Whole Blood C-reactive Protein Research Articles

D-dimer, C-reactive protein and matrix metalloproteinase 9 for prediction of type A aortic dissection patient survival.

Acute type A aortic dissection (ATAAD) is a life-threatening condition requiring prompt diagnosis and treatment. Surgery is an effective treatment for ATAAD, but the in-hospital mortality rate in the 30day perioperative period is still as high as 9-30%. It is critical to identify biological factors for preoperative assessment of post-operative survival in patients with ATAAD. This is a retrospective study, investigating the association of combined measurements of d-dimer, C-reactive protein (CRP), and matrix metalloproteinase 9 (MMP9) for 1year of survival in patients with ATAAD. Data from 247 patients who underwent surgery were analysed, including 89 patients who did not survive and 158 patients who survived within 1year after surgery. Pearson's correlation analysis was carried out to determine the correlations between CRP in whole blood, d-dimer in plasma, and CRP in whole blood. Receiver operating characteristic (ROC) analysis was used to analyse the value of preoperative whole blood CRP, plasma d-dimer, and serum MMP9 concentration and the combined detection model in predicting death of patients with ATAAD. Deceased patients with ATAAD exhibited higher age, hypertension prevalence, systolic blood pressure, white blood cell count, whole blood CRP, plasma d-dimer, and serum MMP9 levels compared with survivors. Preoperative CRP, d-dimer, and MMP9 levels were significantly higher in patients with ATAAD compared with healthy controls. Positive correlations were observed between CRP and d-dimer, CRP and MMP9, and d-dimer and MMP9 in patients with ATAAD. ROC analysis showed that the combined detection model of CRP, d-dimer, and MMP9 had the highest predictive value for 1year of survival (area under the curve=0.88). Combined measurement of CRP, d-dimer, and MMP9 is associated with 1year of survival in patients with ATAAD.

An array-based electrochemical magneto-immunosensor for early neonatal sepsis diagnostic: Fast and accurate determination of C-reactive protein in whole blood and plasma samples

An array-based electrochemical magneto-immunosensor (a-EMI) constituted by eight screen-printed carbon electrodes is proposed for the determination of C-reactive protein (CRP). Remarkably, the analytical usefulness of the approach was demonstrated not only by analyzing whole blood samples, but plasma ones from newborns with suspicion of sepsis, which sample volume is hardly available.The a-EIM enabled the accurate determination of CRP in these unique samples (Er < 3%) with excellent intra (CV<4%, n=8) and inter-assays (CV<9%, n=8) precision, using only 5 µL of clinical sample, covering the sepsis diagnostic range and employing only 15 min for total assay. The electrode array enabled to work with up to 8 tailored dilutions simultaneously accordingly to the CRP clinical diagnostic range. It constitutes by itself a valuable advantage for speed and reliability improvements in the sample analysis and further sepsis diagnosis.These results non-only highly met the clinical needs for sepsis newborns diagnosis, but they opened new perspectives in low volumes-based diagnostics.

Use of a time-resolved immunofluorometric assay for determination of canine C-reactive protein concentrations in whole blood

To develop and validate a time-resolved immunofluorometric assay (TR-IFMA) for measurement of C-reactive protein (CRP) in canine whole blood. 12 healthy dogs and 35 dogs with inflammatory processes. CRP was isolated from acute-phase serum by affinity chromatography and used as a standard for calibration. Analytic and functional limit of detection and intra-assay and interassay precision were calculated. Accuracy was evaluated by recovery assays and by comparison with results of a commercial ELISA. Correlation between CRP concentrations in whole blood and corresponding plasma fractions was tested by use of TR-IFMA. Stability of blood samples at 4 degrees C was assessed during a 1-month period, and effects of anticoagulants were evaluated. Measurements of CRP in blood samples from 12 healthy dogs were compared with those of 35 dogs with inflammatory diseases. Analytic and functional limits of detection were 0.53 and 3.26 microg/mL, respectively. Intra-assay and interassay coefficients of variation varied between 2.1% to 8.9% and 8.0% to 12.3%, respectively. Mean recoveries of added CRP were 104% and 114%. Measurements of CRP by use of TR-IFMA and ELISA were highly correlated (R2 = 0.97). Measurements of CRP in whole blood and in corresponding plasma fractions by use of TR-IFMA were also highly correlated (R2 = 0.97). Neither storage nor use of anticoagulants disturbed measurement of CRP concentrations in whole blood. Concentrations of CRP in whole blood of dogs with inflammation were significantly higher than in healthy dogs. Determination of CRP concentrations in whole blood may provide a diagnostic test for inflammation in dogs.

Development of a point-of-care assay system for high-sensitivity C-reactive protein in whole blood

Background: C-reactive protein (CRP) is emerging as a potential risk predictor for future cardiovascular diseases (CVD). High sensitivity assays have been developed and applied for clinical purposes. Methods: The fluorescence immunochromatographic assay was employed to detect and quantify CRP in whole blood. It consisted of a fluorescence (FL) antibody detector buffer, a test strip housed in a disposable cartridge, and a laser fluorescence scanner. Whole blood sample was mixed with detector, loaded onto a cartridge, incubated for 10 min, and the concentration of CRP was measured in a laser fluorescence scanner. The linearity, limit of detection (LOD), and performance of new assay system was tested and evaluated. The comparability of assay was examined with an automated reference method. Results: With the new assay system, a reliable correlation of coefficient ( r) was obtained between the ratio value ( A T/ A C) and a concentration of CRP in samples. The linearity fell in the range of 0–10 mg/l of CRP, and the analytical detection limit was 0.133 mg/l of CRP. The mean recovery of the control was 105.2% in a working range. The precision of the intra- and inter-assay in a range of 0.5–6 mg/l was CVs <6% and <8%, respectively. The new fluorescence immunochromatographic assay system correlated well with a traditional immunoturbidimetric assay for quantification of CRP concentration ( r=0.955, N=90). Conclusion: The fluorescence immunochromatographic assay is fast, reliable, and a reproducible platform for point-of-care testing (POCT) of high-sensitive (hs)-CRP in whole blood.

Hydrodynamic guiding for addressing subsets of immobilized cells and molecules in microfluidic systems

BackgroundThe interest in microfluidics and surface patterning is increasing as the use of these technologies in diverse biomedical applications is substantiated. Controlled molecular and cellular surface patterning is a costly and time-consuming process. Methods for keeping multiple separate experimental conditions on a patterned area are, therefore, needed to amplify the amount of biological information that can be retrieved from a patterned surface area. We describe, in three examples of biomedical applications, how this can be achieved in an open microfluidic system, by hydrodynamically guiding sample fluid over biological molecules and living cells immobilized on a surface.ResultsA microfluidic format of a standard assay for cell-membrane integrity showed a fast and dose-dependent toxicity of saponin on mammalian cells. A model of the interactions of human mononuclear leukocytes and endothelial cells was established. By contrast to static adhesion assays, cell-cell adhesion in this dynamic model depended on cytokine-mediated activation of both endothelial and blood cells. The microfluidic system allowed the use of unprocessed blood as sample material, and a specific and fast immunoassay for measuring the concentration of C-reactive protein in whole blood was demonstrated.ConclusionThe use of hydrodynamic guiding made multiple and dynamic experimental conditions on a small surface area possible. The ability to change the direction of flow and produce two-dimensional grids can increase the number of reactions per surface area even further. The described microfluidic system is widely applicable, and can take advantage of surfaces produced by current and future techniques for patterning in the micro- and nanometer scale.

Ultrarapid, Ultrasensitive One-Step Kinetic Immunoassay for C-Reactive Protein (CRP) in Whole Blood Samples: Measurement of the Entire CRP Concentration Range with a Single Sample Dilution

Recently, measurement of very low concentrations of C-reactive protein (CRP) has gained popularity as a potential new means for predicting the risk of future cardiac complications. In this study, we demonstrate the feasibility of a kinetic, one-step microparticle assay for quantitative determination of extremely low and high CRP concentrations in the limited timeframe typical for point-of-care testing. A noncompetitive, kinetic CRP immunoassay was developed that uses individual, porous microparticles as the solid phase. The microparticles were covalently coated with a monoclonal capture antibody, and the monoclonal detection antibody was labeled with europium. The one-step binding reaction was stopped by washing after 2 min of incubation, and the fluorescence signal of individual particles was measured. The analytical detection limit (mean of zero calibrator + 3 SD) was 0.00016 mg/L CRP. Clinical samples were diluted 400-fold before assay to cover the CRP concentration range of 0.064-1200 mg/L. The assay correlated well with the Dade Behring N High Sensitivity CRP assay (for 0-10 mg/L, r = 0.969, S(y/x) = 0.68, n = 54; for 0-350 mg/L, r = 0.969, S(y/x) = 11.7, n = 100). The within- and between-run CVs based on calculated concentrations were, respectively, 9-16% and 14% at 0.11 mg/L, 4.5-12% and 8.2% at 4.2 mg/L, and 3.5-6.3% and 4.4% at 105 mg/L, with a CV <15% at 0.2 mg/L and above. Use of the kinetic microparticle approach combined with time-resolved fluorometry allows ultrasensitive quantification of CRP in whole blood in 2 min with a linear assay range spanning more than four orders of magnitude.

Rapid Immunometric Measurement of C-Reactive Protein in Whole Blood

We examined an instrument-free test for C-reactive protein (CRP) in whole blood. The NycoCard CRP Whole Blood test uses a cell-solubilizing dilution liquid, a membrane-bound antibody that binds CRP, and a gold-conjugated antibody for making visible the bound CRP. We obtained essentially identical dose-response curves in citrate-, heparin-, and EDTA-treated blood. CVs were 6.7-12.5% within series and 10.1-14.7% between series. The detection limit was 12 mg/L. Intralipid added to blood increased measured CRP by 10-20%, whereas no change was seen with added bilirubin, added serum amyloid P component, or the presence of rheumatoid factor. In 234 patients' blood samples the results of the NycoCard Whole Blood test correlated well (r = 0.96) with those of a turbidimetric serum method. The test allows reliable measurement of CRP from a small volume of whole blood (25 microL) without using expensive equipment; it should be useful for decentralized testing in hospital departments, emergency units, and primary health care centers.