysis of bulk RNA-Seq data, moLC-T cell cocultures, while ELISpot was employed to determine polarization of T cells activated in the aforementioned cocultures. Results: Anandamide did not significantly affect the viability of moLCs up to 10 µM. When applied during the differentiation process it had only a negligible effect on CD207 expression, the prototypic marker of LCs; however, there was an observed reduction in CD1a expression by moLCs. Anandamide had no significant effects on the maturation status of moLCs, nor did it affect the maturation induced by TLR3 and TLR7/8 agonists. MoLCs differentiated in the presence of anandamide did however show decreased production of CXCL8, IL-6, IL-10 and IL-12 cytokines induced by TLR3 and TLR7/8 activation. Anandamide-treated moLCs showed an increased capability to activate naïve T cells; however, not to the level seen with combined TLR agonism. RNA sequencing analysis of moLCs differentiated with anandamide showed modest changes compared to control cells but did reveal an inhibitory effect on oxidative phosphorylation specifically in activated moLCs. Anandamide also promoted the polarization of naïve T cells towards a Th1 phenotype. Discussion: Our results show that anandamide has nuanced effects on the differentiation, maturation, cytokine secretion, metabolism and function of activated moLCs. Among these changes the decrease in CD1a expression on moLCs holds promise to selectively dampen inflammation induced by CD1a restricted T cells, which have been implicated as drivers of inflammation in common inflammatory skin conditions such as psoriasis, atopic dermatitis and contact dermatitis.

Uniform Suspension of Heat-Killed Staphylococcus aureus for a Positive Control Used in the Monocyte-Activation Test.

Pyrogens, classified as bacterial endotoxins and non-endotoxin pyrogens (NEPs), induce fever or shock when released into the bloodstream or spinal fluid. Recently, a monocyte-activation test (MAT) involving human cell culture has been developed to detect pyrogens in injectable products. To evaluate the sensitivity of MAT, a reference standard endotoxin was used as a positive control; however, the reactivity differed between the endotoxins and NEPs, necessitating positive controls for NEPs. This study aimed to explore a preparation method for heat-killed Staphylococcus aureus (HKSA) as a positive control for NEPs in MAT. Because S. aureus forms grape-like clusters, nine types of glass filters with pore sizes of 0.5-2.7 µm were evaluated to obtain a uniform bacterial suspension. The suspension was then heat-treated to kill the bacteria, resulting in HKSA samples. Serial dilutions of HKSA were tested by MAT using peripheral blood mononuclear cells. The interleukin-6 concentrations in the culture supernatant were measured by enzyme-linked immuno-sorbent assay to assess pyrogenic activities of HKSA. The pore sizes of the glass filters affected the uniformity of HKSA, and GF/C filter was selected for HKSA preparation. Repeated filtration improved uniformity, and a uniform suspension of HKSA was obtained through double filtration using a GF/C filter. Despite the decrease in HKSA activity as filtration frequency increased, the detection limit remained consistently unchanged. This suggests that repeated filtration can adjust the activity of HKSA to a baseline level and that a uniform suspension of HKSA exhibiting low variation is suitable as a positive control in MAT.

Proinflammatory Activation of Monocytes in Patients with Immunoinflammatory Rheumatic Diseases.

The pathogenesis of immunoinflammatory rheumatic diseases (IRDs) is based on chronic inflammation, one of the key mechanisms of which may be abnormal activation of macrophages, leading to further disruption of the immune system. OBJECTIVE: . The objective of this study was to evaluate the proinflammatory activation of circulating monocytes in patients with IRDs. MATERIALS AND METHODS: . The study involved 149 participants (53 patients with rheumatoid arthritis (RA), 45 patients with systemic lupus erythematosus (SLE), 34 patients with systemic scleroderma (SSc), and 17 participants without IRDs) 30 to 65 years old. Basal and lipopolysaccharide (LPS)-stimulated secretion of monocytes was studied in a primary culture of monocytes obtained from blood by immunomagnetic separation. Quantitative assessment of the cytokines tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), as well as the chemokine monocyte chemoattractant protein-1 (MCP-1) was carried out in the culture fluid by ELISA. Proinflammatory activation of monocytes was calculated as the ratio of LPS-stimulated and basal secretions. RESULTS: . It was shown that the basal secretion of all studied cytokines was significantly increased in all groups of patients with IRDs, except for the secretion of IL-1ß in the SLE group, compared to the control. LPS-stimulated secretion of TNF-α was increased and MCP-1 was decreased in patients with IRDs compared to the control group; LPS-stimulated IL-1ß secretion only in the SSc group significantly differed from the control group. In the RA group, monocyte activation was reduced for all cytokines compared to the control; in the SLE group, for TNF-α and MCP-1; in the SSc group, for MCP-1. CONCLUSIONS: . The decrease in proinflammatory activation of monocytes in patients with IRDs is due to a high level of basal secretion of cytokines, which can lead to disruption of the adequate immune response in these diseases and is an important link in the pathogenesis of chronic inflammation.

The Potential Role of the Leucocyte Immunoglobulin-Like Receptors in Kidney Transplant Rejection: A Mini Review.

Antibody-mediated rejection (ABMR) remains one of the main causes of long-term graft failure after kidney transplantation, despite the development of powerful immunosuppressive therapy. A detailed understanding of the complex interaction between recipient-derived immune cells and the allograft is therefore essential. Until recently, ABMR mechanisms were thought to be solely caused by adaptive immunity, namely, by anti-human leucocyte antigen (HLA) donor-specific antibody. However recent reports support other and/or additive mechanisms, designating monocytes/macrophages as innate immune contributors of ABMR histological lesions. In particular, in mouse models of experimental allograft rejection, monocytes/macrophages are readily able to discriminate non-self via paired immunoglobulin receptors (PIRs) and thus accelerate rejection. The human orthologs of PIRs are leukocyte immunoglobulin-like receptors (LILRs). Among those, LILRB3 has recently been reported as a potential binder of HLA class I molecules, shedding new light on LILRB3 potential as a myeloid mediator of allograft rejection. In this issue, we review the current data on the role of LILRB3 and discuss the potential mechanisms of its biological functions.