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bioRxiv · 10.1101/2021.05.28.446155

Digital PCR to quantify ChAdOx1 nCoV-19 copies in blood and tissues

Badbaran, A.·Mailer, R.·Dahlke, C.·Woens, J.·Fathi, A.·Mellinghoff, S. C.·Renne, T.·Addo, M. M.·Riecken, K.·Fehse, B.
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Abstract

Vaccination with the adenoviral-vector based Astra Zeneca ChAdOx1 nCov-19 vaccine is efficient and safe. However, in rare cases vaccinated individuals developed life-threatening thrombotic complications, including thrombosis in cerebral sinus and splanchnic veins. Monitoring of the applied vector in vivo represents an important precondition to study the molecular mechanisms underlying vaccine-driven adverse effects now referred to as vaccine-induced immune thrombotic thrombocytopenia (VITT). We previously have shown that digital PCR is an excellent tool to quantify transgene copies in vivo. Here we present a highly sensitive digital PCR for in-situ quantification of ChAdOx1 nCoV-19 copies. Using this method, we quantified vector copies in human serum 24, 72 and 168 hours post vaccination, and in a variety of murine tissues in an experimental vaccination model 30 minutes post injection. We describe a method for high-sensitivity quantitative detection of ChAdOx1 nCoV-19 with possible implications to elucidate the mechanisms of severe ChAdOx1 nCov-19 vaccine complications.

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Badbaran, A., Mailer, R., Dahlke, C., Woens, J., Fathi, A., Mellinghoff, S. C., Renne, T., Addo, M. M., Riecken, K., Fehse, B.. 2021-05-28. Digital PCR to quantify ChAdOx1 nCoV-19 copies in blood and tissues. https://doi.org/10.1101/2021.05.28.446155

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