CXC Ligand Research Articles

WAY-100635 Alleviates Corneal Lesions Through 5-HT1A Receptor-ROS-Autophagy Axis in Dry Eye.

Purpose: To explore whether 5-HT1A receptors are involved in the dry eye disease (DED) mouse model and reveal its underlying mechanism.Methods: A C57BL/6J mouse DED model was established via the administration of 0.2% benzalkonium chloride twice a day for 14 days. Corneal fluorescein sodium staining score and Schirmer I test were checked before, and on days 7, 14, and 21 after treatment. The experiment was randomly divided into control, DED, 5-HT1A receptor agonist with or without N-acetylcysteine (NAC) and 5-HT1A receptor antagonist with or without NAC groups. The mRNA expression of inflammatory cytokines was measured by reverse transcription-quantitative polymerase chain reaction. Cellular reactive oxygen species (ROS) were detected by 2', 7'-dichlorodihydrofluorescein diacetate assays. Western blot analysis was used to measure the expression levels of autophagic proteins microtubule-associated protein 1 light chain 3 (LC3B-I/II) and autophagy-related gene 5 (ATG5).Results: 5-HT1A receptor agonist (8-OH-DPAT) increased corneal fluorescein sodium staining spots and 5-HT1A receptor antagonist (WAY-100635) decreased them. Treatment with 8-OH-DPAT was associated with the gene expression of more inflammatory cytokines, such as interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), C-C motif chemokine ligand 2 (CCL2) and C-X-C motif chemokine ligand 10 (CXCL10) compared with treatment with WAY-100635. An increased expression of LC3B-I/II and ATG5 was observed in corneal epithelial cells in the mouse model of DED. 8-OH-DPAT significantly enhanced the expression of LC3B-I/II and ATG5 by disrupting ROS levels. WAY-100635 alleviates autophagy by inhibiting ROS production.Conclusion: Excessive ROS release through 8-OH-DPAT induction can lead to impaired autophagy and increased inflammatory response in DED. WAY-100635 reduces corneal epithelial defects and inflammation in DED, as well as alleviates autophagy by inhibiting ROS production. The activation of the 5-HT1A receptor-ROS-autophagy axis is critically involved in DED development.

Tocotrienol-rich Fraction Modulated Genes Responsible for Inflammation in Lipopolysaccharide-stimulated RAW 264.7 Macrophages

Background: Inflammation plays a vital role in the pathogenesis of chronic non-communicable diseases (NCDs), the leading health issue worldwide. An earlier study reported that tocotrienol-rich fraction (TRF) showed better anti-inflammation effects in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages.
 Aim: This study aimed to investigate the anti-inflammatory effects of tocotrienol-rich fraction at the molecular level by looking at the genes that were differentially regulated and pathways affected in LPS-stimulated macrophages exposed to TRF using the microarray approach.
 Methods: A microarray study was carried out in LPS-stimulated RAW 264.7 macrophages. Total ribonucleic acid (RNA) was extracted from the RAW 264.7 cells treated with TRF (10µg/mL), alpha-tocopherol (10 µg/mL) or LPS (10 ng/mL). Untreated cells served as control. Enrichment analyses, such as Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG), were conducted for genes listed in the differentially expressed genes (DEGs). 
 Results: The microarray analysis showed that the expression of five genes [Hamp, Interleukin-1a (IL-1a), IL-b, C-X-C motif chemokine ligand 2 (CXCL2) and colony-stimulating factor 3 (CSF3)] and one gene (SLC1A4), an amino acid transporter, was modulated (fold change 2, P< 0.05) in the TRF-treated cells. With a more stringent analysis (fold change 3, P < 0.05), only one gene (CSF3) was downregulated in the TRF-treated in RAW 264.7 cells. Analysis using the GO and KEGG pathways revealed interactions between pro-inflammatory agents such as tumor necrosis factor-alpha (TNFα) and nuclear factor kappa-light-chain-enhancer of activated B-cells (NF-B), as well as signaling pathways of interleukin (IL)-1 and IL-17.
 Conclusion: TRF modulated the expression of genes responsible for acute and chronic inflammation that were part of the lipoxygenase (LOX) and cyclooxygenase (COX) inflammatory pathways. Further investigation on the effects of TRF in different cell lines and in vivo studies should be conducted in the future.

Identification of genes associated with susceptibility to persistent breeding-induced endometritis by RNA-sequencing of uterine cytobrush samples

This study aimed to investigate the susceptibility to persistent breeding-induced endometritis (PBIE). Cytobrush samples were collected from 81 broodmares 1–3 days before artificial insemination (AI). Susceptibility to PBIE was evaluated by the presence of ≥ 2 cm of intrauterine fluid 24 h after AI, besides the fertility was determined by a sonographic pregnancy diagnosis 2 weeks after ovulation. RNA expressions were compared between susceptible non-pregnant (SNP) mares (n=9) and resistant pregnant (RP) mares (n=9) as well as between susceptible pregnant (SP) mares (n=9) and susceptible non-pregnant (SNP) mares. 66 differentially expressed genes (DEGs) were identified between SNP and RP mares and 60 DEGs between SP and SNP mares. In SNP compared to RP mares, transcript levels of genes regulating steroid hormone metabolism and neutrophil chemotaxis were lower, while higher for genes participating in uterine inflammation.Transcripts of genes related to extracellular matrix degradation, tissue adhesions, and fibrosis were lower in SP mares than in SNP mares, while higher for genes related to uterine cell proliferation, differentiation, and angiogenesis in SP mares than SNP mares. In conclusion, increased transcript levels of apolipoprotein E (APOE) and roundabout 2 (ROBO2), cluster domain 44 (CD44), integrin beta 3 (ITGB3), and epidermal growth factor (EGF) are possible biomarkers for susceptibility to PBIE. While higher expression of fibroblast growth factor 9 (FGF9), kinase domain receptor (KDR), and C-X-C motif chemokine ligand (CXCL) 16, collagen type V alpha 2 (COL5A2) and fibronectin (FN1) are suggested indicators of fertility in susceptible mares if they receive proper breeding management.

CXCL16/CXCR6 Axis in Adipocytes Differentiated from Human Adipose Derived Mesenchymal Stem Cells Regulates Macrophage Polarization.

Adipocytes interact with adipose tissue macrophages (ATMs) that exist as a form of M2 macrophage in healthy adipose tissue and are polarized into M1 macrophages upon cellular stress. ATMs regulate adipose tissue inflammation by secreting cytokines, adipokines, and chemokines. CXC-motif receptor 6 (CXCR6) is the chemokine receptor and interactions with its specific ligand CXC-motif chemokine ligand 16 (CXCL16) modulate the migratory capacities of human adipose-derived mesenchymal stem cells (hADMSCs). CXCR6 is highly expressed on differentiated adipocytes that are non-migratory cells. To evaluate the underlying mechanisms of CXCR6 in adipocytes, THP-1 human monocytes that can be polarized into M1 or M2 macrophages were co-cultured with adipocytes. As results, expression levels of the M1 polarization-inducing factor were decreased, while those of the M2 polarization-inducing factor were significantly increased in differentiated adipocytes in a co-cultured environment with additional CXCL16 treatment. After CXCL16 treatment, the anti-inflammatory factors, including p38 MAPK ad ERK1/2, were upregulated, while the pro-inflammatory pathway mediated by Akt and NF-κB was downregulated in adipocytes in a co-cultured environment. These results revealed that the CXCL16/CXCR6 axis in adipocytes regulates M1 or M2 polarization and displays an immunosuppressive effect by modulating pro-inflammatory or anti-inflammatory pathways. Our results may provide an insight into a potential target as a regulator of the immune response via the CXCL16/CXCR6 axis in adipocytes.

Chemokine level predicts the therapeutic effect of anti-PD-1 antibody (nivolumab) therapy for malignant melanoma.

Anti-programmed cell death protein 1 (PD-1) antibody drugs, nivolumab and pembrolizumab, are regarded as first-line therapies for advanced malignant melanoma. Anti-PD-1 therapy suppresses tumor immunity, and the therapeutic effect is frequently correlated with the number of tumor-infiltrating lymphocytes (TIL) and tumor mutation burden (TMB). However, sampling tumor tissues from the metastatic sites to examine the number of TILs and TMB level is often challenging. Herein, we focused on chemokines in blood to determine whether they can predict the therapeutic effect of anti-PD-1 (nivolumab) therapy. First, we measured 44 types of chemokines and cytokines in the blood of 8 advanced malignant melanomas before anti-PD-1 (nivolumab) treatment and examined the relationship between the levels of these proteins and therapeutic effect of the drug treatment, which suggested that C-C motif chemokine 5 (CCL5) and C-X-C motif chemokine ligand 12 (CXCL12) were candidates for biomarkers to predict the therapeutic effect of anti-PD-1 therapy. Next, we measured the blood levels of CCL5 and CXCL12 in 22 patients with advanced malignant melanomas before the administration of anti-PD-1 antibody. We evaluated tumor infiltration of CD8-positive T cells by immunostaining in nine patients in whom the metastatic site could be sampled at the beginning of the treatment. The patients with lower than average levels of CCL5 and CXCL12 had a large number of TILs (P = 0.04) and good disease-specific survival rate (P = 0.04). Therefore, CCL5 and CXCL12 could likely be used as biomarkers to predict the therapeutic effect of anti-PD-1 (nivolumab) therapy.

Change of gene expression profiles in human cardiomyocytes and macrophages infected with SARS-CoV-2 and its significance.

Coronavirus disease 2019 (COVID-19) is an acute respiratory infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 can damage the myocardium directly, or activate the immune system, trigger a cytokine storm, and cause inflammatory cells to infiltrate the myocardial tissue and damage the myocardium. This study is based on the sequencing data to analyze the changes in gene expression of cardiomyocytes and macrophages after SARS-CoV-2 infection, and explore the potential effects of SARS-CoV-2 on the heart and immune system. The public data set GSE151879 was retrieved. The online software Network Analyst was used to preprocess the data, and the differentially expressed genes (DEGs) [log2(fold change)>2, adjusted P-value<0.05] screening between the infection group and the control group in cardiomyocytes, human embryonic stem cell-derived cardiomyocytes, and macrophages were screened. Consistent common differentially expressed genes (CCDEGs) with the same expression pattern in cardiomyocytes and macrophages were obtained, and the online analysis software String was used to conduct enrichment analysis of their biological functions and signal pathways. Protein-protein interaction network, transcription factor-gene interaction network, miRNA-gene interaction network and environmental chemical-gene interaction network were established, and Cytoscape 3.72 was used to perform visualization. After data standardization, the data quality was excellent and it can ensure reliable results. Myocardial cell infection with SARS-CoV-2 and gene expression spectrum were changed significantly, including a total of 484 DEGs in adult cardiomyoblasts, a total of 667 DEGs in macrophages, and a total of 1 483 DEGs in human embryo source of cardiomyopathy. The Stum, mechanosensory transduction mediator homolog (STUM), dehydrogenase/reductase 9 (DHRS9), calcium/calmodulin dependent protein kinase II beta (CAMK2B), claudin 1(CLDN1), C-C motif chemokine ligand 2 (CCL2), TNFAIP3 interacting protein 3 (TNIP3), G protein-coupled receptor 84 (GPR84), and C-X-C motif chemokine ligand 1 (CXCL1) were identical in expression patterns in 3 types of cells. The protein-protein interaction suggested that CAMK2B proteins may play a key role in the antiviral process in 3 types of cells; and silicon dioxide (SiO2), benzodiazepine (BaP), nickel (Ni), and estradiol (E2) affect anti-SARS-CoV-2 processes of the 3 types of cells. CAMK2B, CLDN1, CCL2, and DHRS9 genes play important roles in the immune response of cardiomyocytes against SARS-CoV-2. SiO2, BaP, Ni, E2 may affect the cell's antiviral process by increasing the toxicity of cardiomyocytes, thereby aggravating SARS-CoV-2 harm to the heart.

C-X-C Motif Chemokine Ligand 9 and Its CXCR3 Receptor Are the Salt and Pepper for T Cells Trafficking in a Mouse Model of Gaucher Disease.

Gaucher disease is a lysosomal storage disease, which happens due to mutations in GBA1/Gba1 that encodes the enzyme termed as lysosomal acid β-glucosidase. The major function of this enzyme is to catalyze glucosylceramide (GC) into glucose and ceramide. The deficiency of this enzyme and resultant abnormal accumulation of GC cause altered function of several of the innate and adaptive immune cells. For example, augmented infiltration of T cells contributes to the increased production of pro-inflammatory cytokines, (e.g., IFNγ, TNFα, IL6, IL12p40, IL12p70, IL23, and IL17A/F). This leads to tissue damage in a genetic mouse model (Gba19V/−) of Gaucher disease. The cellular mechanism(s) by which increased tissue infiltration of T cells occurs in this disease is not fully understood. Here, we delineate role of the CXCR3 receptor and its exogenous C-X-C motif chemokine ligand 9 (CXCL9) in induction of increased tissue recruitment of CD4+ T and CD8+ T cells in Gaucher disease. Intracellular FACS staining of macrophages (Mϕs) and dendritic cells (DCs) from Gba19V/− mice showed elevated production of CXCL9. Purified CD4+ T cells and the CD8+ T cells from Gba19V/− mice showed increased expression of CXCR3. Ex vivo and in vivo chemotaxis experiments showed CXCL9 involvement in the recruitment of Gba19V/− T cells. Furthermore, antibody blockade of the CXCL9 receptor (CXCR3) on T cells caused marked reduction in CXCL9- mediated chemotaxis of T cells in Gba19V/− mice. These data implicate abnormalities of the CXCL9-CXCR3 axis leading to enhanced tissue recruitment of T cells in Gaucher disease. Such results provide a rationale for blockade of the CXCL9/CXCR3 axis as potential new therapeutic targets for the treatment of inflammation in Gaucher disease.

Altered plasma cytokines in dogs with atopic dermatitis.

BackgroundCanine (Canis lupus familiaris) atopic dermatitis (AD) shares similar clinical signs to human AD. The abnormal immune response of AD is orchestrated by T lymphocytes, and may include variable involvement of cytokines, regulatory T (Treg) cells, eosinophils, mast cells and other immune components. Helper T (Th)2 cytokines often predominate initially, followed by Th1 cytokines in more chronic phases.Hypothesis/ObjectivesPro‐inflammatory and Treg cytokines have been shown to play a role in human AD, yet their importance is not clear in canine AD. Hence, this study aimed to measure the concentrations of cytokines/chemokines not traditionally associated with Th1/Th2 response.AnimalsCanine AD patients (n = 27), compared to control dogs (n = 11).Methods and materialsA total of 19 plasma cytokines were assayed using canine specific multiplex immuno‐assays.ResultsThe plasma concentrations of CXC Motif Chemokine Ligand 8 (CXCL8), interleukin (IL)‐7 and IL‐15 cytokines were elevated in canine AD patients, compared to control dogs. In addition, stem‐cell factor (SCF) concentrations were reduced in the plasma of canine AD patients compared to control dogs. Distinct cytokine profiles were found in dogs belonging to the Staffordshire breeds, a group with increased risk of AD. In particular, granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) had significantly elevated concentrations.Conclusions and clinical relevanceSome of the plasma cytokine alterations in canine AD described here, particularly of IL‐7, have not been reported previously. Monitoring these distinctive cytokine alterations could be useful for diagnosis and monitoring of canine AD in dogs.

Apremilast effectively inhibits TNFα-induced vascular inflammation in human endothelial cells.

Patients with chronic inflammatory diseases (e.g. psoriasis and rheumatoid arthritis) are at increased risk for the development of atherosclerosis and cardiovascular diseases (CVD). Previous studies have suggested that phosphodiesterase 4 (PDE4) inhibitors possess anti-inflammatory properties. Here we examined the effect of the PDE4 inhibitor apremilast, a well-established anti-psoriatic drug, on pro-inflammatory responses in TNFα-activated endothelial cells. Human umbilical vein endothelial cells (HUVEC) were treated with tumour necrosis factor-α (TNFα) in the presence or absence of apremilast. Expression levels of pro-inflammatory cytokines, chemokines and adhesion molecules were assessed by ELISA, western blot and RT-PCR. Effects of apremilast on adhesion and transendothelial migration (TEM) of THP-1 monocytic cells were analysed in transwell assays. Apremilast suppressed TNFα-induced expression and secretion of important endothelial and monocytic pro-inflammatory factors, including granulocyte-macrophage colony-stimulating factor (GM-CSF), C-X-C motif chemokine ligand 10 (CXCL10), chemokine (C-C motif) ligand 2 (CCL2), vascular cell adhesion molecule 1 (VCAM-1), E-selectin and matrix metalloproteinase-9 (MMP9). Functionally, apremilast reduced adhesion of THP-1 cells to activated HUVECs and TEM in response to TNFα. Mechanistically, apremilast suppressed activation of nuclear factor κB (NFκB) and mitogen-activated protein kinases (MAPK) signalling in activated HUVECs. Furthermore, inhibition of p38, C-Jun-N-terminale Kinase (JNK) and NFκB in activated HUVECs decreased expression of GM-CSF, VCAM-1 and E-selectin. Additionally, apremilast decreased IL-17A-induced secretion of IL-6 and CCL2. We demonstrate that apremilast has distinct anti-inflammatory effects in activated HUVECs, indicating that apremilast could have the therapeutic potential to prevent higher risk for CVD in patients with chronic inflammatory diseases.

C-X-C motif chemokine ligand 1 and its receptor C-X-C motif chemokine receptor 2 in trigeminal ganglion contribute to nerve injury-induced orofacial mechanical allodynia.

Orofacial ectopic pain induced by trigeminal nerve injury is a serious complication of dental treatment. C-X-C motif chemokine ligand 1 (CXCL1) and its primary receptor C-X-C motif chemokine receptor 2 (CXCR2) contribute to the development and maintenance of neuropathic pain in the spinal nervous system, but their roles in trigeminal neuropathic sensation are still poorly understood. This study aimed to investigate the exact role of CXCL1 and CXCR2 in the regulation of orofacial ectopic mechanical allodynia and their potential downstream mechanisms in the trigeminal ganglion (TG). The head withdrawal threshold (HWT) of C57BL/6mice was evaluated after inferior alveolar nerve (IAN) transection (IANX). Then, the distribution and expression of CXCL1 and CXCR2, and their potential downstream mechanisms in the TG were further measured using immunohistochemistry, real-time reverse transcription-quantitative polymerase chain reaction and Western blotting. Moreover, the effect of SB225002 (an inhibitor of CXCR2) on mechanical allodynia was examined. The data were analysed using the Student's t test and a analysis of variance (ANOVA). IANX triggered persistent (>21days) mechanical allodynia and upregulation of CXCL1 and CXCR2 in the TG. In addition, exogenous CXCL1 also lowered the HWT, which was alleviated by CXCR2 and protein kinase C (PKC) antagonists (p<.05). In addition, IANX increased the phosphorylated PKC (p-PKC) levels and decreased the expression of voltage-gated potassium channels (Kv), and these effects were reversed by inhibition of CXCR2 (p<.05). Our results demonstrated that CXCR2 participated in orofacial ectopic mechanical allodynia via downregulation of Kv1.4 and Kv1.1 through the PKC signalling pathway. This mechanism may be a potential target in developing a treatment strategy for ectopic orofacial pain.

Transcriptome Profile During Rabies Virus Infection: Identification of Human CXCL16 as a Potential New Viral Target.

Rabies virus (RABV), the causative agent for rabies disease is still presenting a major public health concern causing approximately 60,000 deaths annually. This neurotropic virus (genus Lyssavirus, family Rhabdoviridae) induces an acute and almost always fatal form of encephalomyelitis in humans. Despite the lethal consequences associated with clinical symptoms of rabies, RABV limits neuro-inflammation without causing major histopathological lesions in humans. Nevertheless, information about the mechanisms of infection and cellular response in the central nervous system (CNS) remain scarce. Here, we investigated the expression of inflammatory genes involved in immune response to RABV (dog-adapted strain Tha) in mice, the most common animal model used to study rabies. To better elucidate the pathophysiological mechanisms during natural RABV infection, we compared the inflammatory transcriptome profile observed at the late stage of infection in the mouse brain (cortex and brain stem/cerebellum) with the ortholog gene expression in post-mortem brain biopsies of rabid patients. Our data indicate that the inflammatory response associated with rabies is more pronounced in the murine brain compared to the human brain. In contrast to murine transcription profiles, we identified CXC motif chemokine ligand 16 (CXCL16) as the only significant differentially expressed gene in post-mortem brains of rabid patients. This result was confirmed in vitro, in which Tha suppressed interferon alpha (IFN-α)-induced CXCL16 expression in human CNS cell lines but induced CXCL16 expression in IFN-α-stimulated murine astrocytes. We hypothesize that RABV-induced modulation of the CXCL16 pathway in the brain possibly affects neurotransmission, natural killer (NK) and T cell recruitment and activation. Overall, we show species-specific differences in the inflammatory response of the brain, highlighted the importance of understanding the potential limitations of extrapolating data from animal models to humans.

Clinical and Immunological Assessment of Patients with Sars-Cov-2 Infections

▪Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induced coronavirus disease-2019 (COVID-19) has presented humanity with unprecedented challenges. Severe disease is associated with acute respiratory distress syndrome (ARDS), use of mechanical ventilation, ICU stay and prolonged hospitalization, The role of the immune system in the pathogenesis of COVID-19 disease is still unclear, which imposes limitations on identifying potential immunotherapy that can improve care for acute and chronic phases of COVID-19 in conjunction with current therapies. Research efforts are ongoing for more than 1 year to identify key immunological mechanisms involved in the disease process. While insightful, this knowledge is still incomplete and can be complemented with the assessment of immune response kinetics. Such assessment will help with the identification of early interventional modalities of immune cell regulation. With these considerations in mind, we aimed to assess several parameters of immune system regulation during the current medical care of patients with COVID-19.Methods: This is a pre-clinical prospective cohort study which involved laboratory-based assessments of blood samples obtained from COVID-19 patients and healthy volunteers. The study population was divided into three cohorts. Our first cohort included 18 years and older COVID-19 patients with respiratory complaints, oxygen (O2) saturations of less than or equal to 92 and pulmonary infiltrates on an imaging study or who were critically ill and required ventilatory support. Second cohort included 18 years and older COVID-19 patients who were hospitalized and did not require ventilatory support. Third cohort included participants with no prior diagnosis of COVID-19, or any recent viral respiratory symptoms including fever, cough or shortness of breath for the last 2 weeks. Patients with an established diagnosis of cancer or immunologic disorders were excluded. Blood specimens were collected over the period of hospitalization: specimen number 1 on day 1-3 of hospitalization, specimen number 2 on days 3-4 of hospitalization, specimen number 3 on days 5-7 of hospitalization, and specimen number 4 on 7-30 days after discharge. We performed capillary electrophoresis for serology and automated ELISA for cytokine measurement. We collected clinical data on patient demographic, clinical characteristics such as presence of any acute and chronic comorbidities and serum inflammatory markers C-Reactive Protein, D-Dimer and Ferritin.Results: We had 15 patients in cohort 1, 10 in cohort 2 and 15 in cohort 3. Patients in cohort 1 were older and had higher comorbidities. Males constituted a substantially high percentage of patients in cohort 1 and 2 (60% and 70% respectively). Patients had similar BMI in cohort 1 and 2. Total antibody levels were highest in cohort 1 but an upward trend over the course of hospitalization was noted in all cohorts. Most interesting pattern was noted in the context of antibodies against spike protein S1 receptor-binding domain (S1RBD) where patients in cohort 2 developed minimal S1RBD antibodies. Cohort 1 on average had higher levels of Interleukin 6(IL-6), Interleukin 8(IL-8), C-X-C motif chemokine ligand 10 (CXCL10) and other inflammatory cytokines except Interferon gamma (IFN-gamma) compared to Cohort 2. Remarkable difference in CXCL-10 levels was noted between the groups and healthy volunteers had the lowest levels. No significant difference in IFN-gamma was noted between cohorts and the levels quickly depleted over the course of the infection.Conclusion: Our analysis confirms that neutralizing antibodies do not correlate with lessened COVID-19 disease severity. Severe COVID-19 infection is secondary to ineffective innate immunity associated with immune overshoot. CXCL10 serves as a major component in triggering the cytokine storm that is a hallmark of SARS-CoV-2 infections. Our findings show an association between high levels of CXCL10 and more severe COVID-19 infection. There does not seem to be any significant correlation with disease severity and IFN-gamma levels. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Characterizing Serum Cytokine Levels in Idiopathic Multicentric Castleman Disease Reveals Increased Chemokines and a Potential Signature Compared to Related Diseases

Idiopathic multicentric Castleman disease (iMCD) is a heterogeneous and life-threatening hematologic disorder with unknown etiology. It involves extensive lymphadenopathy with characteristic histopathology, inflammatory symptoms, and life-threatening cytokine-driven multi-organ failure, if inadequately treatment. Diagnosis requires the presence of histopathological, clinical, laboratory, and radiologic findings as well as exclusion of other related diseases including infectious, autoimmune, and lymphoproliferative disorders. Despite these guidelines, definitive diagnosis remains challenging as histopathological changes, clinical features, and laboratory abnormalities are non-specific. Given that iMCD can be aggressive and life-threatening, timely diagnosis is crucial, and specific diagnostic biomarkers are needed. Interleukin-6 (IL-6) is a known disease driver in a portion of patients, but it is not consistently elevated at diagnosis and characterization of other cytokines has not been systematically performed. Previously, a plasma proteomics study identified upregulation of multiple cytokines, including several chemokines, such as C-X-C Motif Chemokine Ligand 13 (CXCL13) and C-C motif ligand 21 (CCL21), during disease flare in a small cohort. We sought to investigate whether these findings would be replicated in a larger cohort and to identify cytokines that could help to improve diagnosis of iMCD.Herein, we analyzed serum samples from 88 iMCD patients, 42 healthy donors, and 20 patients each with rheumatoid arthritis (RA), Hodgkin lymphoma (HL), and a subtype of multicentric Castleman disease caused by infection with human herpes virus 8 (HHV8+MCD). 1300 analytes were quantified by SomaLogic SOMASCAN; Uniprot database was used to select the 159 quantified cytokines for analysis. Data were log2 normalized and capped at the 2.5 th and 97.5 th percentiles. Linear models were used to identify significant differences among disease groups, with p values adjusted by Benjamini & Hochberg. Hierarchical clustering was performed using complete linkage.Of the 159 cytokines quantified, 54 (34%) were identified as significantly different between iMCD and healthy donors. The most upregulated cytokine was CXCL13 with a log2 fold-change (FC) of 1.7 (p<0.0001). The chemokines CCL21 (FC: 1.3, p<0.0001) and CCL23 (FC: 0.87, p<0.0001) were also noted among the top 10 most upregulated cytokines, consistent with the earlier plasma proteomic study. Of note, IL-6 (FC: 0.35, p=0.039) was also found, but it ranked 31 out of 54 in log2 FC magnitude. We next sought to compare cytokine elevation in iMCD to related disorders. Hierarchical clustering of all 159 cytokines appeared to differentiate iMCD from RA, HL, and HHV8+MCD (Figure 1), revealing a cluster with 72/88 (82%) iMCD and 4/60 (6%) related disease patients versus another with 16/88 (18%) iMCD and 56/60 (93%) related disease patients. Given this, we used linear models to test for significant differences in protein expression between iMCD and related diseases. We identified 12 cytokines that were significantly different between iMCD and each comparator disease (Table 1). Of these, 10 cytokines all trended in the positive direction in iMCD versus each comparator disease. CCL21 was again noted among this group and had the highest average FC for all three groups.Herein we validate earlier findings that cytokines, particularly chemokines are significantly upregulated in iMCD. While previous results compared disease flare to disease remission in a small pilot cohort, our patient sample is >10 times larger, represents a broader spectrum of disease severity, and is compared to a set of healthy donors and related diseases. Unbiased hierarchical clustering was able to separate iMCD from other diseases, and linear models identified specific cytokines that are significantly different in iMCD compared to each RA, HL, and HHV8+MCD. Further validation is need to assess whether a cytokine panel can differentiate iMCD from other related diseases, which would be crucial for timely diagnosis and treatment. Of note, CXCL13 and CCL21 are primarily produced by follicular dendritic cells and fibroblastic reticular cells, stromal cells responsible for coordinating B cell and T cell trafficking in the lymph node, respectively. Dysregulation of these cells may contribute to the dysmorphic appearance of lymph nodes and pathogenesis in iMCD. [Display omitted] DisclosuresFajgenbaum: EUSA Pharma: Research Funding; Pfizer: Other: Study drug for clinical trial of sirolimus; N/A: Other: Holds pending provisional patents for ‘Methods of treating idiopathic multicentric Castleman disease with JAK1/2 inhibition’ and ‘Discovery and validation of a novel subgroup and therapeutic target in idiopathic multicentric Castleman disease’.

Dihydroartemisinin attenuates osteoclast formation and bone resorption via inhibiting the NF‑κB, MAPK and NFATc1 signaling pathways and alleviates osteoarthritis.

Osteoarthritis (OA) is a chronic, progressive and degenerative disease, and its incidence is increasing on a yearly basis. However, the pathological mechanism of OA at each stage is still unclear. The present study aimed to explore the underlying mechanism of dihydroartemisinin (DHA) in terms of its ability to inhibit osteoclast activation, and to determine its effects on OA in rats. Bone marrow-derived macrophages were isolated as osteoclast precursors. In the presence or absence of DHA, osteoclast formation was assessed by tartrate-resistant acid phosphatase (TRAP) staining, cell viability was assessed by Cell Counting Kit-8 assay, the presence of F-actin rings was assessed by immunofluorescence, bone resorption was determined by bone slices, luciferase activities of NF-κB and nuclear factor of activated T cell cytoplasmic 1 (NFATc1) were determined using luciferase assay kits, the protein levels of biomolecules associated with the NF-κB, MAPK and NFATc1 signaling pathways were determined using western blotting, and the expression of genes involved in osteoclastogenesis were measured using reverse transcription-quantitative PCR. A knee OA rat model was designed by destabilizing the medial meniscus (DMM). A total of 36 rats were assigned to three groups, namely the sham-operated, DMM + vehicle and DMM + DHA groups, and the rats were administered DHA or DMSO. At 4 and 8 weeks postoperatively, the micro-architecture of the subchondral bone was analyzed using micro-CT, the thickness of the cartilage layers was calculated using H&E staining, the extent of cartilage degeneration was scored using Safranin O-Fast Green staining, TRAP-stained osteoclasts were counted, and the levels of receptor activator of NF-κB ligand (RANKL), C-X-C-motif chemokine ligand 12 (CXCL12) and NFATc1 were measured using immunohistochemistry. DHA was found to inhibit osteoclast formation without cytotoxicity, and furthermore, it did not affect bone formation. In addition, DHA suppressed the expression levels of NF-κB, MAPK, NFATc1 and genes involved in osteoclastogenesis. Progressive cartilage loss was observed at 8 weeks postoperatively. Subchondral bone remodeling was found to be dominated by bone resorption accompanied by increases in the levels of RANKL, CXCL12 and NFATc1 during the first 4 weeks. DHA was found to delay OA progression by inhibiting osteoclast formation and bone resorption during the early phase of OA. Taken together, the results of the present study demonstrated that the mechanism through which DHA could inhibit osteoclast activation may be associated with the NF-κB, MAPK and NFATc1 signaling pathways, thereby indicating a potential novel strategy for OA treatment.

Dephosphorylation of Caveolin-1 Controls C-X-C Motif Chemokine Ligand 10 Secretion in Mesenchymal Stem Cells to Regulate the Process of Wound Healing.

Mesenchymal stem cells (MSCs) secrete cytokines in a paracrine or autocrine manner to regulate immune response and tissue regeneration. Our previous research revealed that MSCs use the complex of Fas/Fas-associated phosphatase-1 (Fap-1)/caveolin-1 (Cav-1) mediated exocytotic process to regulate cytokine and small extracellular vesicles (EVs) secretion, which contributes to accelerated wound healing. However, the detailed underlying mechanism of cytokine secretion controlled by Cav-1 remains to be explored. We show that Gingiva-derived MSCs (GMSCs) could secrete more C-X-C motif chemokine ligand 10 (CXCL10) but showed lower phospho-Cav-1 (p-Cav-1) expression than skin-derived MSCs (SMSCs). Moreover, dephosphorylation of Cav-1 by a Src kinase inhibitor PP2 significantly enhances CXCL10 secretion, while activating phosphorylation of Cav-1 by H2O2 restraints CXCL10 secretion in GMSCs. We also found that Fas and Fap-1 contribute to the dephosphorylation of Cav-1 to elevate CXCL10 secretion. Tumor necrosis factor-α serves as an activator to up-regulate Fas, Fap-1, and down-regulate p-Cav-1 expression to promote CXCL10 release. Furthermore, local applying p-Cav-1 inhibitor PP2 could accelerate wound healing, reduce the expression of α-smooth muscle actin and increase cleaved-caspase 3 expression. These results indicated that dephosphorylation of Cav-1 could inhibit fibrosis during wound healing. The present study establishes a previously unknown role of p-Cav-1 in controlling cytokine release of MSC and may present a potential therapeutic approach for promoting scarless wound healing.

Diagnostic Value of Multiple Serum Biomarkers for Vancomycin-Induced Kidney Injury.

Acute kidney injury (AKI) is a major contributor to in-hospital morbidity and mortality. Vancomycin, one of the most commonly used antibiotics in a clinical setting, is associated with AKI, with its incidence ranging up to 43%. Despite the high demand, few studies have investigated serum biomarkers to detect vancomycin-induced kidney injury (VIKI). Here, we evaluated the diagnostic value of nine candidate serum biomarkers for VIKI. A total of 23,182 cases referred for vancomycin concentration measurement from January 2018 to December 2019 were screened and 28 subjects with confirmed VIKI were enrolled (VIKI group). Age- and sex- matched control group consisted of 21 subjects who underwent vancomycin therapy without developing VIKI (non-VIKI group), and 23 healthy controls (HC group). The serum concentrations of clusterin, retinol binding protein 4 (RBP4), interleukin-18 (IL-18), tumor necrosis factor receptor 1 (TNF-R1), C-X-C motif chemokine ligand 10 (CXCL10), neutrophil gelatinase-associated lipocalin (NGAL), osteopontin, trefoil factor-3 (TFF3), and cystatin C were compared among the three groups, and their correlations with estimated glomerular filtration rate (eGFR) and diagnostic values for VIKI were assessed. All of the biomarkers except clusterin and RBP4 exhibited significant elevation in the VIKI group. Serum TFF3, cystatin C, TNF-R1, and osteopontin demonstrated an excellent diagnostic value for VIKI (TFF3, area under the curve (AUC) 0.932; cystatin C, AUC 0.917; TNF-R1, AUC 0.866; osteopontin, AUC 0.787); and except osteopontin, a strong negative correlation with eGFR (TFF3, r = −0.71; cystatin C, r = −0.70; TNF-R1, r = −0.60). IL-18, CXCL10, and NGAL showed weak correlation with eGFR and moderate diagnostic value for VIKI. This study tested multiple serum biomarkers for VIKI and showed that serum TFF3, cystatin C, TNF-R1, and osteopontin could efficiently discriminate VIKI patients. Further studies are warranted to clarify the diagnostic value of these biomarkers in VIKI.

Human hepatocyte-derived extracellular vesicles attenuate the carbon tetrachloride-induced acute liver injury in mice

Acute liver injury (ALI) induced by chemicals or viruses can progress rapidly to acute liver failure (ALF), often resulting in death of patients without liver transplantation. Since liver transplantation is limited due to a paucity of donors, expensive surgical costs, and severe immune rejection, novel therapies are required to treat liver injury. Extracellular vesicles (EVs) are used for cellular communication, carrying RNAs, proteins, and lipids and delivering them intercellularly after being endocytosed by target cells. Recently, it was reported that EVs secreted from human hepatocytes have an ability to modulate the immune responses; however, these roles of EVs secreted from human hepatocytes were studied only with in vitro experiments. In the present study, we evidenced that EVs secreted from human hepatocytes attenuated the CCL4-induced ALI by inhibiting the recruitment of monocytes through downregulation of chemokine receptor in the bone marrow and recruitment of neutrophils through the reduction of C-X-C motif chemokine ligand 1 (CXCL1) and CXCL2 expression levels in the liver.

Potential of C-X-C motif chemokine ligand 1/8/10/12 as diagnostic and prognostic biomarkers in idiopathic pulmonary arterial hypertension.

This study aimed to evaluate the clinical role of C-X-C motif chemokine ligand (CXCL) family members in idiopathic pulmonary arterial hypertension (IPAH) patients. CXCL1, CXCL8, CXCL10 and CXCL12 expressions in the serum samples of IPAH patients (N = 39) and age-/gender-matched controls (N = 40) were detected by enzyme-linked immunosorbent assay. In IPAH patients, clinical features were collected, and survival information was documented. CXCL1 (P < 0.001), CXCL8 (P = 0.001), CXCL10 (P < 0.001) and CXCL12 (P < 0.001) were increased in IPAH patients compared with controls, and receiver's operating characteristic curves showed that their combination was highly correlated with IPAH risk (area under curve: 0.881, 95% confidence interval: 0.805-0.958). Meanwhile, CXCL1 was positively correlated with mean pulmonary artery pressure (mPAP) (P = 0.029) and high-sensitive C-reactive protein (HsCRP) (P = 0.015); CXCL8 was positively correlated with mPAP (P = 0.044) and HsCRP (P = 0.018) but negatively correlated with 6-minute walk test (6MWT) distance (P = 0.029); CXCL10 was positively correlated with mean right artery pressure (P = 0.002); and CXCL12 was positively correlated with World Health Organization functional class (P = 0.047), mPAP (P = 0.009), pulmonary vascular resistance (P = 0.004) and HsCRP (P = 0.003) but negatively correlated with 6MWT distance (P = 0.003) in IPAH patients. Moreover, CXCL12 was negatively correlated with overall survival (OS) (P = 0.025), whereas CXCL1, CXCL8 and CXCL10 only showed minor tendencies to be negatively correlated with OS in IPAH patients without statistical significance (all P > 0.05). CXCL1, CXCL8, CXCL10 and CXCL12 associate with increased IPAH risk, unfavourable clinical features; besides, CXCL12 correlates with worse OS in IPAH patients.

The Involvement of CXC Motif Chemokine Ligand 10 (CXCL10) and Its Related Chemokines in the Pathogenesis of Coronary Artery Disease and in the COVID-19 Vaccination: A Narrative Review.

Coronary artery disease (CAD) and coronary heart disease (CHD) constitute two of the leading causes of death in Europe, USA and the rest of the world. According to the latest reports of the Iranian National Health Ministry, CAD is the main cause of death in Iranian patients with an age over 35 years despite a significant reduction in mortality due to early interventional treatments in the context of an acute coronary syndrome (ACS). Inflammation plays a fundamental role in coronary atherogenesis, atherosclerotic plaque formation, acute coronary thrombosis and CAD establishment. Chemokines are well-recognized mediators of inflammation involved in several bio-functions such as leucocyte migration in response to inflammatory signals and oxidative vascular injury. Different chemokines serve as chemo-attractants for a wide variety of cell types including immune cells. CXC motif chemokine ligand 10 (CXCL10), also known as interferon gamma-induced protein 10 (IP-10/CXLC10), is a chemokine with inflammatory features whereas CXC chemokine receptor 3 (CXCR3) serves as a shared receptor for CXCL9, 10 and 11. These chemokines mediate immune responses through the activation and recruitment of leukocytes, eosinophils, monocytes and natural killer (NK) cells. CXCL10, interleukin (IL-15) and interferon (IFN-g) are increased after a COVID-19 vaccination with a BNT162b2 mRNA (Pfizer/BioNTech) vaccine and are enriched by tumor necrosis factor alpha (TNF-α) and IL-6 after the second vaccination. The aim of the present study is the presentation of the elucidation of the crucial role of CXCL10 in the patho-physiology and pathogenesis of CAD and in identifying markers associated with the vaccination resulting in antibody development.

MiR-223 is increased in lungs of patients with COPD and modulates cigarette smoke-induced pulmonary inflammation.

Since microRNA (miR)-223-3p modulates inflammatory responses and chronic obstructive pulmonary disease (COPD) is associated with amplified pulmonary inflammation, we hypothesized that miR-223-3p plays a role in COPD pathogenesis. Expression of miR-223-3p was measured in lung tissue of two independent cohorts with patients with GOLD stage II-IV COPD, never smokers, and smokers without COPD. The functional role of miR-223-3p was studied in deficient mice and on overexpression in airway epithelial cells from COPD and controls. We observed higher miR-223-3p levels in patients with COPD stage II-IV compared with (non)-smoking controls, and levels were associated with higher neutrophil numbers in bronchial biopsies of patients with COPD. MiR-223-3p expression was also increased in lungs and bronchoalveolar lavage of cigarette smoke (CS)-exposed mice. CS-induced neutrophil and monocyte lung infiltration was stronger in miR-223-deficient mice on acute (5 days) exposure, but attenuated on subchronic (4 wk) exposure. Additionally, miR-223 deficiency attenuated acute and subchronic CS-induced lung infiltration of dendritic cells and T lymphocytes. Finally, in vitro overexpression of miR-223-3p in non-COPD airway epithelial cells suppressed C-X-C motif chemokine ligand 8 (CXCL8) and granulocyte monocyte-colony stimulation factor (GM-CSF) secretion and gene expression of the proinflammatory transcription factor TRAF6. Importantly, this suppressive effect of miR-223-3p was compromised in COPD-derived cultures. In conclusion, we demonstrate that miR-223-3p is increased in lungs of patients with COPD and CS-exposed mice and is associated with neutrophilic inflammation. In vivo data indicate that miR-223 acts as negative regulator of acute CS-induced neutrophilic and monocytic inflammation. In vitro data suggest that miR-223-3p does so by suppressing proinflammatory airway epithelial responses, which is less effective in COPD epithelium.