Fig. 2: Replication capacity of H3N2 LAIV prototypes with different proportions of DIPs and induced innate immune responses. | Nature Communications

Fig. 2: Replication capacity of H3N2 LAIV prototypes with different proportions of DIPs and induced innate immune responses.

From: Live attenuated influenza vaccine with low proportions of defective interfering particles elicits robust immunogenicity and cross-protection

Fig. 2: Replication capacity of H3N2 LAIV prototypes with different proportions of DIPs and induced innate immune responses.

a Schematic diagram of H3N2 LAIVs containing different proportions of DIPs. b Replication capacity of H3N2 LAIVs with low DIPs (MOI = 1), high DIPs (same STV, MOI = 1), or high DIPs (same Total, MOI = 0.015) in MDCK cells (n = 4 biologically independent samples). The total intracellular NP RNAs were detected via reverse transcription quantitative PCR (RT-qPCR) using NP primers located in the packaging signal region (left). The progeny infectious virus titers in the supernatants were detected using FFA (middle). The progeny total virus particle titers in the supernatants were detected using HAU (right). c, d Female 6–8-week-old BALB/c mice were intranasally inoculated with 30 µL of low DIPs LAIV (5.25 × 106 EID50/mouse, 1.46 × 107 total particles/mouse), high DIPs LAIV (same STV, 5.25 × 106 EID50/mouse, 1.05 × 109 total particles/mouse), or placebo (n = 6). c Replication capacity of H3N2 LAIVs with different DIP proportions in mouse turbinate and lung tissues (n = 3 biologically independent mice). d Body weights of the mice within 13 dpi (n = 3 biologically independent mice). e Expression of RIG-I in A549 cells infected with LAIVs with low DIPs (MOI = 0.1), high DIPs (same STV, MOI = 0.1), or placebo at 8 hpi. MW: molecular weight. Two independent experiments have been replicated, each with two biologically independent samples. f Expression of IFN-α and IFN-β mRNA in A549 and DC2.4 cells infected with LAIVs with low DIPs (MOI = 0.1), high DIPs (same STV, MOI = 0.1), or high DIPs (same Total, MOI = 0.0015) at the indicated time points (n = 3 biologically independent samples). All data are presented as the means ± SD. Statistical significance was calculated by two-sided Student’s t test (b–d, f-left) or one-way ANOVA with Tukey’s multiple comparison tests (f-right). a created in BioRender. Su, W. (2025) https://BioRender.com/k69zm81. Source data are provided as a Source Data file.

Back to article page