Safety Assessment: a Comparative Analysis of Quantitative Content of Bacterial Endotoxins and Evaluation of Pyrogenicity of the Kazakhstan Vaccine QazCovid-in® against COVID-19.

We measured the levels of bacterial endotoxins in the bulk vaccine product (BVP) and finished vaccine QazCovid-in® and evaluated the effect of aluminum hydroxide (adjuvant) on the results of LAL test and pyrogenicity of samples in vivo (in rabbits receiving intravenous injection into the marginal ear vein). Administration of BVP with LPS resulted in a dose-dependent increase in body temperature in rabbits similar to that caused by LPS alone, which suggests that aluminum hydroxide in the vaccine did not affect the pyrogenic response in rabbits. Moreover, the LAL test showed that the aluminum hydroxide did not hinder LPS activity after serial dilution of samples.

[Genetic stability of the HA, NA, and NS genes of the recombinant vector virus Flu-NS1-124-Omp16 (H5N1) expressing the brucellar gene].

The recombinant strain Flu-NS1-124-Omp16 (H5N1) of the influenza virus expressing the brucellar Omp16 gene was constructed on the basis of the technology of reverse genetics for the purpose of developing vector anti-brucellosis vaccine. The obtained recombinant strain is a genetically stable construction. This stability is confirmed by the comparative analysis of the nucleotide sequences of the HA, NA, and NS genes of the recombinant vector virus Flu-NS1-124-Omp16 (H5N1) expressing the Omp16 gene of the Brucella abortus (GenBank: AAA59360.1). The comparative analysis showed that the nucleotide sequence of the NS gene of the first and the fifth passage level of the Flu-NS1-124-Omp16 (H5N1) virus corresponded for 100% to the initial part of 12AAS2TC_124 Omp16g containing the chimera NS1-124-Omp16 in the composition of DNA (deoxyribonucleic acid) plasmids pHW2000. Total identity with HA and NA genes of the strain A/AstanaRG/6:2/2009 (H5N1) was shown by the comparative analysis of the nucleotide sequences of HA and NA genes of the first and the fifth passage level of the recombinant strain Flu-NS1-124-Omp16 (H5N1). The recombinant vector virus Flu-NS1-124-Omp16 (H5N1) expressing the brucella Omp16 gene maintains the genetic stability during 5 passages in 10-day developing chicken embryos.