Rheumatoid arthritis (RA) is a systemic inflammatory autoimmune disease that leads to joint destruction and disability. Despite a significant progress in administration of biological agents for RA patients, there is still a need for improved therapy. Intravenous-immunoglobulins (IVIG) , a pooled polyspecific immunoglobulin-G (IgG) extracted from 20,000 healthy subjects, showed beneficial therapeutic effect in patients with immune-deficiency, sepsis, and autoimmune diseases. The current study aim to investigate the beneficial effect of treatment with IVIG in established collagen induced arthritis in DBA/1j mice. Murine arthritis was induced in DBA/1j mice. The treatment with IVIG started when the disease was established. The clinical score was followed twice a week until day 48. The mice were bled for plasma, the paws were H&E stained. Cytokine profile in the plasma was analyzed by Luminex technology, titers of circulating anti-collagen antibodies in the plasma was tested by ELISA. Our results show that treatment with IVIG in murine, significantly rreduced the clinical arthritis score (P<0.001). Moreover, mode of action show that IVIG significantly reduced circulating level of inflammatory cytokines (IFN, IL-1β, IL-17, IL-6, TNFα) (P<0.001), inhibit anti-collagen antibodies (P < 0.001) in the plasma of CIA mice. Importantly, histopathological examination revealed that IVIG treatment prevented the migration of inflammatory immune cells into the cartilage and synovium, reduced the extent of joint damage and preserved joint architecture. Our results proved for the first time the valuable anti-inflammatory treatment of IVIG in experimental RA. We propose IVIG therapy for a subgroup of patients with as rheumatological-related diseases.

Backgroud: A long-term hepatic inflammatory response is a risk factor for liver cancer initiation and progression. Interleukin (IL)-35 is the newest member of the IL-12 cytokine family, and has been reported to play an essential role in the immunosuppressive liver microenvironment. Herein we focus on the expression profiles of IL-35 in hepatocellular carcinoma (HCC) and the effect on local immune status. Methods: HCC transcriptome array data were downloaded from Gene Expression Omnibus. The bioinformatics analysis was performed by the BRB array tools and online Ingenuity Pathway Analysis software. The serum IL-35 level was detected by AimPlet bead-based immunoassay. In situ IL-35 expression detection was performed by immunohistochemical staining and western blot. Results: Our results showed that there were large amounts of IL-35 expressed in HCC serum and tumor tissues. IL-35 expression affects the transcript of thousands of genes, most of which correlated with T-cell immunity. This study proved that enhancement of regulatory T cells (Tregs) and impairment of cytolytic T cells are prominent effects of IL-35. Conclusions: Elevated IL-35 played critical roles in HCC patients through affecting the balance between Tregs and cytotoxic T cells. Dissection of the precise targets and the underlying molecular mechanisms will lead to alternative treatments for HCC patients.

Background. Anti-citrullinated protein/peptide antibodies (ACPA) play important roles in the pathogenesis of rheumatoid arthritis (RA). ACPA-positive (ACPA+) and ACPA-negative (ACPA-) RA were suggested to be different disease subsets with distinct differences in genetic variation and clinical outcomes. The aims of the present study were to compare gene expression profiles in ACPA+ and ACPA- RA and identify novel candidate gene signatures that might serve as therapeutic targets. Methods. Comprehensive transcriptome analysis of peripheral blood mononuclear cells (PBMCs) from ACPA+ and ACPA- RA patients, and healthy controls was performed via RNA sequencing. A validation cohort was used to further investigate differentially expressed genes via PCR and ELISA. Spearman’s correlation test was used to evaluate the correlation of differentially expressed genes and the clinical and laboratory data of the patients. The role of differentially expressed genes in osteoclastogenesis was further investigated. Results. Expression of C-X-C motif chemokine ligand 2 (CXCL2) was significantly increased in ACPA+ RA than in ACPA- RA, which was validated in PBMCs and serum. CXCL2 promoted the migration of CD14+ monocytes and increased osteoclastogenesis in RA patients. RAW264.7 macrophages were used to investigate specific mechanisms, and the results suggested that CXCL2 stimulated osteoclastogenesis via ERK MAPK and NFκB pathways. Conclusion. CXCL2 was highly expressed in ACPA+ RA than in ACPA- RA. CXCL2 promoted osteoclastogenesis and was related to bone erosion in RA, which suggest that the blockade of CXCL2 might be a novel strategy for the treatment of RA.

Innate immune sensing of viral molecular patterns is essential for development of antiviral responses. Like many viruses SARS CoV-2 has evolved strategies to circumvent innate immune detection including low CpG levels in the genome, glycosylation to shield essential elements including the receptor binding domain, RNA shielding and generation of viral proteins that actively impede anti-viral interferon responses. Together these strategies allow widespread infection and increased viral load. Despite the efforts of immune subversion SARS-CoV-2 infection does activate innate immune pathways inducing a robust type I/III interferon response, production of proinflammatory cytokines, and recruitment of neutrophils and myeloid cells. This may induce hyperinflammation or alternatively, effectively recruit adaptive immune responses that help clear the infection and prevent reinfection. The dysregulation of the renin-angiotensin system due to downregulation of angiotensin converting enzyme 2, the receptor for SARS-CoV-2, together with the activation of type I/III interferon response, and inflammasome response converge to promote free radical production and oxidative stress. This exacerbates tissue damage in the respiratory system but also leads to widespread activation of coagulation pathways leading to thrombosis. Here, we review the current knowledge of the role of the innate immune response following SARS-CoV-2 infection, much of which is based on the knowledge from SARS-CoV and other coronaviruses. Understanding how the virus subverts the initial immune response and how an aberrant innate immune response contributes to the respiratory and vascular damage in COVID-19 may help explain factors that contribute to the variety of clinical manifestations and outcome of SARS-CoV-2 infection.

Chronic Granulomatous Disease (CGD) is a rare inherited disorder in which phagocytes lack NADPH oxidase activity. The most common form is the X-linked CGD (X-CGD), caused by mutations in the CYBB gene. Clinical, functional and genetic characterizations of 16 CGD cases of male patients and their relatives were done. We classified them as suffering from different variants of CGD (X910, X91− or X91+) according to NOX2 expression and NADPH oxidase activity in neutrophils. Twelve mutations were novel (10 X910-CGD and 2 X91− -CGD). One X910-CGD was due to a new and extremely rare double missense mutation Thr208Arg-Thr503Ile. We investigated the pathological impact of each single using stable transfection of each mutated cDNA in the NOX2 knock-out PLB-985 cell line. Both mutations leading to X91−-CGD were also novel; one deletion -67delT was localized in the promoter region of CYBB, the second one c.253-1879A>G mutation activates a splicing donor site, which unveils a cryptic acceptor site, leading to the inclusion of a 124-nucleotide pseudo-exon between exons 3 and 4 and responsible for the partial loss of NOX2 expression. Both X91−-CGD mutations were characterized by a low cytochrome b558 expression and a faint NADPH oxidase activity. The functional impact of new missense mutations is discussed in the context of a new 3D-model of the dehydrogenase domain of NOX2. Our study demonstrates that low NADPH oxidase activity found in both X91−-CGD patients correlates with mild clinical forms of CGD whereas X910-CGD and X91+-CGD cases remain the most clinically severe forms.

Immune response variations could define successful resistance to Hepatitis C Virus (HCV) infection. Toll-like receptors (TLR)-3 are innate detectors of dsRNA viruses while bacterial and viral unmethylated CpG motifs are recognized by TLR9. We previously reported that TLR3.rs3775290 “CC” genotype was associated with HCV chronicity, while TLR9 gene played no major role in this infection. This study identified the role of TLR3.rs3775290 (c.1377C/T), TLR9.rs5743836 (-1237T→C) and TLR9.rs352140 (G2848A) gene polymorphisms in predicting the outcome of HCV-specific cell-mediated immunity (CMI) among Egyptian healthcare workers (HCWs) and patients. We enrolled 546 subjects (409 HCWs and 137 patients) divided into four groups. Group1: 265 seronegative, aviraemic subjects; group2: 25 seronegative, viraemic subjects; group3: 87 subjects with spontaneously resolved HCV infection; and group4: 169 chronic HCV HCWs and patients. All subjects were genotyped by PCR-restriction fragment length polymorphism (PCR-RFLP) analysis for the TLR3.rs3775290, TLR9.rs5743836 and TLR9.rs352140 SNPs. We, also, quantified HCV-specific CMI in 265 HCWs distributed among the four groups using an interferon gamma (IFN-γ) enzyme-linked immunospot (ELISpot) assay in response to nine HCV genotype 4a overlapping 15mer peptide pools covering the whole viral genome. No statistically significant difference was found between CMI responding subjects with different HCV states and TLR3.rs3775290 genotype or TLR9.rs352140. However, there was a significant relationship between the outcome of the HCV-specific CMI and the TLR9.rs5743836 genotype among the responding subjects (p=0.005) and the chronic HCV patients (p=0.044). In conclusion, TLR9.rs5743836 SNP; but not TLR3.rs3775290 or TLR9.rs352140 genotypes; could predict the outcome of HCV-specific CMI responses among genotype-4-infected Egyptians.

Growing evidence shows that a homozygous 6.7-kb deletion of the novel anti-inflammatory molecule leukocyte immunoglobulin like receptor A3 (LILRA3) is associated with many autoimmune disorders. However, its effects on pathogenesis of inflammatory bowel disease (IBD) have not been clarified yet. LILRA3 is mainly expressed in monocytes, whereas its effects on biological behaviors of monocytes have not been systematically reported. To investigate the association between LILRA3 polymorphism and IBD susceptibility, LILRA3 polymorphism was assessed in 378 IBD patients and 509 healthy controls in our study, quantitative real-time PCR (qRT-PCR), western blot and immunohistochemistry (IHC) were employed to detect the LILRA3 expression in IBD patient blood and intestinal samples. Despite no association of the polymorphism with IBD development was found, LILRA3 expression was markedly increased in IBD patients compared with healthy controls. Human U937 monocyte cell line was employed to establish LILRA3-overexpressing cells and the effects of LILRA3 on the biological behaviors of U937 cells were systematically explored. We found that overexpression of LILRA3 in monocytes led to significant decreases in secretion of interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6). Additionally, LILRA3 abated monocyte migration by reducing the expression of several chemokines and enhanced monocyte phagocytosis by increasing CD36 expression. Furthermore, LILRA3 promoted monocyte proliferation through a combination of Akt and MEK/Erk signaling pathways. We report for the first time that LILRA3 is related to IBD and functions as an anti-inflammatory modulator in U937 cells.

The interesting report by Karagianni P et al on the finding of increased DNA methylation of H19 locus imprinting control region in saliva samples of Sjögren’s syndrome patients correlating with low complement C4 levels, may offer insights into how C4 level may be regulated in serpinopathies such as C1-inhibitor deficiency. An undetectable or low C4 level in patients with severe angioedema is a feature of C1-inhibitor deficiency (hereditary angioedema (HAE) type I with low to absent function and antigenic levels; HAE type II with point mutations in SERPING1 gene that affect the reactive centre loop affecting protein function only). However, C4 levels do not always clinically correlate with disease activity, and up to 6% patients do not have known mutations in the SERPING1 gene.

Although increasing evidence demonstrates the association between intestinal dysbiosis and pancreatic diseases, such as chronic pancreatitis and pancreatic cancer, it remains largely unknown whether intestinal dysbiosis is involved in the immunopathogenesis of autoimmune pancreatitis (AIP). Recently, we found that intestinal dysbiosis mediates experimental AIP via the activation of plasmacytoid dendritic cells (pDCs), which can produce IFN-α and IL-33. However, candidate pathobionts for type 1 AIP have not been identified. In this study, we tried to identify pathobionts associated with type 1 AIP. Fecal samples were obtained from type 1 AIP patients before and after prednisolone (PSL) treatment and subjected to 16S ribosomal RNA sequencing to evaluate the composition of intestinal bacteria. Induction of remission by PSL was associated with the complete disappearance of Klebsiella species from feces, in two of the three analyzed patients with type 1 AIP. To assess the pathogenicity of Klebsiella species, mild experimental AIP was induced in MRL/MpJ mice by repeated injections of 10 μg of polyinosinic-polycytidylic acid (poly (I:C)) in combination with oral administration of heat-killed Klebsiella pneumoniae. The AIP pathology score was significantly higher in MRL/MpJ mice that received both oral administration of heat-killed K. pneumoniae and intraperitoneal injections of poly (I:C) than in those administered with either agent alone. Pancreatic accumulation of pDCs capable of producing large amounts of IFN-α and IL-33 was also significantly higher in mice that received both treatments. These data suggest that intestinal colonization by K. pneumoniae may play a pathogenic role in AIP.

Background: Bacillus Calmette-Guérin (BCG) vaccination policies of countries are postulated to have effect on the course of coronavirus disease 2019 (COVID-19) pandemic. Methods: Retrospective cross-sectional study was conducted between March 11-June 10, 2020 in a chest clinic in a state hospital in Istanbul,Turkey. Adults with diagnosis of COVID-19 pneumonia confirmed with severe acute respiratory syndrome coronavirus 2 polymerase chain reaction positivity in a nasopharyngeal sample and pulmonary infiltrates in computed chest tomography were included consecutively. Sociodemographic characteristics, body-mass index, smoking status, comorbid diseases, income rates, and BCG-vaccination status were compared between severe and mild patients with COVID-19 pneumonia. Results: Study population consisted of 123 adults (mean age, 49.7 years [standard deviation, 13.3 years]; 82 (66.7%) male). The proportion of BCG-vaccinated cases was significantly lower among severe patients than mild patients with COVID-19 pneumonia (68.5% vs 88.2%; p=.026). Mean age (54.0 ± 11.5 years vs 38.3 ±10.7 years; p <.001), diabetes rate (32.6% vs 5.9%; p=.002) and low-income (84.3% vs 52.9% p<.001) are higher in patients with severe COVID-19 pneumonia than in patients with mild COVID-19 pneumonia. Multivariate logistic regression analysis showed that increasing age (odds ratio [OR], 1.112; 95% confidence interval [CI], 1.058 – 1.169; p<.001) and low income (OR, 3.369; 95% CI, 1.074 – 10.570; p =.037) are associated with severe COVID-19 pneumonia. Conclusion: Clinical data does not support that being vaccinated with BCG is associated with disease severity in COVID-19 pneumonia. Age and low-income are the major predictors for disease severity.

The aim of this multicenter retrospective study was to evaluate the incidence of hyperprogressive disease after treatment with pembrolizumab as a second-line treatment in patients (n=167) with non-small-cell lung cancer (NSCLC) with metastatic disease whose tumors expressed programmed death-ligand-1 in ≥1% and to search for factors associated with its development. All patients received platinum-containing chemotherapy as a first-line treatment. The neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), and their derivations were retrospectively analyzed. The psoas major muscle area (PMMA) was calculated at the L3 position on computed tomography before chemotherapy and immunotherapy. Patients with ∆PMMA≥10% were considered to have sarcopenia (low muscle mass). We also performed multinomial logistic regression to estimate the effects of hematological biomarkers and ∆PMMA on the response to immunotherapy. Hyperprogressors (HPs) had significantly higher NLRs, PLRs and ∆PMMA levels than the other patients. Moreover, in multivariate regression analysis, higher levels of ∆PMMA were associated with a decreased likelihood of being a progressor (P) (OR, 0.81; 95% CI, 0.65-0.99; p=0.047) or a nonprogressor (NP) (OR, 0.76; 95% CI, 0.62-0.94; p=0.012) vs an HP. In multivariate analysis, higher NLRs tended to decrease the likelihood of being a P vs an HP (OR, 0.66; 95% CI, 0.42-1.06; p=0.09) and significantly decrease the likelihood of being an NP vs an HP (OR, 0.44; 95% CI, 0.28-0.69; p<0.0001). Our data suggest that a high pre-immunotherapy NLR and the presence of sarcopenia are potential risk factors for the development of hyperprogressive disease.

Peroxiredoxins (PRXs) are intracellular antioxidative enzymes but work as inflammatory amplifiers under the extracellular condition. To date, the function of PRXs in the pathogenesis of multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) is not fully understood. The aim of this study was to investigate whether PRXs play a role in the pathogenesis of MS and NMOSD. We analyzed levels of PRXs (PRX1, PRX5, and PRX6) in the CSF and serum of 16 patients with MS, 16 patients with NMOSD, and 15 patients with other neurological disorders (ONDs). We identified potential correlations between significantly elevated PRXs levels and the clinical variables in patients with MS and NMOSD. Additionally, pathological analyses of PRXs (PRX1-6) in the central nervous system were performed using the experimental autoimmune encephalomyelitis (EAE), animal model of MS. We found that serum levels of PRX5 and PRX6 in patients with MS and NMOSD were higher compared with those in patients with ONDs (p < 0.05). Furthermore, high levels of PRX5 and PRX6 were partly associated with blood–brain barrier dysfunction and disease duration in NMOSD patients. No significant elevation was found in CSF PRXs levels of MS and NMOSD. Spinal cords from EAE mice showed remarkable PRX5 staining, especially in CD45+ infiltrating cells. In conclusion, PRX5 and PRX6 may play a role in the pathogeneses of MS and NMOSD.

Background NOD-like receptor pyrin 7 (NLRP7) has been identified as the major gene responsible for the recurrent hydatidiform mole (RHM). The immunological role of NLRP7 mutation in HM patients has not been conclusively demonstrated. Hence, we aim to demonstrate this role in our study. Methods We followed 12 new patients with NLRP7 nonsynonymous variations (NSVs) from date to date. Peripheral blood mononuclear cells (PBMCs) were collected from patients with and without NLRP7 mutation, separately. Supernatant IL-1β secretion, intracellular pro-IL-1β and mature-IL-1β expressions were measured after 24h lipopolysaccharide (LPS) stimulation. Plasmids with corresponding NSVs were generated to evaluate the ability of processing pro-IL-1β into mature-IL-1β in vitro. Results Homozygous or compound heterozygous NLRP7 mutation secreted less IL-1β in root of abnormal intracellular pro-IL-1β or mature-IL-1β according to different domain defective. Plasmids with NSVs could also affect processing or/and trafficking together with caspase-1 and apoptosis-associated speck-like protein (ASC). Conclusion Inflammasome related NLRP7 mutation is a potential mechanism of RHM.

Background: Cladribine (CdA), an oral prodrug approved for the treatment of relapsing multiple sclerosis, selectively depletes lymphocytes. CdA passes the blood-brain barrier suggesting a potential effect on CNS resident cells. Objective: We examined, if CdA modifies the phenotype and function of naïve and activated primary mouse microglia, when applied in different concentrations including 0.1-1 µM that putatively overlaps human CSF concentrations. Methods: Primary microglia cultures without stimulation or in the presence of proinflammatory lipopolysaccharide (LPS) or anti-inflammatory IL-4 were co-treated with different concentrations of CdA for 24 hours. Viability was assessed by MTT assay. Phagocytotic ability and morphology were examined by flow cytometry, and random migration by IncuCyte Zoom and TrackMate. Change in gene expression was examined by qPCR, and protein secretion by Meso Scale Discovery. Results: LPS and IL-4 upregulated deoxycytidine kinase (DCK) expression. Only activated microglia were affected by CdA, and this was unrelated to viability. CdA 0.1-1 µM significantly reduced granularity, phagocytotic ability and random migration of activated microglia. CdA 10 µM increased the IL-4-induced gene expression of Arg1 and LPS-induced expression of IL-1beta, TNF, iNOS, and Arg1, but protein secretion remained unaffected. CdA 10 µM potentiated the increased expression of anti-inflammatory TNFR2 but not TNFR1 induced by LPS. Conclusion: Microglia acquire a less activated phenotype when treated with 0.1–1 µM CdA that putatively overlaps human CSF concentrations. This may be related to the upregulated gene expression of DCK upon activation and suggests a potential alternative mechanism of CdA with direct effect on CNS resident cells.

Though the pathogenesis of acute myeloid leukemia (AML) is still unknown, accumulating evidence has revealed that immune response plays a vital part in the pathogenesis. Here, we investigated the involvement of 24 single-nucleotide polymorphisms (SNPs) of immuno-related genes, including cytokines (IL2, IL4, IL9, IL-12A, IL-22, IFNG, and TGFB1), transcriptional regulatory genes (TBX21, STAT1, STAT3, STAT5B, STAT6, GATA3, FOXP3, and IRF4), and others (IL2RA IL6R NFKBIA), in 269 AML inpatients and 200 healthy controls. Furthermore, we analyzed the relationship between the SNPs and clinical characteristics. Immuno-related SNP genotyping was performed on the Sequenom MassARRAY iPLEX platform. All the SNPs in healthy controls were consistent with Hardy–Weinberg equilibrium. All final p values were adjusted by Bonferroni multiple testing. Our results showed that IL-22 (rs2227491) was significantly associated with the white blood cell (WBC) counts. STAT5B (rs6503691) showed a close relationship with the recurrent genetic abnormalities in patients with AML. We verified the negatively independent effect of age and risk of cytogenetics on overall survival (OS). More importantly, the GG genotype of IL-12A (rs6887695) showed a negative impact on AML prognosis independently. Furthermore, the relative expression of IL-12 was decreased in GG genotype, no matter under codominant or recessive model. However, no correlation was observed between the SNPs mentioned above and disease susceptibility, risk stratification, and survival. Our findings suggest that immuno-related gene polymorphisms are associated with prognosis in AML, which may perform as novel inspection targets for AML patients.

Properdin is the only one positive regulator of the complement system. In this study, we characterize the prevalence, functional consequences and disease associations of autoantibodies against properdin in a cohort of patients with autoimmune disease systemic lupus erythematosus (SLE), suffering from lupus nephritis (LN). We detected autoantibodies against properdin in plasma of 22.5% of the LN patients (16/71) by ELISA. The binding of these autoantibodies to properdin was dose-dependent and was validated by surface plasmon resonance. Higher levels of anti-properdin were related to high levels of anti-dsDNA and ANA and to low concentrations of C3 and C4 in patients and also with histological signs of LN activity and chronicity. The high negative predictive value (NPV) of anti-properdin and anti-dsDNA combination suggested that patients who are both negative for anti-properdin and anti-dsDNA will not have severe nephritis. IgG from anti- properdin positive patients’ plasma increased the C3b deposition on late apoptotic cells by flow cytometry. Nevertheless, these IgGs did not modify substantially the binding of properdin to C3b, the C3 convertase C3bBb and the pro-convertase C3bB, evaluated by surface plasmon resonance. In conclusion, anti- properdin autoantibodies exist in LN patients. They have weak but relevant functional consequences, which could have pathological significance.

Background: Pulmonary sarcoidosis is characterized by an exaggerated CD4+ T-cell response and formation of non-necrotizing granulomas. Tumour necrosis factor α (TNF-α) is regarded as crucial for granuloma formation and TNF-α inhibitors offer a 3rd line treatment option for patients not responding to conventional treatment. However, not all patients benefit from treatment, and an optimal dose and treatment duration have not been established. Insight into the influence of TNF-α inhibitors on lung immune cells may provide clues to what drives inflammation in sarcoidosis and improve our understanding of treatment outcomes. Objectives: To evaluate effects of treatment with the TNF- α inhibitor infliximab on lung immune cells and clinical features of the patients. Methods: Thirteen patients with sarcoidosis refractory to conventional treatment were assessed with bronchoalveolar lavage (BAL), spirometry and CT scan in close adjacent to start of infliximab treatment. These investigations were repeated after six months of treatment. Results: Treatment with TNF- α inhibitor infliximab was well tolerated with no adverse events, except for one patient who developed a probable adverse event with liver toxicity. Ten patients were classified as responders, having a reduced CD4/CD8 ratio, a decreased percentage of CD4+ T-cells expressing the activation marker CD69 and number of mast cells (p<0.05 for all). The percentage of T regulatory cells (Tregs), defined as FoxP3+ CD4+ T-cells decreased in most patients. Conclusions: Six months of infliximab treatment in patients with sarcoidosis led to signs of decreased CD4+ T-cell alveolitis and decreased mastocytosis in the lungs of responders.