A New Strategy for the Detection of Chicken Infectious Anemia Virus Contamination in Attenuated Live Vaccine by Droplet Digital PCR
Figure 6
dd-PCR with vaccines contaminated with CIAV. (a) Results of droplet amplification with different concentrations of contaminating CIAV. The unbroken pink line is the threshold, above which are positive droplets (blue) with PCR amplification and below which are negative droplets (gray) without any amplification. (b) Positive and total droplets in the samples with different amount of contaminating CIAV. Low light blue is the number of positive droplets. High dark green is the number of total droplets. (c) Linear regression of the ddPCR assay for the copy number in vaccine contaminated with different dose of CIAV. The vertical axis shows the log 10 -transformed copy number/μL of the ddPCR reaction mixture. The horizontal axis indicates tenfold serial dilution series of the CIAV-contamination (100, 10, 1, and 0.1 EID50) of the ddPCR reaction. The inner error bars indicate the Poisson 95% confidence interval (CI) and the outer error bars show the total 95% CI of replicates. (d) The standard curve of the ddPCR with different concentrations. The estimated Pearson correlation coefficient of the CIAV copy regression curve (y = 94.293x—24.169) is 1 (R2 = 1, P< 0.001).