Circulating Calprotectin as a Biomarker of COVID-19 Severity.

INTRODUCTION: Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Although demographic and clinical parameters such as sex, age, comorbidities, genetic background and various biomarkers have been identified as risk factors, there is an unmet need to predict the risk and onset of severe inflammatory disease leading to poor clinical outcomes. In addition, very few mechanistic biomarkers are available to inform targeted treatment of severe (auto)-inflammatory conditions associated with COVID-19. Calprotectin, also known as S100A8/S100A9, MRP8/14 (Myeloid-Related Protein) or L1, is a heterodimer involved in neutrophil-related inflammatory processes. In COVID-19 patients, calprotectin levels were reported to be associated with poor clinical outcomes such as significantly reduced survival time, especially in patients with severe pulmonary disease. AREAS COVERED: Pubmed was searched using the following keywords: Calprotectin + COVID19, S100A8/A9 + COVID19, S100A8 + COVID-19, S100A9 + COVID-19, MRP8/14 + COVID19; L1 + COVID-19 between May 2020 and 8 March 2021. The results summarized in this review provide supporting evidence and propose future directions that define calprotectin as an important biomarker in COVID-19. EXPERT OPINION: Calprotectin represents a promising serological biomarker for the risk assessment of COVID-19 patients.

Increased expressions of cellular ATP-binding cassette transporters may be a promising diagnostic marker for colorectal cancer.

OBJECTIVES: To measure the blood expression levels of related drug-resistant ATP-binding cassette (ABC) transporters in colorectal cancer (CRC) patients and to assess these examined transporters for whether they present signi cant expression in connection with the tumor appearance of CRC. METHODS: In this case-control study, the messenger ribonucleic acids were isolated from the blood of 62 CRC patients who were recruited from King Abdulaziz University Hospital Oncology Clinic and 46 controls from King Fahad General Hospital Blood Bank (Jeddah, Saudi Arabia) from September 2016 to March 2017. The Biomedical Ethics Unit at King Abdulaziz University, Jeddah, Saudi Arabia approved this study. The expressions of ABC transporters were measured using quantitative polymerase chain reaction. GraphPad Prism 5 and REST 2009 Software were used to correlate the expressions with clinicopathological independent stages and body mass index. A p-value of less than 0.05 was considered significant. RESULTS: The results showed that the 3 ABC transporters, particularly ABCC1 (p less than 0.0001), were highly expressed in the blood of CRC patients compared with controls. However, none of the 3 transporters was related to the progression of CRC, age, gender, or body mass index. CONCLUSION: The expressions of ABC transporters were found to be significantly higher in CRC patients, and they may act as diagnostic markers and should potentially be tested for their contribution to drug sensitivity in CRC patients.

Expression quantitative trait loci in ABC transporters are associated with survival in 5-FU treated colorectal cancer patients.

The chemotherapeutic efficacy in colorectal cancer (CRC) is limited due to the inter-individual variability in drug response and the development of tumour resistance. ATP-binding cassette (ABC) transporters are crucial in the development of resistance by the efflux of anticancer agents from cancer cells. In this study, we identified 14 single nucleotide polymorphisms (SNPs) in 11 ABC transporter genes acting as an expression of quantitative trait loci (eQTLs), i.e. whose variation influence the expression of many downstream genes. These SNPs were genotyped in a case-control study comprising 1098 cases and 1442 healthy controls and analysed in relation to CRC development risk and patient survival. Considering a strict correction for multiple tests, we did not observe any significant association between SNPs and CRC risk. The rs3819720 polymorphism in the ABCB3/TAP2 gene was statistically significantly associated with shorter overall survival (OS) in the codominant, and dominant models [GA vs. GG, hazard ratio (HR) = 1.48; P = 0.002; AA vs. GG, HR = 1.70; P = 0.004 and GA + AA vs. GG, HR = 1.52; P = 0.0006]. Additionally, GA carriers of the same SNP displayed worse OS after receiving 5-FU based chemotherapy. The variant allele of rs3819720 polymorphism statistically significantly affected the expression of 36 downstream genes. Screening for eQTL polymorphisms in relevant genes such as ABC transporters that can regulate the expression of several other genes may help to identify the genetic background involved in the individual response to the treatment of CRC patients.

MRP8/14 and neutrophil elastase for predicting treatment response and occurrence of flare in patients with juvenile idiopathic arthritis.

OBJECTIVE: To study two neutrophil activation markers, myeloid-related protein (MRP) 8/14 and neutrophil elastase (NE), for their ability to predict treatment response and flare in patients with JIA. METHODS: Using samples from two cohorts (I and II), we determined MRP8/14 and NE levels of 32 (I) and 81 (II) patients with new-onset, DMARD-naïve arthritis and compared patients who responded to treatment (defined as fulfilling ≥ adjusted ACRpedi50 response and/or inactive disease) with non-responders (defined as fulfilling < adjusted ACRpedi50 response and/or active disease) at 6 and 12 months. Secondly, we compared biomarker levels of 54 (I) and 34 (II) patients with clinically inactive disease who did or did not suffer from a flare of arthritis after 6 or 12 months. Receiver operating characteristic analyses were carried out to study the predictive value of MRP8/14 and NE for treatment response and flare. RESULTS: For both cohorts, baseline MRP8/14 and NE levels for patients who did or did not respond to treatment were not different. Also, MRP8/14 and NE levels were not different in patients who did or did not flare. Receiver operating characteristic analysis of MRP8/14 and NE demonstrated areas under the curve <0.7 in both cohorts. CONCLUSION: In our cohorts, MRP8/14 and NE could not predict treatment response. Also, when patients had inactive disease, neither marker could predict flares.

Association of ABCC Gene Polymorphism With Susceptibility to Antituberculosis Drug-Induced Hepatotoxicity in Western Han Patients With Tuberculosis.

Six-month combination regimens could lead to serious hepatotoxicity, which may limit the clinical use of antituberculosis drugs. ABCC transporters are critical to the influx and efflux of compounds into and out of cells. The aim of this study was to explore whether the genetic variants in ABCC genes were related to the development of antituberculosis drug-induced hepatotoxicity. Here, we screened and genotyped 39 single-nucleotide polymorphisms of 13 ABCC genes in 746 eligible patients treated by first-line antituberculosis drugs in Western China Hospital. Genomic DNA was extracted from a peripheral blood sample of each patient, and clinical symptoms and laboratory results were recorded regularly. We found that the incidence rate of hepatotoxicity was 15.8% in the western Chinese Han population. As a result, the ABCC2 rs3740065 genotype, sex, and the baseline level of alanine aminotransferase are independent risk factors of antituberculosis drug-induced hepatotoxicity, with P values of .008, .014, and <.001, respectively. Our findings revealed a fraction of the underlying mechanism of hepatotoxicity, and larger validation studies on different populations are warranted to confirm these findings.

Initiation of the ABCD3-I algorithm for expediated evaluation of transient ischemic attack patients in an emergency department.

BACKGROUND: The use of ABCD3-I score for Transient ischemic attack (TIA) evaluation has not been widely investigated in the ED. We aim to determine the performance and cost-effectiveness of an ABCD3-I based pathway for expedited evaluation of TIA patients in the ED. METHODS: We conducted a single-center, pre- and post-intervention study among ED patients with possible TIA. Accrual occurred for seven months before (Oct. 2016-April 2017) and after (Oct. 2017-April 2018) implementing the ABCD3-I algorithm with a five-month wash-in period (May-Sept. 2017). Total ED length of stay (LOS), admissions to the hospital, healthcare cost, and 90-day ED returns with subsequent stroke were analyzed and compared. RESULTS: Pre-implementation and post-implementation cohorts included 143 and 118 patients respectively. A total of 132 (92%) patients were admitted to the hospital in the pre-implementation cohort in comparison to 28 (24%) patients admitted in the post-implementation cohort (p < 0.001) with similar 90-day post-discharge stroke occurrence (2 in pre-implementation versus 1 in post-implementation groups, p > 0.05). The mean ABCD2 scores were 4.5 (1.4) in pre- and 4.1 (1.3) in post-implementation cohorts (p = 0.01). The mean ABCD3-I scores were 4.5 (1.8) in post-implementation cohorts. Total ED LOS was 310 min (201, 420) in pre- and 275 min (222, 342) in post-implementation cohorts (p > 0.05). Utilization of the ABCD3-I algorithm saved an average of over 40% of total healthcare cost per patient in the post-implementation cohort. CONCLUSIONS: The initiation of an ABCD3-I based pathway for TIA evaluation in the ED significantly decreased hospital admissions and cost with similar 90-day neurological outcomes.

Nilotinib interferes with cell cycle, ABC transporters and JAK-STAT signaling pathway in CD34+/lin- cells of patients with chronic phase chronic myeloid leukemia after 12 months of treatment.

Chronic myeloid leukemia (CML) is characterized by the constitutive tyrosine kinase activity of the oncoprotein BCR-ABL1 in myeloid progenitor cells that activates multiple signal transduction pathways leading to the leukemic phenotype. The tyrosine-kinase inhibitor (TKI) nilotinib inhibits the tyrosine kinase activity of BCR-ABL1 in CML patients. Despite the success of nilotinib treatment in patients with chronic-phase (CP) CML, a population of Philadelphia-positive (Ph+) quiescent stem cells escapes the drug activity and can lead to drug resistance. The molecular mechanism by which these quiescent cells remain insensitive is poorly understood. The aim of this study was to compare the gene expression profiling (GEP) of bone marrow (BM) CD34+/lin- cells from CP-CML patients at diagnosis and after 12 months of nilotinib treatment by microarray, in order to identify gene expression changes and the dysregulation of pathways due to nilotinib action. We selected BM CD34+/lin- cells from 78 CP-CML patients at diagnosis and after 12 months of first-line nilotinib therapy and microarray analysis was performed. GEP bioinformatic analyses identified 2,959 differently expressed probes and functional clustering determined some significantly enriched pathways between diagnosis and 12 months of nilotinib treatment. Among these pathways, we observed the under expression of 26 genes encoding proteins belonging to the cell cycle after 12 months of nilotinib treatment which led to the up-regulation of chromosome replication, cell proliferation, DNA replication, and DNA damage checkpoint at diagnosis. We demonstrated the under expression of the ATP-binding cassette (ABC) transporters ABCC4, ABCC5, and ABCD3 encoding proteins which pumped drugs out of the cells after 12 months of nilotinib. Moreover, GEP data demonstrated the deregulation of genes involved in the JAK-STAT signaling pathway. The down-regulation of JAK2, IL7, STAM, PIK3CA, PTPN11, RAF1, and SOS1 key genes after 12 months of nilotinib could demonstrate the up-regulation of cell cycle, proliferation and differentiation via MAPK and PI3K-AKT signaling pathways at diagnosis.

Expanding the Mutation Spectrum in ABCA4: Sixty Novel Disease Causing Variants and Their Associated Phenotype in a Large French Stargardt Cohort.

Here we report novel mutations in ABCA4 with the underlying phenotype in a large French cohort with autosomal recessive Stargardt disease. The DNA samples of 397 index subjects were analyzed in exons and flanking intronic regions of ABCA4 (NM_000350.2) by microarray analysis and direct Sanger sequencing. At the end of the screening, at least two likely pathogenic mutations were found in 302 patients (76.1%) while 95 remained unsolved: 40 (10.1%) with no variants identified, 52 (13.1%) with one heterozygous mutation, and 3 (0.7%) with at least one variant of uncertain significance (VUS). Sixty-three novel variants were identified in the cohort. Three of them were variants of uncertain significance. The other 60 mutations were classified as likely pathogenic or pathogenic, and were identified in 61 patients (15.4%). The majority of those were missense (55%) followed by frameshift and nonsense (30%), intronic (11.7%) variants, and in-frame deletions (3.3%). Only patients with variants never reported in literature were further analyzed herein. Recruited subjects underwent complete ophthalmic examination including best corrected visual acuity, kinetic and static perimetry, color vision test, full-field and multifocal electroretinography, color fundus photography, short-wavelength and near-infrared fundus autofluorescence imaging, and spectral domain optical coherence tomography. Clinical evaluation of each subject confirms the tendency that truncating mutations lead to a more severe phenotype with electroretinogram (ERG) impairment (p = 0.002) and an earlier age of onset (p = 0.037). Our study further expands the mutation spectrum in the exonic and flanking regions of ABCA4 underlying Stargardt disease.

Myeloid related proteins are up-regulated in autoimmune thyroid diseases and activate toll-like receptor 4 and pro-inflammatory cytokines in vitro.

PURPOSE: Myeloid-related protein (MRP) family plays an important role in the promotion of cell proliferation and the production of inflammatory cytokines. We investigated the expression of MRP6, MRP8 and MRP14 in thyroid tissues, serum, and peripheral blood monocular cells (PBMCs) in patients with autoimmune thyroid diseases (AITD). METHOD: The expression of MRP6, MRP8, and MRP14 was investigated using immunohistochemical staining and quantitative real-time polymerase chain reaction in the thyroid glands of 7 patients with Graves' disease (GD), 8 with Hashimoto's thyroiditis (HT), and 7 healthy controls (HC). The serum levels of MRP8/MRP14 complex and MRP6 were investigated in 30 patients with GD, 36 with HT, and 30 with HC. The mRNA expression of MRP proteins in PBMCs was also explored. PBMCs from each group were incubated with MPRs and their effect on Toll-like receptor 4(TLR4) expression and their effect on the levels of the pro-inflammatory cytokines in supernatant were analyzed upon incubating with TLR4 and signaling pathways inhibitors. RESULTS: Serum levels of MRP8/MRP14 and MRP6 were up-regulated in patients with AITD. In addition, mRNA expression of MRP proteins in PBMCs and the thyroid gland was markedly elevated in AITD patients. MRP6 and MPR8 promoted the secretion of TNF-α and IL-6 in cultured PBMCs, and this elevation was more pronounced in AITD patients; we also found that this up-regulation was regulated by TLR4/phosphoinositide 3-kinase/nuclear factor-κB signaling pathway. CONCLUSION: The expression of MRP proteins was elevated in AITD patients. Therefore, an MRP-TLR4 dependent signaling may play an important role in the pathogenesis of AITD.

Clinical Significance of Myeloid-Related Protein 8/14 as a Predictor for Biological Treatment and Disease Activity in Rheumatoid Arthritis.

OBJECTIVES: To investigate the serum level of Myeloid-Related Protein 8/14 complex (MRP8/14) and to predict and monitor the response to biologic treatment in rheumatoid arthritis (RA) patients. METHODS: Each patient underwent clinical examination and blood sampling for assessment of serum high-sensitivity C-reactive protein (hs-CRP) levels, erythrocyte sedimentation rate (ESR), rheumatoid factors (RF), anti-cyclic citrullinated protein antibodies (anti-CCP), and serum concentrations of MRP8/14 protein complexes (myeloid-related proteins, MRP8/14) were measured at baseline, and weeks 4 and 12 (after initiation of treatment). RESULTS: Serum MRP8/14 protein complex levels correlated with DAS28 and anti-CCP antibody. MRP8/14 protein complex levels decreased significantly after 12 weeks treatment with biological therapy: mono-rhTNFR-Fc active group. rhTNFR-Fc plus methotrexate (MTX) decreased MRP8/14 protein complex levels from 11839±1849 ng/ml to 5423±1130 ng/ml (p<0.01) a reduction of 54.2% compared with 32.9% in the rhTNFR-Fc group. CONCLUSIONS: MRP8/14 protein complex levels were increased in active stage RA patients. MRP8/14 levels were decreased with rhTNFR-Fc treatment, suggesting serum concentrations of MRP8/14 protein complex might be a promising biomarker to predict responses to biological therapy in active RA patients at baseline and could be used to monitor responses to treatment across different mechanisms of action.

ATP Binding Cassette Subfamily A Member 2 (ABCA2) Expression and Methylation are Associated with Alzheimer's Disease.

BACKGROUND ABCA2 has been genetically linked to Alzheimer's disease (AD) risk, but its mRNA expression and epigenetics in AD have not been investigated. MATERIAL AND METHODS To explore the diagnosis value of ABCA2 mRNA expression in AD, 2 datasets GES15222 and GSE33000 containing expression profile of brain cortex tissues and 2 datasets GSE63063 (Cohort 1) and GSE63063 (Cohort 2) containing expression profile of blood were downloaded from the NCBI GEO database and analyzed by receiver operating characteristic curve (ROC) analyses and logistic regression. The ABCA2 co-expressed genes were also analyzed by GO annotation to investigate the potential molecular mechanisms. RESULTS The analyses results suggested ABCA2 mRNA expression was upregulated significantly in AD compared with controls in all datasets. ROC analysis suggested that ABCA2 was associated with AD in all datasets, which were also proved by univariate and multivariate analyses. Next, the dataset GSE80970 containing methylation profiles of prefrontal cortex tissues from AD patients were downloaded and analyzed. Methylation of 2 of 36 CpG islands in ABCA2 gene with high diagnostic accuracy of AD from controls in ROC analyses were found to be negatively associated with AD risk in univariate analysis. One was still associated with AD risk after adjustment of confounding factors. Additional analyses indicated that ACBA2 mRNA expression could be used to diagnose mild cognitive impairment (MCI) and Huntington's disease (HD) from controls and to distinguish HD from AD, but not AD from MCI. Furthermore, the genes involved in AD during ABCA2 alteration were analyzed by GO analysis. CONCLUSIONS ABCA2 mRNA expression and methylation is associated AD risk. ABCA2 may be used as a biomarker for AD diagnosis and may be a potential therapeutic target of AD.

Haematological involvement associated with a mild autoinflammatory phenotype, in two patients carrying the E250K mutation of PSTPIP1.

OBJECTIVES: Hyperzincaemia/hypercalprotectinemia (Hz/Hc) syndrome is a recently described condition caused by a specific de novo mutation (E250K) affecting PSTPIP1 gene. It has a phenotype distinct from classical pyogenic arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome that includes severe systemic and cutaneous inflammation, hepatosplenomegaly, arthritis without sequelae, pancytopenia and failure to thrive. METHODS: We describe an 8-year-old boy who presented recurrent right knee swelling mimicking septic arthritis and persistent bone marrow involvement, without cutaneous involvement. RESULTS: Molecular analysis of the PSTPIP1 gene revealed the presence of a heterozygous E250K mutation. No growth failure was detected nor in the patient neither in his mother, carrying the same variant. Blood zinc and calprotectin MRP8/14 concentrations of the patient were found to be markedly increased. Therapy with anakinra was started with rapid disappearance of clinical symptoms and normalization of CRP levels in 24 hours, but persistence of bone marrow involvement. CONCLUSIONS: The patient described has a milder phenotype, with no skin features, minor episodes of arthritis with no sequelae and normal growth. Compared to the patients with de novo mutations described in the literature, familial cases seem to have a milder phenotype. Our case further confirms the lack of efficacy of anakinra on bone marrow involvement.

Cardiometabolic risk markers, adipocyte fatty acid binding protein (aFABP) and the impact of high-intensity interval training (HIIT) in obese adolescents.

OBJECTIVE: The impact of high-intensity interval training (HIIT) as well as the association between the adipocyte fatty binding protein (aFABP) and cardiometabolic risk factors in overweight adolescents was investigated. METHODS: Twenty-eight adolescents (13-18years; BMI≥90th percentile according to German reference values) were offered HIIT twice weekly for 6months. At baseline and after program completion, anthropometric, clinical and metabolic characteristics were assessed and a fasting blood sample was obtained. Leptin, adiponectin, visfatin and aFABP were measured using commercially available kits. DNA methylation at RALBP1 was assessed using pyrosequencing. Descriptive statistics, Pearson's correlation and linear models were calculated. RESULTS: Mean age at start of the program was 15.5±1.4years (53.5% females) and 20/28 (71%) provided follow-up data. At baseline, aFABP was correlated with BMI-SDS (0.48 [0.13,0.72]; p=0.0095), waist-to-height-ratio (0.63 [0.33,0.81], p=0.00036) and body fat content (0.55 [0.21, 0.77]; p=0.0031). Certain markers of metabolic risk were significantly correlated with aFABP (HOMA-IR 0.52 [0.19, 0.75], p=0.0044; γGT 0.48 [0.13, 0.73], p=0.0091; uric acid 0.46 [0.11, 0.71] p=0.013; HDL-C -0.39 [-0.66, -0.01] p=0.043; triglycerides 0.38 [0.01, 0.66], p=0.047). With the exception of triglycerides, these associations vanished after adjusting for BMI-SDS. aFABP did not depend on sex, age or pubertal stage in obese adolescents. After the HIIT program, small but significant reductions were observed in waist-to-height-ratio, (0.013 [0.0025, 0.024]; p=0.023), skin-fold based body fat content (2.0% [0.6, 3.5]; p=0.011), and standard deviation score of systolic blood pressure (0.69 [0.26 to 1.1]; p=0.0036). No changes were observed in adipokines or epigenetic markers following the program. CONCLUSION: HIIT may have beneficial effects on body composition and cardiometabolic health in overweight adolescents. Like in adults, aFABP seems to be associated with markers of metabolic risk in obese adolescents.

Gene Expression and Methylation Analysis of ABCA7 in Patients with Alzheimer's Disease.

BACKGROUND/OBJECTIVE: The aim of this study was to examine the blood gene expression and methylation of ATP-binding cassette sub-family A member 7 gene (ABCA7) as a biological marker of AD. METHODS: AD subjects (n = 50; 11 males, 77.7±6.05 years old) and age- and sex-matched healthy controls (n = 50) were recruited. A single nucleotide polymorphism in ABCA7 (rs3764650), methylation rates of CpG sites in the ABCA7 promoter region, and ABCA7 mRNA expression levels in peripheral blood were examined. RESULTS: The distribution of the rs3764650 polymorphism in AD subjects was not different from that of controls. Although the methylation rates of AD subjects were not significantly different from those of controls, the ABCA7 mRNA expression level in AD subjects was significantly higher than that in controls. Additionally, the ABCA7 mRNA expression level in AD subjects was significantly correlated with Mini-Mental State Examination recall, the Alzheimer's Disease Assessment Scale total score, and the Clinical Dementia Rating score. We also found a significant correlation between the ABCA7 mRNA expression level and duration of illness. CONCLUSION: The ABCA7 mRNA expression level in peripheral blood may be a marker for early stages of AD and disease progression regardless of rs3764650 and the methylation rate of its promoter.

7-Ketocholesterol is increased in the plasma of X-ALD patients and induces peroxisomal modifications in microglial cells: Potential roles of 7-ketocholesterol in the pathophysiology of X-ALD.

X-linked adrenoleukodystrophy (X-ALD) is a genetic disorder induced by a mutation in the ABCD1 gene, which causes the accumulation of very long-chain fatty acids in tissue and plasma. Oxidative stress may be a hallmark of X-ALD. In the plasma of X-ALD patients with different forms of the disease, characterized by high levels of C24:0 and C26:0, we observed the presence of oxidative stress revealed by decreased levels of GSH, α-tocopherol, and docosahexaenoic acid (DHA). We showed that oxidative stress caused the oxidation of cholesterol and linoleic acid, leading to the formation of cholesterol oxide derivatives oxidized at C7 (7-ketocholesterol (7KC), 7ß-hydroxycholesterol (7ß-OHC), and 7α-hydroxycholesrol (7α-OHC)) and of 9- and 13-hydroxyoctadecadienoic acids (9-HODE, 13-HODE), respectively. High levels of 7KC, 7ß-OHC, 7α-OHC, 9-HODE and 13-HODE were found. As 7KC induces oxidative stress, inflammation and cell death, which could play key roles in the development of X-ALD, the impact of 7KC on the peroxisomal status was determined in microglial BV-2 cells. Indeed, environmental stress factors such as 7KC could exacerbate peroxisomal dysfunctions in microglial cells and thus determine the progression of the disease. 7KC induces oxiapoptophagy in BV-2 cells: overproduction of H2O2 and O2-, presence of cleaved caspase-3 and PARP, nuclear condensation and/or fragmentation; elevated [LC3-II/LC3-I] ratio, increased p62 levels. 7KC also induces several peroxisomal modifications: decreased Abcd1, Abcd2, Abcd3, Acox1 and/or Mfp2 mRNA and protein levels, increased catalase activity and decreased Acox1-activity. However, the Pex14 level was unchanged. It is suggested that high levels of 7KC in X-ALD patients could foster generalized peroxisomal dysfunction in microglial cells, which could in turn intensify brain damage.

What is the acceptable hemolysis index for the measurements of plasma potassium, LDH and AST?

Hemolysis is a cause of variability in test results for plasma potassium, LDH and AST and is a non-negligible part of measurement uncertainty. However, allowable levels of hemolysis provided by reagent suppliers take neither analytical variability (trueness and precision) nor the measurand into account. Using a calibration range of hemolysis, we measured the plasma concentrations of potassium, LDH and AST, and hemolysis indices with a Cobas C501 analyzer (Roche Diagnostics(®), Meylan, France). Based on the allowable total error (according to Ricós et al.) and the expanded measurement uncertainty equation we calculated the maximum allowable bias for two concentrations of each measurand. Finally, we determined the allowable hemolysis indices for all three measurands. We observed a linear relationship between the observed increases of concentration and hemolysis indices. The LDH measurement was the most sensitive to hemolysis, followed by AST and potassium measurements. The determination of the allowable hemolysis index depends on the targeted measurand, its concentration and the chosen level of requirement of allowable total error.

A Personalized Approach to Biological Therapy Using Prediction of Clinical Response Based on MRP8/14 Serum Complex Levels in Rheumatoid Arthritis Patients.

OBJECTIVES: Measurement of MRP8/14 serum levels has shown potential in predicting clinical response to different biological agents in rheumatoid arthritis (RA). We aimed to develop a treatment algorithm based on a prediction score using MRP8/14 measurements and clinical parameters predictive for response to different biological agents. METHODS: Baseline serum levels of MRP8/14 were measured in 170 patients starting treatment with infliximab, adalimumab or rituximab. We used logistic regression analysis to develop a predictive score for clinical response at 16 weeks. MRP8/14 levels along with clinical variables at baseline were investigated. We also investigated how the predictive effect of MRP8/14 was modified by drug type. A treatment algorithm was developed based on categorizing the expected response per drug type as high, intermediate or low for each patient and optimal treatment was defined. Finally, we present the utility of using this treatment algorithm in clinical practice. RESULTS: The probability of response increased with higher baseline MRP8/14 complex levels (OR = 1.39), differentially between the TNF-blockers and rituximab (OR of interaction term = 0.78), and also increased with higher DAS28 at baseline (OR = 1.28). Rheumatoid factor positivity, functional disability (a higher HAQ), and previous use of a TNF-inhibitor decreased the probability of response. Based on the treatment algorithm 80 patients would have been recommended for anti-TNF treatment, 8 for rituximab, 13 for another biological treatment (other than TNFi or rituximab) and for 69 no recommendation was made. The predicted response rates matched the observed response in the cohort well. On group level the predicted response based on the algorithm resulted in a modest 10% higher response rate in our cohort with much higher differences in response probability in individual patients treated contrary to treatment recommendation. CONCLUSIONS: Prediction of response using MRP8/14 levels along with clinical predictors has potential in personalizing treatment for RA patients starting biological anti-rheumatic treatment, and might increase cost-effectiveness.

Common variants in ABCA7 and MS4A6A are associated with cortical and hippocampal atrophy.

The precise physiologic function of many of the recently discovered Alzheimer's disease risk variants remains unknown. The downstream effects of genetic variants remain largely unexplored. We studied the relationship between the top 10 non-APOE genes with cortical and hippocampal atrophy as markers of neurodegeneration using 1.5T magnetic resonance imaging, 1-million single nucleotide polymorphism Illumina Human Omni-Quad array and Illumina Human BeadChip peripheral blood expression array data on 50 cognitively normal and 98 mild cognitive impairment subjects. After explicit matching of cortical and hippocampal morphology, we computed in 3D, the cortical thickness and hippocampal radial distance measures for each participant. Associations between the top 10 non-APOE genome-wide hits and neurodegeneration were explored using linear regression. Map-wise statistical significance was determined with permutations using threshold of p < 0.01. MS4A6A rs610932 and ABCA7 rs3764650 demonstrated significant associations with cortical and hippocampal atrophy. Exploratory MS4A6A and ABCA7 peripheral blood expression analyses revealed a similar pattern of associations with cortical neurodegeneration. To our knowledge, this is the first report of the effect of ABCA7 and MS4A6A on neurodegeneration.

Serum myeloid-related protein 8/14 in minimal change- and glomerulonephritis-related nephrotic syndrome.

BACKGROUND: Myeloid-related protein 8/14 (MRP8/14) forms stable heterodimers and is the major calcium-binding protein secreted by activated granulocytes and monocytes. We evaluated whether serum MRP8/14 level is a useful indicator for a differential diagnosis of glomerulonephritis (GN)- and minimal change disease (MC)- related nephrotic syndrome (NS). METHODS: Serum MRP8/14 complex was evaluated in 37 NS patients with MC or GN. These patients were divided into two groups. Group 1 consisted of 13 NS patients with MC, and group 2 consisted of 24 NS patients with GN. Group 2 was further divided into four subgroups: IgA nephropathy (IgAN; n = 5), Henoch-Schönlein purpura nephritis (HSPN; n = 6), focal segmental glomerulosclerosis (FSGS; n = 12), and acute GN Poststreptococcal acute glomeruloNephritis (PSAGN; n = 1). RESULTS: The clinical manifestations, laboratory findings, serum MRP8/14 level, and renal accumulation of MRP8 were investigated for each group. No significant inter-group differences were observed for serum total protein, serum albumin, or blood urea nitrogen and urinary protein excretions. Mean serum MRP8/14 in the IgAN, HSPN, FSGS, and PSAGN groups was higher than in group 1. Further, the mean glomerular and interstitial MRP8 staining scores in the IgAN, HSPN, and PSAGN groups were higher than in group 1. CONCLUSIONS: Serum MRP8/14 level may be a useful indicator for differential diagnosis between GN- and MC- related NS.