Serum Levels of 54 Cytokines and Chemokines Reveal Distinct Inflammatory Signatures in Ankylosing Spondylitis

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the third virus that caused coronavirus-related outbreaks over the past 20 years. The outbreak was first reported in December 2019 in Wuhan, China, but rapidly progressed into a pandemic of an unprecedented scale since the 1918 flu pandemic. Besides respiratory complications in patients with COVID-19, clinical characterization of severe infection cases showed several other comorbidities, including multiple organ failure, and septic shock. To better understand the systemic pathogenesis of COVID-19, we interrogated the virus's presence in the peripheral blood cells, which might provide a form of trafficking or hiding to the virus. By analyzing >2 billion sequence reads of high-throughput transcriptome sequence data from 180 samples of patients with active SARS-CoV-2 infection or healthy controls collected from 6 studies, we found evidence of traces of SARS-CoV-2 RNA in peripheral blood mononuclear cells in two samples from two independent studies. In contrast, the viral RNA was abundant in bronchoalveolar lavage specimens from the same patients. We also devised a “viral spike-to-actin” RNA normalization as a metric to compare across various samples and minimize errors caused by intersample variability in total human RNA abundance. Our observation suggests immune presentation and discounts the possibility of extensive viral infection of lymphocytes or monocytes.

Peripheral Blood Mononuclear Cells of Mycetoma Patients React Differently to Madurella mycetomatis Antigens than Healthy Endemic Controls

IntroductionIn rheumatoid arthritis (RA) immune activation and presence of autoantibodies may precede clinical onset of disease, and joint destruction can progress despite remission. However, the underlying temporal changes of such immune system abnormalities in the inflammatory response during treat-to-target strategies remain poorly understood. We have previously reported low levels of the soluble form of CD18 (sCD18) in plasma from patients with chronic RA and spondyloarthritis. Here, we study the changes of sCD18 before and during treatment of early RA and following arthritis induction in murine models of rheumatoid arthritis.MethodsThe level of sCD18 was analyzed with a time-resolved immunoflourometric assay in 1) plasma from early treatment naïve RA patients during a treat-to-target strategy (the OPERA cohort), 2) plasma from chronic RA patients, 3) serum from SKG and CIA mice following arthritis induction, and 4) supernatants from synovial fluid mononuclear cells (SFMCs) and peripheral blood mononuclear cells (PBMCs) from 6 RA patients cultured with TNFα or adalimumab.ResultsPlasma levels of sCD18 were decreased in chronic RA patients compared with early RA patients and in early RA patients compared with healthy controls. After 12 months of treatment the levels in early RA patients were similar to healthy controls. This normalization of plasma sCD18 levels was more pronounced in patients with very early disease who achieved an early ACR response. Plasma sCD18 levels were associated with radiographic progression. Correspondingly, the serum level of sCD18 was decreased in SKG mice 6 weeks after arthritis induction compared with healthy littermates. The sCD18 levels in both SKG and CIA mice exhibited a biphasic course after arthritis induction with an initial increase above baseline followed by a decline. Shedding of CD18 from RA SFMC and RA PBMC cultures was increased by TNFα and decreased by adalimumab.ConclusionsThe plasma sCD18 levels were altered in patients with RA, in mice with autoimmune arthritis and in cell cultures treated with TNFα and adalimumab. Decreased levels of plasma sCD18 could reflect autoimmunity in transition from early to chronic disease and normalization in response to treatment could reflect autoimmunity in remission.

Immune Activation in Patients With Irritable Bowel Syndrome

Considering the phenotypic and serological heterogeneity of systemic lupus erythematosus (SLE) and rheumatoid arthritis(RA), significant challenges may intervene with the precise diagnosis. In this regard, numerous studies have shown that changes in DNA methylation levels can be used to distinguish between healthy individuals and those with SLE and RA, as well as to predict disease activity and prognosis. In the current study, we evaluated quantitative methylation level of CDKN2A promoter in peripheral blood mononuclear cells (PBMCs) of SLE and RA patients, and healthy controls by methylation-quantification of endonuclease-resistant DNA (MethyQESD), a bisulfite conversion-independent method. Our findings revealed an excessive hypomethylation of CDKN2A in SLE and RA patients compared to healthy individuals (P < 0.001). Besides, by determining efficient cutoff value, the specificity of CDKN2A for correct diagnosis of healthy subjects was measured to be 77.30% and the sensitivity for SLE and RA diagnosis were 81.33%, and 72%, respectively. Furthermore, CDKN2A methylation level was shown to be positively associated with C3 and C4 levels and negatively associated with anti‑dsDNA concentration (P < 0.001). Moreover, a statistically significant difference in the DNA methylation levels of CDKN2A promoter was identified between SLE cases with age of ≤ 18 and patients with > 18 years of age (P = 0.025). Our findings demonstrated that CDKN2A methylation levels in PBMCs of SLE and RA patients could be used as a promising diagnostic biomarker. The significant association between hypomethylation of CDKN2A promoter and disease activity factors in SLE patients, is suggesting that CDKN2A hypomethylation could be used as an alternative biomarker for assessment of disease activity. Key Points • Several studies have reported increased expression of CDKN2A in SLE and RA suggesting that it may be involved in the pathogenesis of these disorders. • CDKN2A hypomethylation has been implicated in different autoimmune diseases. • Our findings demonstrated that CDKN2A methylation levels in PBMCs of SLE and RA patients could be used as a promising diagnostic and prognostic biomarker.

BackgroundType 1 diabetes (T1DM) is associated with premature cardiovascular disease (CVD) and a pro-inflammatory state whilst the proangiogenic miR-126-3p/-5p may play a role in CVD. Animal studies established miR-126 to be pro-angiogenic. We hypothesised miR-126-3p/-5p are reduced in T1DM whilst pro-inflammatory cytokines are increased.Methods29 well controlled, T1DM patients without CVD and 20 healthy controls (HCs) were studied. MiR-126-3p/-5p were assayed in plasma and peripheral blood mononuclear cells (PBMCs) whilst Chemokine C-X-C Receptor 1/2 (CXCR1/2) mRNA in PBMCs by real-time quantitative PCR. Cytokines were assayed by the Mesoscale Discovery. Ingenuity Pathway Analysis (IPA) was used to predict target genes, cellular functions and pathological states regulated by miR-126-3p/-5p. IPA generated both direct and indirect causations between different targets and analysed whether these effects would be inhibitory or stimulatory based on the published evidence.ResultsT1DM patients had a relatively good diabetic control (HbA1c = 7.4 ± 0.7% or 57.3 ± 7.6 mmol/mol). Homeostatic cytokine IL-7, pro-inflammatory cytokines IL-8 and TNF-α, and vascular endothelial growth factor-C (VEGF-C) were increased in T1DM, versus HCs; p = 0.008, p = 0.003, p = 0.041 and p = 0.013 respectively. MiR-126-5p was significantly upregulated in PBMCs in T1DM versus HCs; p = 0.01, but not in plasma. MiR-126-3p was unchanged. CXCR1/2 were elevated in T1DM versus HCs; p = 0.009 and p < 0.001 respectively. MiR-126-5p was positively correlated with CXCR1/2, and with HbA1c whilst negatively correlated with circulating endothelial progenitor cells (CD34+CD133+CD45dim) and fibronectin adhesion assay in a combined group of T1DM patients and HCs; p = 0.028 p = 0.049 p = 0.035 p = 0.047 and p = 0.004 respectively. IPA predicted miR-126-5p to be anti-inflammatory through the inhibition of chemokine C–C motif ligand 27, chymotrypsin-like elastase 2A and IL-7, whilst miR-126-3p had no direct anti-inflammatory effect. Simultaneously IPA predicted IL-7 as the most upstream cytokine target.ConclusionsT1DM without apparent CVD or diabetic complications is an inflammatory state characterised not only by raised pro-inflammatory cytokines but also by increased receptor CXCR1/2 and miR-126-5p. MiR-126-5p upregulation may represent a compensatory response. Pro-miR-126-5p therapies or anti-IL-7 therapies may be a new option to reduce both inflammation and CVD risk in T1DM. Further research is required in a large prospective study in patients with T1DM.

Background The present study focused on the potential clinical significance of miR-3934 in the occurrence and development of asthma. Methods 80 asthma and 80 healthy controls were recruited in this study. The peripheral blood mononuclear cells (PBMCs) and serum samples of the asthma patients as well as the healthy controls were isolated, and the expression levels of miR-3934 in PBMCs were examined by RT-qPCR methods. Furthermore, the relationship between the level of miR-3934 in PBMCs and the disease severity has been analyzed, and the potential diagnostic value of miR-3934 was evaluated by the receiver operating characteristics (ROC) curve. Finally, the expression level of IL-6, IL-8, and IL-33 have been detected using the ELISA kits, and Pearson's correlation analysis was performed to investigate the relationship between the level of miR-3934 in PBMCs and the serum expression of those inflammatory cytokines in asthma patients. Results miR-3934 was dramatically decreased in PBMCs of the asthma patients, and miR-3934 was markedly reduced in PBMCs of patients with severe asthma vs. mild asthma. Furthermore, ROC analysis showed that levels of miR-3934 in PBMCs can distinguish asthma patient, especially the severe asthma patients from the controls. Finally, the levels of miR-3934 in PBMCs were negatively correlated with the serum levels of IL-6, IL-8, and IL-33 in asthma patients, respectively. Conclusions miR-3934 was downregulated in PBMCs of asthmatic patients and may function as a potential diagnosis biomarker.

Characterization of Epstein-Barr virus–infected B cells in patients with posttransplantation lymphoproliferative disease: disappearance after rituximab therapy does not predict clinical response

Characterization of Epstein-Barr virus–infected B cells in patients with posttransplantation lymphoproliferative disease: disappearance after rituximab therapy does not predict clinical response

BackgroundRheumatoid arthritis (RA) is a chronic autoimmune disease, which commonly affects women. Accumulating evidence shows that differentially expressed circular RNAs (circRNAs) play crucial roles in the progress of RA. However, the roles of circRNAs in female RA remains unclear. This study explores potential role and diagnostic value of hsa_circ_0140271 from peripheral blood mononuclear cells (PBMC) in female RA.MethodsDifferential expression of circRNAs was determined by RNA-sequencing in PBMC from 4 healthy controls (HC) and 4 RA patients, and we further measured the level of hsa_circ_0140271 in a validation cohort consisting of 47 RA and 47 HC via RT-qPCR. Besides, correlation studies with clinical variables were also examined. What’s more, we performed bioinformatics analysis to predict the potential role of hsa_circ_0140271.ResultsPBMC expression of hsa_circ_0140271 of female RA was significantly higher than that of female HC, and it was positively correlated with antistreptolysin (ASO). Furthermore, the receiver operating characteristic (ROC) curve indicated that hsa_circ_0140271 could distinguish female RA from female HC and female patients with ankylosing spondylitis (AS) or osteoarthritis (OA). Besides, the combined diagnosis anti-cyclic citrullinated peptide (Anti-CCP) + hsa_circ_0140271 could improve diagnostic accuracy with an area under the curve (AUC) of 0.818 to compared with Anti-CCP. Furthermore, KEGG pathway enrichment analysis indicated hsa_circ_0140271 may act as microRNA sponge and participate in fatty acid metabolism pathways.ConclusionHsa_circ_0140271 was likely to be used as a promising diagnostic biomarker for female RA; it may act as microRNA sponge to regulate fatty acid metabolism pathways in RA.

Objectives. Ankylosing spondylitis (AS) is a chronic inflammatory disease characterized by new bone formation. Recent evidence suggests that new bone formation in AS may be due to upregulation of Wnt signaling in the osteoblastic pathway secondary to low serum Dickkopf homolog 1 (Dkk-1) levels. And miR-29a orchestrates osteoblast differentiation through direct targeting and negative regulation of Dkk-1.Methods. We initially validated the expression levels of miR-29a in the peripheral blood mononuclear cells (PBMCs) of AS patients (n = 30), rheumatoid arthritis (RA) patients (n = 30) and healthy controls (n = 30) using real-time quantitative reverse transcription PCR (qRT-PCR). Correlation analysis was assessed between miR-29a level in PBMCs of AS patients and disease activity indexes, including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), Bath ankylosing spondylitis disease activity index (BASDAI), Bath ankylosing spondylitis function index (BASFI) and modified Stoke ankylosing spondylitis spinal score (mSASSS).Results. Significantly higher expression of miR-29a was observed in PBMCs of AS patients (Ct 9.18 ± 1.96) compared with that in RA patients (10.97 ± 0.70, p < 0.001) and healthy controls (Ct 11.45 ± 1.23, p < 0.001). There was no significant difference between RA patients and healthy controls in miR-29a expression (p > 0.05). Elevated miR-29a expression is not correlated with disease activity index (p > 0.05). A weak correlation was found between elevated miR-29a expression and mSASSS (r = −0.393, p = 0.032).Conclusions. We report for the first time elevated miR-29a expression in PBMCs of patients with ankylosing spondylitis, and miR-29a might be used as a useful diagnostic marker in new bone formation but cannot reflect disease activity.

OBJECTIVES: Ankylosing spondylitis (AS) is a chronic inflammatory disease characterized by new bone formation. Recent evidence suggests that new bone formation in AS may be due to upregulation of Wnt signaling in the osteoblastic pathway secondary to low serum Dickkopf homolog 1 (Dkk-1) levels. And miR-29a orchestrates osteoblast differentiation through direct targeting and negative regulation of Dkk-1. METHODS: We initially validated the expression levels of miR-29a in the peripheral blood mononuclear cells (PBMCs) of AS patients (n=30), rheumatoid arthritis (RA) patients (n=30) and healthy controls (n=30) using real-time quantitative reverse transcription PCR (qRT-PCR). Correlation analysis was assessed between miR-29a level in PBMCs of AS patients and disease activity indexes, including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), Bath ankylosing spondylitis disease activity index (BASDAI), Bath ankylosing spondylitis function index (BASFI) and modified Stoke ankylosing spondylitis spinal score (mSASSS). RESULTS: Significantly higher expression of miR-29a was observed in PBMCs of AS patients (Ct 9.18±1.96) compared with that in RA patients (10.97±0.70, p<0.001) and healthy controls (Ct 11.45±1.23, p<0.001). There was no significant difference between RA patients and healthy controls in miR-29a expression (p>0.05). Elevated miR-29a expression is not correlated with disease activity index (p>0.05). A weak correlation was found between elevated miR-29a expression and mSASSS (r=-0.393, p=0.032). CONCLUSIONS: We report for the first time elevated miR-29a expression in PBMCs of patients with ankylosing spondylitis, and miR-29a might be used as a useful diagnostic marker in new bone formation but cannot reflect disease activity.

Novel PBMC LncRNA signatures as diagnostic biomarkers for colorectal cancer

Emerging evidence indicate that long noncoding RNAs (lncRNAs) may play an important role in the pathogenesis of systemic lupus erythematosus (SLE) however, the contribution of lncRNAs to SLE remains largely unclear. Our study aimed to explore the lncRNA expression profiles in peripheral blood mononuclear cells (PBMCs) from SLE patients. LncRNA sequencing was used to detect differentially expressed genes in PBMCs from 5 SLE-MIX samples and 3 healthy controls (HC)-MIX samples, and the expression of selected lncRNAs was further verified by real-time quantitative polymerase chain reaction (RT‒qPCR). The correlation of lncRNA expression with laboratory indicators as well the SLE disease activity index 2000 (SLEDAI‒2K) score from 72 SLE patients was assessed by Spearman's test. The association between lncRNA ENST00000597482 and organ involvement in SLE patients was determined by the Mann‒Whitney U test. Moreover, lymphocyte subsets in peripheral blood from SLE patients were measured by flow cytometry. In addition, the diagnostic value of lncRNAs in predicting SLE was evaluated by receiver operating characteristic (ROC) curve analysis. The lncRNA expression profiles demonstrated 218 differentially expressed lncRNAs, including 121 upregulated genes and 97 downregulated genes, in PBMCs from SLE patients compared to HCs. Among the 10 candidate genes selected, only lncRNA ENST00000597482, which was lower in SLE PBMCs than in HCs, was consistent with the sequencing results. LncRNA ENST00000597482 expression was negatively correlated with SLEDAI-2K score and the titres of ANA antibodies and anti-double-stranded DNA (anti-dsDNA) antibodies. Of note, SLE patients with lower expression of lncRNA ENST00000597482 were prone to develop organ involvement. Furthermore, lncRNA ENST00000597482 exhibited potential diagnostic value in differentiating SLE patients from HCs. LncRNA ENST00000597482 expression was lower in PBMCs from SLE patients than HCs and was negatively correlated with the SLEDAI-2K score and autoantibody titres. In addition, lncRNA ENST00000597482 could act as a novel biomarker for disease activity and diagnosis of SLE.

BackgroundHuntington’s disease (HD) is an autosomal dominant neurodegenerative condition caused by an expanded CAG repeat in the gene encoding huntingtin (HTT). Optimizing peripheral quantification of huntingtin throughout the course of HD is valuable not only to illuminate the natural history and pathogenesis of disease, but also to detect peripheral effects of drugs in clinical trial.RationaleWe previously demonstrated that mutant HTT (mHTT) was significantly elevated in purified HD patient leukocytes compared with controls and that these levels track disease progression. Our present study investigates whether the same result can be achieved with a simpler and more scalable collection technique that is more suitable for clinical trials.MethodsWe collected whole blood at 133 patient visits in two sample sets and generated peripheral blood mononuclear cells (PBMCs). Levels of mHTT, as well as N-, and C-terminal and mid-region huntingtin were measured in the PBMCs using ELISA-based Meso Scale Discovery (MSD) electrochemiluminescence immunoassay platforms, and we evaluated the relationship between different HTT species, disease stage, and brain atrophy on magnetic resonance imaging.ConclusionsThe assays were sensitive and accurate. We confirm our previous findings that mHTT increases with advancing disease stage in patient PBMCs, this time using a simple collection protocol and scalable assay.