Expression and function of serum amyloid A, a major acute-phase protein, in normal and disease states

The effect of feed supplementation with Transcarpathian zeolite (clinoptilolite) on the concentrations of acute phase proteins and cytokines in the serum and hepatic tissue of chickens

The aim of the this study was to determine the effect of different levels of Transcarpathian zeolite (clinoptilolite) on selected indicators of the immune response in chickens by assessing the concentrations of the acute phase proteins haptoglobin, C-reactive protein (CRP), serum amyloid A, transferrin, and alpha-1-acid glycoprotein and the cytokines tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), IL-2, and IL-10 in the serum and hepatic tissues of chickens. The study was conducted on 450 one-day-old male Ross 308 chickens. The total rearing period was 42 D. The samples of blood and liver were collected before the start of the study (day 0) and on day 42, after rearing was completed. ELISA kits specific for chicken CRP, haptoglobin, alpha-1-acid glycoprotein, serum amyloid A, transferrin, TNF-α, IFN-γ, IL-2, and IL-10 were used to determine the levels of acute phase proteins and cytokines in the serum and liver homogenates. The results of immunological tests suggest that for long-term maintenance of homeostasis in chickens, the addition of 2% zeolite as a feed additive is most beneficial. The results indicate that 3% clinoptilolite induce production of Th1 pro-inflammatory cytokines, increasing the synthesis of IL-2, IFN-γ, and TNF-α. The high concentration of IL-10 after the use of zeolite in conjunction with the high concentration of IL-2, TNF-α, and IFN-γ indicates a reduction in the intensity of inflammatory processes, the enhancement of the humoral immune response, and the simultaneous inhibition of the production of Th1-type cytokines. The increase of CRP concentration in conjunction with high concentrations of pro- and anti-inflammatory cytokines in the birds from the group receiving 3% clinoptilolite demonstrates indicates that it can influence the development of local inflammatory processes and enhance immune regulation in birds. Our research has shown that clinoptilolite influences on an increase in birds' resistance to infection, as confirmed by clinical observations and anatomopathological examination and by the increase in the synthesis of acute phase proteins with immunoregulatory properties.

Applications and strategies in nanodiagnosis and nanotherapy in lung cancer

Lung cancer is the second most common cancer and the leading cause of death in both men and women in the world. Lung cancer is heterogeneous in nature and diagnosis is often at an advanced stage as it develops silently in the lung and is frequently associated with high mortality rates. Despite the advances made in understanding the biology of lung cancer, progress in early diagnosis, cancer therapy modalities and considering the mechanisms of drug resistance, the prognosis and outcome still remains low for many patients. Nanotechnology is one of the fastest growing areas of research that can solve many biological problems such as cancer. A growing number of therapies based on using nanoparticles (NPs) have successfully entered the clinic to treat pain, cancer, and infectious diseases. Recent progress in nanotechnology has been encouraging and directed to developing novel nanoparticles that can be one step ahead of the cancer reducing the possibility of multi-drug resistance. Nanomedicine using NPs is continuingly impacting cancer diagnosis and treatment. Chemotherapy is often associated with limited targeting to the tumor, side effects and low solubility that leads to insufficient drug reaching the tumor. Overcoming these drawbacks of chemotherapy by equipping NPs with theranostic capability which is leading to the development of novel strategies. This review provides a synopsis of current progress in theranostic applications for lung cancer diagnosis and therapy using NPs including liposome, polymeric NPs, quantum dots, gold NPs, dendrimers, carbon nanotubes and magnetic NPs.

Alterations in Peripheral Organs following Combined Hypoxemia and Hemorrhagic Shock in a Rat Model of Penetrating Ballistic-Like Brain Injury

Polytrauma, with combined traumatic brain injury (TBI) and systemic damage are common among military and civilians. However, the pathophysiology of peripheral organs following polytrauma is poorly understood. Using a rat model of TBI combined with hypoxemia and hemorrhagic shock, we studied the status of peripheral redox systems, liver glycogen content, creatinine clearance, and systemic inflammation. Male Sprague-Dawley rats were subjected to hypoxemia and hemorrhagic shock insults (HH), penetrating ballistic-like brain injury (PBBI) alone, or PBBI followed by hypoxemia and hemorrhagic shock (PHH). Sham rats received craniotomy only. Biofluids and liver, kidney, and heart tissues were collected at 1 day, 2 days, 7 days, 14 days, and 28 days post-injury (DPI). Creatinine levels were measured in both serum and urine. Glutathione levels, glycogen content, and superoxide dismutase (SOD) and cytochrome C oxidase enzyme activities were quantified in the peripheral organs. Acute inflammation marker serum amyloid A-1 (SAA-1) level was quantified using western blot analysis. Urine to serum creatinine ratio in PHH group was significantly elevated on 7-28 DPI. Polytrauma induced a delayed disruption of the hepatic GSH/GSSG ratio, which resolved within 2 weeks post-injury. A modest decrease in kidney SOD activity was observed at 2 weeks after polytrauma. However, neither PBBI alone nor polytrauma changed the mitochondrial cytochrome C oxidase activity. Hepatic glycogen levels were reduced acutely following polytrauma. Acute inflammation marker SAA-1 showed a significant increase at early time-points following both systemic and brain injury. Overall, our findings demonstrate temporal cytological/tissue level damage to the peripheral organs due to combined PBBI and systemic injury.

Influence of short peptides with aromatic amino acid residues on aggregation properties of serum amyloid A and its fragments

Serum amyloid A variant 1.1 (SAA1.1) is an acute phase protein. In response to injury, inflammation or infection its production increases highly, which may lead to aggregation of the protein and accumulation of its deposits in various organs. Due to the cellular toxicity of the aggregates, as well as the fact that accumulated deposits are a burden that obstructs proper functioning of the affected tissues, it is vital to find a way to suppress the process of pathological aggregates formation. To make this possible, it is necessary to investigate thoroughly the oligomerization process and recognize factors that may influence its course. Some previous studies showed that aromatic interactions are important to the potential of an inhibitor to suppress the aggregation process. In our research we had proved that a five-residue peptide RSFFS (saa1-5) is an efficient inhibitor of aggregation of the most amyloidogenic fragment of SAA1.1, SAA1-12. In the present work the oligomerization and aggregation propensity of SAA1-12 was compared to that of SAA1-27, in order to determine the contribution of the sequence which extends beyond the most amyloidogenic region but encompasses residues reportedly involved in the stabilization of the SAA native conformation. Thioflavin T fluorescence assay, quantitative chromatographic analysis of the insoluble fraction and transmission electron microscopy allowed for a deeper insight into the SAA aggregation process and the morphology of aggregates. Substitutions of Phe3 and/or Phe4 residues in saa1-5 sequence with tryptophan, tyrosine, homophenylalanine, naphthylalanine and β,β-diphenylalanine allowed to study the influence of different aromatic systems on the aggregation of SAA1-12 and SAA1-27, and evaluate these results in relation to hSAA1.1 protein. Our results indicate that compounds with aromatic moieties can affect the course of the aggregation process and change the ratio between the soluble and insoluble aggregates.

Tissue-Specific Macrophage Responses to Remote Injury Impact the Outcome of Subsequent Local Immune Challenge

Myocardial infarction, stroke, and sepsis trigger systemic inflammation and organism-wide complications that are difficult to manage. Here, we examined the contribution of macrophages residing in vital organs to the systemic response after these injuries. We generated a comprehensive catalog of changes in macrophage number, origin, and gene expression in the heart, brain, liver, kidney, and lung of mice with myocardial infarction, stroke, or sepsis. Predominantly fueled by heightened local proliferation, tissue macrophage numbers increased systemically. Macrophages in the same organ responded similarly to different injuries by altering expression of tissue-specific gene sets. Preceding myocardial infarction improved survival of subsequent pneumonia due to enhanced bacterial clearance, which was caused by IFNɣ priming of alveolar macrophages. Conversely, EGF receptor signaling in macrophages exacerbated inflammatory lung injury. Our data suggest that local injury activates macrophages in remote organs and that targeting macrophages could improve resilience against systemic complications following myocardial infarction, stroke, and sepsis.

Serum amyloid A: A potential biomarker of lung disorders

Serum amyloid A is an acute-phase protein with multiple immunological functions. Serum amyloid A is involved in lipid metabolism, inflammatory reactions, granuloma formation, and cancerogenesis. Additionally, serum amyloid A is involved in the pathogenesis of different autoimmune lung diseases. The levels of serum amyloid A has been evaluated in biological fluids of patients with different lung diseases, including autoimmune disorders, chronic obstructive pulmonary diseases, obstructive sleep apnea syndrome, sarcoidosis, asthma, lung cancer, and other lung disorders, such as idiopathic pulmonary fibrosis, tuberculosis, radiation pneumonitis, and cystic fibrosis. This review focuses on the cellular and molecular interactions of serum amyloid A in different lung diseases and suggests this acute-phase protein as a prognostic marker.

Inflammation and TGF-β Signaling Differ between Abdominal Aneurysms and Occlusive Disease

Abdominal aortic aneurysms (AAA), are usually asymptomatic until rupture causes fatal bleeding, posing a major vascular health problem. AAAs are associated with advanced age, male gender, and cardiovascular risk factors (e.g. hypertension and smoking). Strikingly, AAA and AOD (arterial occlusive disease) patients have a similar atherosclerotic burden, yet develop either arterial dilatation or occlusion, respectively. The molecular mechanisms underlying this diversion are yet unknown. As this knowledge could improve AAA treatment strategies, we aimed to identify genes and signaling pathways involved. We compared RNA expression profiles of abdominal aortic AAA and AOD patient samples. Based on differential gene expression profiles, we selected a gene set that could serve as blood biomarker or as pharmacological intervention target for AAA. In this AAA gene list we identified previously AAA-associated genes COL11A1, ADIPOQ, and LPL, thus validating our approach as well as novel genes; CXCL13, SLC7A5, FDC-SP not previously linked to aneurysmal disease. Pathway analysis revealed overrepresentation of significantly altered immune-related pathways between AAA and AOD. Additionally, we found bone morphogenetic protein (BMP) signaling inhibition simultaneous with activation of transforming growth factor β (TGF-β) signaling associated with AAA. Concluding our gene expression profiling approach identifies novel genes and an interplay between BMP and TGF-β signaling regulation specifically for AAA.

Evidence for the important role of inflammation in xenotransplantation

There is increasing evidence of a sustained state of systemic inflammation after pig-to-nonhuman primate (NHP) xenotransplantation (that has been termed systemic inflammation in xenograft recipients [SIXR]). Increases in inflammatory markers, e.g., C-reactive protein, histones, serum amyloid A, D-dimer, cytokines, chemokines, and a decrease in free triiodothyronine, have been demonstrated in the recipient NHPs. The complex interactions between inflammation, coagulation, and the immune response are well-recognized, but the role of inflammation in xenograft recipients is not fully understood. The evidence suggests that inflammation can promote the activation of coagulation and the adaptive immune response, but the exact mechanisms remain uncertain. If prolonged xenograft survival is to be achieved, anti-inflammatory strategies (e.g., the administration of anti-inflammatory agents, and/or the generation of genetically-engineered organ-source pigs that are protected from the effect of inflammation) may be necessary to prevent, control, or negate the effect of the systemic inflammation that develops in xenograft recipients. This may allow for a reduction in the intensity of exogenous immunosuppressive therapy. If immunological tolerance to a xenograft is to be obtained, then control of inflammation may be essential.

Anti-inflammatory mechanism of ginsenoside Rg1: Proteomic analysis of milk from goats with mastitis induced with lipopolysaccharide

Previous investigation showed that intravenous injection of ginsenoside Rg1 had a therapeutic effect on Escherichia coli lipopolysaccharide-induced mastitis in lactating goats and it protected animals from lipopolysaccharide challenge via toll-like receptor 4 signaling pathway. The present study was to use proteomic approach to explore the anti-inflammatory mechanisms of Rg1. Nine dairy goats were randomly divided into three groups with 3 animals in each: groups 1 and 2 received intra-mammary infusion of lipopolysaccharide and then intravenously injected with saline or Rg1 solution; animals in group 3 were first intramammarily and then intravenously administered saline solution, and served as a control group. Milk whey at 6 h post lipopolysaccharide challenge was prepared for tandem mass tags based quantitative proteomic analysis. The results showed that 791 proteins were totally identified from the whey. Of them, 98 proteins between groups 1 (lipopolysaccharide + Saline) and 3 (Saline + Saline), and 34 proteins between groups 2 (lipopolysaccharide + Rg1) and 1 were significantly different. Group 1 than group 3 had significantly more inflammatory factors such as interleukin 6, acute phase proteins, blood coagulation factors, complement proteins, and oxidative stress markers while these factors were reduced in group 2 treated with Rg1. In addition, proteins in group 2 associated with peroxisome-proliferator-activated receptor γ activation and recovery of milk fat and production were upregulated compared to group 1. Therefore, Rg1 may exert its anti-inflammatory effect on lipopolysaccharide-induced mastitis in goats via modulating expression of proteins relating to peroxisome-proliferator-activated receptor γ and toll-like receptor 4 signaling pathway.

Serum amyloid A levels are associated with polymorphic variants in the serum amyloid A 1 and 2 genes

BACKGROUND

Serum amyloid A (SAA) is secreted by liver hepatocytes in response to increased inflammation whereupon it associates with high-density lipoprotein (HDL) and alters the protein and lipid composition of HDL negating some of its anti-atherogenic properties.

AIMS

To identify variants within the SAA gene that may be associated with SAA levels and/or cardiovascular disease (CVD).

METHODS

We identified exonic variants within the SAA genes by deoxyribonucleic acid (DNA) Sanger sequencing. We tested the association between SAA variants and serum SAA levels in 246 individuals with and without CVD.

RESULTS

Increased SAA was associated with rs2468844 (beta [β] = 1.73; confidence intervals [CI], 1.14-1.75; p = 0.01), rs1136747 (β = 1.53 (CI, 1.11-1.73); p = 0.01) and rs149926073 (β = 3.37 (CI, 1.70-4.00); p = 0.02), while rs1136745 was significantly associated with decreased SAA levels (β = 0.70 (CI, 0.53-0.94); p = 0.02). Homozygous individuals with the SAA1.3 haplotype had significantly lower levels of SAA compared with those with SAA1.1 or SAA1.5 (β = 0.43 (CI, 0.22-0.85); p = 0.02) while SAA1.3/1.5 heterozygotes had significantly higher SAA levels compared with those homozygous for SAA1.1 (β = 2.58 (CI, 1.19-5.57); p = 0.02).

CONCLUSIONS

We have identified novel genetic variants in the SAA genes associated with SAA levels, a biomarker of inflammation and chronic disease. The utility of SAA as a biomarker for inflammation and chronic disease may be influenced by underlying genetic variation in baseline levels.

Serum Amyloid A Stimulates Vascular and Renal Dysfunction in Apolipoprotein E-Deficient Mice Fed a Normal Chow Diet

Elevated serum amyloid A (SAA) levels may promote endothelial dysfunction, which is linked to cardiovascular and renal pathologies. We investigated the effect of SAA on vascular and renal function in apolipoprotein E-deficient (ApoE^−/−) mice. Male ApoE^−/− mice received vehicle (control), low-level lipopolysaccharide (LPS), or recombinant human SAA by i.p. injection every third day for 2 weeks. Heart, aorta and kidney were harvested between 3 days and 18 weeks after treatment. SAA administration increased vascular cell adhesion molecule (VCAM)-1 expression and circulating monocyte chemotactic protein (MCP)-1 and decreased aortic cyclic guanosine monophosphate (cGMP), consistent with SAA inhibiting nitric oxide bioactivity. In addition, binding of labeled leukocytes to excised aorta increased as monitored using an ex vivo leukocyte adhesion assay. Renal injury was evident 4 weeks after commencement of SAA treatment, manifesting as increased plasma urea, urinary protein, oxidized lipids, urinary kidney injury molecule (KIM)-1 and multiple cytokines and chemokines in kidney tissue, relative to controls. Phosphorylation of nuclear-factor-kappa-beta (NFκB-p-P65), tissue factor (TF), and macrophage recruitment increased in kidneys from ApoE^−/− mice 4 weeks after SAA treatment, confirming that SAA elicited a pro-inflammatory and pro-thrombotic phenotype. These data indicate that SAA impairs endothelial and renal function in ApoE^−/− mice in the absence of a high-fat diet.

Intestinal Serum amyloid A suppresses systemic neutrophil activation and bactericidal activity in response to microbiota colonization

The intestinal microbiota influences the development and function of myeloid lineages such as neutrophils, but the underlying molecular mechanisms are unresolved. Using gnotobiotic zebrafish, we identified the immune effector Serum amyloid A (Saa) as one of the most highly induced transcripts in digestive tissues following microbiota colonization. Saa is a conserved secreted protein produced in the intestine and liver with described effects on neutrophils in vitro, however its in vivo functions remain poorly defined. We engineered saa mutant zebrafish to test requirements for Saa on innate immunity in vivo. Zebrafish mutant for saa displayed impaired neutrophil responses to wounding but augmented clearance of pathogenic bacteria. At baseline, saa mutants exhibited moderate neutrophilia and altered neutrophil tissue distribution. Molecular and functional analyses of isolated neutrophils revealed that Saa suppresses expression of pro-inflammatory markers and bactericidal activity. Saa's effects on neutrophils depended on microbiota colonization, suggesting this protein mediates the microbiota's effects on host innate immunity. To test tissue-specific roles of Saa on neutrophil function, we over-expressed saa in the intestine or liver and found that sufficient to partially complement neutrophil phenotypes observed in saa mutants. These results indicate Saa produced by the intestine in response to microbiota serves as a systemic signal to neutrophils to restrict aberrant activation, decreasing inflammatory tone and bacterial killing potential while simultaneously enhancing their ability to migrate to wounds.

Hepatocytes direct the formation of a pro-metastatic niche in the liver

The liver is the most common site of metastatic disease1. Although this metastatic tropism may reflect the mechanical trapping of circulating tumour cells, liver metastasis is also dependent, at least in part, on the formation of a 'pro-metastatic' niche that supports the spread of tumour cells to the liver2,3. The mechanisms that direct the formation of this niche are poorly understood. Here we show that hepatocytes coordinate myeloid cell accumulation and fibrosis within the liver and, in doing so, increase the susceptibility of the liver to metastatic seeding and outgrowth. During early pancreatic tumorigenesis in mice, hepatocytes show activation of signal transducer and activator of transcription 3 (STAT3) signalling and increased production of serum amyloid A1 and A2 (referred to collectively as SAA). Overexpression of SAA by hepatocytes also occurs in patients with pancreatic and colorectal cancers that have metastasized to the liver, and many patients with locally advanced and metastatic disease show increases in circulating SAA. Activation of STAT3 in hepatocytes and the subsequent production of SAA depend on the release of interleukin 6 (IL-6) into the circulation by non-malignant cells. Genetic ablation or blockade of components of IL-6-STAT3-SAA signalling prevents the establishment of a pro-metastatic niche and inhibits liver metastasis. Our data identify an intercellular network underpinned by hepatocytes that forms the basis of a pro-metastatic niche in the liver, and identify new therapeutic targets.

Involvement of serum amyloid A1 in the rupture of fetal membranes through induction of collagen I degradation

The de novo synthesis of serum amyloid A1 (SAA1) is augmented in human fetal membranes at parturition. However, its role in parturition remains largely unknown. Here, we investigated whether SAA1 was involved in the rupture of fetal membranes, a crucial event in parturition accompanied with extensive degradation of collagens. Results showed that SAA1 decreased both intracellular and extracellular COL1A1 and COL1A2 abundance, the two subunits of collagen I, without affecting their mRNA levels in human amnion fibroblasts. These reductions were completely blocked only with inhibition of both matrix metalloproteases (MMPs) and autophagy. Consistently, SAA1 increased MMP-2/9 abundance and the markers for autophagic activation including autophagy related (ATG) 7 (ATG7) and the microtubule-associated protein light chain 3 β (LC3B) II/I ratio with the formation of LC3 punctas and autophagic vacuoles in the fibroblasts. Moreover, the autophagic degradation of COL1A1/COL1A2 and activation of MMP-2/9 by SAA1 were blocked by inhibitors for the toll-like receptors 2/4 (TLR2/4) or NF-κB. Finally, reciprocal corresponding changes of SAA1 and collagen I were observed in the amnion following spontaneous rupture of membranes (ROM) at parturition. Conclusively, SAA1 may participate in membrane rupture at parturition by degradating collagen I via both autophagic and MMP pathways. These effects of SAA1 appear to be mediated by the TLR2/4 receptors and the NF-κB pathway.

Serum Amyloid Alpha Is Downregulated in Peripheral Tissues of Parkinson's Disease Patients

We report the changed levels of serum amyloid alpha, an immunologically active protein, in Parkinson’s disease (PD) patients’ peripheral tissues. We have previously shown that Saa-1 and -2 (serum amyloid alpha-1,-2, genes) were among the top downregulated genes in PD patients’ skin, using whole-genome RNA sequencing. In the current study, we characterized the gene and protein expression profiles of skin and blood samples from patients with confirmed PD diagnosis and age/sex matched controls. qRT-PCR analysis of PD skin demonstrated downregulation of Saa-1 and -2 genes in PD patients. However, the lowered amount of protein could not be visualized using immunohistochemistry, due to low quantity of SAA (Serum Amyloid Alpha, protein) in skin. Saa-1 and -2 expression levels in whole blood were below detection threshold based on RNA sequencing, however significantly lowered protein levels of SAA1/2 in PD patients’ serum were shown with ELISA, implying that SAA is secreted into the blood. These results show that SAA is differentially expressed in the peripheral tissues of PD patients.

Serum amyloid A predisposes inflammatory tumor microenvironment in triple negative breast cancer

Acute-phase proteins (APPs) are associated with a variety of disorders such as infection, inflammatory diseases, and cancers. The signature profile of APPs in breast cancer (BC) is poorly understood. Here, we identified serum amyloid A (SAA) for proinflammatory predisposition in BC through the signature profiles of APPs, interleukin (IL) and tumor necrosis factor (TNF) superfamily using publicly available datasets of tumor samples and cell lines. Triple-negative breast cancer (TNBC) subtype highly expressed SAA1/2 compared to HER2, luminal A (LA) and luminal B (LB) subtypes. IL1A, IL1B, IL8/CXCL8, IL32 and IL27RA in IL superfamily and CD70, TNFSF9 and TNFRSF21 in TNF superfamily were highly expressed in TNBC compared to other subtypes. SAA is restrictedly regulated by nuclear factor (NF)-κB and IL-1β, an NF-κB activator highly expressed in TNBC, increased the promoter activity of SAA1 in human TNBC MDA-MB231 cells. Interestingly, two κB-sites contained in SAA1 promoter were involved, and the proximal region (-96/-87) was more critical than the distal site (-288/-279) in regulating IL-1β-induced SAA1. Among the SAA receptors, TLR1 and TLR2 were highly expressed in TNBC. Cu-CPT22, TLR1/2 antagonist, abrogated IL-1β-induced SAA1 promoter activity. In addition, SAA1 induced IL8/CXCL8 promoter activity, which was partially reduced by Cu-CPT22. Notably, SAA1/2, TLR2 and IL8/CXCL8 were associated with a poor overall survival in mesenchymal-like TNBC. Taken together, IL-1-induced SAA via NF-κB-mediated signaling could potentiate an inflammatory burden, leading to cancer progression and high mortality in TNBC patients.

Effect of Zinc Sulfate and Zinc Glycine Chelate on Concentrations of Acute Phase Proteins in Chicken Serum and Liver Tissue

The aim of the study was to determine how inorganic and organic forms of zinc affect the concentrations of C-reactive protein (CRP), serum amyloid A (SAA), alpha-1-acid glycoprotein (α-1-AGP), haptoglobin (Hp), and transferrin (TRF) in the blood and liver tissue of 450 1-day-old Ross 308 chicken. Four experimental groups received one the following: inorganic zinc (ZnSO4), a zinc phytase enzyme supplement (ZnSO4-F), organic zinc in combination with glycine (Zn-Gly), or organic zinc supplemented with phytase (Zn-Gly-F). The chicken serum and liver homogenates were assayed using an ELISA kit. The results of the study showed statistically significantly higher serum and liver concentration of SAA in the group of birds that received zinc sulfate in comparison to the group of birds receiving zinc in organic form. A statistically significantly higher serum concentration of CRP and α-1-AGP was also noted in the group receiving zinc sulfate as compared to the Zn-Gly group. Comparison of the serum concentration of TRF between the supplemented groups showed a statistically significant increase in this parameter in the Zn-Gly-F group as compared to the ZSO4-F group. The increase in the serum concentration of Hp in all groups in comparison to the control may indicate stimulation of local immune mechanisms. The results of this study showed an increase in the concentrations of APPs such as AGP and TRF following the administration of zinc glycine chelates, which may demonstrate their effect on metabolic processes in the liver and on immunocompetent cells that regulate the intensity of the immune response.

Quantum Dot Based Nano-Biosensors for Detection of Circulating Cell Free miRNAs in Lung Carcinogenesis: From Biology to Clinical Translation

Lung cancer is the most frequently occurring malignancy and the leading cause of cancer-related death for men in our country. The only recommended screening method is clinic based low-dose computed tomography (also called a low-dose CT scan, or LDCT). However, the effect of LDCT on overall mortality observed in lung cancer patients is not statistically significant. Over-diagnosis, excessive cost, risks associated with radiation exposure, false positive results and delay in the commencement of the treatment procedure questions the use of LDCT as a reliable technique for population-based screening. Therefore, identification of minimal-invasive biomarkers able to detect malignancies at an early stage might be useful to reduce the disease burden. Circulating nucleic acids are emerging as important source of information for several chronic pathologies including lung cancer. Of these, circulating cell free miRNAs are reported to be closely associated with the clinical outcome of lung cancer patients. Smaller size, sequence homology between species, low concentration and stability are some of the major challenges involved in characterization and specific detection of miRNAs. To circumvent these problems, synthesis of a quantum dot based nano-biosensor might assist in sensitive, specific and cost-effective detection of differentially regulated miRNAs. The wide excitation and narrow emission spectra of these nanoparticles result in excellent fluorescent quantum yields with a broader color spectrum which make them ideal bio-entities for fluorescence resonance energy transfer (FRET) based detection for sequential or simultaneous study of multiple targets. In addition, photo-resistance and higher stability of these nanoparticles allows extensive exposure and offer state-of-the art sensitivity for miRNA targeting. A major obstacle for integrating QDs into clinical application is the QD-associated toxicity. However, the use of non-toxic shells along with surface modification not only overcomes the toxicity issues, but also increases the ability of QDs to quickly detect circulating cell free miRNAs in a non-invasive mode. The present review illustrates the importance of circulating miRNAs in lung cancer diagnosis and highlights the translational prospects of developing QD-based nano-biosensor for rapid early disease detection.

Rituximab Therapy in Renal Amyloidosis Secondary to Rheumatoid Arthritis

Secondary amyloid A (AA) amyloidosis is a late and serious complication of poorly controlled, chronic inflammatory diseases. Rheumatoid arthritis (RA) patients with poorly controlled, longstanding disease and those with extra-articular manifestations are under risk for the development of AA amyloidosis. Although new drugs have proven to be significantly effective in the treatment of secondary AA amyloidosis, no treatment modality has proven to be ideal. To date, only in small case series preliminary clinical improvement have been shown with rituximab therapy for AA amyloidosis secondary to RA that is refractory to TNF-α inhibitors (TNF-i) therapy. In these case series, we assessed the efficacy and safety of rituximab therapy for patients with RA and secondary amyloidosis. Hacettepe University Biologic Registry was developed at 2005. The data of the RA patients who were prescribed a biological drug were recorded regularly. Patients with biopsy proven AA amyloidosis patients were screened. Of 1022 RA patients under biologic therapy, 0.7% patients had clinically apparent histologically confirmed amyloidosis. Four of seven patients who were prescribed rituximab at least one infusion enrolled to those case series. Two of four patients showed significant clinical improvement and one of them also had decrease in proteinuria and the other one had stable renal function and proteinuria. The main goal for the treatment of AA amyloidosis is to control the activity of the underlying disorder. In this study, we showed that rituximab may be an effective treatment in RA patients with amyloidosis who were unresponsive to conventional disease modifying anti-rheumatic drugs (DMARDs) and/or TNFi.

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.

Heroin Use Is Associated with AA-Type Kidney Amyloidosis in the Pacific Northwest

BACKGROUND AND OBJECTIVES

AA-type kidney amyloidosis is classically associated with chronic autoimmune or inflammatory disorders. However, some urban centers have reported a high prevalence of injection drug use among patients with kidney AA amyloidosis. Previous reports lack control groups to quantify associations and most predate the opioid epidemic in the United States.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a case-control study of 38 patients with biopsy-confirmed kidney AA amyloidosis and 72 matched control individuals without this condition from two large hospital systems in Seattle, Washington. We ascertained the pattern and duration of heroin use by medical chart review and determined associations using logistic regression.

RESULTS

Among case patients, 95% had a prior history of heroin use, 87% had skin abscesses, and 76% and 27% had evidence of muscling and skin popping, respectively. After adjustment for age, race, sex, site, and year of biopsy, any heroin use (past or current) was associated with an estimated 170-times higher risk of kidney AA amyloidosis compared with no heroin use (95% confidence interval, 28 to 1018 times higher; P<0.001). Chronic autoimmune disorders were uncommon among case patients in this study. The median time to ESKD among patients with AA amyloidosis was 2.4 years (interquartile range, 0.5-7.5 years).

CONCLUSIONS

Injection heroin use is strongly associated with kidney AA amyloidosis in the Pacific Northwest. Unique aspects of heroin use, in particular geographic regions or frequent associated soft-tissue infections, may be an important cause of this progressive kidney disease.

Efficacy and safety of interleukin-1 inhibitors in familial Mediterranean fever patients complicated with amyloidosis

BACKGROUND

Colchicine is the mainstay of the treatment of familial Mediterranean fever (FMF). However, 10% of FMF patients do not respond well to colchicine. Efficacy of interleukin (IL)-1 inhibitors in reducing attacks have been demonstrated in colchicine-resistant FMF (crFMF) patients recently. Colchicine is still the only approved drug for the prevention of amyloidosis in FMF and utility of IL-1 inhibitors in crFMF cases who already has amyloidosis remain to be elucidated. Herein, we evaluated efficacy and safety of IL-1 inhibitors in patients with crFMF-associated AA amyloidosis in a relatively large single center study.

METHODS

Medical records of FMF patients complicated with AA amyloidosis in our dedicated FMF center were retrospectively reviewed and those patients who ever treated with IL-1 inhibitors were enrolled into the study. Patient global, physician global assessments (on 0-10 cm visual analog scale), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), serum creatinine and 24-h urinary protein excretion values for each visit were recruited from computer-based hospital records. Treatment response of patients were assessed with clinical symptoms, serum albumin, CRP and ESR values. Renal outcome parameters were analyzed on those not receiving renal replacement therapy.

RESULTS

Seventeen patients were identified with crFMF-amyloidosis that ever treated with IL-1 inhibitors. Background colchicine therapy was continued in all patients in maximal-tolerated dose along with IL-1 inhibitors. All patients benefit from IL-1 antagonists assessed by patient and physician global assessments. Inflammatory markers, CRP and ESR, were significantly reduced in all and normalized in 12 out of 17 patients. More importantly, the amount of proteinuria was remarkably improved following IL-1 inhibitor therapy (1606 mg/day to 519 mg/day, p = .008). Both anakinra and canakinumab were well-tolerated without severe side effects. All patients were initially treated with anakinra but switched to canakinumab in seven patients (one leukopenia, four injection site reaction, two inefficacy).

CONCLUSION

We evaluated the clinical and laboratory responses to IL-1 inhibitors in crFMF-associated amyloidosis patients. We found significant decreases in CRP, ESR and proteinuria after IL-1 inhibitor therapy. This study confirmed that IL-1 inhibitors are effective for controlling attacks and inflammatory activity in FMF patients complicated with AA amyloidosis. Moreover, they reduce or stabilize amount of proteinuria and preserve renal function in short-term follow-up. Prolonged prospective clinical trials are warranted to assess their long-term efficacy in this particular patient group.

Serum Amyloid A, Properdin, Complement 3, and Toll-Like Receptors are Expressed Locally in Human Sinonasal Tissue

Background

There is a growing appreciation of the role that nasal mucosa plays in innate immunity. In this study, the expression of pattern recognition receptors known as toll-like receptors (TLRs) and the effector molecules complement factor 3 (C3), properdin, and serum amyloid A (SAA) were examined in human sinonasal mucosa obtained from control subjects and patients with chronic rhinosinusitis (CRS).

Methods

Sinonasal mucosal specimens were obtained from 20 patients with CRS and 5 control subjects. Messenger RNA (mRNA) was isolated and tested using Taqman real-time polymerase chain reaction with primer and probe sets for C3, complement factor P, and SAA. Standard polymerase chain reaction was performed for the 10 known TLRs. Immunohistochemistry was performed on the microscopic sections using antibodies against C3

Results

Analysis of the sinonasal sample mRNA revealed expression of all 10 TLRs in both CRS samples and in control specimens. Expression of the three effector proteins was detected also, with the levels of mRNA for C3 generally greater than SAA and properdin in CRS patients. No significant differences were found in TLR or innate immune protein expression in normal controls. Immunohistochemical analysis of sinonasal mucosal specimens established C3 staining ranging from 20 to 85% of the epithelium present.

Conclusion

These studies indicate that sinonasal mucosa expresses genes involved in innate immunity including the TLRs and proteins involved in complement activation. We hypothesize that local production of complement and acute phase proteins by airway epithelium on stimulation of innate immune receptors may play an important role in host defense in the airway and, potentially, in the pathogenesis of CRS.

Celiac Disease and Secondary Amyloidosis: A Possible Causal Association?

We report a rare case of secondary renal amyloidosis in a patient with probable celiac disease presenting as nephrotic syndrome. A 30-year-old man with chronic diarrhea presented with progressive anasarca for 2 years. On further evaluation, he had hypoalbuminemia, significant nephrotic-range proteinuria, and elevated levels of anti-tissue transglutaminase. Renal biopsy suggested deposition of amorphous Congo red–positive material in the glomerular mesangium, positive for amyloid A amyloidosis. Endoscopic duodenal biopsy suggested blunting of the villous architecture and chronic inflammation of the lamina propria. The patient subsequently developed massive pulmonary embolism and died due to refractory cardiogenic shock.

Serum Amyloid A1 Is an Epithelial Prorestitutive Factor

Several proteins endogenously produced during the process of intestinal wound healing have demonstrated prorestitutive properties. The presence of serum amyloid A1 (SAA1), an acute-phase reactant, within inflamed tissues, where it exerts chemotaxis of phagocytes, is well recognized; however, a putative role in intestinal wound repair has not been described. Herein, we show that SAA1 induces intestinal epithelial cell migration, spreading, and attachment through a formyl peptide receptor 2-dependent mechanism. Induction of the prorestitutive phenotype is concentration and time dependent and is associated with epithelial reactive oxygen species production and alterations in p130 Crk-associated substrate staining. In addition, using a murine model of wound recovery, we provide evidence that SAA1 is dynamically and temporally regulated, and that the elaboration of SAA1 within the wound microenvironment correlates with the influx of SAA1/CD11b coexpressing immune cells and increases in cytokines known to induce SAA expression. Overall, the present work demonstrates an important role for SAA in epithelial wound recovery and provides evidence for a physiological role in the wound environment.

Different Associations of Plasma Biomarkers in Alzheimer's Disease, Mild Cognitive Impairment, Vascular Dementia, and Ischemic Stroke

Background and Purpose

Cognitive and cerebrovascular diseases are common in the elderly, but differences in the plasma levels and associations of plasma biomarkers in these diseases remain elusive.

Methods

The present study investigated differences in plasma fatty acids [eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)], adiponectin, reptin, plasma markers of inflammation [high-sensitivity C-reactive protein (hsCRP) and serum amyloid A (serum AA)], and plasma lipids [high-density lipoprotein and low-density lipoprotein (LDL)] in patients with Alzheimer's disease (AD) (n=266), mild cognitive impairment (MCI) (n=44), vascular dementia (VaD) (n=33), and ischemic stroke (IS) (n=200) in comparison to normal controls (n=130).

Results

The serological data showed that lower EPA and DHA levels and higher reptin and LDL levels were associated with AD and IS, the reptin/adiponectin ratio was strongly associated with IS, the hsCRP level was more strongly associated with VaD and IS, and the serum AA level was associated with all three cognitive diseases and IS.

Conclusions

This is the first report of differences in the expression levels of plasma biomarkers and peripheral arterial tonometry among AD, MCI, VaD, and IS patients and normal controls. These different associations indicate that diverse pathological mechanisms underlie these diseases.

Serum amyloid A expression in the breast cancer tissue is associated with poor prognosis

Background

Serum amyloid A (SAA), an acute-phase protein, is expressed primarily in the liver, and recently found also expressed in cancer tissues. However, its expression and prognostic value in breast cancer have not been described.

Results

SAA protein was found expressed in tumor cells in 44.2% cases and in TAM in 62.5% cases. FISH showed more frequent SAA mRNA expression in TAM than in tumor cells (76% versus 12%, p < 0.001), and a significant association between the frequencies of SAA mRNA expression in TAM and tumor cells (r_s = 0.603, p < 0.001). The immunoreactivities of SAA protein in TAM and tumor cells were both associated with lymphovascular invasion and lymph node metastasis. Moreover, SAA-positivity in TAMs was associated with larger tumor-size, higher histological-grade, negative estrogen-receptor and progesterone-receptor statuses, and HER-2 overexpression. It was also linked to worse recurrence-free survival in a multivariable regression model.

Methods

Immunohistochemistry was applied on the tumor tissues from 208 breast cancer patients to evaluate the local SAA-protein expression with additional CD68 stain to identify the tumor-associated macrophage (TAM) on the serial tissue sections. Fluorescent in situ hybridization (FISH) was conducted on serial tissue sections from 25 of the 208 tumors to examine the expression and location of SAA mRNA.

Conclusions

Our results suggested that the TAMs may be a pivotal and main source of SAA production in tumor microenvironment of breast cancer. SAA immunoreactivity in TAM is associated with worse recurrence-free survival, and is therefore a biomarker candidate for postoperative surveillance and perhaps a therapeutic target for breast cancer.

Aberrant hepatic lipid storage and metabolism in canine portosystemic shunts

Non-alcoholic fatty liver disease (NAFLD) is a poorly understood multifactorial pandemic disorder. One of the hallmarks of NAFLD, hepatic steatosis, is a common feature in canine congenital portosystemic shunts. The aim of this study was to gain detailed insight into the pathogenesis of steatosis in this large animal model. Hepatic lipid accumulation, gene-expression analysis and HPLC-MS of neutral lipids and phospholipids in extrahepatic (EHPSS) and intrahepatic portosystemic shunts (IHPSS) was compared to healthy control dogs. Liver organoids of diseased dogs and healthy control dogs were incubated with palmitic- and oleic-acid, and lipid accumulation was quantified using LD540. In histological slides of shunt livers, a 12-fold increase of lipid content was detected compared to the control dogs (EHPSS P<0.01; IHPSS P = 0.042). Involvement of lipid-related genes to steatosis in portosystemic shunting was corroborated using gene-expression profiling. Lipid analysis demonstrated different triglyceride composition and a shift towards short chain and omega-3 fatty acids in shunt versus healthy dogs, with no difference in lipid species composition between shunt types. All organoids showed a similar increase in triacylglycerols after free fatty acids enrichment. This study demonstrates that steatosis is probably secondary to canine portosystemic shunts. Unravelling the pathogenesis of this hepatic steatosis might contribute to a better understanding of steatosis in NAFLD.

Serum amyloid A enrichment impairs the anti-inflammatory ability of HDL from diabetic nephropathy patients

AIMS

Impaired anti-inflammatory ability of high-density lipoprotein (HDL) has been demonstrated in patients with type-2 diabetes mellitus (T2DM). However, whether HDL from patients with diabetic nephropathy (DN) suffers additional damage remains unknown. This study compared the anti-inflammatory capacities of HDL from healthy controls, T2DM patients with normal renal function, and T2DM patients with DN.

MATERIALS AND METHODS

HDL was isolated from healthy controls (n=33) and T2DM patients with normal renal function (n=21), chronic kidney disease (CKD) (n=27), and end-stage renal disease (ESRD) (n=27). Human peripheral blood mononuclear cells (PBMCs) from healthy volunteers were pretreated with HDL (100μg/mL) for 1h, then incubated with lipopolysaccharide (LPS) (50ng/mL) for 24h. The anti-inflammatory ability of HDL was measured as the secretion of TNF-α in LPS-activated monocytes.

RESULTS

The anti-inflammatory ability of HDL was gradually impaired as kidney function declined. Serum amyloid A (SAA) concentration in HDL^DN significantly increased and was positively correlated with the impaired anti-inflammatory ability of HDL (Pearson r=0.315, P=0.006). Furthermore, HDL supplemented with SAA significantly increased TNF-α release from PBMCs compared with that from control HDL.

CONCLUSIONS

These findings identified an impaired anti-inflammatory capacity of HDL from DN patients, which might be attributable to SAA enrichment.

Toll Like Receptors in systemic sclerosis: An emerging target

Pattern Recognition Receptors are critical receptors that elicit an immune response upon their activation that culminates in activation of NF-KB and cytokine secretion. Key among these receptors are the Toll-Like Receptors (TLRs). These evolutionary conserved receptors form a key part in the defence against various pathogens and comprise a key part of the innate immune system. Systemic sclerosis is an autoimmune disease in which a breach of tolerance has occurred and leads to fulminant autoimmunity, dysregulated cytokines, pro-fibrotic mediators and activation of fibroblasts leading to fibrosis via collagen deposition. It has become apparent in recent years that the innate immune system and specifically TLRs are important in disease pathogenesis; responding to internal ligands to initiate an innate immune response ultimately leading to release of a variety of factors that initiate and perpetuate fibrosis. This review will examine the recent evidence of TLR signalling in systemic sclerosis and the internal danger associated molecules that may mediate the fibrotic cascade. Evaluation of their contribution to disease in systemic sclerosis and possible therapeutic targeting will be discussed.

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.

Serum amyloid A self-assembles with phospholipids to form stable protein-rich nanoparticles with a distinct structure: A hypothetical function of SAA as a "molecular mop" in immune response

Serum amyloid A (SAA) is an acute-phase protein whose action in innate immunity and lipid homeostasis is unclear. Most circulating SAA binds plasma high-density lipoproteins (HDL) and reroutes lipid transport. In vivo SAA binds existing lipoproteins or generates them de novo upon lipid uptake from cells. We explored the products of SAA-lipid interactions and lipoprotein remodeling in vitro. SAA complexes with palmitoyl-oleoyl phosphocholine (POPC) were analyzed for structure and stability using circular dichroism and fluorescence spectroscopy, electron microscopy, gel electrophoresis and gel filtration. The results revealed the formation of 8-11nm lipoproteins that were∼50% α-helical and stable at near-physiological conditions but were irreversibly remodeled at T_m∼52°C. Similar HDL-size nanoparticles formed spontaneously at ambient conditions or upon thermal remodeling of parent lipoproteins containing various amounts of proteins and lipids, including POPC and cholesterol. Therefore, such HDL-size particles formed stable kinetically accessible structures in a wide range of conditions. Based on their size and stoichiometry, each particle contained about 12 SAA and 72 POPC molecules, with a protein:lipid weight ratio circa 2.5:1, suggesting a structure distinct from HDL. High stability of these nanoparticles and their HDL-like size suggest that similar lipoproteins may form in vivo during inflammation or injury when SAA concentration is high and membranes from dead cells require rapid removal. We speculate that solubilization of membranes by SAA to generate lipoproteins in a spontaneous energy-independent process constitutes the primordial function of this ancient protein, providing the first line of defense in clearing cell debris from the injured sites.

Identification of a panel of serum protein markers in early stage of sepsis and its validation in a cohort of patients

BACKGROUND

Sepsis is a life-threatening illness with a challenging diagnosis. Current serum biomarkers are not sensitive enough for diagnosis. With the aim of finding proteins associated with sepsis, serum protein profile was compared between patients and healthy donors and serum classical inflammatory proteins were analyzed in both groups.

METHODS

Serum protein profiles were characterized by two-dimensional electrophoresis (2DE). Identification of the proteins was carried out by mass spectrophotometry and their validation was performed by Enzyme-Linked-ImmunoSorbent Assay (ELISA) in a cohort of 85 patients and 67 healthy donors. Seven classical inflammatory proteins were analyzed in the same cohort by ELISA: interleukin-2 receptor α-chain (sCD25), scavenger receptor cysteine-rich-type-1 (sCD163), tumor-necrosis factor receptor superfamily-member-6 (sFas), hemeoxigenase-1 decycling (HO-1), interleukin-6 (IL-6), interleukin-18 (IL-18) and intercellular adhesion-molecule-1 (sICAM-1).

RESULTS

After 2DE, 20 significantly differently expressed spots were identified by mass spectrometry analysis, revealing deregulation of six different proteins upon sepsis and 50% were validated by ELISA: Antithrombin-III (AT-III), Clusterin (CLUS) and Serum amyloid A-1 (SAA-1). Serum concentration of AT-III and CLUS was significantly lower in patients' serum, whereas SAA-1 showed higher values in septic patients. Serum concentration of the seven inflammatory proteins was significantly increased in septic patients. Functional analysis of the ten deregulated proteins revealed an enrichment of proteins related mainly to the activation of the immune response.

CONCLUSION

We have identified a panel of ten potential sepsis marker proteins biologically connected and validated in a large number of patients, whose analysis could be considered as a complementary tool for the diagnosis of sepsis.

Serum Amyloid A Induces a Vascular Smooth Muscle Cell Phenotype Switch through the p38 MAPK Signaling Pathway

Atherosclerosis is an important pathological condition which is accompanied by a vascular smooth muscle cell (VSMC) phenotype switch toward a synthetic phenotype. As an acute-phase protein, Serum Amyloid A (SAA) is thought to have a close relationship to atherosclerosis development. However, no study has investigated the direct effect of SAA on the VSMC phenotype switch, as well as the underlying mechanisms. The purpose of our study was to explore the effect of SAA on the VSMC phenotype switch and the potential mechanisms involved. In our study, we found that SAA induced the VSMC phenotype switch which reduced expression of the smooth muscle cell (SMC) marker and enhanced expression of the matrix synthesis related marker. The proliferative ability of VSMCs was also increased by SAA treatment. Furthermore, our research found that SAA activated the ERK1/2 and p38 MAPK signaling pathways. Finally, by applying the ERK1/2 and p38 inhibitors, U0126 and SB203580, we demonstrated that the SAA-induced VSMC phenotype switch was p38-dependent. Taken together, these results indicated that SAA may play an important role in promoting the VSMC phenotype switch through the p38 MAPK signaling pathway.

Tocilizumab in the treatment of twelve cases with aa amyloidosis secondary to familial mediterranean fever

Background

There is no established treatment of AA amyloidosis, a long-term complication of various chronic inflammatory diseases associated with increased mortality, such as familial Mediterranian fever (FMF). Recently there are few reports pointing out that tocilizumab(TCZ), an anti IL-6 agent may be effective in AA amyloidosis resistant to conventional treatments. We report our data on the effect of TCZ in patients with FMF complicated with AA amyloidosis.

Methods

FMF patients with histologically proven AA amyloidosis, treated with TCZ (8 mg/kg per month) were followed monthly and the changes in creatinine, creatinine clearance, the amount of 24-hour urinary protein, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were noted throughout the treatment period. Adverse effects of the treatment were closely monitored.

Results

TCZ was given to 12 patients (6 F, 6 M) who also continued to receive colchicine (1.9 ± 0.4 mg/day). Coexisting diseases were ankylosing spondylitis(4) and Crohn’s disease(1). The mean age was 35.2 ± 10.0 years and the mean follow-up on TCZ was 17.5 ± 14.7 months. The renal functions remained stable (mean creatinine from 1.1 ± 0.9 mg/dl to 1.0 ± 0.6 mg/dl), while a significant decrease in acute phase response (the mean CRP from 18.1 ± 19.5 mg/L to 5.8 ± 7.1 mg/L and ESR from 48.7 ± 31.0 mm/h to 28.7 ± 28.3 mm/h) was observed and the mean 24-hour urinary protein excretion reduced from 6537.6 ± 6526.0 mg/dl to 4745.5 ± 5462.7 mg/dl. Two patients whose renal functions were impaired prior to TCZ therapy improved significantly on this regimen. No infusion reaction was observed. None of the patients experienced any FMF attack under TCZ treatment with the exception of 2, one of whom had less frequent attacks while the other had episodes of erysipelas-like erythema.

Conclusıon

Tocilizumab improved the acute phase response and the renal function in this group of patients and was generally well tolerated. Besides improving the renal function TCZ seemed to control the recurrence of FMF attacks too. Further studies are warrented to test the efficacy and safety of TCZ in AA amyloidosis secondary to FMF as well as other inflammatory conditions.

Augmented Serum Amyloid A1/2 Mediated by TNF-induced NF-κB in Human Serous Ovarian Epithelial Tumors

Tumor necrosis factor-α (TNF) is well known to be involved in the immune system and ovarian inflammation. Ovarian cancer is an inflammation-related malignancy that lacks early screening strategies, resulting in late diagnosis followed by high mortality. Based on our previous data, TNF induced abundant serum amyloid A (SAA), an acute phase protein linked to inflammation, in ovarian granulosal cells. To date, the regulation and expression of SAA in ovarian cancer is not fully elucidated. Here, we investigated the relationship between TNF and SAA by comparing human normal ovarian tissues and serous ovarian tumors. We found that SAA1/2 was significantly expressed in tumor tissues, but no or trace expression levels in normal tissues. TNF was also significantly upregulated in ovarian tumor tissues compared to normal tissues. Moreover, TNF significantly increased SAA1/2 levels in human ovarian cancer cell lines, OVCAR-3 and SKOV-3, in a time-dependent manner. Since the SAA1 promoter contains two nuclear factor (NF)-κB sites, we examined whether TNF regulates SAA1 promoter activity. Deletion analysis revealed that the proximal NF-κB site (-95/-85) played a critical role in regulating TNF-induced SAA1 promoter activity. Within 2 h after intraperitoneal injection of lipopolysaccharide, a product known to stimulate release of TNF, SAA preferably localized to ovarian epithelial cells and the thecal-interstitial layers compared to granulosal cell layers. Based on Gene Expression Omnibus (GEO) database, SAA1/2 and TNF were dominantly expressed in advanced grade ovarian cancer. Taken together, the accumulation of SAA1/2 in ovarian cancer could be mediated by TNF-induced NF-κB activation.

Human SR-BII mediates SAA uptake and contributes to SAA pro-inflammatory signaling in vitro and in vivo

Serum amyloid A (SAA) is an acute phase protein with cytokine-like and chemotactic properties, that is markedly up-regulated during various inflammatory conditions. Several receptors, including FPRL-1, TLR2, TLR4, RAGE, class B scavenger receptors, SR-BI and CD36, have been identified as SAA receptors. This study provides new evidence that SR-BII, splice variant of SR-BI, could function as an SAA receptor mediating its uptake and pro-inflammatory signaling. The uptake of Alexa Fluor488 SAA was markedly (~3 fold) increased in hSR-BII-expressing HeLa cells when compared with mock-transfected cells. The levels of SAA-induced interleukin-8 secretion by hSR-BII-expressing HEK293 cells were also significantly (~3-3.5 fold) higher than those detected in control cells. Moderately enhanced levels of phosphorylation of all three mitogen-activated protein kinases, ERK1/2, and p38 and JNK, were observed in hSR-BII-expressing cells following SAA stimulation when compared with control wild type cells. Transgenic mice with pLiv-11-directed liver/kidney overexpression of hSR-BI or hSR-BII were used to assess the in vivo role of each receptor in SAA-induced pro-inflammatory response in these organs. Six hours after intraperitoneal SAA injection both groups of transgenic mice demonstrated markedly higher (~2-5-fold) expression levels of inflammatory mediators in the liver and kidney compared to wild type mice. Histological examinations of hepatic and renal tissue from SAA-treated mice revealed moderate level of damage in the liver of both transgenic but not in the wild type mice. Activities of plasma transaminases, biomarkers of liver injury, were also moderately higher in hSR-B transgenic mice when compared to wild type mice. Our findings identify hSR-BII as a functional SAA receptor that mediates SAA uptake and contributes to its pro-inflammatory signaling via the MAPKs-mediated signaling pathways.

Induction of pro-inflammatory genes by serum amyloid A1 in human amnion fibroblasts

Serum amyloid A1 (SAA1) is an acute response protein, which is mainly produced by the liver, during infection. However, it remains unknown whether SAA1 can be produced in human fetal membranes where it is able to elicit events pertinent to labor initiation. We demonstrated that SAA1 was expressed in the fibroblasts and epithelium of the amnion and the trophoblasts of the chorion. Further study in human amnion fibroblasts showed that SAA1 production was augmented by interleukin-1β (IL-1β) and cortisol alone and synergistically, and SAA1 in turn induced the expression of IL-1β, interleukin-6 (IL-6), cyclooxygenase-2 (COX-2) and PGE2 production. These effects of SAA1 were mediated through activation of the NF-κB, p38 and ERK1/2 pathways via the toll-like receptor 4 (TLR4). Inhibition of TLR4 attenuated not only SAA1-induced activation of NF-κB, p38 and ERK1/2 but also increases in IL-1β, IL-6 and COX-2 expression. Moreover, SAA1 expression was increased in human amnion tissue following spontaneous labor. In conclusion, this study has demonstrated for the first time that SAA1 can be produced in human fetal membranes, which can be greatly induced in the presence of proinflammatory cytokines and glucocorticoids thereby producing effects associated with parturition.

Proteome alterations associated with transformation of multiple myeloma to secondary plasma cell leukemia

Plasma cell leukemia is a rare and aggressive plasma cell neoplasm that may either originate de novo (primary PCL) or by leukemic transformation of multiple myeloma (MM) to secondary PCL (sPCL). The prognosis of sPCL is very poor, and currently no standard treatment is available due to lack of prospective clinical studies. In an attempt to elucidate factors contributing to transformation, we have performed super-SILAC quantitative proteome profiling of malignant plasma cells collected from the same patient at both the MM and sPCL stages of the disease. 795 proteins were found to be differentially expressed in the MM and sPCL samples. Gene ontology analysis indicated a metabolic shift towards aerobic glycolysis in sPCL as well as marked down-regulation of enzymes involved in glycan synthesis, potentially mediating altered glycosylation of surface receptors. There was no significant change in overall genomic 5-methylcytosine or 5-hydroxymethylcytosine at the two stages, indicating that epigenetic dysregulation was not a major driver of transformation to sPCL. The present study constitutes the first attempt to provide a comprehensive map of the altered protein expression profile accompanying transformation of MM to sPCL in a single patient, identifying several candidate proteins that can be targeted by currently available small molecule drugs. Our dataset furthermore constitutes a reference dataset for further proteomic analysis of sPCL transformation.

Maternal serum amyloid A level as a novel marker of primary unexplained recurrent early pregnancy loss

OBJECTIVE

To assess maternal serum amyloid A (SAA) levels among women with primary unexplained recurrent early pregnancy loss (REPL).

METHODS

A prospective study was conducted among women with missed spontaneous abortion in the first trimester at Ain Shams University Maternity Hospital, Cairo, Egypt, between January 21 and December 25, 2014. Women with at least two consecutive primary unexplained REPLs and no previous live births were enrolled. A control group was formed of women with no history of REPL who had at least one previous uneventful pregnancy with no adverse outcomes. Serum samples were collected to measure SAA levels. The main outcome was the association between SAA and primary unexplained REPL.

RESULTS

Each group contained 96 participants. Median SAA level was significantly higher among women with REPL (50.0 μg/mL, interquartile range 26.0-69.0) than among women in the control group (11.6 μg/mL, interquartile range 6.2-15.5; P<0.001). The SAA level was an independent indicator of primary unexplained REPL, after adjusting for maternal age and gestational age (odds ratio 1.12, 95% confidence interval 1.06-1.19; P<0.001).

CONCLUSION

Elevated SAA levels found among women with primary unexplained REPL could represent a novel biomarker for this complication of pregnancy.

The diagnostic accuracy of acute phase proteins and proinflammatory cytokines in sheep with pneumonic pasteurellosis

The goal of this study was to assess the diagnostic accuracy of acute phase proteins and proinflammatory cytokines in sheep with pneumonic pasteurellosis. Blood samples were collected from 56 sheep (36 naturally infected with Pasteurella multocida and 20 healthy controls) belonging to one farm in Eastern region, Saudi Arabia. Serum samples were evaluated for acute phase proteins (Haptoglobin (Hp), serum amyloid A (SAA) and fibrinogen (Fb)), and the proinflammatory cytokines (interleukins (IL-1α, IL-1β, and IL-6), tumor necrosis factor-alpha (TNF-α), and interferon-gamma (IFN-ϒ)). Additionally, nasopharyngeal swabs and bronchoalveolar lavages were collected from all animals for bacteriological examinations. Receiver operating characteristic curve was used to assess the diagnostic performance of each parameter. All parameters showed moderate to high degree of positive correlation with case-control status. There was no significant difference in the area under the curve (AUC) among acute phase proteins; however, both Hp and SAA showed better sensitivity and specificity than Fb. The proinflammatory cytokines (IL1-α, IL1-β, and IL6) showed similar and highly accurate diagnostic performance (AUC > 0.9), whereas IFN-ϒ was moderately accurate (AUC = 0.79). In conclusion, this study confirms the value of acute phase proteins and cytokines as diagnostic biomarkers of naturally occuring pneumonic pasteurellosis in sheep.

Plasma proteomics for the assessment of acute renal transplant rejection

Renal transplant is the best treatment for patients with chronical kidney disease however acute graft rejection is the major impediment to success in renal transplantation leading to loss of the organ the first year after transplantation. The aim of this study was to identify plasma proteins that may be early biomarkers of acute rejection of renal allograft, developing a diagnostic model that avoids the loss of the transplanted organ. Shotgun proteomics (LC-MS/MS) method was used to analyze a set of thirty-one plasma samples, including 06 from patients with acute graft rejection after transplantation (rejection group/Rej-group) and twenty-five from renal transplant patients with stable renal graft function (control group/Ct-group). As results nineteen proteins were upregulated in the rejection group compared to the control group, and two proteins were downregulated; and three were present exclusively in the rejection group. After analysis, we selected four proteins that were related to the acute phase response and that were strongly associated with each other: they are alpha-1 antitrypsin (A1AT), alpha-2 antiplasmin (A2AP), serum amyloid A (SAA) and apolipoprotein CIII (APOC3). We think that simultaneous monitoring of SAA and APOC3 can provide insights into a broad profile of signaling proteins and is highly valuable for the early detection of a possible acute renal graft rejection.

STATEMENT OF SIGNIFICANCE OF THE STUDY

In this study we did plasma shotgun patients with and without acute rejection of renal allograft. In a clinical setting an acute rejection is typically suspected upon an increase in plasma creatinine and renal biopsy. But these methods are late and unspecific; sometimes the rejection process is already advanced when there is an increase in serum creatinine. Therefore, it is necessary to find proteins that can predict the allograft rejection process. In our study were able to identify changes in the concentration of plasma protein belonging to a network of protein interaction processes the acute phase response. We believe, therefore, that development of a routine diagnosis of these proteins can detect early acute rejection of renal allograft process, thus preventing its loss.

Acute serum amyloid A is an endogenous TLR2 ligand that mediates inflammatory and angiogenic mechanisms

INTRODUCTION

Acute-phase serum amyloid A (A-SAA) has cytokine-like properties and is expressed at sites of inflammation. We examined whether A-SAA-induced pro-inflammatory mechanisms are mediated through Toll-like receptor 2 (TLR2) in rheumatoid arthritis (RA).

METHODS

The effect of A-SAA on human embryonic kidney (HEK), TLR2 or TLR4 cells was quantified by nuclear factor (NF)-κB luciferase reporter assays. A-SAA-induced RASFC and dHMVEC function were performed in the presence of a specific neutralising anti-TLR2 mAb (OPN301) (1 μg/mL) and matched IgG isotype control Ab (1 μg/mL). Cell surface expression of intracellular adhesion molecule (ICAM)-1, chemokine expression, cell migration, invasion and angiogenesis were assessed by flow cytometry, ELISA, Matrigel invasion chambers and tube formation assays. MyD88 expression was assessed by real-time PCR and western blot.

RESULTS

A-SAA induced TLR2 activation through induction of NF-κB (p<0.05), but failed to induce NF-κB in HEK-TLR4 cells, confirming specificity for TLR2. A-SAA-induced proliferation, invasion and migration were significantly inhibited in the presence of anti-TLR2 (all p<0.05), with no significant effect observed for tumour necrosis factor-α-induced events. Additionally, A-SAA-induced ICAM-1, interleukin-8, monocyte chemoattractant protein-1, RANTES and GRO-α expression were significantly reduced in the presence of anti-TLR2 (all p<0.05), as was A-SAA induced angiogenesis (p<0.05). Finally, A-SAA induced MyD88 signalling in RASFC and dHMVEC (p<0.05).

CONCLUSIONS

A-SAA is an endogenous ligand for TLR2, inducing pro-inflammatory effects in RA. Blocking the A-SAA/TLR2 interaction may be a potential therapeutic intervention in RA.

Transcriptomic Approaches in the Zebrafish Model for Tuberculosis-Insights Into Host- and Pathogen-specific Determinants of the Innate Immune Response

Mycobacterium marinum infection in zebrafish has become a well-established model of tuberculosis. Both embryonic and adult zebrafish infection studies have contributed to our knowledge of the development and function of tuberculous granulomas, which are typical of mycobacterial pathogenesis. In this review we discuss how transcriptome profiling studies have helped to characterize this infection process. We illustrate this using new RNA sequencing (RNA-Seq) data that reveals three main phases in the host response to M. marinum during the early stages of granuloma development in zebrafish embryos and larvae. The early phase shows induction of complement and transcription factors, followed by a relatively minor induction of pro-inflammatory cytokines within hours following phagocytosis of M. marinum. A minimal response is observed in the mid-phase, between 6 hours and 1day post infection, when the tissue dissemination of M. marinum begins. During subsequent larval development the granulomas expand and a late-phase response is apparent, which is characterized by progressively increasing induction of complement, transcription factors, pro-inflammatory cytokines, matrix metalloproteinases, and other defense and inflammation-related gene groups. This late-phase response shares common components with the strong and acute host transcriptome response that has previously been reported for Salmonella typhimurium infection in zebrafish embryos. In contrast, the early/mid-phase response to M. marinum infection, characterized by suppressed pro-inflammatory signaling, is strikingly different from the acute response to S. typhimurium infection. Furthermore, M. marinum infection shows a collective and strongly fluctuating regulation of lipoproteins, while S. typhimurium infection has pronounced effects on amino acid metabolism and glycolysis.

Vitronectin and dermcidin serum levels predict the metastatic progression of AJCC I-II early-stage melanoma

Like many cancers, an early diagnosis of melanoma is fundamental to ensure a good prognosis, although an important proportion of stage I-II patients may still develop metastasis during follow-up. The aim of this work was to discover serum biomarkers in patients diagnosed with primary melanoma that identify those at a high risk of developing metastasis during the follow-up period. Proteomic and mass spectrophotometry analysis was performed on serum obtained from patients who developed metastasis during the first years after surgery for primary tumors and compared with that from patients who remained disease-free for more than 10 years after surgery. Five proteins were selected for validation as prognostic factors in 348 melanoma patients and 100 controls by ELISA: serum amyloid A and clusterin; immune system proteins; the cell adhesion molecules plakoglobin and vitronectin and the antimicrobial protein dermcidin. Compared to healthy controls, melanoma patients have high serum levels of these proteins at the moment of melanoma diagnosis, although the specific values were not related to the histopathological stage of the tumors. However, an analysis based on classification together with multivariate statistics showed that tumor stage, vitronectin and dermcidin levels were associated with the metastatic progression of patients with early-stage melanoma. Although melanoma patients have increased serum dermcidin levels, the REPTree classifier showed that levels of dermcidin <2.98 μg/ml predict metastasis in AJCC stage II patients. These data suggest that vitronectin and dermcidin are potent biomarkers of prognosis, which may help to improve the personalized medical care of melanoma patients and their survival.