Recognition functions of pentameric C-reactive protein in cardiovascular disease

A tale of two functions: C-reactive protein complement-ary structures and their role in rheumatoid arthritis

C-reactive protein (CRP) is an inflammatory biomarker with associated clinical utility in a wide number of inflammatory disorders, including rheumatoid arthritis (RA). The interaction of CRP with pro-inflammatory cytokines has been explored before, however its role in complement regulation is more subtle, where CRP is capable of both up and downregulating the complement cascade. CRP is produced in a pentameric form and can dissociate to a monomeric form in circulation which has significant implications for its ability to interact with receptors and binding partners. This dichotomy of CRP structure could have relevance in patients with RA who have significant dysfunction in their complement cascade and also widely varying CRP levels including at the time of flare. This review aims to bring together current knowledge of CRP in its various forms, its effects on complement function and how this could influence pathology in the context of RA.

C-Reactive Protein: Pathophysiology, Diagnosis, False Test Results and a Novel Diagnostic Algorithm for Clinicians

The current literature provides a body of evidence on C-Reactive Protein (CRP) and its potential role in inflammation. However, most pieces of evidence are sparse and controversial. This critical state-of-the-art monography provides all the crucial data on the potential biochemical properties of the protein, along with further evidence on its potential pathobiology, both for its pentameric and monomeric forms, including information for its ligands as well as the possible function of autoantibodies against the protein. Furthermore, the current evidence on its potential utility as a biomarker of various diseases is presented, of all cardiovascular, respiratory, hepatobiliary, gastrointestinal, pancreatic, renal, gynecological, andrological, dental, oral, otorhinolaryngological, ophthalmological, dermatological, musculoskeletal, neurological, mental, splenic, thyroid conditions, as well as infections, autoimmune-supposed conditions and neoplasms, including other possible factors that have been linked with elevated concentrations of that protein. Moreover, data on molecular diagnostics on CRP are discussed, and possible etiologies of false test results are highlighted. Additionally, this review evaluates all current pieces of evidence on CRP and systemic inflammation, and highlights future goals. Finally, a novel diagnostic algorithm to carefully assess the CRP level for a precise diagnosis of a medical condition is illustrated.

Admixture mapping of severe asthma exacerbations in Hispanic/Latino children and youth

BACKGROUND

In the USA, genetically admixed populations have the highest asthma prevalence and severe asthma exacerbations rates. This could be explained not only by environmental factors but also by genetic variants that exert ethnic-specific effects. However, no admixture mapping has been performed for severe asthma exacerbations.

OBJECTIVE

We sought to identify genetic variants associated with severe asthma exacerbations in Hispanic/Latino subgroups by means of admixture mapping analyses and fine mapping, and to assess their transferability to other populations and potential functional roles.

METHODS

We performed an admixture mapping in 1124 Puerto Rican and 625 Mexican American children with asthma. Fine-mapping of the significant peaks was performed via allelic testing of common and rare variants. We performed replication across Hispanic/Latino subgroups, and the transferability to non-Hispanic/Latino populations was assessed in 1001 African Americans, 1250 Singaporeans and 941 Europeans with asthma. The effects of the variants on gene expression and DNA methylation from whole blood were also evaluated in participants with asthma and in silico with data obtained through public databases.

RESULTS

Genomewide significant associations of Indigenous American ancestry with severe asthma exacerbations were found at 5q32 in Mexican Americans as well as at 13q13-q13.2 and 3p13 in Puerto Ricans. The single nucleotide polymorphism (SNP) rs1144986 (C5orf46) showed consistent effects for severe asthma exacerbations across Hispanic/Latino subgroups, but it was not validated in non-Hispanics/Latinos. This SNP was associated with DPYSL3 DNA methylation and SCGB3A2 gene expression levels.

CONCLUSIONS

Admixture mapping study of asthma exacerbations revealed a novel locus that exhibited Hispanic/Latino-specific effects and regulated DPYSL3 and SCGB3A2.

Enhanced efficacy of direct immunochemotherapy for hepatic cancer with image-guided intratumoral radiofrequency hyperthermia

BACKGROUND

It is still a challenge to prevent tumor recurrence post radiofrequency ablation (RFA) of medium-to-large hepatocellular carcinomas (HCC). Immunochemotherapy, a combination of immunotherapy with chemotherapy, has demonstrated a great potential in augmenting the treatment efficacy for some malignancies. In this study, we validated the feasibility of using radiofrequency hyperthermia (RFH)-enhanced intratumoral immunochemotherapy of LTX-315 with liposomal doxorubicin for rat orthotopic HCC.

METHODS

Different groups of luciferase-labeled rat HCC cells and rat orthotopic HCC models were treated by: (1) phosphate buffered saline; (2) RFH; (3) LTX-315; (4) RFH+LTX-315; (5) liposomal doxorubicin; (6) RFH+liposomal doxorubicin; (7) LTX-315+liposomal doxorubicin; and (8) RFH+LTX-315+liposomal doxorubicin. Cell viabilities and apoptosis of different treatment groups were compared. Changes in tumor sizes were quantified by optical and ultrasound imaging, which were confirmed by subsequent histopathology. The potential underlying biological mechanisms of the triple combination treatment (RFH+LTX-315+liposomal doxorubicin) were explored.

RESULTS

Flow cytometry and MTS assay showed the highest percentage of apoptotic cells and lowest cell viability in the triple combination treatment group compared with other seven groups (p<0.001). Tumors in this group also presented the most profound decrease in bioluminescence signal intensities and the smallest tumor volumes compared with other seven groups (p<0.001). A significant increase of CD8⁺ T cells, CD8⁺/interferon (IFN)-γ⁺ T cells, CD8⁺/tumor necrosis factor (TNF)-α⁺ T cells, and natural killer cells, and a significant decrease of regulatory T cells were observed in the tumors (p<0.001). Meanwhile, a significantly higher level of Th1-type cytokines in both plasma (interleukin (IL)-2, IL-12, IL-18, IFN-γ) and tumors (IL-2, IL-18, IFN-γ, TNF-α), as well as a significantly lower Th2-type cytokines of IL-4 and IL-10 in plasma and tumor were detected.

CONCLUSIONS

Intratumoral RFA-associated RFH could enhance the efficacy of immunochemotherapy of LTX-315 with liposomal doxorubicin for HCC, which may provide a new strategy to increase the curative efficacy of thermal ablation for medium-to-large HCC.

Structurally Altered, Not Wild-Type, Pentameric C-Reactive Protein Inhibits Formation of Amyloid-β Fibrils

The structure of wild-type pentameric C-reactive protein (CRP) is stabilized by two calcium ions that are required for the binding of CRP to its ligand phosphocholine. CRP in its structurally altered pentameric conformations also binds to proteins that are denatured and aggregated by immobilization on microtiter plates; however, the identity of the ligand on immobilized proteins remains unknown. We tested the hypotheses that immobilization of proteins generated an amyloid-like structure and that amyloid-like structure was the ligand for structurally altered pentameric CRP. We found that the Abs to amyloid-β peptide 1-42 (Aβ) reacted with immobilized proteins, indicating that some immobilized proteins express an Aβ epitope. Accordingly, four different CRP mutants capable of binding to immobilized proteins were constructed, and their binding to fluid-phase Aβ was determined. All CRP mutants bound to fluid-phase Aβ, suggesting that Aβ is a ligand for structurally altered pentameric CRP. In addition, the interaction between CRP mutants and Aβ prevented the formation of Aβ fibrils. The growth of Aβ fibrils was also halted when CRP mutants were added to growing fibrils. Biochemical analyses of CRP mutants revealed altered topology of the Ca2+-binding site, suggesting a role of this region of CRP in binding to Aβ. Combined with previous reports that structurally altered pentameric CRP is generated in vivo, we conclude that CRP is a dual pattern recognition molecule and an antiamyloidogenic protein. These findings have implications for Alzheimer's and other neurodegenerative diseases caused by amyloidosis and for the diseases caused by the deposition of otherwise fluid-phase proteins.

Mapping the human gut mycobiome in middle-aged and elderly adults: multiomics insights and implications for host metabolic health

OBJECTIVE

The human gut fungal community, known as the mycobiome, plays a fundamental role in the gut ecosystem and health. Here we aimed to investigate the determinants and long-term stability of gut mycobiome among middle-aged and elderly adults. We further explored the interplay between gut fungi and bacteria on metabolic health.

DESIGN

The present study included 1244 participants from the Guangzhou Nutrition and Health Study. We characterised the long-term stability and determinants of the human gut mycobiome, especially long-term habitual dietary consumption. The comprehensive multiomics analyses were performed to investigate the ecological links between gut bacteria, fungi and faecal metabolome. Finally, we examined whether the interaction between gut bacteria and fungi could modulate the metabolic risk.

RESULTS

The gut fungal composition was temporally stable and mainly determined by age, long-term habitual diet and host physiological states. Specifically, compared with middle-aged individuals, Blastobotrys and Agaricomycetes spp were depleted, while Malassezia was enriched in the elderly. Dairy consumption was positively associated with Saccharomyces but inversely associated with Candida. Notably, Saccharomycetales spp interacted with gut bacterial diversity to influence insulin resistance. Bidirectional mediation analyses indicated that bacterial function or faecal histidine might causally mediate an impact of Pichia on blood cholesterol.

CONCLUSION

We depict the sociodemographic and dietary determinants of human gut mycobiome in middle-aged and elderly individuals, and further reveal that the gut mycobiome may be closely associated with the host metabolic health through regulating gut bacterial functions and metabolites.

Helicobacter pylori infection has a detrimental impact on the efficacy of cancer immunotherapies

OBJECTIVE

In this study, we determined whether Helicobacter pylori (H. pylori) infection dampens the efficacy of cancer immunotherapies.

DESIGN

Using mouse models, we evaluated whether immune checkpoint inhibitors or vaccine-based immunotherapies are effective in reducing tumour volumes of H. pylori-infected mice. In humans, we evaluated the correlation between H. pylori seropositivity and the efficacy of the programmed cell death protein 1 (PD-1) blockade therapy in patients with non-small-cell lung cancer (NSCLC).

RESULTS

In mice engrafted with MC38 colon adenocarcinoma or B16-OVA melanoma cells, the tumour volumes of non-infected mice undergoing anticytotoxic T-lymphocyte-associated protein 4 and/or programmed death ligand 1 or anti-cancer vaccine treatments were significantly smaller than those of infected mice. We observed a decreased number and activation status of tumour-specific CD8⁺ T cells in the tumours of infected mice treated with cancer immunotherapies independent of the gut microbiome composition. Additionally, by performing an in vitro co-culture assay, we observed that dendritic cells of infected mice promote lower tumour-specific CD8⁺ T cell proliferation. We performed retrospective human clinical studies in two independent cohorts. In the Dijon cohort, H. pylori seropositivity was found to be associated with a decreased NSCLC patient survival on anti-PD-1 therapy. The survival median for H. pylori seropositive patients was 6.7 months compared with 15.4 months for seronegative patients (p=0.001). Additionally, in the Montreal cohort, H. pylori seropositivity was found to be associated with an apparent decrease of NSCLC patient progression-free survival on anti-PD-1 therapy.

CONCLUSION

Our study unveils for the first time that the stomach microbiota affects the response to cancer immunotherapies and that H. pylori serology would be a powerful tool to personalize cancer immunotherapy treatment.

Unusual oral presentation of acyclovir-resistant herpes simplex in an allogeneic haematopoietic stem cell transplant recipient

The early engraftment phase of allogeneic haematopoietic stem cell transplantation can be associated with a number of oromucosal infective complications. While the routine use of prophylactic acyclovir has reduced the incidence of herpes simplex virus (HSV) reactivation, there is an increasing prevalence of acyclovir resistance within this cohort of patients. The authors present a case of acyclovir-resistant HSV reactivation in a 26-year-old woman 7 days post T-deplete sibling allograft on a background of combined cyclophosphamide and total body irradiation myeloablative conditioning, successfully treated with foscarnet and cidofovir therapy and discuss the differential diagnoses for early/late engraftment oral disease.

Digoxin targets low density lipoprotein receptor-related protein 4 and protects against osteoarthritis

OBJECTIVES

Dysregulated chondrocyte metabolism is closely associated with the pathogenesis of osteoarthritis (OA). Suppressing chondrocyte catabolism to restore cartilage homeostasis has been extensively explored, whereas far less effort has been invested toward enhancing chondrocyte anabolism. This study aimed to repurpose clinically approved drugs as potential stimulators of chondrocyte anabolism in treating OA.

METHODS

Screening of a Food and Drug Administration-approved drug library; Assays for examining the chondroprotective effects of digoxin in vitro; Assays for defining the therapeutic effects of digoxin using a surgically-induced OA model; A propensity-score matched cohort study using The Health Improvement Network to examine the relationship between digoxin use and the risk of joint OA-associated replacement among patients with atrial fibrillation; identification and characterisation of the binding of digoxin to low-density lipoprotein receptor-related protein 4 (LRP4); various assays, including use of CRISPR-Cas9 genome editing to delete LRP4 in human chondrocytes, for examining the dependence on LRP4 of digoxin regulation of chondrocytes.

RESULTS

Serial screenings led to the identification of ouabain and digoxin as stimulators of chondrocyte differentiation and anabolism. Ouabain and digoxin protected against OA and relieved OA-associated pain. The cohort study of 56 794 patients revealed that digoxin use was associated with reduced risk of OA-associated joint replacement. LRP4 was isolated as a novel target of digoxin, and deletion of LRP4 abolished digoxin's regulations of chondrocytes.

CONCLUSIONS

These findings not only provide new insights into the understanding of digoxin's chondroprotective action and underlying mechanisms, but also present new evidence for repurposing digoxin for OA.

Smoking associates with increased BAFF and decreased interferon-γ levels in patients with systemic lupus erythematosus

Objective

In SLE, smoking increases the burden of cutaneous disease and organ damage, and leads to premature mortality. However, the effect of smoking on disease manifestations and cytokine levels of patients with SLE is unclear. This study compared characteristics of patients with SLE across smoking status, and determined the association of smoking with serum cytokine levels.

Method

A cross-sectional study of patients with SLE (n=99) during a research visit in which smoking status was ascertained. Smoking status was compared across classification criteria (American College of Rheumatology Classification Criteria for SLE (ACR97)), disease activity (SLE Disease Activity Index), autoantibody levels, accrued damage (Systemic Lupus International Collaborating Clinics/ACR Damage Index), and circulating concentrations of serum interferon-gamma (IFN-γ), interleukin (IL)-1β, IL-4, IL-6, IL-10, IL-12, IL-17, B cell-activating factor (BAFF), tumour necrosis factor-alpha, transforming growth factor beta 1 (TGF-β1), macrophage inflammatory protein 1 alpha (MIP-1α), MIP-1β and monocyte chemoattractant protein 1. Linear regression models determined the association between smoking and cytokine levels, adjusting for age and sex, clinical characteristics (model 1), and anti-inflammatory (IL-4, IL-10 and TGF- β1) and regulatory (IL-1β) cytokines (model 2).

Results

Among patients with SLE (97.9% ANA+; mean 48.48 years old; 86.9% female; mean 10 years of disease duration), 35.4% (n=35 of 99) were smoking (an average of 7 cigarettes/day for 24 years). Smokers had increased odds of prevalent ACR97 malar rash (OR 3.40, 95% CI 1.23 to 9.34) and mucosal ulcers (OR 3.31, 95% CI 1.36 to 8.05). Smokers had more arthritis (OR 3.19, 95% CI 1.19 to 8.60), migraine (OR 2.82, 95% CI 1.07 to 7.44), Raynaud’s phenomenon (OR 5.15, 95% CI 1.95 to 13.56) and increased non-steroidal anti-inflammatory drug use (OR 6.88, 95% CI 1.99 to 23.72). Smoking associated with 27% increased BAFF levels (95% CI 6% to 48%) and 42% decreased IFN-γ levels (95% CI −79% to −5%) in model 2.

Conclusion

In patients with SLE, smoking independently associated with increased BAFF and decreased IFN-γ levels, and an increased frequency of arthritis, migraine and Raynaud’s phenomenon. Smoking cessation is advisable to reduce systemic inflammation, reduce disease activity and improve host defence.

Effect of aspirin on HIV disease progression among HIV-infected individuals initiating antiretroviral therapy: study protocol for a randomised controlled trial

INTRODUCTION

An increase in cardiovascular disease (CVD) among people living with HIV infection is linked to platelet and immune activation, a phenomenon unabolished by antiretroviral (ARV) drugs alone. In small studies, aspirin (acetylsalicylic acid [ASA]) has been shown to control immune activation, increase CD4+ count, halt HIV disease progression and reduce HIV viral load (HVL). We present a protocol for a larger ongoing randomised placebo controlled trial on the effect of an addition of ASA to ARV drugs on HIV disease progression.

METHODS AND ANALYSIS

A single-centre phase IIA double-blind, parallel-group randomised controlled trial intends to recruit 454 consenting ARV drug-naïve, HIV-infected adults initiating ART. Participants are randomised in blocks of 10 in a 1:1 ratio to receive, in addition to ARV drugs, 75 mg ASA or placebo for 6 months. The primary outcome is the proportion of participants attaining HVL of <50 copies/mL by 8, 12 and 24 weeks. Secondary outcomes include proportions of participants with HVL of >1000 copies/mL at week 24, attaining a >30% rise of CD4 count from baseline value at week 12, experiencing adverse events, with normal levels of biomarkers of platelet and immune activation at weeks 12 and 24 and rates of morbidity and all-cause mortality. Intention-to-treat analysis will be done for all study outcomes.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from institutional and national ethics review committees. Findings will be submitted to peer-reviewed journals and presented in scientific conferences.

TRIAL REGISTRATION NUMBER

PACTR202003522049711.

Endogenous HLA-DQ8αβ programs superantigens (SEG/SEI) to silence toxicity and unleash a tumoricidal network with long-term melanoma survival

Background

As the most powerful T cell agonists known, superantigens (SAgs) have enormous potential for cancer immunotherapy. Their development has languished due to high incidence (60%–80%) of seroreactive neutralizing antibodies in humans and tumor necrosis factor-α (TNFα)-mediated cardiopulmonary toxicity. Such toxicity has narrowed their therapeutic index while neutralizing antibodies have nullified their therapeutic effects.

Methods

Female HLA-DQ8 (DQA*0301/DQB*0302) tg mice expressing the human major histocompatibility complex II (MHCII) HLA-DQ8 allele on a high proportion of PBL, spleen and lymph node cells were used. In the established tumor model, staphylococcal enterotoxin G and staphylococcal enterotoxin I (SEG/ SEI) (50 µg each) were injected on days 6 and 9 following tumor inoculation. Lymphoid, myeloid cells and tumor cell digests from tumor tissue were assayed using flow cytometry or quantitated using a cytometric bead array. Tumor density, necrotic and viable areas were quantitated using the ImageJ software.

Results

In a discovery-driven effort to address these problems we introduce a heretofore unrecognized binary complex comprizing SEG/SEI SAgs linked to the endogenous human MHCII HLA-DQ8 allele in humanized mice. By contrast to staphylococcal enterotoxin A (SEA) and staphylococcal enterotoxin B (SEB) deployed previously in clinical trials, SEG and SEI does not exhibit neutralizing antibodies in humans or TNFα-mediated toxicity in humanized HLA-DQ8 mice. In the latter model wherein SAg behavior is known to be ‘human-like’, SEG/SEI induced a powerful tumoricidal response and long-term survival against established melanoma in 82% of mice. Other SAgs deployed in the same model displayed toxic shock. Initially, HLA-DQ8 mediated melanoma antigen priming, after which SEG/SEI unleashed a broad CD4+ and CD8+ antitumor network marked by expansion of melanoma reactive T cells and interferon-γ (IFNy) in the tumor microenvironment (TME). SEG/SEI further initiated chemotactic recruitment of tumor reactive T cells to the TME converting the tumor from ‘cold’ to a ‘hot’. Long-term survivors displayed remarkable resistance to parental tumor rechallenge along with the appearance of tumor specific memory and tumor reactive T memory cells.

Conclusions

Collectively, these findings show for the first time that the SEG/SEI-(HLA-DQ8) empowers priming, expansion and recruitment of a population of tumor reactive T cells culminating in tumor specific memory and long-term survival devoid of toxicity. These properties distinguish SEG/SEI from other SAgs used previously in human tumor immunotherapy. Consolidation of these principles within the SEG/SEI-(HLA-DQ8) complex constitutes a conceptually new therapeutic weapon with compelling translational potential.

Pattern Recognition Proteins: First Line of Defense Against Coronaviruses

The rapid outbreak of COVID-19 caused by the novel coronavirus SARS-CoV-2 in Wuhan, China, has become a worldwide pandemic affecting almost 204 million people and causing more than 4.3 million deaths as of August 11 2021. This pandemic has placed a substantial burden on the global healthcare system and the global economy. Availability of novel prophylactic and therapeutic approaches are crucially needed to prevent development of severe disease leading to major complications both acutely and chronically. The success in fighting this virus results from three main achievements: (a) Direct killing of the SARS-CoV-2 virus; (b) Development of a specific vaccine, and (c) Enhancement of the host's immune system. A fundamental necessity to win the battle against the virus involves a better understanding of the host's innate and adaptive immune response to the virus. Although the role of the adaptive immune response is directly involved in the generation of a vaccine, the role of innate immunity on RNA viruses in general, and coronaviruses in particular, is mostly unknown. In this review, we will consider the structure of RNA viruses, mainly coronaviruses, and their capacity to affect the lungs and the cardiovascular system. We will also consider the effects of the pattern recognition protein (PRP) trident composed by (a) Surfactant proteins A and D, mannose-binding lectin (MBL) and complement component 1q (C1q), (b) C-reactive protein, and (c) Innate and adaptive IgM antibodies, upon clearance of viral particles and apoptotic cells in lungs and atherosclerotic lesions. We emphasize on the role of pattern recognition protein immune therapies as a combination treatment to prevent development of severe respiratory syndrome and to reduce pulmonary and cardiovascular complications in patients with SARS-CoV-2 and summarize the need of a combined therapeutic approach that takes into account all aspects of immunity against SARS-CoV-2 virus and COVID-19 disease to allow mankind to beat this pandemic killer.

Effects of ibuprofen on gene expression in chondrocytes from patients with osteoarthritis as determined by RNA-Seq

Non-steroidal anti-inflammatory drugs are a widely used symptomatic treatment in osteoarthritis (OA), but their effects on cartilage remain controversial. We studied the effects of ibuprofen on gene expression in chondrocytes from patients with OA using RNA-Seq. Chondrocytes were isolated from cartilage samples of patients with OA undergoing knee replacement surgery, cultured with ibuprofen, and total mRNA was sequenced. Differentially expressed genes were identified with edgeR using pairwise comparisons. Functional analysis was performed using ingenuity pathway analysis (IPA). Ibuprofen did not induce statistically significant changes in chondrocyte transcriptome when the cells were cultured in the absence of added cytokines. In inflammatory conditions (when the cells were exposed to the OA-related cytokine interleukin (IL)-1β), 51 genes were upregulated and 42 downregulated by ibuprofen with fold change >1.5 in either direction. The upregulated genes included anti-inflammatory factors and genes associated with cell adhesion, while several mediators of inflammation were among the downregulated genes. IPA analysis revealed ibuprofen having modulating effects on inflammation-related pathways such as integrin, IL-8, ERK/MAPK and cAMP-mediated signalling pathways. In conclusion, the effects of ibuprofen on primary OA chondrocyte transcriptome appear to be neutral in normal conditions, but ibuprofen may shift chondrocyte transcriptome towards anti-inflammatory phenotype in inflammatory environments.

Advances in point-of-care testing for cardiovascular diseases

Point-of-care testing (POCT) is a specific format of diagnostic testing that is conducted without accompanying infrastructure or sophisticated instrumentation. Traditionally, such rapid sample-to-answer assays provide inferior analytical performances to their laboratory counterparts when measuring cardiac biomarkers. Hence, their potentially broad applicability is somewhat bound by their inability to detect clinically relevant concentrations of cardiac troponin (cTn) in the early stages of myocardial injury. However, the continuous refinement of biorecognition elements, the optimization of detection techniques, and the fabrication of tailored fluid handling systems to manage the sensing process has stimulated the production of commercial assays that can support accelerated diagnostic pathways. This review will present the latest commercial POC assays and examine their impact on clinical decision-making. The individual elements that constitute POC assays will be explored, with an emphasis on aspects that contribute to economically feasible and highly sensitive assays. Furthermore, the prospect of POCT imparting a greater influence on early interventions for medium to high-risk individuals and the potential to re-shape the paradigm of cardiovascular risk assessments will be discussed.

Homocitrullination of lysine residues mediated by myeloid-derived suppressor cells in the tumor environment is a target for cancer immunotherapy

Background

Homocitrullination is the post-translational modification of lysine that is recognized by T cells.

Methods

This study identified homocitrullinated peptides from aldolase, enolase, cytokeratin and binding immunoglobulin protein and used human leukocyte antigen (HLA) transgenic mice to assess immunogenicity by enzyme-linked immunosorbent spot assay. Vaccine efficacy was assessed in tumor therapy studies using HLA-matched B16 melanoma expressing constitutive or interferon γ (IFNγ)-inducible major histocompatibility complex class II (MHC-II) as represented by most human tumors. To determine the mechanism behind the therapy, immune cell infiltrates were analyzed using flow cytometry and therapy studies in the presence of myeloperoxidase (MPO) inhibitor and T-cell depletion performed. We assessed the T-cell repertoire to homocitrullinated peptides in patients with cancer and healthy donors using flow cytometry.

Results

Homocitrulline (Hcit) peptide vaccination stimulated strong CD4 T-cell responses and induced significant antitumor therapy in an established tumor model. The antitumor response was dependent on CD4 T cells and the effect was driven mainly via direct tumor recognition, as responses were only observed if the tumors were induced to express MHC-II. In vitro proliferation assays show that healthy donors and patients with cancer have an oligoclonal CD4 T-cell repertoire recognizing homocitrullinated peptides. Inhibition of cyanate generation, which mediates homocitrullination, by MPO inhibition reduced tumor therapy by the vaccine induced T cells (p=0.0018). Analysis of the tumor microenvironment (TME) suggested that myeloid-derived suppressor cells (MDSCs) were a potential source of MPO. The selected B16 melanoma model showed MDSC infiltration and was appropriate to see if the Hcit vaccine could overcome the immunosuppression associated with MDSCs. The vaccine was very effective (90% survival) as the induced CD4 T cells directly targeted the homocitrullinated tumor and likely reversed the immunosuppressive environment.

Conclusion

We propose that MPO, potentially produced by MDSCs, catalyzes the buildup of cyanate in the TME which diffuses into tumor cells causing homocitrullination of cytoplasmic proteins which are degraded and, in the presence of IFNγ, presented by MHC-II for direct CD4 T-cell recognition. Homocitrullinated proteins are a new target for cancer vaccines and may be particularly effective against tumors containing high levels of MPO expressing MDSCs.

Diagnostic efficacy of serum and urinary netrin-1 in the early detection of diabetic nephropathy

This study aimed to assess the diagnostic value of serum and urinary netrin-1 in patients with type 2 diabetes mellitus (T2DM) at different stages of diabetic nephropathy (DN) and to compare its efficacy of estimation in serum with that in the urine. This study was carried out on 135 patients with T2DM and 45 healthy subjects. The patients with diabetes were divided according to urinary albumin creatinine ratio (UACR) into: T2DM with normoalbuminuria, incipient DN with microalbuminuria, and overt DN with macroalbuminuria groups. Serum and urinary levels of netrin-1 were measured by ELISA. The mean levels of serum and urinary netrin-1 were significantly higher in the microalbuminuric and macroalbuminuric patients with DN than those in the normoalbuminuric patients with T2DM, with the highest values detected in macroalbuminuric patients with DN. Urinary netrin-1 level was significantly higher in the normoalbuminuric T2DM group than control group, whereas no significant difference existed regarding serum netrin-1 level. In T2DM groups, the urinary and serum netrin-1 correlated with each other and were independently related to fasting blood glucose, UACR, and estimated glomerular filtration rate. Receiver operating characteristic curve analysis showed that the area under the curve of urinary netrin-1 was 0.916 which is significantly higher than that of serum netrin-1 (0.812) for the detection of incipient DN and reached 0.938 on coestimation of both urinary and serum netrin-1. In conclusion, netrin-1 is a potential diagnostic marker for early detection of DN with its estimation in urine has higher accuracy than that of serum.

Increased serum nesfatin-1 levels in patients with inflammatory bowel diseases

BACKGROUND

Adipokines are adipose tissue-derived secreted molecules that can exert anti-inflammatory or proinflammatory activities. Altered expression of adipokines has been described in various inflammatory diseases, including inflammatory bowel diseases (IBDs) such as Crohn's disease (CD) and ulcerative colitis (UC). Little is known about nesfatin-1, a recently identified adipokine, in IBD. The aim of this study was to investigate serum nesfatin-1 levels in patients with IBD.

METHODS

This study included a total of 52 adult individuals (17 patients with CD, 18 patients with UC and 17 healthy volunteers) with similar age and body mass index. Serum nesfatin-1 levels were measured by ELISA in healthy individuals and patients with IBD in their active and remission periods. Blood inflammation markers including C reactive protein (CRP), erythrocyte sedimentation (ESR) and white cell count (WCC) were also measured in patients.

RESULTS

We found significantly elevated levels of serum nesfatin-1 in the active disease period in both patients with CD (p=0.00003) and patients with UC (p=0.00001), compared with healthy individuals. Serum nesfatin-1 levels moderately decreased in the remission period; however, they were still significantly higher than that of healthy individuals. Receiver operating characteristic curve analyses indicated serum nesfatin-1 with an excellent diagnostic value for IBD. Finally, patients had significantly high CRP, ESR and WCC in the active IBD; however, we found the nesfatin-1 strongly correlated only with ESR in the active CD.

CONCLUSION

This is the first study investigating the circulating levels of nesfatin-1 in patients with IBD. Serum nesfatin-1 may serve as an additional inflammatory marker for diagnosis of IBD in affected individuals.

Therapeutic Lowering of C-Reactive Protein

In the blood of healthy individuals C-reactive protein (CRP) is typically quite scarce, whereas its blood concentration can rise robustly and rapidly in response to tissue damage and inflammation associated with trauma and infectious and non-infectious diseases. Consequently, CRP plasma or serum levels are routinely monitored in inpatients to gauge the severity of their initial illness and injury and their subsequent response to therapy and return to health. Its clinical utility as a faithful barometer of inflammation notwithstanding, it is often wrongly concluded that the biological actions of CRP (whatever they may be) are manifested only when blood CRP is elevated. In fact over the last decades, studies done in humans and animals (e.g. human CRP transgenic and CRP knockout mice) have shown that CRP is an important mediator of biological activities even in the absence of significant blood elevation, i.e. even at baseline levels. In this review we briefly recap the history of CRP, including a description of its discovery, early clinical use, and biosynthesis at baseline and during the acute phase response. Next we overview evidence that we and others have generated using animal models of arthritis, neointimal hyperplasia, and acute kidney injury that baseline CRP exerts important biological effects. In closing we discuss the possibility that therapeutic lowering of baseline CRP might be a useful way to treat certain diseases, including cancer.

TDP-43-specific Autoantibody Decline in Patients With Amyotrophic Lateral Sclerosis

OBJECTIVE

We hypothesize alterations in the quality and quantity of anti-43-kDa TAR DNA-binding protein (TDP-43) naturally occurring autoantibodies (NAbs) in patients with amyotrophic lateral sclerosis (ALS); therefore, we assessed relative binding properties of anti-TDP-43 NAbs composite in plasma from patients with ALS in comparison with healthy individuals.

METHODS

ELISA competition assay was used to explore the apparent avidity/affinity of anti-TDP-43 NAbs in plasma from 51 normal controls and 30 patients with ALS. Furthermore, the relative levels of anti-TDP-43 NAbs within the immunoglobulin (Ig) classes of IgG (isotype IgG1-4) and IgMs were measured using classical indirect ELISA. The occurring results were hereafter correlated with the measures of disease duration and disease progression.

RESULTS

High-avidity/affinity anti-TDP-43 NAbs levels were significantly reduced in plasma samples from patients with ALS. In addition, a significant decrease in relative levels of anti-TDP-43 IgG3 and IgM NAbs and a significant increase in anti-TDP-43 IgG4 NAbs were observed in ALS plasma vs controls. Furthermore, a decrease in global IgM and an increase in IgG4 levels were observed in ALS. These aberrations of humoral immunity correlated with disease duration, but did not correlate with ALS Functional Rating Scale-Revised scores.

CONCLUSIONS

Our results may suggest TDP-43-specific immune aberrations in patients with ALS. The skewed immune profiles observed in patients with ALS could indicate a deficiency in the clearance capacity and/or blocking of TDP-43 transmission and propagation. The decrease in levels of high affinity/avidity anti-TDP-43 NAbs and IgMs correlates with disease progression and may be disease predictors.

Treatment of Pneumococcal Infection by Using Engineered Human C-Reactive Protein in a Mouse Model

C-reactive protein (CRP) binds to several species of bacterial pathogens including Streptococcus pneumoniae. Experiments in mice have revealed that one of the functions of CRP is to protect against pneumococcal infection by binding to pneumococci and activating the complement system. For protection, however, CRP must be injected into mice within a few hours of administering pneumococci, that is, CRP is protective against early-stage infection but not against late-stage infection. It is assumed that CRP cannot protect if pneumococci got time to recruit complement inhibitor factor H on their surface to become complement attack-resistant. Since the conformation of CRP is altered under inflammatory conditions and altered CRP binds to immobilized factor H also, we hypothesized that in order to protect against late-stage infection, CRP needed to change its structure and that was not happening in mice. Accordingly, we engineered CRP molecules (E-CRP) which bind to factor H on pneumococci but do not bind to factor H on any host cell in the blood. We found that E-CRP, in cooperation with wild-type CRP, was protective regardless of the timing of administering E-CRP into mice. We conclude that CRP acts via two different conformations to execute its anti-pneumococcal function and a model for the mechanism of action of CRP is proposed. These results suggest that pre-modified CRP, such as E-CRP, is therapeutically beneficial to decrease bacteremia in pneumococcal infection. Our findings may also have implications for infections with antibiotic-resistant pneumococcal strains and for infections with other bacterial species that use host proteins to evade complement-mediated killing.

LncRNA TTTY15 knockdown alleviates H2O2-stimulated myocardial cell injury by regulating the miR-98-5p/CRP pathway

Acute myocardial infarction (AMI) can lead to myocardial injury, and long non-coding RNA (lncRNA) has been found to play an important regulatory role in the process of myocardial injury. However, the role and potential mechanisms of lncRNA testis-specific transcript Y-linked 15 (TTTY15) in AMI-induced myocardial injury has not been fully elucidated. Hydrogen peroxide (H₂O₂)-induced AMI cell model was built and AMI mice model were constructed. Relative expression levels of TTTY15, miR-98-5p and C-reactive protein (CRP) were determined by quantitative real-time PCR (qRT-PCR). Cell counting kit 8 (CCK8) assay, flow cytometry and enzyme-linked immunosorbent assay (ELISA) were employed to assess cell viability, apoptosis, inflammatory response and oxidative stress. Western blot (WB) analysis was used to assess the protein expression levels. The mechanism of TTTY15 was confirmed by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Our results revealed that TTTY15 was upregulated and miR-98-5p was downregulated in AMI patients and H₂O₂-stimulated myocardial cells. Knockdown of TTTY15 could alleviate H₂O₂-stimulated myocardial cell injury in vitro and AMI progression in vivo. Bioinformatics analysis and the rescue experiments confirmed that TTTY15 positively regulated H₂O₂-induced myocardial cell injury via regulating CRP by sponging miR-98-5p. Our research proposed that lncRNA TTTY15 promoted myocardial cell injury by regulating the miR-98-5p/CRP axis, suggesting that TTTY15 might be a potential target for alleviating AMI-caused myocardial cell injury.

Complement Activation by C-Reactive Protein Is Critical for Protection of Mice Against Pneumococcal Infection

C-reactive protein (CRP), a component of the innate immune system, is an antipneumococcal plasma protein. Human CRP has been shown to protect mice against infection with lethal doses of Streptococcus pneumoniae by decreasing bacteremia. in vitro, CRP binds to phosphocholine-containing substances, such as pneumococcal C-polysaccharide, in a Ca²⁺-dependent manner. Phosphocholine-complexed human CRP activates the complement system in both human and murine sera. The mechanism of antipneumococcal action of CRP in vivo, however, has not been defined yet. In this study, we tested a decades-old hypothesis that the complement-activating property of phosphocholine-complexed CRP contributes to protection of mice against pneumococcal infection. Our approach was to investigate a CRP mutant, incapable of activating murine complement, in mouse protection experiments. We employed site-directed mutagenesis of CRP, guided by its three-dimensional structure, and identified a mutant H38R which, unlike wild-type CRP, did not activate complement in murine serum. Substitution of His³⁸ with Arg in CRP did not affect the pentameric structure of CRP, did not affect the binding of CRP to pneumococci, and did not decrease the stability of CRP in mouse circulation. Employing a murine model of pneumococcal infection, we found that passively administered H38R CRP failed to protect mice against infection. Infected mice injected with H38R CRP showed no reduction in bacteremia and did not survive longer, as opposed to infected mice treated with wild-type CRP. Thus, the hypothesis that complement activation by phosphocholine-complexed CRP is an antipneumococcal effector function was supported. We can conclude now that complement activation by phosphocholine-complexed CRP is indeed essential for CRP-mediated protection of mice against pneumococcal infection.

Conformationally Altered C-Reactive Protein Capable of Binding to Atherogenic Lipoproteins Reduces Atherosclerosis

The aim of this study was to test the hypothesis that C-reactive protein (CRP) protects against the development of atherosclerosis and that a conformational alteration of wild-type CRP is necessary for CRP to do so. Atherosclerosis is an inflammatory cardiovascular disease and CRP is a plasma protein produced by the liver in inflammatory states. The co-localization of CRP and low-density lipoproteins (LDL) at atherosclerotic lesions suggests a possible role of CRP in atherosclerosis. CRP binds to phosphocholine-containing molecules but does not interact with LDL unless the phosphocholine groups in LDL are exposed. However, CRP can bind to LDL, without the exposure of phosphocholine groups, if the native conformation of CRP is altered. Previously, we reported a CRP mutant, F66A/T76Y/E81A, generated by site-directed mutagenesis, that did not bind to phosphocholine. Unexpectedly, this mutant CRP, without any more conformational alteration, was found to bind to atherogenic LDL. We hypothesized that this CRP mutant, unlike wild-type CRP, could be anti-atherosclerotic and, accordingly, the effects of mutant CRP on atherosclerosis in atherosclerosis-prone LDL receptor-deficient mice were evaluated. Administration of mutant CRP into mice every other day for a few weeks slowed the progression of atherosclerosis. The size of atherosclerotic lesions in the aorta of mice treated with mutant CRP for 9 weeks was ~40% smaller than the lesions in the aorta of untreated mice. Thus, mutant CRP conferred protection against atherosclerosis, providing a proof of concept that a local inflammation-induced structural change in wild-type CRP is a prerequisite for CRP to control the development of atherosclerosis.

Lower estimated bone strength and impaired bone microarchitecture in children with type 1 diabetes

INTRODUCTION

Patients with type 1 diabetes has an increased risk of fracture. We wished to evaluate estimated bone strength in children and adolescents with type 1 diabetes and assess peripheral bone geometry, volumetric bone mineral density (vBMD) and microarchitecture.

RESEARCH DESIGN AND METHODS

In a cross-sectional study, high-resolution peripheral quantitative CT (HR-pQCT) was performed of the radius and tibia in 84 children with type 1 diabetes and 55 healthy sibling controls. Estimated bone strength was assessed using a microfinite element analysis solver. Multivariate regression analyses were performed adjusting for age, sex, height and body mass index.

RESULTS

The median age was 13.0 years in the diabetes group vs 11.5 years in healthy sibling controls. The median (range) diabetes duration was 4.2 (0.4-15.9) years; median (range) latest year Hb1Ac was 7.8 (5.9-11.8) % (61.8 (41-106) mmol/mol). In adjusted analyses, patients with type 1 diabetes had reduced estimated bone strength in both radius, β -390.6 (-621.2 to -159.9) N, p=0.001, and tibia, β -891.9 (-1321 to -462.9) N, p<0.001. In the radius and tibia, children with type 1 diabetes had reduced cortical area, trabecular vBMD, trabecular number and trabecular bone volume fraction and increased trabecular inhomogeneity, adjusted p<0.05 for all. Latest year HbA1c was negatively correlated with bone microarchitecture (radius and tibia), trabecular vBMD and estimated bone strength (tibia).

CONCLUSION

Children with type 1 diabetes had reduced estimated bone strength. This reduced bone strength could partly be explained by reduced trabecular bone mineral density, adverse microarchitecture and reduced cortical area. We also found increasing latest year HbA1c to be associated with several adverse changes in bone parameters. HR-pQCT holds potential to identify early adverse bone changes and to explain the increased fracture risk in young patients with type 1 diabetes.

Treatment strategies for asymptomatic carotid artery stenosis in the era of lipid-lowering drugs: protocol for a systematic review and network meta-analysis

INTRODUCTION

Carotid endarterectomy (CEA), carotid artery stenting (CAS) and best medical therapy (BMT) are the major treatments used for significant asymptomatic carotid artery stenosis (ACAS, ≥50%). However, the widespread use of lipid-lowering drugs in this century has improved BMT outcomes. This study aims to compare the treatment efficacy of current BMT, CEA+BMT and CAS+BMT in patients with significant ACAS.

METHODS AND ANALYSIS

This protocol was designed based on the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. Publication time for studies will be set from 1 January 2000 to 1 June 2020. We will search three databases: PubMed, EMBASE and The Cochrane Library. Suitable randomised controlled studies will be screened. The primary outcomes will include short-term and long-term mortality, stroke and myocardial infarction. OR and HR for dichotomous data and time-to-event data with 95% CIs will be calculated. Treatment effects among different therapies will be ranked according to the surface under the cumulative ranking curve and mean rank. A comprehensive evaluation of the risk of bias, heterogeneity and transitivity will be performed before data synthesis. Consistency and evidence quality will also be assessed.

ETHICS AND DISSEMINATION

There will be no need for ethics approval as this systematic review is a summary and analysis of existing literature. Final results may be presented in international conferences or a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42019138942.

Combined therapy of photobiomodulation and adipose-derived stem cells synergistically improve healing in an ischemic, infected and delayed healing wound model in rats with type 1 diabetes mellitus

OBJECTIVE

We assessed the therapeutic effects of photobiomodulation (PBM) and adipose-derived stem cell (ADS) treatments individually and together on the maturation step of repairing of a delayed healing wound model in rats with type 1 diabetes mellitus (DM1).

RESEARCH DESIGN AND METHODS

We randomly assigned 24 rats with DM1 to four groups (n=6 per group). Group 1 was the control (placebo) group. In group 2, allograft human ADSs were transplanted. Group 3 was subjected to PBM (wavelength: 890 nm, peak power output: 80 W, pulse frequency: 80 Hz, pulsed duration: 180 ns, duration of exposure for each point: 200 s, power density: 0.001 W/cm², energy density: 0.2 J/cm²) immediately after surgery, which continued for 6 days per week for 16 days. Group 4 received both the human ADS and PBM. In addition, we inflicted an ischemic, delayed healing, and infected wound simulation in all of the rats. The wounds were infected with methicillin-resistant Staphylococcus aureus (MRSA).

RESULTS

All three treatment regimens significantly decreased the amount of microbial flora, significantly increased wound strength and significantly modulated inflammatory response and significantly increased angiogenesis on day 16. Microbiological analysis showed that PBM+ADS was significantly better than PBM and ADS alone. In terms of wound closure rate and angiogenesis, PBM+ADS was significantly better than the PBM, ADS and control groups.

CONCLUSIONS

Combination therapy of PBM+ADS is more effective that either PBM or ADS in stimulating skin injury repair, and modulating inflammatory response in an MRSA-infected wound model of rats with DM1.

Zebrafish C-reactive protein isoforms inhibit SVCV replication by blocking autophagy through interactions with cell membrane cholesterol

In the present work, the mechanisms involved in the recently reported antiviral activity of zebrafish C-reactive protein-like protein (CRP1-7) against the spring viraemia of carp rhabdovirus (SVCV) in fish are explored. The results neither indicate blocking of the attachment or the binding step of the viral replication cycle nor suggest the direct inhibition of G protein fusion activity or the stimulation of the host’s interferon system. However, an antiviral state in the host is induced. Further results showed that the antiviral protection conferred by CRP1-7 was mainly due to the inhibition of autophagic processes. Thus, given the high affinity of CRPs for cholesterol and the recently described influence of the cholesterol balance in lipid rafts on autophagy, both methyl-β-cyclodextrin (a cholesterol-complexing agent) and 25-hydroxycholesterol (a cholesterol molecule with antiviral properties) were used to further describe CRP activity. All the tested compounds exerted antiviral activity by affecting autophagy in a similar manner. Further assays indicate that CRP reduces autophagy activity by initially disturbing the cholesterol ratios in the host cellular membranes, which in turn negatively affects the intracellular regulation of reactive oxygen species (ROS) and increases lysosomal pH as a consequence. Ultimately, here we propose that such pH changes exert an inhibitory direct effect on SVCV replication by disrupting the pH-dependent membrane-fusogenic ability of the viral glycoprotein G, which allows the release of the virus from endosomes into cytoplasm during its entry phase.

Monomeric C-reactive protein regulates fibronectin mediated monocyte adhesion

The acute phase reactant C-reactive protein (CRP) binds with high affinity to fibronectin (FN), but this binding occurs only at pH 6.5 or lower, and the binding is inhibited by calcium ions at physiological pH. Since CRP in the circulating blood exists in a calcium-binding form, the interaction between CRP and FN in vivo has been uncertain. CRP can undergo a conformational rearrangement in the absence of calcium or in the local microenvironment (e.g., acidic pH) of inflamed tissue to dissociate into monomeric CRP (mCRP). Therefore, we tested whether these discrepancies can be explained by the different isoforms and locations of CRP. Surface plasmon resonance and ELISA assays showed that mCRP binds with high affinity to FN, and the binding of mCRP to FN was unaffected by calcium or pH. Peptide competition assay, deletion mutant binding assay and protein docking analyse verified that the binding site of mCRP to FN is residues a.a.35-47. Furthermore, mCRP can significantly enhance the adhesion of monocytes to FN as well as upregulate the adhesion molecules expression on endothelial cell. Colocalization of mCRP with FN was observed in mice with DSS-induced colitis, whereas there was very little signal orcolocalization of CRP. These results provide in vitro and in vivo evidence that mCRP formed by local dissociation from circulating CRP is the major isoform that interacts with FN and regulates FN-mediated monocyte adhesion, which is involved in the pro-inflammatory process.

Functionality of C-Reactive Protein for Atheroprotection

C-reactive protein (CRP) is a pentameric molecule made up of identical monomers. CRP can be seen in three different forms: native pentameric CRP (native CRP), non-native pentameric CRP (non-native CRP), and monomeric CRP (mCRP). Both native and non-native CRP execute ligand-recognition functions for host defense. The fate of any pentameric CRP after binding to a ligand is dissociation into ligand-bound mCRP. If ligand-bound mCRP is proinflammatory, like free mCRP has been shown to be in vitro, then mCRP along with the bound ligand must be cleared from the site of inflammation. Once pentameric CRP is bound to atherogenic low-density lipoprotein (LDL), it reduces both formation of foam cells and proinflammatory effects of atherogenic LDL. A CRP mutant, that is non-native CRP, which readily binds to atherogenic LDL, has been found to be atheroprotective in a murine model of atherosclerosis. Thus, unlike statins, a drug that can lower only cholesterol levels but not CRP levels should be developed. Since non-native CRP has been shown to bind to all kinds of malformed proteins in general, it is possible that non-native CRP would be protective against all inflammatory states in which host proteins become pathogenic. If it is proven through experimentation employing transgenic mice that non-native CRP is beneficial for the host, then using a small-molecule compound to target CRP with the goal of changing the conformation of endogenous native CRP would be preferred over using recombinant non-native CRP as a biologic to treat diseases caused by pathogenic proteins such as oxidized LDL.

The Multiple Faces of C-Reactive Protein-Physiological and Pathophysiological Implications in Cardiovascular Disease

C-reactive protein (CRP) is an intriguing protein which plays a variety of roles in either physiological or pathophysiological states. For years it has been regarded merely as a useful biomarker of infection, tissue injury and inflammation, and it was only in the early 80s that the modified isoforms (mCRP) of native CRP (nCRP) appeared. It soon became clear that the roles of native CRP should be clearly discriminated from those of the modified form and so the impacts of both isoforms were divided to a certain degree between physiological and pathophysiological states. For decades, CRP has been regarded only as a hallmark of inflammation; however, it has since been recognised as a significant predictor of future episodes of cardiovascular disease, independent of other risk factors. The existence of modified CRP isoforms and their possible relevance to various pathophysiological conditions, suggested over thirty years ago, has prompted the search for structural and functional dissimilarities between the pentameric nCRP and monomeric mCRP isoforms. New attempts to identify the possible relevance between the diversity of structures and their opposing functions have initiated a new era of research on C-reactive protein. This review discusses the biochemical aspects of CRP physiology, emphasizing the supposed relevance between the structural biology of CRP isoforms and their differentiated physiological and pathophysiological roles.

Evolution of C-Reactive Protein

C-reactive protein (CRP) is an evolutionarily conserved protein. From arthropods to humans, CRP has been found in every organism where the presence of CRP has been sought. Human CRP is a pentamer made up of five identical subunits which binds to phosphocholine (PCh) in a Ca²⁺-dependent manner. In various species, we define a protein as CRP if it has any two of the following three characteristics: First, it is a cyclic oligomer of almost identical subunits of molecular weight 20–30 kDa. Second, it binds to PCh in a Ca²⁺-dependent manner. Third, it exhibits immunological cross-reactivity with human CRP. In the arthropod horseshoe crab, CRP is a constitutively expressed protein, while in humans, CRP is an acute phase plasma protein and a component of the acute phase response. As the nature of CRP gene expression evolved from a constitutively expressed protein in arthropods to an acute phase protein in humans, the definition of CRP became distinctive. In humans, CRP can be distinguished from other homologous proteins such as serum amyloid P, but this is not the case for most other vertebrates and invertebrates. Literature indicates that the binding ability of CRP to PCh is less relevant than its binding to other ligands. Human CRP displays structure-based ligand-binding specificities, but it is not known if that is true for invertebrate CRP. During evolution, changes in the intrachain disulfide and interchain disulfide bonds and changes in the glycosylation status of CRP may be responsible for different structure-function relationships of CRP in various species. More studies of invertebrate CRP are needed to understand the reasons behind such evolution of CRP. Also, CRP evolved as a component of and along with the development of the immune system. It is important to understand the biology of ancient CRP molecules because the knowledge could be useful for immunodeficient individuals.

Human host defence peptide LL37 and anti-cyclic citrullinated peptide antibody in early inflammatory arthritis

Objective

Antibodies to citrullinated peptides (anti-CCP) develop in individuals predisposed to rheumatoid arthritis (RA). Neutrophil extracellular traps are a major source of citrullinated antigens and the immunomodulatory host defence peptide LL-37. Vitamin D regulates LL-37 expression. This study assessed the associations of LL-37 and anti-CCP, vitamin D metabolites and vitamin D receptor (VDR) polymorphisms in early inflammatory arthritis (EIA).

Methods

Serum LL-37, 25-hydroxy-vitamin D (25OHvitD) and anti-CCP were measured by ELISA in treatment naïve EIA (n = 181). VDR single nucleotide polymorphisms (Fok1, Bsm1, Apa1, Taq1, Cdx-2) and HLADRB1 shared epitope (SE) alleles were detected by DNA amplification. Associations were tested in multivariable models. Median (25%, 75%) or percentiles are reported.

Results

Participants (70 % female, age 56 [45, 66] years, disease activity score [DAS28ESR3var] 3.7 [2.8, 4.8], 41 % anti-CCP positive, 68 % RA) had low serum 25OHvitD; 20.5 nmol/L (13.9, 29.0). In multivariable models, controlling for age, sex, SE, smoking and vitamin D deficiency, LL37 level (top quartile) associated with anti-CCP seropositivity (OR 22; 95% CI 4 to 104).

Conclusions

Levels of circulating LL-37 are associated with anti-CCP seropositivity. LL37 activity may be one mechanism linking infection and toxin exposure to anti-CCP generation.

Hyper-acidic fusion minipeptides escort the intrinsic antioxidative ability of the pattern recognition receptor CRP in non-animal organisms

C-reactive protein (CRP) is widely used as a biomarker of inflammation. It plays important roles in innate immunity response as a member of pattern recognition receptors, by binding oxidation-specific epitopes including some intermediates of lipid oxidative chain reaction. The inferred antioxidative ability of CRP was ever demonstrated by only few in vitro evidences, and needs to be clarified especially in vivo. Herein, we expressed human CRP in three representative non-animal organisms (Escherichia coli, Saccharomyces cerevisiae, and tobacco) inherently lacking the milieu for CRP signalling, and found CRP did possess an intrinsic antioxidative ability. Heterologous CRP could confer increased oxidative resistance in its recombinant E. coli and yeast cells and transgenic tobaccos. We also revealed a positive correlation between the antioxidative effect of CRP and its solubility. Only soluble CRP could exhibit distinct antioxidative activity, while the CRP aggregates might be instead toxic (probably pro-oxidative) to cells. Moreover, fusion with hyper-acidic minipeptides could remarkably improve CRP solubility, and meanwhile guarantee or enhance CRP antioxidative ability. These results not only provide a new insight for understanding the etiology of CRP-involved inflammations and diseases, and also endorse a potential of CRP biotechnological applications in developing new pharmaceutical therapies and improving plant oxidative resistance.

Structure-Function Relationships of C-Reactive Protein in Bacterial Infection

One host defense function of C-reactive protein (CRP) is to protect against Streptococcus pneumoniae infection as shown by experiments employing murine models of pneumococcal infection. The protective effect of CRP is due to reduction in bacteremia. There is a distinct relationship between the structure of CRP and its anti-pneumococcal function. CRP is functional in both native and non-native pentameric structural conformations. In the native conformation, CRP binds to pneumococci through the phosphocholine molecules present on the C-polysaccharide of the pneumococcus and the anti-pneumococcal function probably involves the known ability of ligand-complexed CRP to activate the complement system. In the native structure-function relationship, CRP is protective only when given to mice within a few hours of the administration of pneumococci. The non-native pentameric conformation of CRP is created when CRP is exposed to conditions mimicking inflammatory microenvironments, such as acidic pH and redox conditions. In the non-native conformation, CRP binds to immobilized complement inhibitor factor H in addition to being able to bind to phosphocholine. Recent data using CRP mutants suggest that the factor H-binding function of non-native CRP is beneficial: in the non-native structure-function relationship, CRP can be given to mice any time after the administration of pneumococci irrespective of whether the pneumococci became complement-resistant or not. In conclusion, while native CRP is protective only against early stage infection, non-native CRP is protective against both early stage and late stage infections. Because non-native CRP displays phosphocholine-independent anti-pneumococcal activity, it is quite possible that CRP functions as a general anti-bacterial molecule.

Targeting IL-17 attenuates hypoxia-induced pulmonary hypertension through downregulation of β-catenin

BACKGROUND

The role of interleukin 17 (IL-17) in hypoxic pulmonary hypertension (HPH) remains unclear. This study is designed to explore whether IL-17 is a potential target for HPH treatment.

METHODS

Clinic samples from the lung tissue and serum were obtained from qualified patients. Western blotting, immunohistochemistry and/or ELISA were used to measure the expression of relevant proteins. HPH models were established in C57BL/6 wild-type (WT) and IL-17 ^-/- mice and were treated with exogenous recombinant mouse IL-17 (rmIL-17) or an IL-17 neutralising antibody. Assays for cell proliferation, angiogenesis and adhesion were employed to analyse the behaviours of human pulmonary arterial endothelial cells (HPAECs). A non-contact Transwell coculture model was used to evaluate intercellular interactions.

RESULTS

Expression of IL-17 was increased in lung tissue of both patients with bronchiectasis/COPD-associated PH and HPH mouse model. Compared with WT mice, IL-17 ^-/- mice had attenuated HPH, whereas administration of rmIL-17 aggravated HPH. In vitro, recombinant human IL-17 (rhIL-17) promoted proliferation, angiogenesis and adhesion in HPAECs through upregulation of Wnt3a/β-catenin/CyclinD1 pathway, and siRNA-mediated knockdown of β-catenin almost completely reversed this IL-17-mediated phenomena. IL-17 promoted the proliferation but not the migration of human pulmonary arterial smooth muscle cells (HPASMCs) cocultured with HPAECs under both normoxia and hypoxia, but IL-17 had no direct effect on proliferation and migration of HPASMCs. Blockade of IL-17 with a neutralising antibody attenuated HPH in WT mice.

CONCLUSIONS

IL-17 contributes to the pathogenesis of HPH through upregulation of β-catenin expression. Targeting IL-17 might provide potential benefits for alternative therapeutic strategies for HPH.

Fatty acids promote fatty liver disease via the dysregulation of 3-mercaptopyruvate sulfurtransferase/hydrogen sulfide pathway

OBJECTIVE

Accumulation of free fatty acids (FFAs) in hepatocytes induces lipotoxicity, leading to non-alcoholic fatty liver disease (NAFLD). This study aimed to investigate the underlying mechanisms by which FFA contributes to the pathogenesis of NAFLD via the regulation of 3-mercaptopyruvate sulfurtransferase (MPST), a key enzyme that regulates endogenous hydrogen sulfide (H₂S) biosynthesis.

DESIGN

Hepatic MPST expression was evaluated in mice and patients with NAFLD. A variety of molecular approaches were used to study the effects of MPST regulation on hepatic steatosis in vivo and in vitro.

RESULTS

In vitro treatment of hepatocytes with FFAs upregulated MPST expression, which was partially dependent on NF-κB/p65. Hepatic MPST expression was markedly increased in high fat diet (HFD)-fed mice and patients with NAFLD. Partial knockdown of MPST via adenovirus delivery of MPST short hairpin RNA or heterozygous deletion of the Mpst gene significantly ameliorated hepatic steatosis in HFD-fed mice. Consistently, inhibition of MPST also reduced FFA-induced fat accumulation in L02 cells. Intriguingly, inhibition of MPST significantly enhanced rather than decreased H₂S production, whereas MPST overexpression markedly inhibited H₂S production. Co-immunoprecipitation experiments showed that MPST directly interacted with and negatively regulated cystathionine γ-lyase (CSE), a major source of H₂S production in the liver. Mechanistically, MPST promoted steatosis via inhibition of CSE/H₂S and subsequent upregulation of the sterol regulatory element-binding protein 1c pathway, C-Jun N-terminal kinase phosphorylation and hepatic oxidative stress.

CONCLUSIONS

FFAs upregulate hepatic expression of MPST and subsequently inhibit the CSE/H₂S pathway, leading to NAFLD. MPST may be a potential therapeutic target for NAFLD.

A multi-site coronary sampling study on CRP in non-STEMI: Novel insights into the inflammatory process in acute coronary syndromes

BACKGROUND AND AIMS

Inflammation has become a key element in cardiovascular disease, and recently, new anti-inflammatory interventions have shown promising results. In this context, CRP levels have been thoroughly studied in vitro and in animals, but studies in humans are scarce and insights into its release, site(s) of production and uptake are not uniform.

METHODS

We performed a biomarker study with multi-site sampling in the coronary circulation, in non-ST elevation MI (NSTEMI) patients with coronary angiography and right-sided catheterisation. Trans-lesional gradients were obtained by sampling distal to the culprit lesion, in patients with a suitable anatomy. To asses trans-cardiac gradients, blood was sampled from the systemic circulation, coronary sinus (CS) and great cardiac vein. Concentrations of CRP were measured with a high-sensitivity assay.

RESULTS

In 42 patients, a median systemic venous CRP concentration of 4.97 mg/L was observed. There was no evidence of a trans-lesional gradient (4.59 mg/L versus 4.56 mg/L, p = 0.278; n = 14). A significant decrease in CRP concentration was observed between systemic arterial and CS samples (4.88 mg/L versus 4.44 mg/L; p < 0.001; n = 42). This trans-cardiac gradient was irrespective of time of presentation, infarct size and culprit lesion location. The gradient was not only driven by blood that ran through the injured myocardium, but also by lower CRP concentrations in the coronary veins that drain non-infarcted myocardium.

CONCLUSIONS

In the context of NSTEMI, we observed a trans-cardiac decrease in CRP, which may indicate the first human in vivo proof of a net CRP uptake by the myocardium, with a role for CRP both in the injured and adjacent myocardium.

Single-arm, open-label, dose-escalation phase I study to evaluate the safety of a herbal medicine SH003 in patients with solid cancer: a study protocol

INTRODUCTION

Cancer is a major health problem worldwide and the leading cause of death in many countries. The number of patients with cancer and socioeconomic costs of cancer continues to increase. SH003 is a novel herbal medicine consisting of Astragalus membranaceus, Angelica gigas and Trichosanthes Kirilowii Maximowicz. Preclinical studies have shown that SH003 has therapeutic anticancer effects. The aim of this study is to determine the maximum tolerated dose of SH003 in patients with solid cancers.

METHODS AND ANALYSIS

This study is an open-label, dose-escalation trial evaluating the safety and tolerability of SH003. The traditional 3+3 dose-escalation design will be implemented. Patients with solid cancers will be recruited. According to dose level, the patients will receive one to four tablets of SH003, three times a day for 3 weeks. Toxicity will be evaluated using common terminology criteria for adverse events (CTCAE). Dose-limiting toxicities are defined as grade 3 or higher adverse events based on CTCAE. The maximum tolerated dose will be determined by the highest dose at which no more than one of six patients experiences dose-limiting toxicity.

ETHICS AND DISSEMINATION

This study has been approved by the institutional review board of the Ajou University Hospital (reference AJIRB-MED-CT1-16-311). The results of this study will be disseminated through a scientific journal and a conference.

TRIAL REGISTRATION NUMBER

NCT03081819; Pre-results.

Sipjeondaebo-tang in patients with breast cancer with fatigue: a protocol for a pilot, randomised, double-blind, placebo-controlled, cross-over trial

INTRODUCTION

Cancer-related fatigue is a frequent symptom in patients with cancer and one of the most distressing symptoms in patients with breast cancer. Sipjeondaebo-tang (Juzen-taiho-to in Japanese or Shi-Quan-Da-Bu-Tang in Chinese) is a widely used herbal medicine for the treatment of fatigue in Korea, China and Japan. The purpose of the present study is to evaluate the feasibility of Sipjeondaebo-tang for cancer-related fatigue.

METHODS AND ANALYSIS

The present study is a randomised, double-blind, placebo-controlled, cross-over study. Forty-eight patients with breast cancer who are indicated for doxorubicin and cyclophosphamide will be recruited. The participants will receive 3 g of Sipjeondaebo-tang or a placebo three times a day for 56 days. The primary outcome measurement is the change in the Brief Fatigue Inventory scores. The secondary outcome measurements include the changes in the Visual Analogue Scale (VAS) of fatigue, and quality of life measured by the European Organization for Research and Treatment of Cancer-QLQ-C30 and QLQ-BR23. VAS of fatigue will be measured on every visit, and other outcomes will be measured on visits 2, 4, 6 and 7. The total study period is 14 weeks.

ETHICS AND DISSEMINATION

This study has been approved by the Institutional Review Board of the Catholic Kwandong University International St Mary's Hospital (reference IS16MNSI0011). The results of this study will be published in a peer-reviewed journal and presented at a scientific conference.

TRIAL REGISTRATION NUMBER

NCT02858856; Pre-results.

Non-alcoholic steatofibrosis (NASF) can independently predict mortality in patients with non-alcoholic fatty liver disease (NAFLD)

Background

Hepatic fibrosis in patients with non-alcoholic fatty liver disease (NAFLD) independently predicts mortality. Given liver biopsy’s invasive nature, non-invasive method to assess hepatic steatosis and fibrosis provides NAFLD risk stratification algorithm in clinical practice. NAFLD fibrosis score (NFS) is simple and non-invasive predictive model recommended by American Association for the Study of Liver Disease (AASLD) Guideline to identify patients with NAFLD with fibrosis risk. The aim of this study is to assess long-term outcomes of subjects with significant non-alcoholic steatofibrosis (NASF) as established by ultrasound (US) and NFS.

Methods

Used National Health and Nutrition Examination Survey (NHANES III) with National Death Index-linked Mortality Files. NAFLD diagnosis established by the presence of moderate to severe hepatic steatosis on US without other causes of chronic liver disease (alcohol consumption <20 gr/day, hepatitis B surface-antigen negative, anti-hepatitis C virus antibody negative, transferrin saturation <50%). Significant hepatic fibrosis was estimated by high NFS (>0.676) and calculated with previously published formula. Subjects with NAFLD and high NFS have significant NASF.

Results

NHANES III included 20 050 adult participants. 2515 participants complete data and NAFLD with 5.1% (n=129) meeting criteria for significant SF. Subjects with significant SF were older, had higher body mass index, waist circumference and the homeostasis model assessment (HOMA) scores and higher rates of comorbidities (diabetes, congestive heart failure (CHF), stroke; all p<0.001). After median of 207 months of follow-up, overall mortality in NAFLD cohort was 30.0% (n=754). Crude mortality higher in subjects with significant SF (67.4% vs 28.0%, p<0.001). In multivariate survival analysis, predictors of overall mortality included significant SF (adjusted HR (aHR): 1.37; 95% CI 1.07 to 1.76, p=0.01), older age (aHR:1.08; 95% CI 1.07 to 1.09 per year), male gender (aHR:1.44; 95% CI 1.24 to 1.67), black race (aHR:1.24; 95% CI 1.04 to 1.48)), history of hypertension (aHR:1.40; 95% CI 1.20 to 1.64), diabetes (aHR:1.69; 95% CI 1.43 to 2.00), CHF (aHR:1.77; 95% CI 1.38 to 2.261), stroke (aHR:1.84; 95% CI 1.38 to 2.48) and smoking (aHR:1.74; 95% CI 1.47 to 2.07) (all p<0.02). Sensitivity analysis showed that the best association of SF with mortality is higher at NFS threshold of 0.80 (aHR:1.41; 95% CI 1.09 to 1.83, p=0.01).

Conclusions

Significant NASF determined non-invasively is an independent predictor of mortality. These data should help clinicians to easily risk-stratify patients with NAFLD for close monitoring and treatment considerations in clinical trial setting.

Cumulative retention rate of adalimumab in patients with Behçet’s disease-related uveitis: a four-year follow-up study

Background/aims

Adalimumab (ADA) has been shown to be an effective treatment for Behçet’s disease (BD)-related uveitis. We aimed at evaluating the cumulative retention rate of ADA during a 48-month follow-up period in patients with BD-related uveitis, the impact of a concomitant use of disease modifying anti-rheumatic drugs (DMARDs) on ADA retention rate, and differences according to the various lines of biologic therapy (ie, first- vs second-line or more). Predictive factors of response to ADA were also investigated.

Methods

We enrolled patients diagnosed with BD-related uveitis and treated with ADA between January 2009 and December 2016. Cumulative survival rates were studied using the Kaplan-Meier plot, while the log-rank (Mantel-Cox) test was used to compare survival curves. Statistical analysis was performed to identify differences according to the response to ADA.

Results

54 consecutive patients (82 eyes) were eligible for analysis. The drug retention rate at 12- and 48-month follow-up was 76.9% and 63.5%, respectively. No statistically significant differences were identified according to the use of concomitant DMARDs (p=0.27) and to the different lines of ADA treatment (p=0.37). No significant differences were found between patients continuing and discontinuing ADA in terms of age (p=0.24), age at BD onset (p=0.81), age at uveitis onset (p=0.56), overall BD duration (p=0.055), uveitis duration (p=0.46), human leucocyte antigen-B51 positivity (p=0.51), and gender (p=0.47).

Conclusions

ADA retention rate in BD-related uveitis is excellent and is not affected by the concomitant use of DMARDs or by the different lines of biological therapy. Negative prognostic factors for BD uveitis do not impact ADA efficacy.

Combined Use of Neutrophil to Lymphocyte Ratio and C-Reactive Protein Level to Predict Clinical Outcomes in Acute Myocardial Infarction Patients Undergoing Percutaneous Coronary Intervention

Background and Objectives

Both neutrophil to lymphocyte ratio (NLR) and C-reactive protein (CRP) are biomarkers associated with poor prognosis of patients with acute myocardial infarction (AMI). However, the combined usefulness of NLR and CRP in predicting adverse outcomes has not been investigated.

Subjects and Methods

We analyzed 381 consecutive AMI patients who underwent percutaneous coronary intervention (PCI) from January 2012 to January 2014. The endpoints were all-cause mortality, recurrent myocardial infarction (MI), stent thrombosis, repeat revascularization, stroke, and major adverse cardiac and cerebrovascular events (MACCE) at 2-year follow-up. Included patients were divided into 4 groups according to the optimal cut-off values for NLR and CRP on receiver operating characteristic analysis predicting mortality.

Results

Patients with both high NLR (>6.30) and high CRP (>0.76) had significantly greater risk of all-cause death and MACCE at 24 months, with no significant increase in the risk of recurrent MI, stent thrombosis, or stroke compared with patients with either low NLR or low CRP, as well as those with low NLR and low CRP. Kaplan-Meier analysis revealed significantly lower survival in patients with high NLR-CRP. On Cox multivariate analysis, high NLR-CRP (hazard ratio 23.172, 95% confidence interval 6.575 to 81.671, p<0.001) was an independent predictor of all-cause death.

Conclusion

Elevated levels of both NLR and CRP are associated with increased risk of long-term mortality in AMI patients who have undergone PCI.

Functional Transformation of C-reactive Protein by Hydrogen Peroxide

C-reactive protein (CRP) is present at sites of inflammation including amyloid plaques, atherosclerotic lesions, and arthritic joints. CRP, in its native pentameric structural conformation, binds to cells and molecules that have exposed phosphocholine (PCh) groups. CRP, in its non-native pentameric structural conformation, binds to a variety of deposited, denatured, and aggregated proteins, in addition to binding to PCh-containing substances. In this study, we investigated the effects of H2O2, a prototypical reactive oxygen species that is also present at sites of inflammation, on the ligand recognition function of CRP. Controlled H2O2 treatment of native CRP did not monomerize CRP and did not affect the PCh binding activity of CRP. In solid phase ELISA-based ligand binding assays, purified pentameric H2O2-treated CRP bound to a number of immobilized proteins including oxidized LDL, IgG, amyloid β peptide 1-42, C4b-binding protein, and factor H, in a CRP concentration- and ligand concentration-dependent manner. Using oxidized LDL as a representative protein ligand for H2O2-treated CRP, we found that the binding occurred in a Ca2+-independent manner and did not involve the PCh-binding site of CRP. We conclude that H2O2 is a biological modifier of the structure and ligand recognition function of CRP. Overall, the data suggest that the ligand recognition function of CRP is dependent on the presence of an inflammatory microenvironment. We hypothesize that one of the functions of CRP at sites of inflammation is to sense the inflammatory microenvironment, change its own structure in response but remain pentameric, and then bind to pathogenic proteins deposited at those sites.

Purification of recombinant C-reactive protein mutants

C-reactive protein (CRP) is an evolutionarily conserved protein, a component of the innate immune system, and an acute phase protein in humans. In addition to its raised level in blood in inflammatory states, CRP is also localized at sites of inflammation including atherosclerotic lesions, arthritic joints and amyloid plaque deposits. Results of in vivo experiments in animal models of inflammatory diseases indicate that CRP is an anti-pneumococcal, anti-atherosclerotic, anti-arthritic and an anti-amyloidogenic molecule. The mechanisms through which CRP functions in inflammatory diseases are not fully defined; however, the ligand recognition function of CRP in its native and non-native pentameric structural conformations and the complement-activating ability of ligand-complexed CRP have been suggested to play a role. One tool to understand the structure-function relationships of CRP and determine the contributions of the recognition and effector functions of CRP in host defense is to employ site-directed mutagenesis to create mutants for experimentation. For example, CRP mutants incapable of binding to phosphocholine are generated to investigate the importance of the phosphocholine-binding property of CRP in mediating host defense. Recombinant CRP mutants can be expressed in mammalian cells and, if expressed, can be purified from the cell culture media. While the methods to purify wild-type CRP are well established, different purification strategies are needed to purify various mutant forms of CRP if the mutant does not bind to either calcium or phosphocholine. In this article, we report the methods used to purify pentameric recombinant wild-type and mutant CRP expressed in and secreted by mammalian cells.

Transitional changes in the CRP structure lead to the exposure of proinflammatory binding sites

C-reactive protein (CRP) concentrations rise in response to tissue injury or infection. Circulating pentameric CRP (pCRP) localizes to damaged tissue where it leads to complement activation and further tissue damage. In-depth knowledge of the pCRP activation mechanism is essential to develop therapeutic strategies to minimize tissue injury. Here we demonstrate that pCRP by binding to cell-derived microvesicles undergoes a structural change without disrupting the pentameric symmetry (pCRP*). pCRP* constitutes the major CRP species in human-inflamed tissue and allows binding of complement factor 1q (C1q) and activation of the classical complement pathway. pCRP*–microvesicle complexes lead to enhanced recruitment of leukocytes to inflamed tissue. A small-molecule inhibitor of pCRP (1,6-bis(phosphocholine)-hexane), which blocks the pCRP–microvesicle interactions, abrogates these proinflammatory effects. Reducing inflammation-mediated tissue injury by therapeutic inhibition might improve the outcome of myocardial infarction, stroke and other inflammatory conditions.

C-reactive protein is a pentameric protein secreted by the liver in response to injury and infection. Here Braig et al. show that conformational changes in CRP on the surface of monocyte-derived microvesicles enable binding of complement C1q and lead to activation of the complement cascade and aggravation of inflammation.

C-Reactive Protein and Hemogram Parameters for the Non-Sepsis Systemic Inflammatory Response Syndrome and Sepsis: What Do They Mean?

Objectives

Sepsis is one of the most common reasons of increased mortality and morbidity in the intensive care unit. The changes in CRP levels and hemogram parameters and their combinations may help to distinguish sepsis from non-sepsis SIRS. The aim of this study is to investigate the CRP and hemogram parameters as an indicator of sepsis.

Methods

A total of 2777 patients admitted to the ICU of two centers between 2006–2013 were evaluated retrospectively. The patients were diagnosed as SIRS (-), non-sepsis SIRS and sepsis. The patients who were under 18 years old, re-admitted, diagnosed with hematological disease, on corticosteroid and immunosuppressive therapy, SIRS (-), culture negative, undocumented laboratory values and outcomes were excluded. 1257 patients were divided into 2 groups as non-sepsis SIRS and sepsis. The patients’ demographic data, CRP levels, hemogram parameters, length of ICU stay and mortality were recorded.

Results

1257 patients were categorized as non-sepsis SIRS (816, 64.9%) and sepsis (441, 35.1%). In the multivariate analysis, the likelihood of sepsis was increased 3.2 (2.2–4.6), 1.7 (1.2–2.4), 1.6 (1.2–2.1), 2.3 (1.4–3.8), 1.5 (1.1–2.1) times by the APACHE II≥13, SOFA score≥4, CRP≥4.0, Lym_C<0.45 and PLT_C<150 respectively (p<0.001 p = 0.007 p = 0.004 p<0.001 p = 0.027). The likelihood of sepsis was increased 18.1 (8.4–38.7) times by the combination of CRP≥4.0, lym_C<0.45 and PLT_C<150 (P<0.001).

Conclusions

While WBC_C, Neu_C, Neu%, NLCR and Eo_C are far from being the indicators to distinguish sepsis from non-sepsis SIRS, the combinations of CRP, Lym_C and PLT_C can be used to determine the likelihood of sepsis.

Classical and Alternative Activation of Cyanobacterium Oscillatoria sp. Lipopolysaccharide-Treated Rat Microglia in vitro

The purpose of this investigation was to test the hypothesis that an in vitro exposure to cyanobacterium Oscillatoria sp. Lipopolysaccharide (LPS) might result in classical and alternative activation of rat neonatal microglia. Using Escherichia coli LPS-primed microglia as a positive control, this study revealed that treatment of rat microglia with Oscillatoria sp. LPS for 17 h in vitro resulted in both classical and alternative activation as well as concomitant pro-inflammatory and anti-inflammatory mediator release, in a concentration-dependent manner: (1) treatment with 0.1-10 000 ng/ml Oscillatoria sp. LPS resulted in minimal lactic dehydrogenase (LDH) release, induced concentration-dependent and statistically significant O2 (-) generation, matrix metalloproteinase-9 (MMP-9) release, generation of the cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and the chemokines macrophage inflammatory protein-2 (MIP-2/CXCL2), interferon γ-induced protein 10 kDa (IP-10/CXCL-10), (MIP-1α/CCL3), monocyte chemotactic protein-1 (MCP-1/CCL2), regulated on activation, normal T cell expressed and secreted (RANTES/CCL5), and the alternative activation cytokine IL-10; (3) in contrast, treatment with 100 000 ng/ml Oscillatoria sp. LPS appeared to damage the microglia cell membrane, because it resulted in minimal O2 (-) generation, statistically significant LDH release, and a decrease in the generation of all the cytokines and chemokines investigated, with the exception of IL-1α and cytokine-induced neutrophil chemoattractant 1 (CINC-1/CXCL1) generation, which was increased. Thus, our results provide experimental support for our working hypothesis, namely that Oscillatoria sp. LPS induces classical and alternative activation of rat brain microglia in vitro in a concentration-dependent manner, namely 0.1-10 000 ng/ml Oscillatoria sp. LPS, when microglia cells were shown to be viable. Furthermore, should cyanobacterium Oscillatoria sp. LPS gain entry into the CNS, our findings suggest that classical and alternative activation of rat brain microglia in vivo, might lead to concomitant mediator release that could result in an interplay between neuroinflammation and neural repair in a concentration-dependent manner.