Bei Patienten mit ST-Strecken-Elevations-Myokardinfarkt (STEMI) ist die direkte intrakoronare Bolusverabreichung des Glykoprotein-IIb/IIIa-Rezeptorantagonist Abciximab, im Gegensatz zur periphervenösen Bolusinjektion, mit einer Reduktion von Infarktgröße und mikrovaskulärer Obstruktion sowie mit einem höheren Anteil geretteten Myokards assoziiert, vermutlich ausgelöst durch eine höhere lokale Arzneimittelkonzentration und der dadurch gesteigerten Hemmung der Plättcheninhibition. Ziel der Arbeit war es herauszufinden, ob es Unterschiede gibt bezüglich der GP-IIb/IIIa Rezeptorbesetzung und der Thrombozyteninhibition im venösen Koronarblut, welches kurz nach intrakoronarer oder periphervenöser Abciximab-Bolusinjektion entnommen wurde. Dafür wurden bei 16 Patienten mit akutem STEMI vor und unmittelbar nach der Gabe eines Abciximab-Bolus sowie nach 30 Minuten Blutproben aus dem Korornarsinus entnommen. Jeweils 8 Patienten erhielten entweder den Bolus intrakoronar oder peripher venös verabreicht. Sofort nach der Bolusapplikation war die Rezeptorbesetzung im venösem Koronarblut signifikant höher bei Patienten, die einen direkten intrakoronaren Bolus erhalten hatten, im Vergleich mit Patienten mit peripherer Bolusadministration (intrakorornarer Bolus: 93.5% [IQR 92.7–95.4], intravenöser Bolus: 74.0% [IQR 17.6–94.0], p = 0.04). Das Ausmaß der Plättcheninhibition war früh nach Bolusgabe ebenso deutlich höher bei intrakoronarer anstatt intravenöser Bolusapplikation. In der späten Blutentnahme 30 Minuten nach der Bolusapplikation konnten keine signifikanten Unterschiede zwischen beiden untersuchten Gruppen, weder bezüglich der GP-IIb/IIIa Rezeptorbesetzung noch der Thrombozytenaggregationshemmung, gefunden werden. Zusammenfassend kann man sagen, dass die direkte intrakoronare Bolusapplikation akut in eine höhere lokale Inhibition der Thrombozytenfunktion und einem größeren Anteil an geblockten GP-IIb/IIIa Rezeptoren im Vergleich zur peripher venösen Bolusinjektion resultiert. Limitierend muss die geringe Fallzahl erwähnt werden. Die Ergebnisse sollten deshalb zurückhaltend interpretiert werden.

Platelet products have a short shelf life (5 to 7 days) owing in part to the deterioration of the quality of platelets stored at 22°C. This creates significant inventory challenges, and blood banks may suffer shortages and high wastage as a result. Proteomics offers a global quantitative approach to investigate changes occurring in stored blood products. These data sets can identify processes leading to storage-associated losses of blood component quality such as the platelet storage lesion (PSL). Changes to the platelet proteome between days 1 and 7 of storage were analysed with 3 complementary proteomic approaches with final mass spectrometric (MS) analysis: 2-dimensional (2D) gel electrophoresis/differential gel electrophoresis (DIGE), isobaric tagging for relative and absolute quantification (iTRAQ), and isotope-coded affinity tagging (ICAT). Although proteomics analyses identified many storage-associated protein changes, these varied significantly by method suggesting that a combination of protein-centric (2D gel or DIGE) and peptide-centric (iTRAQ or ICAT) approaches is necessary to acquire the most informative data. Validation of the proteomics results by western blotting, flow cytometry, quantitative real-time polymerase chain reaction (qRT PCR) and ³ٰ⁵S-methionine incorporation confirmed that platelets are capable of synthesising biologically relevant proteins ex vivo throughout a 10-day storage period with particularly long-lived mRNA (half-life of approximately 2.4 days), and has provided the first evidence for one of the mechanisms of the PSL. The development of an ³ٰ⁵Smethionine assay has since shown that stored human blood platelets incorporate ³ٰ⁵S-methionine at a rate that is proportional to time and substrate concentration, and is slower for freshly drawn platelets than those stored in pooled buffy coat derived units for 10 days. More interesting still are the observations that the overall ³ٰ⁵S-methionine incorporation rate was higher in pooled buffy coat platelet units versus freshly drawn platelets, that this rate increased upon agonist exposure in both, and that day 8 platelets showed significantly greater total protein translation than on days 2,3,7 and 10 of storage. This may be indicative of translational regulation of the platelet proteome during storage and upon activation. Translational control is a consequence of remarkable cellular specialisation and precise biochemical pathways which, in the case of platelets, may lead to storage-associated losses of blood component quality and must be understood if platelet storage times are to be extended.

Platelet products have a short shelf life (5 to 7 days) owing in part to the deterioration of the quality of platelets stored at 22°C. This creates significant inventory challenges, and blood banks may suffer shortages and high wastage as a result. Proteomics offers a global quantitative approach to investigate changes occurring in stored blood products. These data sets can identify processes leading to storage-associated losses of blood component quality such as the platelet storage lesion (PSL). Changes to the platelet proteome between days 1 and 7 of storage were analysed with 3 complementary proteomic approaches with final mass spectrometric (MS) analysis: 2-dimensional (2D) gel electrophoresis/differential gel electrophoresis (DIGE), isobaric tagging for relative and absolute quantification (iTRAQ), and isotope-coded affinity tagging (ICAT). Although proteomics analyses identified many storage-associated protein changes, these varied significantly by method suggesting that a combination of protein-centric (2D gel or DIGE) and peptide-centric (iTRAQ or ICAT) approaches is necessary to acquire the most informative data. Validation of the proteomics results by western blotting, flow cytometry, quantitative real-time polymerase chain reaction (qRT PCR) and ³ٰ⁵S-methionine incorporation confirmed that platelets are capable of synthesising biologically relevant proteins ex vivo throughout a 10-day storage period with particularly long-lived mRNA (half-life of approximately 2.4 days), and has provided the first evidence for one of the mechanisms of the PSL. The development of an ³ٰ⁵Smethionine assay has since shown that stored human blood platelets incorporate ³ٰ⁵S-methionine at a rate that is proportional to time and substrate concentration, and is slower for freshly drawn platelets than those stored in pooled buffy coat derived units for 10 days. More interesting still are the observations that the overall ³ٰ⁵S-methionine incorporation rate was higher in pooled buffy coat platelet units versus freshly drawn platelets, that this rate increased upon agonist exposure in both, and that day 8 platelets showed significantly greater total protein translation than on days 2,3,7 and 10 of storage. This may be indicative of translational regulation of the platelet proteome during storage and upon activation. Translational control is a consequence of remarkable cellular specialisation and precise biochemical pathways which, in the case of platelets, may lead to storage-associated losses of blood component quality and must be understood if platelet storage times are to be extended.

Platelet products have a short shelf life (5 to 7 days) owing in part to the deterioration of the quality of platelets stored at 22°C. This creates significant inventory challenges, and blood banks may suffer shortages and high wastage as a result. Proteomics offers a global quantitative approach to investigate changes occurring in stored blood products. These data sets can identify processes leading to storage-associated losses of blood component quality such as the platelet storage lesion (PSL). Changes to the platelet proteome between days 1 and 7 of storage were analysed with 3 complementary proteomic approaches with final mass spectrometric (MS) analysis: 2-dimensional (2D) gel electrophoresis/differential gel electrophoresis (DIGE), isobaric tagging for relative and absolute quantification (iTRAQ), and isotope-coded affinity tagging (ICAT). Although proteomics analyses identified many storage-associated protein changes, these varied significantly by method suggesting that a combination of protein-centric (2D gel or DIGE) and peptide-centric (iTRAQ or ICAT) approaches is necessary to acquire the most informative data. Validation of the proteomics results by western blotting, flow cytometry, quantitative real-time polymerase chain reaction (qRT PCR) and ³ٰ⁵S-methionine incorporation confirmed that platelets are capable of synthesising biologically relevant proteins ex vivo throughout a 10-day storage period with particularly long-lived mRNA (half-life of approximately 2.4 days), and has provided the first evidence for one of the mechanisms of the PSL. The development of an ³ٰ⁵Smethionine assay has since shown that stored human blood platelets incorporate ³ٰ⁵S-methionine at a rate that is proportional to time and substrate concentration, and is slower for freshly drawn platelets than those stored in pooled buffy coat derived units for 10 days. More interesting still are the observations that the overall ³ٰ⁵S-methionine incorporation rate was higher in pooled buffy coat platelet units versus freshly drawn platelets, that this rate increased upon agonist exposure in both, and that day 8 platelets showed significantly greater total protein translation than on days 2,3,7 and 10 of storage. This may be indicative of translational regulation of the platelet proteome during storage and upon activation. Translational control is a consequence of remarkable cellular specialisation and precise biochemical pathways which, in the case of platelets, may lead to storage-associated losses of blood component quality and must be understood if platelet storage times are to be extended. / Medicine, Faculty of / Biochemistry and Molecular Biology, Department of / Graduate

Bei Patienten mit ST-Strecken-Elevations-Myokardinfarkt (STEMI) ist die direkte intrakoronare Bolusverabreichung des Glykoprotein-IIb/IIIa-Rezeptorantagonist Abciximab, im Gegensatz zur periphervenösen Bolusinjektion, mit einer Reduktion von Infarktgröße und mikrovaskulärer Obstruktion sowie mit einem höheren Anteil geretteten Myokards assoziiert, vermutlich ausgelöst durch eine höhere lokale Arzneimittelkonzentration und der dadurch gesteigerten Hemmung der Plättcheninhibition. Ziel der Arbeit war es herauszufinden, ob es Unterschiede gibt bezüglich der GP-IIb/IIIa Rezeptorbesetzung und der Thrombozyteninhibition im venösen Koronarblut, welches kurz nach intrakoronarer oder periphervenöser Abciximab-Bolusinjektion entnommen wurde. Dafür wurden bei 16 Patienten mit akutem STEMI vor und unmittelbar nach der Gabe eines Abciximab-Bolus sowie nach 30 Minuten Blutproben aus dem Korornarsinus entnommen. Jeweils 8 Patienten erhielten entweder den Bolus intrakoronar oder peripher venös verabreicht. Sofort nach der Bolusapplikation war die Rezeptorbesetzung im venösem Koronarblut signifikant höher bei Patienten, die einen direkten intrakoronaren Bolus erhalten hatten, im Vergleich mit Patienten mit peripherer Bolusadministration (intrakorornarer Bolus: 93.5% [IQR 92.7–95.4], intravenöser Bolus: 74.0% [IQR 17.6–94.0], p = 0.04). Das Ausmaß der Plättcheninhibition war früh nach Bolusgabe ebenso deutlich höher bei intrakoronarer anstatt intravenöser Bolusapplikation. In der späten Blutentnahme 30 Minuten nach der Bolusapplikation konnten keine signifikanten Unterschiede zwischen beiden untersuchten Gruppen, weder bezüglich der GP-IIb/IIIa Rezeptorbesetzung noch der Thrombozytenaggregationshemmung, gefunden werden. Zusammenfassend kann man sagen, dass die direkte intrakoronare Bolusapplikation akut in eine höhere lokale Inhibition der Thrombozytenfunktion und einem größeren Anteil an geblockten GP-IIb/IIIa Rezeptoren im Vergleich zur peripher venösen Bolusinjektion resultiert. Limitierend muss die geringe Fallzahl erwähnt werden. Die Ergebnisse sollten deshalb zurückhaltend interpretiert werden.