Serum amyloid-A in Behçet’s disease

The association between Behçet disease activity and elevated systemic immune-inflammation index: A retrospective observational study in a tertiary care hospital

Background The systemic immune-inflammation index (SII) is a novel marker for predicting the prognosis in patients with various diseases and cancers. We aimed to investigate the relationship between SII and disease activity in patients with Behçet disease (BD). Methods Our retrospective study included 513 patients with BD aged ≥18 years. The patients were classified into an active group (n=355) and an inactive group (n=158). Pearson correlation analysis was performed to elucidate correlations between the SII and other markers. Binary logistic regression analysis was used to determine BD-related risk factors. Receiver operating characteristic (ROC) curves were computed to assess cut-offs for the predictive value of the SII and other markers. Results Patients with active BD had a significantly higher SII (p<0.001) than those in the inactive group. ROC analysis revealed that the optimal SII cut-off value to identify BD activity was 526.23, with 70.4% sensitivity and 70.3% specificity. Pearson correlation coefficient (r) demonstrated a significant positive correlation between SII, and the C-reactive protein level (r=0.427, p<0.001), erythrocyte sedimentation rate (r=0.422, p<0.001), platelet- lymphocyte ratio (r=0.711, p<0.001), and neutrophil- lymphocyte ratio (r=0.672, p<0.001). According to binary logistic regression analysis, the SII (odds ratio [OR] 1.003; 95% confidence interval [CI] 1.001-1.004; p=0.002) was an independent risk factor for active BD. Conclusion The SII can be considered a novel predictor of BD activity.

Tuning Monocytes and Macrophages for Personalized Therapy and Diagnostic Challenge in Rheumatoid Arthritis

Monocytes/macrophages play a central role in chronic inflammatory disorders, including rheumatoid arthritis (RA). Activation of these cells results in the production of various mediators responsible for inflammation and RA pathogenesis. On the other hand, the depletion of macrophages using specific antibodies or chemical agents can prevent their synovial tissue infiltration and subsequently attenuates inflammation. Their plasticity is a major feature that helps the switch from a pro-inflammatory phenotype (M1) to an anti-inflammatory state (M2). Therefore, understanding the precise strategy targeting pro-inflammatory monocytes/macrophages should be a powerful way of inhibiting chronic inflammation and bone erosion. In this review, we demonstrate potential consequences of different epigenetic regulations on inflammatory cytokines production by monocytes. In addition, we present unique profiles of monocytes/macrophages contributing to identification of new biomarkers of disease activity or predicting treatment response in RA. We also outline novel approaches of tuning monocytes/macrophages by biologic drugs, small molecules or by other therapeutic modalities to reduce arthritis. Finally, the importance of cellular heterogeneity of monocytes/macrophages is highlighted by single-cell technologies, which leads to the design of cell-specific therapeutic protocols for personalized medicine in RA in the future.

Serum Amyloid A in Inflammatory Rheumatic Diseases: A Compendious Review of a Renowned Biomarker

Serum amyloid A (SAA) is an acute phase protein with a significant importance for patients with inflammatory rheumatic diseases (IRD). The central role of SAA in pathogenesis of IRD has been confirmed by recent discoveries, including its involvement in the activation of the inflammasome cascade and recruitment of interleukin 17 producing T helper cells. Clinical utility of SAA in IRD was originally evaluated nearly half a century ago. From the first findings, it was clear that SAA could be used for evaluating disease severity and monitoring disease activity in patients with rheumatoid arthritis and secondary amyloidosis. However, cost-effective and more easily applicable markers, such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), overwhelmed its use in clinical practice. In the light of emerging evidences, SAA has been discerned as a more sensitive biomarker in a wide spectrum of IRD, especially in case of subclinical inflammation. Furthermore, a growing number of studies are confirming the advantages of SAA over many other biomarkers in predicting and monitoring response to biological immunotherapy in IRD patients. Arising scientific discoveries regarding the role of SAA, as well as delineating SAA and its isoforms as the most sensitive biomarkers in various IRD by recently developing proteomic techniques are encouraging the revival of its clinical use. Finally, the most recent findings have shown that SAA is a biomarker of severe Coronavirus disease 2019 (COVID-19). The aim of this review is to discuss the SAA-involving immune system network with emphasis on mechanisms relevant for IRD, as well as usefulness of SAA as a biomarker in various IRD. Therefore, over a hundred original papers were collected through an extensive PubMed and Scopus databases search. These recently arising insights will hopefully lead to a better management of IRD patients and might even inspire the development of new therapeutic strategies with SAA as a target.

Serum Amyloid A Is a Biomarker of Disease Activity and Health-Related Quality-of-Life in Patients with Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

Serum amyloid A (SAA) is one of the acute phase proteins synthesized in hepatocytes and secreted by various inflammation or infectious stimuli. We investigated the clinical implication of measuring SAA in patients with antineutrophil cytoplasmic antibody- (ANCA-) associated vasculitis (AAV). Seventy-five patients who had been classified as AAV and enrolled in our prospective observational cohort for AAV patients were included. Clinical and laboratory data were obtained on the day of blood sampling, and SAA was measured by ELISA kits. Birmingham Vasculitis Activity Score (BVAS) and Short-Form 36-Item Health Survey (SF-36) were assessed for disease activity and health-related quality-of-life (HRQoL) measures. We stratified patients into having high BVAS when the BVAS was over the median values, and those with either low SF-36 PCS or low SF-36 MCS were defined as having poor HRQoL. Multivariate logistic regression analysis was conducted to estimate independent predictors of high BVAS. The relative risk (RR) was analyzed using the contingency tables and the chi-squared test. SAA was positively correlated with BVAS (r = 0.642) and FFS (r = 0.367) and was inversely correlated with both the SF-36 physical component summary (r = -0.456) and mental component summary scores (r = -0.394). Furthermore, SAA was significantly correlated with acute phase reactants ESR (r = 0.611) and CRP (r = 0.629). Patients with high BVAS exhibited significantly higher SAA than those with low BVAS (1317.1 ng/mL vs. 423.1 ng/mL). In multivariable logistic regression analysis, serum albumin (odds ratio (OR) 0.132) and SAA > 1173.6 ng/mL (OR 15.132) were independently associated with high BVAS. The risk of having high BVAS and poor HRQoL in patients with SAA > 1173.6 ng/mL was higher than in those with SAA ≤ 1173.6 ng/mL (RR 3.419 and 1.493). Our results suggest that SAA might be a useful biomarker in assessing disease activity and HRQoL in AAV.

Serum amyloid A binds to fibrin(ogen), promoting fibrin amyloid formation

Complex associations exist between inflammation and thrombosis, with the inflammatory state tending to promote coagulation. Fibrinogen, an acute phase protein, has been shown to interact with the amyloidogenic ß-amyloid protein of Alzheimer’s disease. However, little is known about the association between fibrinogen and serum amyloid A (SAA), a highly fibrillogenic protein that is one of the most dramatically changing acute phase reactants in the circulation. To study the role of SAA in coagulation and thrombosis, in vitro experiments were performed where purified human SAA, in concentrations resembling a modest acute phase response, was added to platelet-poor plasma (PPP) and whole blood (WB), as well as purified and fluorescently labelled fibrinogen. Results from thromboelastography (TEG) suggest that SAA causes atypical coagulation with a fibrin(ogen)-mediated increase in coagulation, but a decreased platelet/fibrin(ogen) interaction. In WB scanning electron microscopy analysis, SAA mediated red blood cell (RBC) agglutination, platelet activation and clumping, but not platelet spreading. Following clot formation in PPP, the presence of SAA increased amyloid formation of fibrin(ogen) as determined both with auto-fluorescence and with fluorogenic amyloid markers, under confocal microcopy. SAA also binds to fibrinogen, as determined with a fluorescent-labelled SAA antibody and correlative light electron microscopy (CLEM). The data presented here indicate that SAA can affect coagulation by inducing amyloid formation in fibrin(ogen), as well as by propelling platelets to a more prothrombotic state. The discovery of these multiple and complex effects of SAA on coagulation invite further mechanistic analyses.

Critical regulation of Th17 cell differentiation by serum amyloid-A signalling in Behcet's disease

The current understandings on cellular and molecular biology suggest that Th17 axis plays a pivotal role in Behcet's disease (BD) pathogenesis. Recently the role of serum amyloid-A (SAA) as a potential marker of disease activity in BD patients has been explored, and it has been reported that the occurrence of specific clinical features are significantly associated with high serum levels of this inflammatory mediator. The aim of this study was to investigate the cytokine-like activity of SAA in inducing Th17 differentiation from CD4 + T naive cells in BD. Purified peripheral monocytes from BD and healthy control (HC) were stimulated with SAA "in vitro", and secreted IL-8, TNF-α, IL-18, IFN-α, IFN-γ, IL-1β and IL-6 were measured using a Bio-Rad multiplex cytokine immunoassay. To assess Th17 differentiation, purified CD4 + T cells were challenged with anti-CD3/CD28 antibodies, while cultured with supernatant derived from SAA stimulated monocytes, and intracellular staining of IL-17A and IFN-γ was evaluated by flow-cytometry. Furthermore, peripheral blood mononuclear cells (PBMCs) were stimulated with SAA and transcript levels of RAR-related orphan nuclear receptor (ROR)-γt and IL-17A were assessed by Real-time PCR. Upon stimulation with SAA, monocytes obtained from both HC and BD groups released large amounts of IL-8, IL-6, TNF-α, IL-1β and IFN-α. Monocytes-derived supernatants from BD patients, but not HC, were capable of promoting Th17 but not Th1 differentiation from CD4 + T cells. However, SAA did not induce up-regulation of Th17 specific mRNA transcript such as IL-17A and (ROR)-γt in PBMCs from both HC and BD. In BD patients SAA induced Th17 polarization rather than Th1 differentiation from CD4 + T cells. These data suggest that a critical regulation of Th17 may be the functional link between acute SAA increase and the induction of Th17 mediated inflammatory response in BD.

No effects without causes: the Iron Dysregulation and Dormant Microbes hypothesis for chronic, inflammatory diseases

Since the successful conquest of many acute, communicable (infectious) diseases through the use of vaccines and antibiotics, the currently most prevalent diseases are chronic and progressive in nature, and are all accompanied by inflammation. These diseases include neurodegenerative (e.g. Alzheimer's, Parkinson's), vascular (e.g. atherosclerosis, pre-eclampsia, type 2 diabetes) and autoimmune (e.g. rheumatoid arthritis and multiple sclerosis) diseases that may appear to have little in common. In fact they all share significant features, in particular chronic inflammation and its attendant inflammatory cytokines. Such effects do not happen without underlying and initially 'external' causes, and it is of interest to seek these causes. Taking a systems approach, we argue that these causes include (i) stress-induced iron dysregulation, and (ii) its ability to awaken dormant, non-replicating microbes with which the host has become infected. Other external causes may be dietary. Such microbes are capable of shedding small, but functionally significant amounts of highly inflammagenic molecules such as lipopolysaccharide and lipoteichoic acid. Sequelae include significant coagulopathies, not least the recently discovered amyloidogenic clotting of blood, leading to cell death and the release of further inflammagens. The extensive evidence discussed here implies, as was found with ulcers, that almost all chronic, infectious diseases do in fact harbour a microbial component. What differs is simply the microbes and the anatomical location from and at which they exert damage. This analysis offers novel avenues for diagnosis and treatment.

MicroRNA155 Expression in Relation to BDCAF Scored Behçet's Disease in an Egyptian Patients' Sample

Objective:

To discover the possibility of using microRNA155 (miRNA155) expression level as a biomarker of Behçet's Disease (BD) activity or remission.

Methods:

Thirty BD patients’ white blood cells (WBCs) miRNA155 expression was measured and compared to WBCs miRNA155 expression in 15 healthy subjects. Assessment of disease activity was done using Behçet's Disease Current Activity Form (BDCAF).

Results:

miRNA155 expression significantly decreases with the increase of BD activity scored by BDCAF.

Conclusion:

Increased miRNA155 may be used as a biomarker of BD remission and thus in the disease follow up. There could be a prospect of treating the disease via microRNA 155 effect enhancement.

Serum amyloid A as a marker of disease activity and treatment response in Takayasu arteritis

Assessment of disease activity in Takayasu arteritis (TA) is challenging. We aimed to study utility of serum amyloid A (SAA) to assess disease activity and its association with SAA gene polymorphisms, if any, in our TA patients. Serum of 99 consecutive adult TA patients and 40 healthy controls were assayed for SAA. Depending on the ITAS2010 and ITAS-CRP score, patients were designated as having active disease if ITAS2010 ≥ 2 or ITAS-CRP ≥ 3 and stable disease if ITAS2010 = 0 or ITAS-CRP is ≤1. Clinical ITAS of 0 with raised inflammatory markers scoring a ITAS-CRP of 2 was considered as indeterminate for disease activity assessment. Repeat SAA levels for active group was measured after 6 months from baseline. SAA levels between active and stable disease as well as serial levels were compared. DNA of 40 patients and controls were genotyped for SAA polymorphisms (rs12218, rs2468844) and the allele frequencies were compared. At baseline, SAA levels were higher in patients as compared to controls (137.4 vs 100.8 ng/ml, p = 0.001) and higher in patients with active disease (166.4 ng/ml) than those with stable disease (98.2 ng/ml), p = 0.001. SAA decreased during follow-up in treatment responders (189.9 ng/ml at baseline vs 119.0 ng/ml at follow-up, p = 0.008); in contrast, there was no significant change among non-responders during follow-up. Allelic frequencies of SAA gene polymorphisms did not differ between cases and controls. SAA may be a reliable biomarker to assess disease activity and treatment response in TA.

Association between some inflammatory markers and primary ovarian insufficiency

OBJECTIVE

This study investigated the discriminative values of neutrophil-to-lymphocyte ratio (NLR), serum amyloid A protein (SAA), and C-reactive protein (CRP) in cases of primary ovarian insufficiency (POI).

METHODS

A total of 84 women were included in this comparative cross-sectional study. The study group consisted of 43 women diagnosed as having POI, and the control group consisted of 41 women with normal fertility. After obtaining a written informed consent form from all participants, we retrieved clinical and demographic data and laboratory findings from the participants and the hospital database. The following variables were analyzed: age, body mass index, smoking, family history, comorbidities, sonographic findings, complete blood count, baseline hormone levels, CRP, and SAA.

RESULTS

NLR was significantly lower in the study group than in the control group (mean [SD], 1.3 [0.7] vs 2.0 [0.7]; P < 0.001). The mean SAA level was 151.6 ng/mL (range, 48.5-12,554.7 ng/mL) in the study group and 147.8 ng/mL (range, 29.8-3,760.4 ng/mL) in the control group (P > 0.05). There was no significant difference in serum CRP levels between two groups (P > 0.05). Receiver operating characteristic analysis revealed that NLR, but not SAA and CRP, was a significantly discriminative parameter for POI (area under the curve, 0.829; P < 0.001). Multivariate logistic regression analysis showed that a family history of POI, smoking, and NLR of 1.5 or less were independent risk factors for POI.

CONCLUSIONS

SAA and CRP do not seem to be valuable discriminative markers for POI, whereas NLR may be a significant promising marker before presentation or in the early stages of POI and may be useful for developing appropriate fertility treatment options.

Immunometabolic biomarkers of inflammation in Behçet's disease: relationship with epidemiological profile, disease activity and therapeutic regimens

Behcet's disease (BD) is a systemic inflammatory disease with a still unclear pathogenesis. Although several inflammatory molecules have been studied, current biomarkers are largely insensitive in BD and unable to predict disease progression and response to treatment. Our primary aim was to explore serum levels of soluble CD40 L (sCD40L), soluble intracellular adhesion molecule (sICAM-1), monocyte chemoattractant protein-1 (MCP-1), myeloperoxidase (MPO), leptin, resistin, osteoprotegerin (OPG), soluble type 1 tumour necrosis factor receptor (sTNFR), interleukin (IL)-6 and serum amyloid A (SAA) serum concentration in a cohort of 27 BD patients. The secondary aim was to evaluate potential correlations between the putative circulating biomarkers, demographic profile of patients, the status of disease activity, the specific organ involvement at the time of sample collection and different therapeutic regimens. Serum concentrations of sTNFR (P = 0·008), leptin (P = 0·0011), sCD40L (P < 0·0001) and IL-6 (P = 0·0154) were significantly higher in BD patients than in HC, while no difference was found in MCP-1, MPO and resistin serum levels. Moreover, we observed significantly higher sTNFR serum concentrations in BD patients presenting inactive disease than HC (P = 0·0108). A correlation between sTNFR and age was also found, with higher levels in patients over 40 years than HC (P = 0·0329). Although further research is warranted to elucidate the role of circulating biomarkers, some of that may contribute to the understanding of the physiopathology processes underlying BD activity and damage as well as to provide useful tools for prognostic purposes and a personalized treatment approach.

Putative Role of Serum Amyloid-A and Proinflammatory Cytokines as Biomarkers for Behcet's Disease

Behcet's disease (BD) is a multisystemic disorder of unknown etiology characterized by relapsing oral-genital ulcers, uveitis, and involvement of vascular, gastrointestinal, neurological, and musculoskeletal system. Although disease pathogenesis is still unclear, both innate and adaptive immunity have shown to play a pivotal role, and multiple proinflammatory cytokines seem to be involved in different pathogenic pathways that eventually lead to tissue damage.The aims of our study were to evaluate serum cytokines levels of IL-8, IL-18, IFN-α2a, IL-6, IFN-γ, CXCL10, CXCL11, CXCL9, and SAA levels in patients with BD, in comparison to healthy controls (HC), and to correlate their levels to disease activity.We included 78 serum samples obtained from 58 BD patients and analyzed a set of proinflammatory cytokines including IL-8, IL-18, IFN-α2a, IL-6, IFN-γ, CXCL10, CXCL11, and CXCL9 by multiplex bead analysis as well as SAA by enzyme-linked immunosorbent assay.Compared to HC, BD patients showed elevated cytokine levels of IL-8, IL-18, IFN-α2a, and IL-6, and low levels of CXCL11. BD patients with SAA serum levels >20 mg/L showed higher levels of proinflammatory markers than HC or group with SAA ≤20 mg/L. IL-18, IFN-α2a, and IL-6 were higher in BD group with SAA >20 mg/L than HC, while IL-8 and CXCL9 levels were higher than in patients with SAA ≤20 mg/L and HC.Active BD patients with SAA >20 mg/L exhibited elevated levels of inflammatory mediators, suggesting that may exist a relationship between SAA and proinflammatory cytokines in the intricate scenario of BD pathogenesis.

Development of de novo major involvement during follow-up in Behçet's syndrome

The primary aim of the study was to evaluate the incidence of de novo major involvement during follow-up in a cohort of patients with Behçet's syndrome (BS); the secondary aim was to analyse the epidemiological profile and the long-term outcome of those patients who developed new major involvement. Among our cohort of 120 BS patients, we evaluated all subjects who had no major organ involvement during the early years of their disease; specifically, at disease onset, the 52% of the cohort presented a prevalent mucocutaneous involvement. The primary outcomes were represented by the following: Hatemi et al. (Rheum Dis Clin North Am 39(2):245-61, 2013) the incidence of de novo major involvement during the follow-up and Hatemi et al. (Clin Exp Rheumatol 32(4 Suppl 84):S112-22, 2014) the use of immunosuppressive drugs during the follow-up. We have defined the development of de novo major involvement during the follow-up as the occurrence of severe ocular, vascular or CNS involvement after a latency period from the diagnosis of at least 3 years. Among 62 patients characterized by a mild onset of disease, we observed that after at least 3 years from the diagnosis, 21 BS patients (34%) still developed serious morbidities. Specifically, three patients developed ocular involvement, nine patients developed neurological involvement and nine patients presented vascular involvement. Comparing main epidemiological and clinical findings of the two groups, we observed that patients who developed de novo major involvement were more frequently males and younger; furthermore, 95% of these patients were characterized by a young onset of disease (p < 0.001). Being free of major organ complication in the first years of BS is not necessary a sign of a favourable outcome. Globally, the development of de novo major involvement during the coursfce of BS suggests that a tight control is strongly recommended during the course of the disease.