Effect of beta propiolactone viral inactivation on alpha1 antitrypsin values

Abstract

Aims: α1 Antitrypsin was undetectable in several patient samples treated with 0.5% β propiolactone, which was used as a virucidal agent. This study was designed to confirm β propiolactone as the cause and determine why it might have such an effect. Methods: Volumes of 0, 5, 10, and 20 µl of β propiolactone were added to 2 ml aliquots of serum to make final concentrations of 0%, 0.25%, 0.5%, and 1% of β propiolactone. α1 Antitrypsin concentrations and the pH were measured at different time intervals. The effects of adding buffer before the addition of β propiolactone, NaOH after β propiolactone, and 6M HCl instead of β propiolactone were also measured.Results: The addition of β propiolactone to a volunteer's serum showed a fall in both α1 antitrypsin values and pH with increasing time and concentration of β propiolactone. This effect was also seen when adding HCl, but was partially prevented by buffering the serum or adding NaOH. Conclusions: These results suggest that it is the acidity of the degradation products of β propiolactone that is responsible for the fall in α1 antitrypsin values. This fall in α1 antitrypsin values was dependent on the concentration of β propiolactone used and the length of time before the test was performed. The effect of β propiolactone on laboratory tests should be re-evaluated, with attention being paid to sample pH, storage time, and storage temperature.

Sample-Treatment with the Virucidal β-Propiolactone Does Not Preclude Analysis by Large Panel Affinity Proteomics, Including the Discovery of Biomarker Candidates

“…These findings, however, appear not generally reproducible or generalizable to all proteins. Although α1-antitrypsin (AAT) levels were previously reported to be unchanged by BPL treatment, this result was not reproduced in other work 5 investigating the impact of sample pH, incubation time, and temperature on apparent protein abundance. A decrease in measured AAT abundance was observed to correlate with pH, time, and BPL concentration.…”

Plasma-treatment with the virucidal beta-propiolactone does not preclude analysis by large panel affinity proteomics, including the discovery of biomarker candidates

“…These findings, however, appear not generally reproducible or generalizable to all proteins. Although, α1antitrypsin (AAT) levels were previously reported to be unchanged by BPL-treatment, this result was not reproduced in other work [5], which investigated the impact of sample pH, incubation time and temperature on apparent protein abundance. A decrease in measured AAT abundance was observed to correlate with pH, time and BPL concentration.…”