Bio-Rad Helios® Gene Gun System - Manual (Page 39)

Table 4. Suggested starting conditions for in vitro transformation
of tissue culture cells using the Helios Gene Gun.
Parameter Conditions
Helium pressure: 50–200 psi
PVP: 0–0.015 mg/ml
MLQ: 0.125–0.5 mg/tube
Microcarriers: 1.0 or 1.6 µ gold
DLR: 0.5–2.5 µg DNA/mg gold (0.06–1.25 µg DNA/cartridge)
7.3 Parameters for in vivo Delivery
The following are suggested starting conditions for optimizing DNA delivery to the skin of
various species. Each laboratory should determine the optimum parameters for their particular
application (see Section 7.1 and Table 5). Bombardment conditions are those used in references
cited in Section 10.8 using the Accell Gene Gun. Use this information as a starting point when
optimizing bombardment conditions with the Helios Gene Gun. Lower helium pressures should
be tested early in the optimization process.
Table 5. Examples of parameters for delivery into skin of various
species
Species Site MLQ(mg/target) DLR(µg/mg) PVP(mg/ml) psi
Dog 9 Dorsum 0.5 1–2 0.1 300
Monkey 7, 8, 9 Abdomen 0.25 2 0–0.05 300–400
Mouse 17, 19 Abdomen* 0.25–0.5 1–2.5 0–0.1 300–500
Pig 7, 8, 10 Inner thigh 0.25–0.5 0.5–2.5 0.05 500
(clipping not
necessary)
Rabbit 27 Back 0.5 1–2 None 350–400
* Do not use a depilatory agent to remove the fur (Section 6.3, step 3)
Section 8
Troubleshooting
8.1 DNA/Microcarrier Preparation
Problem Microcarriers agglomerate after coating with DNA.
Possible solutions Lower DNA Loading Rate.
8.2 Cartridge Preparation
Problem Gold does not spread evenly in the Gold-Coat tubing (rings,
clumps, uncoated sections, streaks).
Possible solutions Eliminate any potential sources of water in the tube and in the
final DNA/Microcarrier preparation.
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