IFN-γ Inducible Protein Research Articles

Interferon-gamma driven elevation of CXCL9: a new sepsis endotype independently associated with mortality

Endotype classification becomes the cornerstone of understanding sepsis pathogenesis. Macrophage activation-like syndrome (MALS) and immunoparalysis are the best recognized major endotypes, so far. Interferon-gamma (IFNγ) action on tissue macrophages stimulates the release of the cytotoxic chemokine CXCL9. It was investigated if this mechanism may be an independent sepsis endotype. In this cohort study, 14 patient cohorts from Greece, Germany and Italy were studied. The cohorts were 2:1 randomly split into discovery and validation sets. Sepsis was defined by the Sepsis-3 definitions and blood was sampled the first 24h from meeting the Sepsis-3 definitions. Concentrations of IFNγ, CXCL9, IP-10 (IFNγ induced protein-10), soluble CD163 and ferritin were measured. The endotype of IFNγ-driven sepsis (IDS) was defined in the discovery set as the combination of a) blood IFNγ above a specified cut-off associated with the minimal risk for immunoparalysis (defined as ≥8000 HLA-DR receptors on CD45/CD14-monoytes); and b) increase of CXCL9. Results were compared to the validation set. 5503 patients were studied; 3670 in the discovery set and 1833 in the validation set. IDS was defined as IFNγ more than 3pg/ml and CXCL9 more than 2200pg/ml. The frequency of IDS in the discovery set was 19.9% (732 patients; 95% confidence intervals-CIs 18.7-21.3%) and in the validation set 20.0% (366 patients; 95% CIs 18.2-21.9%). Soluble CD163, a marker of macrophage activation, was greater in IDS and IDS had features distinct from MALS. The mortality in IDS patients was 43.0% (315 patients; 95% CIs 39.5-46.6%) in the discovery set and 40.4% in the validation set (148 patients; 95% CIs 35.5-45.5%) (p=0.44 compared to patients of the discovery set). IDS was an independent risk factor for death in the presence of other endotypes, severity scores and organ dysfunctions of the multivariate model [hazard ratio 1.71 (95% CIs 1.45-2.01) in the discovery set and 1.70 (95% CIs 1.34-2.16) in the validation set]. Decreases of IFNγ and CXCL9 blood levels within the first 72h were associated with better outcome. IDS is a new sepsis endotype independently associated with unfavorable outcome. Hellenic Institute for the Study of Sepsis; Horizon 2020 project ImmunoSep; Swedish Orphan BioVitrum AB (publ) and German Federal Ministry of Education and Research.

MicroRNA-296-5p Expression in COVID-19 Patients and its Relationship with Inflammatory Cytokines

Objectives: The cytokine storm, triggered by the activation of certain pro-inflammatory genes in the second phase of COVID-19, is associated with severe acute respiratory disorder. Evidence suggests that microRNAs (miR) and cytokine levels can play pivotal roles in host cell antiviral defense mechanisms. This study aimed to investigate the changes in IFN-γ inducible protein 10 (IP-10) and miR-296-5p expression, as well as their relationship with some inflammatory cytokines and biochemical variables in COVID-19 patients. Methods: This retrospective single-center study was conducted on 30 COVID-19 patients and 30 controls. The expression of miR-296-5p and IP-10 genes in peripheral blood mononuclear cells (PBMCs) was evaluated using real-time PCR. Serum levels of IL-6, TNF-α, and CRP were measured by ELISA. Results: Higher expression levels of miR-296-5p and IP-10 genes were observed in COVID-19 patients compared to controls (P=0.001). Furthermore, IP-10, IL-6, and TNF-α levels were significantly higher (PP<0.01) in COVID-19 patients than in controls. The results also showed positive correlations between miR-296-5p expression and serum levels of IL-6, CRP, and TNF-α in patients with COVID-19. ROC curve analysis of miR[1]296-5p in COVID-19 patients showed an area under the curve of 0.830, 95% CI (0.658-0.815), P<0.001, with an optimal cut-off point of 0.32965. Conclusion: Our results suggest a regulatory role for miR-296-5p in cytokine secretion in COVID-19. The results indicate that the expression of miR-296-5p and IP-10 genes in PBMCs might serve as convenient novel biomarkers for the prognosis of COVID-19.

Association of the Reduced Levels of Monocyte Chemoattractant Protein-1 with Herpes Zoster in Rheumatoid Arthritis Patients Treated with Janus Kinase Inhibitors in a Single-Center Cohort.

Anti-interferon (IFN)-γ autoantibodies are linked to varicella zoster virus (VZV) infection. Given the elevated risks of herpes zoster (HZ) in rheumatoid arthritis (RA) patients treated with Janus kinase inhibitors (JAKis), we aimed to examine the relationship between anti-IFN-γ autoantibodies with HZ development in JAKi-treated patients. Serum titers of anti-IFN-γ autoantibodies, plasma levels of IFN-γ, monocyte chemoattractant protein-1 (MCP-1), and IFN-γ-inducible protein-10 (IP-10) were measured by ELISA. Among the 66 enrolled RA patients, 24 developed new-onset HZ. Significantly lower MCP-1 levels were observed in patients with HZ compared to those without (median, 98.21 pg/mL, interquartile range (IQR) 77.63-150.30 pg/mL versus 142.3 pg/mL, IQR 106.7-175.6 pg/mL, p < 0.05). There was no significant difference in anti-IFN-γ titers, IFN-γ levels, or IP-10 levels between patients with and without HZ. Three of 24 patients with HZ had severe HZ with multi-dermatomal involvement. Anti-IFN-γ titers were significantly higher in patients with severe HZ than in those with non-severe HZ (median 24.8 ng/mL, IQR 21.0-38.2 ng/mL versus 10.5 ng/mL, IQR 9.9-15.0 ng/mL, p < 0.005). Our results suggest an association between reduced MCP-1 levels and HZ development in JAKi-treated RA patients. High-titer anti-IFN-γ autoantibodies may be related to severe HZ in these patients.

Nucleic Acid and Nanomaterial Synergistic Amplification Enables Dual Targets of Ultrasensitive Fluorescence Quantification to Improve the Efficacy of Clinical Tuberculosis Diagnosis.

Interferon-γ (IFN-γ) release assays (IGRAs) are constrained by the limited diagnostic performance of a single indicator and the excessive Mycobacterium tuberculosis (Mtb) antigen stimulation time. This study presents a simultaneous, homogeneous, rapid, and ultrasensitive fluorescence quantification strategy for IFN-γ and IFN-γ-induced protein 10 (IP-10). This method relies on the high-affinity binding of aptamers to IFN-γ and IP-10, the enzyme-free catalytic hairpin assembly reaction, and the heightened sensitivity of CdTe quantum dots to Ag+ and hairpin structure C-Ag+-C and carbon dots to Hg2+ and hairpin structure T-Hg2+-T. Under optimized conditions, the selectivity of IFN-γ and IP-10 was excellent, with a linear range spanning from 1 to 100 ag/mL and low limits of detection of 0.3 and 0.5 ag/mL, respectively. Clinical practicality was confirmed through testing of 57 clinical samples. The dual-indicator combination detection showed 92.8% specificity and 93.1% sensitivity, with an area under the curve of 0.899, representing an improvement over the single-indicator approach. The Mtb antigen stimulation time was reduced to 8 h for 6/7 clinical samples. These findings underscore the potential of our approach to enhance the efficiency and performance of a tuberculosis (TB) clinical diagnosis.

Synthetic Particulate Subunit Vaccines for the Prevention of Q Fever.

Coxiella burnetti is an intracellular bacterium that causes Q fever, a disease of worldwide importance. Q-VAX® , the approved human Q fever vaccine, is a whole cell vaccine associated with safety concerns. Here a safe particulate subunit vaccine candidate is developed that is ambient-temperature stable and can be cost-effectively manufactured. Endotoxin-free Escherichia coli is bioengineered to efficiently self-assemble biopolymer particles (BPs) that are densely coated with either strings of 18 T-cell epitopes (COX-BP) or two full-length immunodominant antigens (YbgF-BP-Com1) all derived from C. burnetii. BP vaccine candidates are ambient-temperature stable. Safety and immunogenicity are confirmed in mice and guinea pig (GP) models. YbgF-BP-Com1 elicits specific and strong humoral immune responses in GPs with IgG titers that are at least 1000 times higher than those induced by Q-VAX® . BP vaccine candidates are not reactogenic. After challenge with C. burnetii, YbgF-BP-Com1 vaccine leads to reduced fever responses and pathogen burden in the liver and the induction of proinflammatory cytokines IL-12 and IFN-γ inducible protein (IP-10) when compared to negative control groups. These data suggest that YbgF-BP-Com1 induces functional immune responses reducing infection by C. burnetii. Collectively, these findings illustrate the potential of BPs as effective antigen carrier for Q fever vaccine development.

Effects of a multispecies direct-fed microbial on gastrointestinal permeability during feed restriction in a growing heifer model

The objectives were to evaluate the effects of a 4-strain direct-fed microbial (DFM) on gastrointestinal tract (GIT) permeability and inflammation during feed restriction (FR) in heifers. Holstein heifers (n = 32; mean ± standard deviation; 295 ± 25 kg body weight; 287 ± 17 d of age) were used in an experiment conducted in 2 replicates (16/replicate). Heifers were randomly assigned to 1 of 2 top-dressed dietary treatments: (1) control (CON; 10 g/d dried lactose; n = 16) or (2) DFM containing a commercial blend of Lactobacillus animalis, Propionibacterium freudenreichii, Bacillus licheniformis, and Bacillus subtilis at 11.8 × 109 cfu/d (PRO; 10 g/d 4-strain DFM; n = 16). The trial consisted of 2 experimental periods (P): P1 (14 d) served as baseline for P2 (5 d), when all heifers were restricted to 40% of their P1 dry matter intake (DMI). On P1 d 12 and P2 d 2 and 5, GIT permeability was evaluated using oral chromium (Cr)-EDTA. By design, FR decreased DMI (60%) and body weight (∼18 kg) in all heifers. Regardless of treatment, during FR, all heifers had decreased circulating glucose, β-hydroxybutyrate, insulin, and l-lactate (4, 14, 45, and 19%, respectively), but increased nonesterified fatty acids, serum amyloid A, and haptoglobin (3.0-, 1.7-, and 5.0-fold, respectively). Circulating white blood cells, neutrophils, lymphocytes, and basophils decreased (4, 7, 5, and 6%, respectively), whereas eosinophils increased (41%) during P2 irrespective of dietary treatment. Circulating IFN-γ inducible protein-10 increased (23%) during FR compared with P1 regardless of treatment. Plasma Cr area under the curve increased in all heifers on d 2 and 5 (10 and 14%, respectively) of P2 relative to P1, but this was unaltered by dietary treatment. In summary, FR compromised GIT barrier function and stimulated an inflammatory response, but this did not appear to be ameliorated by PRO.

CTIM-11. MRNA AGGREGATES ELICIT RAPID IMMUNOLOGIC RESPONSE AND PSEUDOPROGRESSION IN GLIOBLASTOMA PATIENTS

Abstract BACKGROUND Glioblastoma immunotherapy trials remain limited by heterogeneity and the immunosuppressive tumor microenvironment (TME). To overcome these challenges, we developed a novel cancer immunotherapy that leverages use of mRNA lamellar aggregates (RNA-LPA) encoding for personalized glioblastoma antigens to simultaneously reprogram the GBM TME while inducing tumor specific immunity in the periphery. METHODS In a Phase I trial (PNOC020) with an embedded acceleration titration design (ATD) for patients with newly-diagnosed MGMT unmethylated glioblastoma, we sought to assess whether intravenous administration of RNA-LPAs encoding for pp65 mRNA (tumor associated antigen) mixed with personalized tumor mRNA (extracted and amplified from patient specific biopsies) could activate peripheral immunity while simultaneously reprogramming the GBM TME. All patients received surgical resection with adjuvant chemoradiation followed by escalating doses of RNA-LPA (0.625-1.5 µg/kg). RESULTS We have treated 3 patients on the ATD and one patient on the expanded Phase I trial. In all patients treated to date, RNA-LPAs elicited a rapid response (within hours) characterized by release of cytokines (IL-12, TNF-α, IFN-α), chemokines (CCL2, CCL4, CXCL9-10), increase in plasmacytoid dendritic cells and recruitment of peripheral blood mononuclear cells. Over time there was expansion of antigen specific T cells; T cell receptor (TCR) sequencing pre- and post-infusion demonstrated changes to the most prevalent clonotypes by ~10-20%. In the first subject treated on the expanded phase I trial, we observed significant immunologic response after the fourth vaccine, including 20-fold increase in IFN-γ inducible protein-10. One month after vaccine administration, there was marked increase in the enhancing areas on MRI, which on biopsy demonstrated no viable tumor cells and only reactive gliosis, necrosis, and lymphocytic infiltrates. CONCLUSION RNA-LPAs elicit rapid immune activation in the periphery and reprogram the GBM TME into a proinflammatory milieu as evidenced by tissue confirmed pseudoprogression.

Analysis of cytokines in bronchoalveolar lavage fluid in patients with checkpoint inhibitor pneumonitis and pulmonary infection: A case-control study.

The discovery of immune checkpoint inhibitors (ICIs) is a breakthrough in the field of cancer therapy. However, ICIs may cause immune-related adverse reactions, including checkpoint inhibitor-related pneumonitis (CIP). The aim of this study was to investigate cytokines in bronchoalveolar lavage fluid (BALF) of patients with CIP compared with patients with pulmonary infection and patients with cancer. We retrospectively analyzed 34 cytokine levels and T cell subsets in BALF supernatant samples from ICI-treated patients with CIP (n = 13), pulmonary infection (n = 10), and progressive cancer (n = 12). Cytokine levels and T cell subsets were compared among the three groups of patients. We observed significantly higher levels of IFN-γ-induced protein 10(IP-10) (p = 0.002), and percentage of CD3 + CD8 + T cells (p = 0.020) in BALF of patients with CIP compared with the other two groups. However, we found significantly lower levels of interleukin-21 (p = 0.008) in BALF of patients with progressive disease compared with the other two groups. Cytokine profile and character of cell subsets in BALF was helpful for the differential diagnosis of CIP. IP-10 may play an important role in pathophysiology for CIP and also be a potential therapeutic target.

High levels of pro-inflammatory SARS-CoV-2-specific biomarkers revealed by in vitro whole blood cytokine release assay (CRA) in recovered and long-COVID-19 patients.

Cytokines induced by SARS-CoV-2 infection play a crucial role in the pathophysiology of COVID-19 and hyperinflammatory responses have been associated with poor clinical outcomes, with progression to severe conditions or long-term subacute complications named as long-COVID-19. In this cross-sectional study, we aimed to evaluate a set of antigen-specific inflammatory cytokines in blood from recovered COVID-19 individuals or who suffered a post-acute phase of SARS-CoV-2 infection compared to healthy individuals with no history of COVID-19 exposition or infection. Interferon-gamma (IFN-γ), IFN-γ-induced protein 10 (IP-10), tumor necrosis factor (TNF), IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, and IL-17A were quantified by multiplex cytometric bead assay and enzyme-linked immunosorbent assay after stimulation of whole blood with recombinant Spike protein from SARS-CoV-2. Additionally, all participants have evaluated for anti-(S) protein-specific IgG antibodies. Clinical specimens were collected within two months of COVID-19 diagnosis. A total of 47 individuals were enrolled in the study, a median age of 43 years (IQR = 14.5), grouped into healthy individuals with no history of infection or exposure to SARS-CoV-2 (unexposed group; N = 21); and patients from the Health Complex of the Rio de Janeiro State University (UERJ), Brazil, who were SARS-CoV-2 positive by RT-PCR (COVID-19 group)-categorized as recovered COVID-19 (N = 11) or long-COVID-19 (N = 15). All COVID-19 patients presented at least one signal or symptom during the first two weeks of infection. Six patients were hospitalized and required invasive mechanical ventilation. Our results showed that COVID-19 patients had significantly higher levels of IFN-γ, TNF, IL-1β, IL-2, IL-6, IL-8, and IP-10 than the unexposed group. The long-COVID-19 group has presented significantly high levels of IL-1β and IL-6 compared to unexposed individuals, but not from recovered COVID-19. A principal-component analysis demonstrated 84.3% of the total variance of inflammatory-SARS-CoV-2 response in the first two components, and it was possible to stratify IL-6, TNF, IL-1β, IL-10, and IL-2 as the top-five cytokines which are candidates to discriminate COVID-19 group (including long-COVID-19 subgroup) and healthy unexposed individuals. We revealed important S protein-specific differential biomarkers in individuals affected by COVID-19, bringing new insights into the inflammatory status or SARS-CoV-2 exposition determination.

COVID-19 and the possible development of autoimmune thyroid diseases

In the midst of continuing coronavirus infection (COVID-19) there has been an increase in the incidence of various autoimmune pathologies. Particular attention to the potential relationship between coronavirus infection and autoimmune diseases is attracted by the positive therapeutic effect of the treatment of severe forms of COVID-19 with drugs used in the treatment of rheumatologically diseases.The results of the study should be the starting point for understanding the mechanisms of possible breakdown of immunological tolerance and the development of autoimmune thyroid diseases.AIM: To assess the risks of developing autoimmune thyroid disease after COVID-19, and to investigate the effect of therapy in the acute period on the possible development of autoimmune thyroid diseases.MATERIALS AND METHODS: This prospective comparative study included patients hospitalized at the National Medical Research Center for Endocrinology with a clinical and laboratory analysis of COVID-19 and bilateral polysegmental viral pneumonia (n=41). Patients with COVID-19 were divided into two subgroups: a subgroup of patients who received tocilizumab therapy in acute period (n=10), the second subgroup of patients who received symptomatic therapy during the acute period COVID-19 (n=31).To assess the functional status of the thyroid gland all patients underwent observation of the thyroid-stimulating hormone (TSH), free triiodothyronine (T3f), free thyroxine (T4f), antibodies to thyroperoxidase (Ab-TPO) and antibodies to the TSH receptor (Ab-recTSH).The concentrations of 27 signaling molecules in the blood serum were assessed by the technology of multiplex flow immunoassay using the Bio-Plex Pro Human Cytokine 27-plex Assay kit of cytokines and chemokines: interleukins-1b, -1ra, -2, 4-10, -12, -13, -15, -17 (IL-1b, IL-1ra, IL-2, IL - 4-10, IL-12, IL-13, IL-15, IL-17), Eotaxin, fibroblast growth factor (FGF), granulocyte- macrophage colony stimulating factor (GM-CSF), granulocyte colony stimulating factor (G -CSF), interferon-gamma (IFN-g), IFNγ-inducible protein 10 (IP-10), monocyte chemotactic protein-1 (MCP-1), also known as monocyte chemotactic and activating factor (MCAF), macrophage inflammatory protein -1 (MIP-1a and -1b), platelet growth factor BB (PDGF-bb), Regulated on Activation Normal T-cell Expressed and Secreted (RANTES), tumor necrosis factor-alpha (TNF-a), vascular endothelial growth factor (VEGF).All patients denied the presence of thyroid diseases, palpation of the thyroid gland revealed nodular formations in 5% of patients, and appropriate recommendations were given to patients.RESULTS: The overt hypothyroidism was detected in 2.4% of patients, subclinical - in 7.3% of patients in six months after the onset of coronavirus infection, and also found increased levels of the Ab-TPO in six months after recovery (p = 0.023 - Wilcoxon test). In the group of patients with increased Ab-TPO levels after COVID-19, statistically significantly high levels of IFN-g (p = 0.007), Eotaxin (p = 0.008) were obtained. An increased Ab-recTSH were revealed in the group of patients with severe COVID-19 who did not receive pathogenetic therapy with tocilizumab in the acute period (p = 0.046 - Mann-Whitney test).CONCLUSION: The results of our study and the scientific work of foreign colleagues demonstrate the potential risks of developing autoimmune thyroid diseases after a coronavirus infection. A close relationship was found between changes in the thyroid profile and hyperactivation of the immune system with hyperproduction of pro-inflammatory interleukins in COVID-19. This statement is confirmed by the revealed overt and subclinical hypothyroidism, as well as an increase in Ab- TPO levels in this group of patients after a coronavirus infection (p = 0.023 - Wilcoxon test) with a simultaneous persistent increased levels of some pro-inflammatory cytokines in dynamics, determined by autoimmune thyroiditis.The hypothesis of thyroid tissue damage by pro-inflammatory cytokines during COVID-19, as well as the hypothesis suggesting a protective effect on the development of autoimmune thyroid diseases by therapy with tocilizumab in the acute period were confirmed by increased levels of Ab-recTSH in patients with severe COVID-19 who did not receive tocilizumab in the acute period (p = 0.046 - Mann-Whitney test).

The oncolytic adenovirus XVir-N-31 joins forces with CDK4/6 inhibition augmenting innate and adaptive antitumor immunity in Ewing sarcoma.

Ewing sarcoma (EwS) is a highly malignant pediatric tumor characterized by a non-T cell-inflamed immune-evasive phenotype. When relapsed or metastasized, survival is poor, emphasizing the need for novel treatment strategies. Here, we analyze the novel combination approach using the YB-1-driven oncolytic adenovirus XVir-N-31 and CDK4/6 inhibition to augment EwS immunogenicity. In vitro, viral toxicity, replication, and immunogenicity were studied in several EwS cell lines. In vivo tumor xenograft models with transient humanization were applied to evaluate tumor control, viral replication, immunogenicity, and dynamics of innate as well as human T cells after treatment with XVir-N-31 combined with CDK4/6 inhibition. Furthermore, immunological features of dendritic cell maturation and T cell-stimulating capacities were assessed. The combination approach significantly increased viral replication and oncolysis in vitro, induced HLA-I upregulation, and interferon-gamma-induced protein 10 expression and enhanced maturation of monocytic dendritic cells with superior capacities to stimulate tumor antigen-specific T cells. These findings were confirmed in vivo showing tumor-infiltration by (1) monocytes with antigen-presenting capacities and M1 macrophage marker genes, (2) TReg suppression in spite of adenovirus infection (3) superior engraftment and (4) tumor-infiltration by human T cells. Consequently, survival was improved over controls with signs of an abscopal effect after combination treatment. The joint forces of the YB-1-driven oncolytic adenovirus XVir-N-31 and CDK4/6 inhibition induce therapeutically relevant local and systemic antitumor effects. Innate as well as adaptive immunity against EwS is boosted in this preclinical setting, pointing towards high therapeutic potential in the clinic.

High-titer anti-interferon-γ neutralizing autoantibodies linked to opportunistic infections in patients with adult-onset still's disease.

Neutralizing anti-interferon (IFN)-γ autoantibodies are linked to opportunistic infections (OIs). To explore the association between anti-IFN-γ autoantibodies and OIs in patients with adult-onset Still's disease (AOSD), we aimed to examine the ability of these autoantibodies to blockade signal transducer and activator of transcription (STAT1)-phosphorylation and chemokines production. Serum titers of anti-IFN-γ autoantibodies were quantified using ELISA in 29 AOSD and 22 healthy controls (HC). The detectable autoantibodies were verified with immunoblotting assay, and their neutralizing capacity against IFN-γ-signaling was evaluated with flow-cytometry analysis and immunoblotting. IFN-γ-mediated production of supernatant chemokines, including monocyte chemoattractant protein-1 (MCP-1) and IFN-γ inducible protein-10 (IP-10), were measured by ELISA. Among 29 AOSD patients, high titers of anti-IFN-γ neutralizing autoantibodies were detectable in two patients with OIs. Immunoblotting assay revealed more effective inhibition of STAT1-phosphorylation in THP-1 cells treated with sera from autoantibody-positive AOSD patients (56.7 ± 34.79%) compared with those from HC (104.3 ±29.51%), which was also demonstrated in flow-cytometry analysis (47.13 ± 40.99 vs. 97.92 ± 9.48%, p < 0.05). Depleted serum IgG from anti-IFN-γ autoAbs-positive AOSD patients with OIs restored phosphorylated STAT-1 upon IFN-γ treatment. Sera from autoantibody-positive AOSD patients more effectively inhibited IFN-γ-mediated production of MCP-1 (45.65 pg/ml) and IP-10 (22.44 pg/ml) than sera from HC (263.1 pg/ml and 104.0 pg/ml, both p < 0.05). Serum samples showing the strongest inhibition of IFN-γ-signaling were from two patients with high-titer autoantibodies and OIs. AOSD patients have a high positive rate and titers of anti-IFN-γ autoantibodies. The remarkable blockade effect of high-titer autoantibodies on IFN-γ-mediated STAT1-phosphorylation and chemokines could make these patients susceptible to OIs.

Recombinant Klotho attenuates IFNγ receptor signaling and SAMHD1 expression through blocking NF-κB translocation in glomerular mesangial cells.

Interferon gamma (IFNγ) is a cytokine implicated in the pathogenesis of autoimmune diseases. SAM and HD domain-containing protein 1 (SAMHD1) is an IFNγ-inducible protein that modulates cellular dNTP levels. Mutations in the human SAMHD1 gene cause Aicardi-Goutières (AG) syndrome, an autoimmune disease sharing similar clinical features with systemic lupus erythematosus (SLE). Klotho is an anti-inflammatory protein which suppresses aging through multiple mechanisms. Implication of Klotho in autoimmune response is identified in rheumatologic diseases such as SLE. Little information exists regarding the effect of Klotho in lupus nephritis, one of the prevalent symptoms of SLE. The present study verified the effect of IFNγ on SAMHD1 and Klotho expression in MES-13 glomerular mesangial cells, a special cell type in glomerulus that is critically involved in lupus nephritis. IFNγ upregulated SAMHD1 expression in MES-13 cells through the Janus kinase-signal transducer and activator of transcription 1 (JAK-STAT1) and the nuclear factor kappa B (NFκB) signaling pathways. IFNγ decreased Klotho protein expression in MES-13 cells. Treatment of MES-13 cells with recombinant Klotho protein inhibited SAMHD1 expression by blocking IFNγ-induced NFκB nuclear translocation, but showed no effect on JAK-STAT1 signaling. Collectively, our findings support the protective role of Klotho in attenuating lupus nephritis through the inhibition of IFNγ-induced SAMHD1 expression and IFNγ downstream signaling in MES-13 cells.

1115. Effect of polymerized type I collagen in hyperinflammation of adult outpatients with symptomatic COVID-19: a double blind, randomised, placebo-controlled clinical trial

Abstract Background Currently, therapeutic options for outpatients with COVID-19 are limited, in Mexico Polymerized Collagen type I (PCTI) has been tested as a useful option. Methods Double-blind, randomised, placebo-controlled clinical trial of PTIC vs placebo. To evaluate the safety, efficacy and effect of the intramuscular administration of polymerized type I collagen (PTIC) on hyperinflammation, oxygen saturation and symptom improvement in adult outpatients with symptomatic COVID-19. Eighty-nine adult participants with a confirmed COVID-19 diagnosis and symptom onset within the 7 days preceding recruitment were included from August 31, 2020 to November 7, 2020 and followed for 12 weeks. Final date of follow-up was February 4, 2021. Patients were randomly assigned to receive either 1.5 ml of PTIC intramuscularly every 12 h for 3 days and then every 24 h for 4 days (n=45), or matching placebo (n=44). Results Of 89 patients who were randomised, 87 (97.8%) were included in an intention-to-treat analysis; 37 (41.6%) were male and mean age was 48.5±14.0 years. The IP-10 levels decreased 75% in the PTIC group and 40% in the placebo group vs baseline. The comparison between treatment vs placebo was also statistically significant (P=0.0047). The IL-8 (44%, P=0.045), M-CSF (25%, P=0.041) and IL-1Ra (36%, P=0.05) levels were also decreased in the PTIC group vs baseline. Mean oxygen saturation ≥92% was achieved by 40/44 (90%), 41/42 (98%) and 40/40 (100%) of participants that received PTIC at 8, 15 and 97 days of follow-up vs 29/43 (67%), 31/39 (80%) and 33/37 (89%) of patients treated with placebo (P=0.001). The unadjusted accelerated failure time model showed that patients treated with PTIC achieved the primary outcome 2.70-fold faster (P&amp;lt; 0.0001) than placebo. In terms of risk, the group of patients treated with PTIC had a 63% lower risk of having a mean oxygen saturation &amp;lt; 92% vs placebo (P&amp;lt; 0.0001). Symptom duration in patients treated with PTIC was reduced by 6.1±3.2 days vs placebo. No differences in adverse effects were observed between the groups at 8, 15 and 97 days of follow-up. Conclusion Treatment with PTIC down-regulated IP-10, IL-8, M-CSF and IL-Ra levels, which could explain the PTIC effect on the higher proportion of patients with mean SaO2 ≥92% and a shorter duration of symptoms as compared with placebo. Serum cytokine and chemokine levels of SARS-CoV2-infected symptomatic outpatients at baseline and day 8 post-treatment with PTIC or placebo. Data are expressed as median with 95% confidence. (A) IP-10, IFN-γ inducible protein-10; (B) IL-8, Interleukin-8; (C) M-CSF, Macrophage colony-stimulating factor; (D) IL-1Ra, IL-1 receptor antagonist; (E) TRAIL, TNF-related apoptosis inducing ligand; and (F) Forest plot (95% confidence intervals). (A) Probability of oxygen saturation 92% or greater while breathing ambient air. (B) Accelerated time failure model for oxygen saturation 92% or greater while breathing ambient air among polymerised type I collagen and placebo. Disclosures All Authors: No reported disclosures.

Association of immunological parameters with aortic dilatation in giant cell arteritis: a cross-sectional study

Aortic dilatation (AD) occurs in up to 30% of patients with giant cell arteritis (GCA). Reliable biomarkers for AD development, however, are still absent. The aim of this exploratory study was to evaluate whether immunological parameters are associated with the occurrence of AD in GCA. Cross-sectional study on 20 GCA patients with AD, 20 GCA patients without AD, and 20 non-GCA controls without AD measuring leukocytes, neutrophils, lymphocytes, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), serum amyloid A (SAA), interferon (IFN)-α, IFN-γ, IFN-γ-induced protein 10 (IP-10), interleukin (IL) 5, IL-8, IL-10, IL-17A, IL-18, IL-1 receptor antagonist, tumor necrosis factor (TNF)-α, platelet-derived growth factor (PDGF), L-selectin, P-selectin, and soluble intercellular adhesion molecule 1 (sICAM-1). AD was measured by aortic contrast-enhanced computed tomography and defined by enlargement of the aorta above population-based aortic diameters adjusted by age, gender, and body surface area. No significant differences were observed between GCA patients with AD and GCA patients without AD concerning levels of leukocytes, neutrophils, lymphocytes, CRP, ESR, SAA, IL-8, IL-18, PDGF, IP-10, selectins, and sICAM-1. Values of IFN-α, IFN-γ, IL-5, IL-10, IL-17A, IL-1 receptor antagonist, and TNF-α were all below the detection limits in more than 70% of subjects. Lymphocytes and CRP revealed positive correlations with the diameter of the thoracic descending aorta. Immunological parameters were not useful to conclude on the presence of AD in GCA. Further studies are required to test if CRP and lymphocytes may be useful to predict future development of AD in GCA.

Antiviral effect of vesatolimod (GS-9620) against foot-and-mouth disease virus both in vitro and invivo

Foot-and-mouth disease (FMD) is an acute contagious disease of cloven-hoofed animals such as cows, pigs, sheep, and deer. The current emergency FMD vaccines, to induce early protection, have limited use, as their protective effect in pigs does not begin until 7 days after vaccination. Therefore, the use of antiviral agents would be required for reducing the spread of foot-and-mouth disease virus (FMDV) during outbreaks. Vesatolimod (GS-9620), a toll-like receptor 7 agonist, is an antiviral agent against various human disease-causing viruses. However, its antiviral effect against FMDV has not been reported yet. The aim of this study was to investigate the antiviral effects of GS-9620 against FMDV both in vitro and in vivo. The inhibitory effect of GS-9620 on FMDV in swine cells involved the induction of porcine interferon (IFN)-α and upregulation of interferon-simulated genes. Protective effect in mice injected with GS-9620 against FMDV was maintained for 5 days after injection, and cytokines such as IFN-γ, interleukin (IL)-12, IL-6, and IFN-γ inducible protein-10 could be detected following the treatment with GS-9620. Furthermore, the combination of GS-9620 with an FMD-inactivated vaccine was found to be highly effective for early protection in mice. Overall, we suggest GS-9620 as a novel and effective antiviral agent for controlling FMDV infection.

IFNγ-induced PD-L1 expression in ovarian cancer cells is regulated by JAK1, STAT1 and IRF1 signaling

Expression of the immune checkpoint programmed death ligand-1 (PD-L1) is increased in ovarian cancer (OC) and correlates with poor prognosis. Interferon-γ (IFNγ) induces PD-L1 expression in OC cells, resulting in their increased proliferation and tumor growth, but the mechanisms that regulate the PD-L1 expression in OC remain unclear. Here, we show that the IFNγ-induced PD-L1 expression in OC cells is associated with increased levels of STAT1, Tyr-701 pSTAT1 and Ser-727 pSTAT1. Suppression of JAK1 and STAT1 significantly decreases the IFNγ-induced PD-L1 expression in OC cells, and STAT1 overexpression increases the IFNγ-induced PD-L1 expression. In addition, IFNγ induces expression of the transcription factor interferon regulatory factor 1 (IRF1) and IRF1 suppression attenuates the IFNγ-induced gene and protein levels of PD-L1. Chromatin immunoprecipitation results show that IFNγ induces PD-L1 promoter acetylation and recruitment of STAT1, Ser-727 pSTAT1 and IRF1 in OC cells. Together, these findings demonstrate that the IFNγ-induced PD-L1 expression in OC cells is regulated by JAK1, STAT1, and IRF1 signaling, and suggest that targeting the JAK1/ STAT1/IRF1 pathway may provide a leverage to regulate the PD-L1 levels in ovarian cancer.

Interferon‐γ Induced PD‐L1 Expression in Ovarian Cancer Cells is Regulated by IRF1 Signaling

The immune checkpoint programmed death ligand‐1 (PD‐L1) is highly expressed in cancer cells, including ovarian cancer (OC) cells. High PD‐L1 expression in ovarian cancer correlates with poor prognosis, but the mechanisms that regulate the PD‐L1 expression in OC remain poorly understood. We have recently shown that IFNγ induces the PD‐L1 expression in OC cells, resulting in their increased proliferation and invasion. Here, we show that the IFNγ‐induced PD‐L1 expression in OC cells is associated with increased levels of STAT1, Tyr‐701 pSTAT1 and Ser‐727 pSTAT1 in OC cells. JAK1 and STAT1 suppression significantly decreases the IFNγ‐induced PD‐L1 mRNA and protein levels in OC cells. In addition, IRF1 suppression significantly decreases the IFNγ‐induced gene and protein levels of PD‐L1, indicating that the IFNγ‐induced PD‐L1 expression in OC cells is dependent on IRF1 signaling. Chromatin immunoprecipitation data demonstrate that IFNγ induces occupancy of STAT1, Ser‐727 pSTAT1 and IRF1 at STAT1 and IRF1 binding sites in human PD‐L1 promoter. Together, these results show that the IFNγ‐induced PD‐L1 expression in OC cells is regulated by IRF1/JAK1/STAT1 signaling, and suggest that targeting the IRF1/JAK1/STAT1 pathway may provide leverage to regulate the PD‐L1 levels in ovarian cancer.

Investigating Mechanisms of Subcutaneous Preconditioning Incubation for Neural Stem Cell Embedded Hydrogels.

Stem cells are a vital component of regenerative medicine therapies, however, only a fraction of stem cells delivered to the central nervous system following injury survive the inflammatory environment. Previously, we showed that subcutaneous preconditioning of neural stem cell (NSC) embedded hydrogels for 28 days improved spinal cord injury (SCI) functional outcomes over controls. Here, we investigated the mechanism of subcutaneous preconditioning of NSC-embedded hydrogels, with and without the known neurogenic cue, interferon gamma (IFN-γ), for 3, 14, or 28 days to refine and identify subcutaneous preconditioning conditions by measurement of neurogenic markers and cytokines. Studying the preconditioning mechanism, we found that subcutaneous foreign body response (FBR) associated cytokines infiltrated the scaffold in groups with and without NSCs, with time point effects. A pro-inflammatory environment with upregulated interleukin (IL)-6, IL-10, macrophage inflammatory protein (MIP)-1, MIP-2, IFN-γ-inducible protein 10 (IP-10), tumor necrosis factor-α (TNF-α), and IL-12p70 was observed on day 3. By 14 and 28 days, there was an increase in pro-regenerative cytokines (IL-13, IL-4) along with pro-inflammatory markers IL-1β, IP-10, and RANTES (regulated on activation, normal T cell expressed, and secreted) potentially part of the mechanism that had an increased functional outcome in SCI. Coinciding with changes in cytokines, the macrophage population increased over time from 3 to 28 days, whereas neutrophils peaked at 3 days with a significant decrease at later time points. Expression of the neuronal marker βIII tubulin in differentiating NSCs was supported at 3 days in the presence of soluble and immobilized IFN-γ and at 14 days by immobilized IFN-γ only, but it was greatly attenuated in all conditions at 28 days, partially because of dilution via host cell infiltration. We conclude that subcutaneously incubating NSC seeded scaffolds for 3 or 14 days could act as host specific preconditioning through exposure to FBR while retaining βIII tubulin expression of NSCs to further improve the SCI functional outcome observed with 28 day subcutaneous incubation.

QuantiFERON-TB Gold Plus Assay in Patients With Latent vs. Active Tuberculosis in a Low Incidence Setting: Level of IFN-γ, CD4/CD8 Responses, and Release of IL-2, IP-10, and MIG

ObjectivesWe analyzed the results of the QuantiFERON Glod Plus assay (QFT) and cytokine patterns associated with active tuberculosis (ATB) among patients with positive QFT.MethodsA total of 195 patients are QFT-positive, among which 24 had an ATB and 171 had a latent tuberculosis infection (LTBI). Interferon-gamma (IFN-γ) secretion was analyzed relative to interleukin-2 (IL-2), IFN-γ inducible protein or CXCL-10 (IP-10), and monokine induced by IFN-γ or CXCL-9 (MIG) secretion, and then compared between two sets of peptide antigens [tube 1 - cluster of differentiation 4 (CD4+) T cell stimulation; tube 2 - CD4+/CD8+ T cell response].ResultsHigher IFN-γ responses were measured in the ATB group (p = 0.0089). The results showed that there was a lower ratio of tube 1/tube 2 IFN-γ concentrations in the ATB group (p = 0.0009), and a median [interquartile ranges (IQR)] difference between the two sets at −0.82 IU/ml (−1.67 to 0.18) vs. −0.07 IU/ml (−0.035 to 0.11, p < 0.0001) in the ATB group compared to the LTBI group, respectively. In addition, patients with low ratios of IL-2/IFN-γ, IP-10/IFN-γ, and MIG/IFN-γ were much more likely to have ATB.ConclusionHigh levels of IFN-γ secretion, preferential IFN-γ response in tube 2, and lower secretion of IL-2, IP-10, and MIG release relative to IFN-γ secretion were more likely observed in subjects with ATB. These features of T cell response may be helpful in low prevalence settings to suspect ATB in patients tested positive for IFN-γ release assays (IGRA).