@article{Michalik_Siegerist_Palankar_Franzke_Schindler_Reder_Seifert_Cammann_Wesche_Steil_Hentschker_Gesell-Salazar_Reisinger_Beer_Endlich_Greinacher_Völker_2022, place={Pavia, Italy}, title={Comparative analysis of ChAdOx1 nCoV-19 and Ad26.COV2.S SARS-CoV-2 vector vaccines}, volume={107}, url={https://haematologica.org/article/view/haematol.2021.280154}, DOI={10.3324/haematol.2021.280154}, abstractNote={<p>Vector-based SARS-CoV-2 vaccines have been associated with vaccine- induced thrombosis with thrombocytopenia syndrome (VITT/TTS), but the causative factors are still unresolved. We comprehensively analyzed the ChAdOx1 nCoV-19 (AstraZeneca) and Ad26.COV2.S (Johnson and Johnson) vaccines. ChAdOx1 nCoV-19 contains significant amounts of host cell protein impurities, including functionally active proteasomes, and adenoviral proteins. A much smaller amount of impurities was found in Ad26.COV2.S. Platelet factor 4 formed complexes with ChAdOx1 nCoV-19 constituents, but not with purified virions from ChAdOx1 nCoV-19 or with Ad26.COV2.S. Vascular hyperpermeability was induced by ChAdOx nCoV-19 but not by Ad26.COV2.S. These differences in impurities together with EDTAinduced capillary leakage might contribute to the higher incidence rate of VITT associated with ChAdOx1 nCoV-19 compared to Ad26.COV2.S.</p&gt;}, number={4}, journal={Haematologica}, author={Michalik, Stephan and Siegerist, Florian and Palankar, Raghavendra and Franzke, Kati and Schindler, Maximilian and Reder, Alexander and Seifert, Ulrike and Cammann, Clemens and Wesche, Jan and Steil, Leif and Hentschker, Christian and Gesell-Salazar, Manuela and Reisinger, Emil and Beer, Martin and Endlich, Nicole and Greinacher, Andreas and Völker, Uwe}, year={2022}, month={Apr.}, pages={947-957} }