TABLE 2.
Effect of DNA background on the amplification of A. phagocytophilum
| Dilutiona | Threshold cycles (Ct) in various DNA backgroundsb
|
|||
|---|---|---|---|---|
| Water | Human | Tick | Mouse | |
| 10−3 | 19.2, 19.2, 19.6 | 18.8, 18.8, 18.8 | 18.3, 18.6, 18.9 | 18.8, 18.7, 18.9 |
| 10−4 | 22.1, 22.4, 22.5 | 22.1, 22.0, 21.9 | 21.4, 21.4, 21.7 | 21.7, 21.6, 21.7 |
| 10−5 | 26.9, 26.9, 27.2 | 25.8, 25.7, 25.3 | 25.1, 25.0, 26.1 | 25.0, 24.8, 24.7 |
| 10−6 | 30.1, 30.2, 30.5 | 29.4, 29.0, 29.1 | 29.3, 29.0, 29.4 | 28.6, 29.1, 28.5 |
| 10−7 | 34.1, 34.1, 33.5 | 33.8, 32.7, 33.3 | 32.8, 32.4, 33.1 | 34.0, 33.8, 32.8 |
a
Values represent the dilution factor using DNA extracted from A. phagocytophilum strain USG3 grown in HL-60 cells. The diluent for each dilution series consisted of undiluted DNA extracted from 200 μl of EDTA-treated whole blood (human), a single adult I. scapularis tick (tick), or 50 μl of EDTA-treated whole blood (mouse).
b
Each value represents the threshold cycle from one of three separate real-time multiplex PCR amplifications.