Six gene segments, PB1, PB2,PA, NP, M and NS, were fully synthesized which derived from the master donor virus(MDV), cold-adapted(ca),temperature sensitive(ts), live attenuated influenza virus strain A/Ann Arbor/6/60(MDV-A). Meanwhile, five amino acid substitutions (PB1-391E, 581G, 661T, PB2-265S, NP-34G) were artificially altered by human intervention. HA and NA fragments derived from the 2006～2007 circulating strain A/New Caledonia/20/99 (H1N1). Eight fragments were ligated with modified pAD3000 for rescue plasmid construction. Eight transcription/expression plasmids were named as pMDV-A-PB2, pMDV-A-PB1, pMDV-A-PA, pMDV-A-NP, pMDV-A-M, pMDV-A-NS, pMDV-A-HA, pMDV-A-NA, respectively. The COS-1 cells were co-transfected with eight plasmids representing 6 internal viral backbone of the strain A/AA/6/60 and two plasmids containing the cDNA of the HA and NA segments of the strain A/New Caledonia/20/99 (H1N1), the results showed that cold-adapted, attenuated reassortant influenza A virus was rescued successfully. Titers of a reassorted influenza A virus in embryonated chicken eggs ranged from 1∶29 to 1∶210. The rescue system of six internal genes used as backbone opens the way for further research on gene function and neotype vaccine candidate of cold-adapted, live attenuated human influenza virus.

Six gene segments,PB1,PB2,PA,NP,M and NS,were fully synthesized which derived from the master donor virus (MDV),cold-adapted(ca),temperature sensitive(ts),live attenuated influenza virus strain A/Ann Arbor/6/60(MDV-A).Meanwhile,five amino acid substitutions (PB1-391E,58lG,661T,PB2-265S,NP-34G) were artificially altered by human intervention.HA and NA fragments derived from the 2006-2007 circulating strain A/New Caledonia/20/99 (H1N1).Eight fragments were ligated with modified pAD3000 for rescue plasmid construction.Eiight transcription/expression plasmids were named as pMDV-A-PB2,pMDV-A-PB1,pMDV-A-PA,pMDV-A-NP,pMDV-A-M,pMDV-A-NS,pMDV-A-HA,pMDV-A-NA,respectively.The COS-l cells were co-transfected with eight plasmids representing 6 internal viral backbone of the strain A/AA/6/60 and two plasmids containing the CDNA of the HA and NA segments of the strain A/New Caledonia/20/99 (H1N1),the results showed that cold-adapted,attenuated reassortant influenza A virus Was rescued successfully.Titers of a reassorted influenza A virus in embryonated chicken eggs mnged from 1:29to l:210.The rescue system of six intemal genes used as backbone opens the way for further research on gene function and neotype vaccine candidate of cold-adapted,live attenuated human influenza virus.

Although the development of COVID-19 vaccines has been a remarkable success, the heterogeneous individual antibody generation and decline over time are unknown and still hard to predict. In this study, blood samples were collected from 163 participants who next received two doses of an inactivated COVID-19 vaccine (CoronaVac®) at a 28-day interval. Using TMT-based proteomics, we identified 1,715 serum and 7,342 peripheral blood mononuclear cells (PBMCs) proteins. We proposed two sets of potential biomarkers (seven from serum, five from PBMCs) at baseline using machine learning, and predicted the individual seropositivity 57 days after vaccination (AUC = 0.87). Based on the four PBMC's potential biomarkers, we predicted the antibody persistence until 180 days after vaccination (AUC = 0.79). Our data highlighted characteristic hematological host responses, including altered lymphocyte migration regulation, neutrophil degranulation, and humoral immune response. This study proposed potential blood-derived protein biomarkers before vaccination for predicting heterogeneous antibody generation and decline after COVID-19 vaccination, shedding light on immunization mechanisms and individual booster shot planning.
Humans ; COVID-19 Vaccines ; Leukocytes, Mononuclear ; Proteomics ; COVID-19/prevention & control* ; Vaccination ; Antibodies ; Antibodies, Viral ; Antibodies, Neutralizing