| 1. |
- Emami Khoonsari, Payam, et al.
(författare)
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Analysis of the Cerebrospinal Fluid Proteome in Alzheimer's Disease
- 2016
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 11:3
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Tidskriftsartikel (refereegranskat)abstract
- Alzheimer's disease is a neurodegenerative disorder accounting for more than 50% of cases of dementia. Diagnosis of Alzheimer's disease relies on cognitive tests and analysis of amyloid beta, protein tau, and hyperphosphorylated tau in cerebrospinal fluid. Although these markers provide relatively high sensitivity and specificity for early disease detection, they are not suitable for monitor of disease progression. In the present study, we used label-free shotgun mass spectrometry to analyse the cerebrospinal fluid proteome of Alzheimer's disease patients and non-demented controls to identify potential biomarkers for Alzheimer's disease. We processed the data using five programs (DecyderMS, Maxquant, OpenMS, PEAKS, and Sieve) and compared their results by means of reproducibility and peptide identification, including three different normalization methods. After depletion of high abundant proteins we found that Alzheimer's disease patients had lower fraction of low-abundance proteins in cerebrospinal fluid compared to healthy controls (p<0.05). Consequently, global normalization was found to be less accurate compared to using spiked-in chicken ovalbumin for normalization. In addition, we determined that Sieve and OpenMS resulted in the highest reproducibility and PEAKS was the programs with the highest identification performance. Finally, we successfully verified significantly lower levels (p<0.05) of eight proteins (A2GL, APOM, C1QB, C1QC, C1S, FBLN3, PTPRZ, and SEZ6) in Alzheimer's disease compared to controls using an antibody-based detection method. These proteins are involved in different biological roles spanning from cell adhesion and migration, to regulation of the synapse and the immune system.
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| 2. |
- Lönnberg, Maria, et al.
(författare)
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Patients with anaemia can shift from kidney to liver production of erythropoietin as shown by glycoform analysis
- 2013
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Ingår i: Journal of Pharmaceutical and Biomedical Analysis. - : Elsevier BV. - 0731-7085 .- 1873-264X. ; 81-82, s. 187-192
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Tidskriftsartikel (refereegranskat)abstract
- The primary production site of erythropoietin (EPO) is shifted from the liver to the kidney shortly after birth. Under conditions of lost or reduced kidney production, it is valuable to measure the production capacity of the liver. However, there is a lack of urine or serum based methods that can distinguish endogenous EPO produced in different cell types. Here is presented a method based on chromatographic interaction with the lectin wheat germ agglutinin (WGA) that can distinguish presumably liver-produced EPO, found in anaemic patients receiving epoetin and darbepoetin, from kidney-produced EPO found in healthy individuals.All the tested samples from haemodialysis patients with end-stage renal disease showed a presence of liver EPO. In some samples, the liver-produced EPO made up 90–100% of total EPO at a concentration of 8–10 ng/L in urine, which indicates that the liver has a quite high production capacity, although not adequate for the degree of anaemia.This glycoform analysis has made it possible to affirm that some anaemic patients can increase their liver-production of EPO. The use of such a method can give better insight into the regulation of non-renal endogenous EPO production, a potential source of EPO intended to replace administration of exogenous EPO.
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| 3. |
- Lönnberg, Maria, et al.
(författare)
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Rapid detection of erythropoiesis-stimulating agents in urine and serum
- 2012
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Ingår i: Analytical Biochemistry. - : Elsevier BV. - 0003-2697 .- 1096-0309. ; 420:2, s. 101-114
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Tidskriftsartikel (refereegranskat)abstract
- A rapid and easy-to-use test kit, EPO WGA MAIIA, which can be used for distinguishing various endogenous human erythropoietins (hEPO) and several recombinant hEPOs and EPO analogues, has been evaluated. The test is based on chromatographic separation of the glycosylated isoforms of EPO using wheat germ agglutinin (WGA), and a sensitive immunoassay utilizing anti-EPO carbon black nanostrings and image scanning for quantification. All the reactions take place along the porous layer of a lateral flow micro-column containing WGA and anti-EPO zones. The presence of molecules resembling hEPO, like Mircera, was detected by the aberrant affinity interaction with the antibody zone on the strip. It was possible to distinguish nine recombinant hEPO expressed in hamster and human cell-lines, and also Aranesp and Mircera, from endogenous urine hEPO. The required amount of EPO in the samples, a few pg, is very low compared to other methods for EPO isoform identification. This EPO isoform determination method opens the possibility to monitor recombinant EPO therapy for clinical research and seems to be a valuable candidate to the arsenal of EPO doping control tests.
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| 4. |
- Bailly-Chouriberry, Ludovic, et al.
(författare)
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A new analytical method based on anti-EPO monolith column and LC-FAIMS-MS/MS for the detection of rHuEPOs in horse plasma and urine samples
- 2012
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Ingår i: The Analyst. - 0003-2654 .- 1364-5528. ; 137:10, s. 2445-2453
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Tidskriftsartikel (refereegranskat)abstract
- Recombinant human erythropoietin (rHuEPO) is a 30-34 kDa glycoprotein banned by the racing authorities. For some years this molecule has been detected in race horses in USA and in Europe, and even in racing camels. Although direct methods to differentiate horse endogenous EPO and rHuEPO have been developed either by LC-MS/MS or by isoelectric focusing (IEF) with double-blotting, the short confirmation time of such prohibited hormone in plasma remains a problem for horseracing doping control laboratories. In order to improve the rHuEPOs confirmation process in horse plasma or urine in terms of reliability and delay, a small anti-EPO monolith membrane contained in a disposable column (anti-EPO monolith column) has been successfully used and validated (n = 10). This new sample preparation, combined with LC-FAIMS-MS/MS, has been performed on plasma and urine samples collected from one horse which received an Eprex[registered sign] treatment during six consecutive days and a second one with a single injection of Aranesp[registered sign]. This inventive technology allowed the possibility to confirm the presence of rHuEPO within one day with a limit of detection validated for both urine and plasma at 250 pg mL-1 by means of a disposable, ready to use immunoaffinity column. The lower limit of detection (LLOD) obtained for each matrix was 100 pg mL-1. These results provide an important improvement for rHuEPO doping control in horseracing especially the possibility to confirm these banned molecules in both matrices, urine and plasma, with a confidence of two specific target peptides.
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| 5. |
- Dehnes, Yvette, et al.
(författare)
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Erythropoietin (EPO) immunoaffinity columns-A powerful tool for purifying EPO and its recombinant analogues
- 2010
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Ingår i: Journal of Pharmaceutical and Biomedical Analysis. - : Elsevier BV. - 0731-7085 .- 1873-264X. ; 53:4, s. 1028-1032
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Tidskriftsartikel (refereegranskat)abstract
- The sample preparation method preceding the urinary erythropoietin (EPO) doping test is based on several concentration and ultrafiltration steps. In order to improve the quality of isoelectric focusing (IEF) gel results and therefore, the sensitivity of the EPO test, new sample preparation methods relying on affinity purification were recently proposed. This article focuses on the evaluation and validation of disposable immunoaffinity columns targeting both endogenous and recombinant EPO molecules in two World Anti-Doping Agency (WADA) accredited anti-doping laboratories. The use of the columns improved the resolution of the IEF profiles considerably when compared with the classical ultrafiltration method, and the columns' ability to ensure the isoform integrity of the endogenous and exogenous EPO molecules was confirmed. Immunoaffinity columns constitute therefore a potent and reliable tool for the preparation of urine samples and their use will significantly improve the sensitivity and specificity of the actual urinary EPO test.
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| 6. |
- Franco Fraguas, L, et al.
(författare)
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Lectin affinity chromatography as a tool to differentiate endogenous and recombinant erythropoietins
- 2008
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Ingår i: Journal of Chromatography A. - : Elsevier BV. - 0021-9673 .- 1873-3778. ; 1212:1-2, s. 82-88
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Tidskriftsartikel (refereegranskat)abstract
- This work exploits the combination of the lectin affinity chromatography (LAC) with an ultra-sensitive immunochromatographic assay to differentiate several types of erythropoietin (EPO). The chromatographic behaviours of different commercial types of recombinant human EPO (rhEPO), EPO analogues (Aranesp) and urine human EPO (uhEPO) from healthy individuals on eight lectin-Sepharose columns, have been worked out. Results show that when using wheat germ agglutinin (WGA)-Sepharose columns, a careful desorption regime starting with very low concentration (2mM) of the competitive sugar N-acetylglucosamine (GlcNAc) makes it possible to efficiently distinguish endogenous EPO from recombinant EPO and EPO analogues.
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| 7. |
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| 8. |
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| 9. |
- Lönnberg, Maria, et al.
(författare)
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Chromatographic performance of a thin microporous bed of nitrocellulose
- 2001
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Ingår i: JOURNAL OF CHROMATOGRAPHY B. - 0378-4347. ; 763:1-2, s. 107-120
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Tidskriftsartikel (refereegranskat)abstract
- Chromatography along thin (125 mum) porous beds of nitrocellulose, layered on top of an polyester backing, shows good separation efficiency with plate heights of 10-20 mum. Flow is controlled by capillary forces and shows low rate variations between the i
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| 10. |
- Lönnberg, Maria, et al.
(författare)
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Detection of EPO injections using a rapid lateral flow isoform test
- 2013
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Ingår i: Analytical and Bioanalytical Chemistry. - : Springer Science and Business Media LLC. - 1618-2642 .- 1618-2650. ; 405:30, s. 9685-9691
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Tidskriftsartikel (refereegranskat)abstract
- Misuse of recombinant human erythropoietin (rhEPO) is a major concern in competitive sports, and the implementation of tests allowing for higher detection rates than what current tests are capable of is required. In this study, a novel lateral flow EPO isoform test kit, EPO WGA MAIIA, is evaluated on the basis of plasma and urine samples obtained from eight healthy males in connection with a 28-day rhEPO injection period. rhEPO was injected every other day during the first 14 days of the study, and the method proved to be 100 % effective in detecting rhEPO in the concomitantly obtained samples. Seven days after the last injection, three positive (>99.99 % confidence limit (CL)) subjects were found. When using 99 % CL as the cut-off limit, six of the eight subjects (75 %) were found to be suspected of doping. Samples obtained 14 and 21 days after the last injection showed no detectable trace of rhEPO. A previous study using indirect methods to determine EPO doping on the same samples indicated only that two of the subjects had suspicious values 7-21 days after the last injection. We propose implementing the easy to-use EPO WGA MAIIA test as an initial screening procedure in anti-doping work to (1) increase the detection rate of potential rhEPO doping athletes and (2) allow for a 10- to 20-fold higher analytical rate than what is possible today.
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