COVID-19 is caused by coronavirus SARS-CoV-2. Current systemic vaccines generally provide limited protection against viral replication and shedding within the airway. Recombinant VSV (rVSV) is an effective vector which inducing potent and comprehensive immunities. Currently, there are two clinical trials investigating COVID-19 vaccines based on VSV vectors. These vaccines were developed with spike protein of WA1 which administrated intramuscularly. Although intranasal route is ideal for activating mucosal immunity with VSV vector, safety is of concern. Thus, a highly attenuated rVSV with three amino acids mutations in matrix protein (VSV_MT) was developed to construct safe mucosal vaccines against multiple SARS-CoV-2 variants of concern. It demonstrated that spike protein mutant lacking 21 amino acids in its cytoplasmic domain could rescue rVSV efficiently. VSV_MT indicated improved safeness compared with wild-type VSV as the vector encoding SARS-CoV-2 spike protein. With a single-dosed intranasal inoculation of rVSV_ΔGMT-S_Δ21, potent SARS-CoV-2 specific neutralization antibodies could be stimulated in animals, particularly in term of mucosal and cellular immunity. Strikingly, the chimeric VSV encoding S_Δ21 of Delta-variant can induce more potent immune responses compared with those encoding S_Δ21 of Omicron- or WA1-strain. VSV_MT is a promising platform to develop a mucosal vaccine for countering COVID-19.

OBJECTIVE To comprehensively evaluate the quality of Sanzi powder from different batches based on 12 components quantitative analysis combined with chemical pattern recognition and entropy weight-TOPSIS method. METHODS The contents of 12 components in 15 batches of Sanzi powder （No. S1-S15） were determined by HPLC-MS/MS， such as ethyl gallate， gallic acid， ferulic acid， corilagin， genipin-1-O-β-D-gentiobioside， toosendanin， geniposide， caffeic acid， methyl deacetylated coumarinate， tannic acid， rutin， quercetin. Cluster analysis （CA）， principal component analysis （PCA）， and orthogonal partial least squares-discriminant analysis （OPLS-DA） were conducted on the assay results. Using variable importance projection （VIP） value＞1 and P＜0.05 as the evaluation criteria， the quality differential markers in Sanzi powder were screened. The entropy weight method was used to calculate the weight value， and TOPSIS method was used to rank the quality of 15 batches of Sanzi powder from superior to inferior. RESULTS The contents of the 12 components were 13.494-24.292， 2 069.608-3 188.100， 1.410-3.616， 1 065.030-2 630.584， 1 404.704-1 838.078， 101.640-354.268， 9 193.720-14 777.854， 1.240-5.060， 148.028-5 541.990， 4 261.422-5 607.438， 107.560- 195.512， 2.226-4.192 μg/g， respectively. The results of CA， PCA and OPLS-DA indicated that 15 batches of Sanzi powder could be clustered into two groups. Specifically， batches S3， S7， S10 and S15 were grouped into one category， and remaining batches were grouped into one category. VIP values of geniposide， quercetin， caffeic acid， and methyl deacetylated coumarinate were all greater than 1， with corresponding P-values less than 0.05. The results of the entropy weight-TOPSIS analysis revealed that methyl deacetylate exhibited the smallest information entropy and the highest weight. The relative closeness degrees of samples S3， S7， S10 and S15 ranged from 0.789 to 0.973， while the remaining samples ranged from 0.054 to 0.172. CONCLUSIONS The contents of 12 components in Sanzi powder could be determined accurately by using HPLC-MS/MS technology. Methyl deacetylated coumarinate， geniposide， quercetin and caffeic acid were identified as the quality differential markers. It was found that the overall quality of samples S3， S7， S10 and S15 were superior to that of other batches. Notably， the quality of Gardeniae Fructus decoction pieces emerges as a critical factor in ensuring the consistency of the preparation’s quality.