Higher Cytokine Concentrations Research Articles

Use of the CytoSorb adsorber in patients with acute-on-chronic liver failure.

CytoSorb is a hemoadsorptive column used to remove high concentrations of proinflammatory cytokines in septic shock. Data on CytoSorb application in acute-on-chronic liver failure (ACLF) is lacking. This retrospective observational study analyzed 21 ACLF patients admitted to ICUs at the Vienna General Hospital who received CytoSorb adsorber therapy between 2017 and 2023. Median ICU length of stay was 8days (IQR: 3-13), the ICU survival rate was 23.8% (n = 5). Significant decreases in bilirubin (median peak: 20.7mg/dL to median post-treatment: 10.8mg/dL; - 47.8%; p < 0.001), procalcitonin (1.34 to 0.74pg/mL; - 44.6%; p < 0.001), interleukin-6 (385 to 131ng/mL; - 66.0%; p = 0.0182)-but also of platelets (72 to 31 G/L; - 56.9%; p = 0.0014) and fibrinogen (230 to 154mg/dL; - 33.0%; p = 0.0297) were detected. ICU survivors had a trend towards a stronger relative decrease in bilirubin (- 76.1% vs. - 48.2%), procalcitonin (- 90.6% vs. - 23.5%), and IL-6 (- 54.6% vs. - 17.8%) upon CytoSorb treatment. Moreover, no serious CytoSorb-attributed complications were detected. In conclusion, use of CytoSorb adsorber in ACLF patients results in a significant decrease in bilirubin and proinflammatory cytokines, while platelets and fibrinogen were also lowered. Prospective trials are warranted to investigate the impact of CytoSorb on clinical outcomes of ACLF patients with high proinflammatory cytokine levels.

The role of inflammation and antithrombin supplementation on thromboelastographic parameters during veno-venous ECMO for respiratory failure.

Extracorporeal membrane oxygenation (ECMO) may act as a driver or propagator of systemic inflammation. In turn, cytokine release can modify thromboelastographic (TEG) tests which are commonly used for anticoagulation monitoring. In this context, antithrombin (AT) supplementation might further modify TEG. This is a pre-specified sub-study of the "Randomized Controlled Trial of Antithrombin Supplementation During Extracorporeal Membrane Oxygenation" study (investigator-initiated, randomized, single-blind, two-arm trial) conducted in two Italian ECMO referral ICUs. Adult patients requiring vv-ECMO for respiratory failure and undergoing unfractioned heparin (UFH) administration were enrolled and randomized whether to receive AT supplementation. Plasma samples for cytokine assay (IL-8, IL-10, IL-6, IL-1β, TNF-α and Pro-ADM) and heparinase TEG were collected from every patient before ECMO start, 24h and 72h after ECMO start, before ECMO removal, and 7days after ECMO removal or upon ICU discharge whichever happened first. AT concentration, coagulation and clinical data were collected before ECMO start and at pre-fixed time points. Thirty-nine patients were enrolled (21 treatments, 18 controls). TEG-R had a weak-to-moderate positive correlation with IL-8, IL-6, IL-10 and TNF-α and a moderate positive correlation with Pro-ADM. TEG-ANG showed a weak negative correlation with IL-8, IL-6 and TNF-α, while TEG-MA negatively correlated with IL-8, TNF-α and Pro-ADM. AT supplementation seemed to modify the association between TEG-MA and IL-8, IL-10 and Pro-ADM; conversely, AT did not affect the relationship among TEG-R or TEG-ANG and the studied cytokines. High concentrations of systemic cytokines correlated with longer reaction times and decreased angle and amplitude at TEG, suggesting that an increase in inflammation is related with hypocoagulability as revealed by thromboelastography.

Імунопатологічні аспекти етіопатогенезу міокардиту

Myocarditis is a group of inflammatory diseases of the heart muscle against the background of the absence of acute or chronic ischemic heart disease, which are diagnosed according to established histological, immunological and immunohistochemical criteria.Objective. Summarize current information on the immunopathogenesis of myocarditis based on data from open sources of information.Methods. Publications were selected based on PubMed, Clinical Key Elsevier, Cochrane Library, eBook Business Collection and Google Scholar databases, which covered information on the immunopathogenesis of myocarditis.Results. Viral infections are the most common cause of myocarditis, along with some bacteria and protozoa. Chronic immune stimulation or autoimmunity in chronic viral myocarditis results from incomplete resolution of the viral infection or response to a previous virus or immune-mediated chronic tissue injury. An active autoimmune response in human myocarditis, both at the cellular and humoral levels, is the immunological basis for the development of this pathology. Myocarditis caused by COVID-19 is a new entity. At the moment, four main manifestations of myocarditis in the context of SARS-CoV-2 have been identified: myocarditis associated with an acute infection of COVID-19, post-acute syndrome of COVID-19 (or prolonged syndrome of COVID-19), multisystem inflammatory syndrome, and myocarditis due to related to vaccination. Autoimmune reactions probably contribute to molecular mimicry – they activate virus-specific T-cells that attack the myocardium. During this phase, high concentrations of cytokines (eg, tumor necrosis factor, interleukins 1a, 1b, 2, and interferon-γ) are produced. These cytokines, together with antibodies against viral and cardiac proteins, further exacerbate cardiac damage and systolic dysfunction due to contractile dysfunction and matrix proteins.Conclusions. CD4+T-cells are defined as the main driving forces of heart-specific autoimmunity in myocarditis. Dysregulated CD4+ T-cell populations and their associated cytokines are critical for the development and progression of myocarditis and may serve as therapeutic targets and the development of new treatment approaches.

Insight into the Antioxidant Activity of Ascorbic Acid-Containing Gelatin Nanoparticles in Simulated Chronic Wound Conditions.

Chronic wounds differ from acute wounds by remaining in the inflammatory phase for a long time. This chronic inflammation confers a high concentration of inflammatory cytokines, proteases, and ROS. Likewise, the pH environment of chronic wounds has been recorded within the range of 7.2-8.9 due to the alkaline by-products of bacterial proliferation. In this work, differences in pH between healthy skin and chronic cutaneous wounds have been used for the design and development of pH-responsive gelatin-based nanoparticles (NPs). Ascorbic acid (AA), as an antioxidant compound that can neutralize reactive oxygen species (ROS), has been the therapeutic model compound included in these NPs. The goal of the present work has been the preparation and characterization (physicochemical and biological properties) of NPs for the effective release of AA under simulated chronic wound conditions. In vitro experiments demonstrated total AA release at pH corresponding to the chronic wounds. The biocompatible character of these gelatin-based NPs based on their hemolytic and cytotoxicity responses has been highlighted under in vitro conditions. The reversible and protective antioxidant properties of the AA-including NPs in erythrocytes and skin cell lines, respectively, have been confirmed to be modulated by the gelatin A gel strength.

Inflammation-mediated metabolic regulation in adipose tissue.

Chronic inflammation of adipose tissue is a prominent characteristic of many metabolic diseases. Lipid metabolism in adipose tissue is consistentlydysregulated during inflammation, which is characterized by substantial infiltration by proinflammatory cells and high cytokine concentrations. Adipose tissue inflammation is caused by a variety of endogenous factors, such as mitochondrial dysfunction, reactive oxygen species (ROS) production, endoplasmic reticulum (ER) stress, cellular senescence, ceramides biosynthesis and mediators of lipopolysaccharides (LPS) signaling. Additionally, the gut microbiota also plays a crucial role in regulating adipose tissue inflammation. Essentially, adipose tissue inflammation arises from an imbalance in adipocyte metabolism and the regulation of immune cells. Specific inflammatory signals, including nuclear factor-κB (NF-κB) signaling, inflammasome signaling and inflammation-mediated autophagy, have been shown to be involved in the metabolic regulation. The pathogenesis of metabolic diseases characterized by chronic inflammation (obesity, insulin resistance, atherosclerosis and nonalcoholic fatty liver disease [NAFLD]) and recent research regarding potential therapeutic targets for these conditions are also discussed in this review.

Do Intraoperative Platelet-Rich Plasma Injections Influence the Final Appearance of Vertical Scars after Breast Reduction? Spectrophotometric Analysis

Background: Platelet-rich plasma (PRP) has been shown to support wound healing and tissue regeneration due to its high concentration of growth factors and cytokines. This study aims to investigate the effect of intraoperative PRP injections on the final appearance of vertical scars after breast reduction, as well as to identify potential predictors of a scar’s aesthetic assessment using spectrophotometric parameters. Methods: In this prospective, randomized trial, 82 scars from 41 women who underwent bilateral breast reduction with an inverted T pattern were analyzed. PRP or a placebo substance (0.9% sodium chloride solution) was injected intraoperatively into the edges of vertical wounds. Spectrophotometric measurements of scar pigmentation were performed 3 and 6 months after surgery; additionally, two independent observers evaluated the aesthetic appearance of scars based on photographs. Results: The results showed that the use of intraoperative PRP injections did not significantly influence the final appearance of vertical scars after breast reduction. Conclusions: We indicated spectrophotometric variables (b) in the early stages of wound healing (after 3 months) that can be predictors of the final scar’s aesthetic outcome. This can be helpful in detecting scars that may need additional interventions to optimize the healing process.

Association of the key immunological and hemodynamic determinants with cervix ripening in pregnant women.

Aim: To investigate a correlation between cervical ripening, the immunological features and the hemodynamic characteristics of the cervix during the preparation for vaginal labor. Materials and Methods: We examined 75 pregnant women at different gestational age. General clinical and immunological studies were conducted in order to check serum concentration of cytokines IL-6, IL-1β, and TNF-α. Ultrasound and Doppler study were used to determine resistance index and systolic-diastolic ratio of blood flow in the common uterine artery as well as the descending and ascending parts and cervical stromal arteries. Results: Pregnant women with high cervical ripening score had high concentrations of the major proinflammatory cytokines (IL-1β, IL-6, and TNF-α). Analysis of the of the cervical blood flow indicators of the studied groups showed significant differences in the indices of vascular resistance in the vessels that feed the cervix. Our data showed a significant correlation between the cervix ripening and both the serum levels of the studied cytokines and the level of peripheral vascular resistance indices in the common uterine arteries of the cervix, and the blood flow indices in the cervical stromal vessels. Conclusions: Our study shows that the process of preparing the woman's body for labor is associated with immunological adjustment and increased hemodynamics of the cervix. We report that cervical ripening is associated with the immunological components and hemodynamic parameters of the cervix at late-stage pregnancy. Measuring cervix ripening and the accompanied changes in cytokine levels and hemodynamic parameters will form a more accurate assessment of birth preparedness and labor complications.

Role of TGF-β and p38 MAPK in TSG-6 Expression in Adipose Tissue-Derived Stem Cells In Vitro and In Vivo.

Mesenchymal stem cells (MSCs) regulate immune cell activity by expressing tumor necrosis factor-α (TNF-α)-stimulated gene 6 (TSG-6) in inflammatory environments; however, whether anti-inflammatory responses affect TSG-6 expression in MSCs is not well understood. Therefore, we investigated whether transforming growth factor-β (TGF-β) regulates TSG-6 expression in adipose tissue-derived stem cells (ASCs) and whether effective immunosuppression can be achieved using ASCs and TGF-β signaling inhibitor A83-01. TGF-β significantly decreased TSG-6 expression in ASCs, but A83-01 and the p38 inhibitor SB202190 significantly increased it. However, in septic C57BL/6 mice, A83-01 further reduced the survival rate of the lipopolysaccharide (LPS)-treated group and ASC transplantation did not improve the severity induced by LPS. ASC transplantation alleviated the severity of sepsis induced by LPS+A83-01. In co-culture of macrophages and ASCs, A83-01 decreased TSG-6 expression whereas A83-01 and SB202190 reduced Cox-2 and IDO-2 expression in ASCs. These results suggest that TSG-6 expression in ASCs can be regulated by high concentrations of pro-inflammatory cytokines in vitro and in vivo, and that A83-01 and SB202190 can reduce the expression of immunomodulators in ASCs. Therefore, our data suggest that co-treatment of ASCs with TGF-β or p38 inhibitors is not adequate to modulate inflammation.

3D printed strontium-doped calcium phosphate ceramic scaffold enhances early angiogenesis and promotes bone repair through the regulation of macrophage polarization

The vascularization of bone repair materials is one of the key issues that urgently need to be addressed in the process of bone repair. The changes in macrophage phenotype and function play an important role in the process of vascularization, and endowing bone repair materials with immune regulatory characteristics to enhance angiogenesis is undoubtedly a new strategy to improve the effectiveness of bone repair. In order to improve the effect of tricalcium phosphate (TCP) on vascularization and bone repair, we doped strontium ions (Sr) into TCP (SrTCP) and prepared porous 3D printed SrTCP scaffolds using 3D printing technology, and studied the scaffold mediated macrophage polarization and subsequent vascularization and bone regeneration. The results of the interaction between the scaffold and macrophages showed that the SrTCP scaffold can promote the polarization of macrophages from M1 to M2 and secrete high concentrations of VEGF and PDGF-bb cytokines, which shows excellent angiogenic potential. When human umbilical vein endothelial cells (HUVECs) were co-cultured with macrophage-conditioned medium of SrTCP scaffold, HUVECs exhibited excellent early angiogenesis-promoting effects in terms of scratch healing, angiogenic gene expression, and in vitro tube formation performance. The results of in vivo bone repair experiments showed that the SrTCP scaffold formed a vascular network with high density and quantity in the bone defect area, which could increase the rate of new bone formation and advance the period of bone formation, and finally achieved a better bone repair effect. We observed a cascade effect in which Sr-doped SrTCP scaffold regulate macrophage polarization to enhance angiogenesis and promote bone repair, which may provide a new strategy for the repair of clinical bone defects.

Neurological manifestations with jugular vein thrombosis linked to an inflammatory profile may be a sequela of long COVID

AbstractMore than 670 million cases of coronavirus disease 2019 (COVID‐19) have been recorded worldwide in the 3 years since the start of the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) pandemic. About 45% of survivors of COVID‐19 develop a syndrome known as long‐term COVID, in which symptoms persist even months after the acute infection. About 76% of patients with long COVID experience neurological manifestations. Moreover, patients who have survived COVID‐19 have an increased risk of cerebral venous thrombosis. This case report describes a 41‐year‐old woman who developed neurological manifestations associated with jugular vein thrombosis 24 h after administration of the Oxford–AstraZeneca (ChAdOx1 nCoV‐19) vaccine (AstraZeneca‐Serum Institute of India). She had been infected with SARS‐CoV‐2 three months before vaccination. Although initially suspected to be a case of vaccine‐induced immune thrombotic thrombocytopenia (VITT) in view of her recent vaccination, the patient did not have any hallmarks of VITT, such as thrombocytopenia, an increased d‐dimer level, or antibodies against platelet factor‐4. Moreover, the neurological manifestations were associated with a high concentration of inflammatory cytokines, including interleukin (IL)‐6, IL‐17A, and IL‐21, and elevated neutrophil levels in cerebrospinal fluid, suggesting that inflammatory immune components had a role in the development of thrombotic events and pointing to an alternative diagnosis. In this case, the laboratory results indicated that the neurological manifestations associated with jugular vein thrombosis were not associated with VITT. Therefore, we propose that the thrombosis of the left jugular vein was a sequela of SARS‐CoV‐2 infection.

LONG-TERM COVID-19 EFFECT TO ENDOTHELIAL DAMAGE TROUGH EXTRINSIC APOPTOSIS LED TO CARDIOVASCULAR DISEASE PROGRESSION: AN UPDATE REVIEW

COVID-19 can involve persistence, sequelae, and other medical complications that last weeks to months after initial recovery; these prolonged symptoms called as long-term covid-19 effect. Symptoms, signs, or abnormal clinical parameters persisting two or more weeks after COVID-19 onset that do not return to a healthy baseline can potentially be long-term effects of the disease. SARS-CoV-2 affects the cardiovascular system and causes conditions such as myocarditis, arrhythmias, and myocardial injury. Vascular damage from COVID-19 has been affected directly by the SARS-CoV-2 virus infection and indirectly by systemic inflammatory cytokine storm. This damage can be long-lasting and lead to various cardiovascular complications. Fas ligand (FasL)-Fas complex is a death factor that induces cell apoptosis. Fas and FasL have been detected in the endothelial wall, and it has been proposed that Fas-mediated apoptosis has a role in physiological and pathological cell turnover in the endothelial wall. High concentrations of inflammatory cytokines, such as cytokines storm induced by SARS-CoV-2 infection, are thought to increase the expression of FasL, which leads to an increase in the regulation of extrinsic apoptosis in endothelial cells leading to endothelial damage. This article summarises the current understanding of the long-term covid-19 effect on endothelial damage through extrinsic apoptosis Fas-FasL complex.

Determinants of serum cytokines in a population sample of healthy subjects from Iran

IntroductionCytokines are synthesized and released by immune system cells and mediate critical immune responses. Aging is associated with increased serum levels of some pro-inflammatory cytokines . A positive correlation between the concentration of several cytokines and blood pressure has been reported; higher cytokine concentrations may be related to the underlying causes of hypertension through the effects of inflammatory responses or as an independent etiology for hypertension .To assess the relationship between the serum levels of inflammatory cytokines and growth factors, with biochemical and anthropometric characteristics in healthy Iranian subjects.Material and methodsAnthropometric measurements and blood sampling were performed in 103 healthy Iranian participants. Fasting blood glucose (FBG), hs-CRP and lipid profile were measured in these participants. 12 serum cytokines/growth factors (MCP-1, TNF-α, EGF, IFN-γ, VEGF, IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-8 and IL-10 were measured.ResultsFBG was positively associated with serum IL-2, IL-4 and IL-1α (P = 0.044, &lt; 0.001 and = 0.017, respectively). Serum EGF and IL-4 were positively associated with age (P &lt; 0.001). IL-8 was inversely associated with SBP (P = 0.002) and gender (P = 0.028). There was a positive association between VEGF and HDL (P = 0.007). The serum levels of IFN-γ and TNF-α were positively associated with serum TG (P = 0.018 and 0.006, respectively).ConclusionsThere are associations between various pro-and anti-inflammatory cytokines in serum and several anthropometric measurements.

Immunological Reactivity and Intensity of Oxidative Stress in Stable Coronary Artery Disease

The aim. To analyze the relationship between immune response factors and the intensity of oxidation of lipoproteins and proteins in patients with stable coronary artery disease (CAD) to clarify the pathogenesis of coronary atherosclerosis.&#x0D; Materials and methods. A total of 179 patients with stable CAD of II-IV functional class, mean age 56 (49-62) years (main group) and 30 healthy individuals, mean age 49 (45-53) years (control group) were examined. The material for immunological research was peripheral venous blood. To determine the indicators of immunity, flow laser cytometry and enzyme-linked immunosorbent assay were used. Spectrophotometric and fluorometric methods were used to determine the levels of intermediate and final oxidation products of lipids and proteins, as well as antioxidant protection enzymes in the blood serum and in atherogenic lipoproteins.&#x0D; Results. A direct relationship between the activity of lipoprotein peroxidation and protein oxidation with a cell-type immune response and immune inflammation was revealed.&#x0D; Conclusions. The high intensity of lipid peroxidation and protein oxidation in patients with stable CAD (stable angina pectoris) is combined with significant activation of the T-cell component of the immune response (in terms of the ratio of helper and cytotoxic subpopulations of T-lymphocytes, high concentrations of pro-inflammatory cytokines, the state of the CD40/CD40L system, the level of expression of the CD95 apoptosis marker on cells), which indicates interdependence of T-cell immunity and oxidative stress in the pathogenesis of atherosclerosis. The dependence of the hyperproduction of pro-inflammatory cytokines by mononuclear blood cells on free radical oxidation of proteins, peroxidation of apoB proteins and the intensity of antiperoxide protection (catalase and superoxide dismutase enzymes) in patients with stable CAD indicates a contribution to the presence of oxidative stress and the development of immune inflammation. A comprehensive study of the factors of immunological reactivity, the violation of which can lead to the development of immunopathological reactions, and the intensity of oxidation of lipoproteins and proteins in patients with stable CAD helps to clarify the pathogenetic relationship between chronic immune inflammation, endothelial dysfunction and oxidative stress, and also substantiates the expediency of general therapeutic approaches to the treatment of CAD.

Evaluation of some immunological parameters for Staphylococcus xylosus infections in patients with Systemic lupus erythematosus

Purpose: Systemic lupus erythematosus (SLE) is a chronic, systemic autoimmune illness that manifests clinically as well as immunologically and in several lab tests abnormalities. Patients with SLE frequently get infections, which account for 30–50% of morbidity and death. The bacterial species Staphylococcus xylosus is a member of the Staphylococcus genus. This study's objective was to assess several immunological indicators of S.xylosus infections in individuals with systemic lupus erythematosus in the Najaf Governorate of Iraq. Subjects and Methods: Blood samples were taken from 60 SLE patients ranging in age from 16 to 56. Each patient has had a sample of 10 milliliters of blood taken. 5 ml were used to measure immunologic parameters, and another 5 ml were used to diagnose S. Xylosus by culturing a sample on blood agar and mannitol salt agar. culture on mannitol salt agar and blood agar. Results: According to the microbiological tests, 26 specimens (or 43.3%) had isolated bacteria, whereas 34 specimens (or 56.7%) had no sign of bacterial growth. Out of the 26 blood samples collected, S.xylosus was detected in 2 samples. normal amounts of ANA and anti ds-DNA despite SLE sufferers. The results of this study showed that serum levels of CD69, IL-21, and IL-35 significantly increased when compared with controls, despite a substantial drop in Hb, WBC, and platelet counts but an elevated ESR. Conclusions: xylosus produces normal autoantibody levels that are utilized to diagnose SLE. An important factor in the pathophysiology of SLE, which causes the disease to develop, is a high concentration of inflammatory cytokines.

Hippo pathway-manipulating neutrophil-mimic hybrid nanoparticles for cardiac ischemic injury via modulation of local immunity and cardiac regeneration

The promise of regeneration therapy for restoration of damaged myocardium after cardiac ischemic injury relies on targeted delivery of proliferative molecules into cardiomyocytes whose healing benefits are still limited owing to severe immune microenvironment due to local high concentration of proinflammatory cytokines. Optimal therapeutic strategies are therefore in urgent need to both modulate local immunity and deliver proliferative molecules. Here, we addressed this unmet need by developing neutrophil-mimic nanoparticles NM@miR, fabricated by coating hybrid neutrophil membranes with artificial lipids onto mesoporous silica nanoparticles (MSNs) loaded with microRNA-10b. The hybrid membrane could endow nanoparticles with strong capacity to migrate into inflammatory sites and neutralize proinflammatory cytokines and increase the delivery efficiency of microRNA-10b into adult mammalian cardiomyocytes (CMs) by fusing with cell membranes and leading to the release of MSNs-miR into cytosol. Upon NM@miR administration, this nanoparticle could home to the injured myocardium, restore the local immunity, and efficiently deliver microRNA-10b to cardiomyocytes, which could reduce the activation of Hippo-YAP pathway mediated by excessive cytokines and exert the best proliferative effect of miR-10b. This combination therapy could finally improve cardiac function and mitigate ventricular remodeling. Consequently, this work offers a combination strategy of immunity modulation and proliferative molecule delivery to boost cardiac regeneration after injury.

Abstract A005: Regulation of HHLA2 expression in renal cell carcinoma and myeloid cells

Abstract The immune checkpoint HERV-H LTR-associating 2 (HHLA2) is expressed in many tumors, including clear cell renal cell carcinoma (ccRCC). Multiple therapeutics directed against HHLA2 or its inhibitory receptor KIR3DL3 are about to enter clinical trials in metastatic RCC; however, little is known about the regulation of HHLA2 expression. Better understanding the regulation of HHLA2 in tumor cells and within the tumor microenvironment will facilitate translation of these therapeutic agents into the clinic by assisting in patient selection and development of rational drug combinations. Using flow cytometry, immunohistochemistry (IHC), and RNA analysis, HHLA2 expression was examined in monocytes, primary nephrectomy specimens and the established ccRCC cell lines, A498 and 786-0. A panel of cytokines was screened for the induction of HHLA2 in vitro. In vivo expression of HHLA2 in A498 and 786-0 human kidney cancer xenograft mouse models was examined. Tumor cells obtained from these xenograft models (either freshly isolated or cultured ex vivo) were characterized by RNASeq and flow cytometry. Analysis of HHLA2 expression in monocytes shows that among a wide range of cytokines tested, only IL-10 and BMP4, and to a lesser extent, IL-1b and IL-6, modestly enhanced HHLA2 mRNA and protein expression. These combinations of cytokines failed to induce HHLA2 in both A498 and 786-0. HHLA2 was frequently expressed in primary ccRCC tumors by IHC. Interestingly, analysis of HHLA2 by flow cytometry in primary RCC tumors showed that HHLA2 is progressively lost over 4 weeks when cells are cultured ex vivo. Hypoxia alone did not change HHLA2 expression. While HHLA2 was not expressed on either A498 or 786O cells in vitro, both A498 and 786-0 cells expressed HHLA2 when grown as subcutaneous xenografts in NSG immunodeficient mice. A498 xenografts express significantly more HHLA2 than 786-0 xenografts. HHLA2 expression is differentially regulated in monocytes and kidney cancer epithelial cells. High concentrations of cytokines, particularly IL10, that induce HHLA2 expression in monocytes fail to upregulate HHLA2 expression in ccRCC; however, the tumor microenvironment in NSG mice significantly induced HHLA2 expression in both A498 and 786-0 xenografts. Complementary whole genome CRISPR knock out and gain-of-function screens are underway to assess by an unbiased means both nonimmune and immunologic regulators or repressors that may be responsible for inducing HHLA2 in kidney cancer in vivo. Furthermore, the A498 xenograft mouse model is an excellent humanized HHLA2 model for testing regulation of HHLA2 and HHLA2-directed therapeutics. Citation Format: Tomonari Shigemura, Nahuel Perrot, Zimo Huang, Aseman Bagheri Sheshdeh, Nourhan El Ahmar, David McDermott, Sabina Signoretti, Gordon Freeman, Kathleen Mahoney. Regulation of HHLA2 expression in renal cell carcinoma and myeloid cells [abstract]. In: Proceedings of the AACR Special Conference: Advances in Kidney Cancer Research; 2023 Jun 24-27; Austin, Texas. Philadelphia (PA): AACR; Cancer Res 2023;83(16 Suppl):Abstract nr A005.

#4983 THE UNEXPECTABLE BALANCE OF PROINFLAMMATORY CELLS IN PERITONEAL DIALYSIS PATIENTS

Abstract Background and Aims Chronic kidney disease (CKD) is a complex and heterogeneous disease and is increasingly becoming a global public health concern. It is is characterized by a persistent inflammation state which appear to be caused by cytokines, grown factors and hormones. Peritoneal dialysis (PD) accounts for 9% of all kidney replacement therapy (KRT) and over time, some changes are expected to occur in the peritoneal membrane mainly due to exposure to PD solutions, infectious processes and non-infectious complications. This inflammatory process is poorly understood and needs further clarification, but Th17 cells and Th1 cells seem to be involved. Therefore, we aimed to quantify the frequency of peripheral immune cells and the concentration of IL-17A in peripheral blood (PB) and peritoneal effluent (PE) and compare to a healthy control group. Method In a cross-sectional study of 26 PD patients and 10 healthy, age and sex-matched controls we evaluated PB and PE frequencies of T lymphocytes, T CD4, T CD8 and Th1 cells by flow cytometry as well as IL-17 concentrations using enzyme-linked immunosorbent assay. Comparisons were performed between PD patients and controls and between the different groups of PD patients according to PD modality, number of exchanges, dialysate tonicity, extraneal use, infusion and daily total volumes, type of peritoneal transport and volume indexes. Statistical analyses were performed using the SPSS statistics version 26. Results Table 1 summarizes the main characteristics of PD patients and controls. Overall, in comparison with the control group, the frequency of Th1 cells in PB of PD patients was significantly lower (P = 0.001). On the other hand, frequency of Th1 cells substantially expanded in the PE, as compared to the PB (P = 0.001). PD patients also presented lower Th17 cells frequencies (P = 0.061) and those prescribed Extraneal had the lowest frequencies of Th17 (P = 0.030). IL-17A concentration was significantly higher in PE vs PB of PD patients (P = 0.012). Finally, the frequency of total lymphocytes in high PD transporters was significantly higher in comparison with high-average transporters (P = 0.021). Conclusion In our cohort, PE presented high concentrations of proinflammatory cells and cytokines. Th1 cells rather than Th17 cells were increased, pointing to a predominant cytolytic activity but IL-17 was also increased. Treatment with Extraneal associated with a lower frequency of these cells, somehow counterbalancing the inflammatory millieu associated with high glucose concentrations.

Prospects of Platelet-Rich Plasma in Regenerative Medicine

Platelet-rich plasma (PRP) is a promising tool in regenerative medicine because it stimulates tissue repair and regeneration. PRP contains a high concentration of platelets, growth factors, and cytokines involved in the healing process. This editorial paper aims to give an overview of PRP in regenerative medicine and its potential applications in various medical fields such as orthopedics, dentistry, dermatology, and wound healing. PRP can be integrated with other regenerative therapies, such as stem cell and gene therapy, to enhance tissue repair and regeneration. Therefore, PRP holds great promise as a regenerative medicine tool, and further research is needed to optimize its use and develop standardized protocols for its preparation and application.

Pore size-mediated macrophage M1 to M2 transition affects osseointegration of 3D-printed PEEK scaffolds.

Increasing evidence indicates that macrophages play an important role in angiogenesis and bone regeneration. Because the phenotypic polarization of macrophage is extremely sensitive to the pore size of materials, poly(ether-ether-ketone) (PEEK) scaffolds with pore sizes of 0, 200, and 400 μm were prepared, and the influence of pore size-mediated macrophage polarization on subsequent angiogenesis and osteogenesis was examined. The interaction results of macrophages and scaffolds indicated that macrophages were responsive to the pore size of three-dimensional (3D)-printed PEEK scaffolds, and large pore size scaffolds showed greater potential in inducing M1 to M2 transition of macrophage and enhanced macrophage secretion of high concentrations of osteogenesis-related and angiogenesis-related cytokines. When human umbilical vein endothelial cells (HUVECs) and bone marrow mesenchymal stem cells (BMSCs) were cultured in the conditioned medium derived from co-culture of macrophages and scaffolds, HUVECs showed good angiogenic responses in terms of cell migration and angiogenic gene expression, while BMSCs showed good osteogenic differentiation effect in in vitro mineralization and osteogenesis-related gene expression. The results of bone defect repair showed that the bone volume/total volume ratio and trabecular thickness of the large pore size PEEK scaffold were significantly higher, and it had better biomechanical properties and achieved a better osseointegration effect. Our data demonstrate that large-pore PEEK scaffolds promote angiogenesis and osteogenic differentiation in vitro and osseointegration in vivo, most likely because scaffolds with larger pore size are able to mediate a higher degree of M1 to M2 transition in macrophages.

A cytokine-induced spheroid-based in vitro model for studying osteoarthritis pathogenesis.

Given the lack of in vitro models faithfully reproducing the osteoarthritis (OA) disease on-set, this work aimed at manufacturing a reliable and predictive in vitro cytokine-based Articular Cartilage (AC) model to study OA progression. Cell spheroids of primary human fetal chondrocytes (FCs) and h-TERT mesenchymal stem cells differentiated chondrocytes (Y201-C) were analysed in terms of growth kinetics, cells proliferation and apoptosis over 10 days of culture, in healthy condition or in presence of cytokines (interleukin-1ß, -6 and TNF-α). Then, the spheroids were assembled into chondrospheres using a bottom-up strategy, to obtain an in vitro cytokines-induced OA model. The resulting chondrospheres were evaluated for gene expression and anabolic ECM proteins. Compared to the healthy environment, the simulated OA environment induced chondrocyte hyperproliferation and apoptotic pathway, decreased expression of anabolic ECM proteins, and diminished biosynthetic activity, resembling features of early-stage OA. These characteristics were observed for both Y201-C and HC at high and low concentrations of cytokines. Both HC and Y201-C demonstrated the suitability for the manufacturing of a scaffold-free in vitro OA model to facilitate studies into OA pathogenesis and therapeutic strategies. Our approach provides a faithful reproduction of early-stage osteoarthritis, demonstrating the ability of obtaining different disease severity by tuning the concentration of OA-related cytokines. Given the advantages in easy access and more reproducible performance, Y201-C may represent a more favourable source of chondrocytes for establishing more standardized protocols to obtain OA models.