Fig. 6.

Low level SIV RNA signal detection on the Raindance platform using the SIV RT-ddPCR assay. (A) A negative control sample which contains 1 μg background RNA extracted from the peripheral blood mononuclear cells (PBMC) from a naïve (i.e. uninfected) animal. (B-E) each corresponds to an average of 5 copies of SIV RNA standard spiked in 1 μg background RNA extracted from the PBMC from the same naïve animal as in (A). “SIV+” indicates SIV positive droplets. (F) Quantitation and statistics data corresponding to (A-E). The normalized SIV + values were calculated as described in [20]. The average SIV + value for (B-E) was 6, and the coefficient of variation (CV) was 26.1%. Note that at the 5-copy target input level, the exact copies of the target templates that are present in the reactions follow a Poisson distribution, due to the stochastic limitations inherent in target sequence distribution in the volume of sample aliquots taken for testing.