Bio-Rad Helios® Gene Gun System - Manual (Page 6)

Fig. 1. Location of the instrument serial number label on the Helios Gene Gun.
1.4 Ear and Eye Protection
Caution: Expansion of gas from high pressure to low pressure produces a sound
wave, the intensity of which is a function of the gas pressure. The intensity of the sound gen-
erated by discharging the Helios Gene Gun is ~108 decibels (db) at 400 psi; sustained noise
levels of 85 db or brief noise levels of 110 db may lead to permanent hearing damage. Hearing
protection should be worn by all those in the immediate vicinity when discharging the Helios
Gene Gun. Earmuffs or ear plugs provide equivalent protection against hearing damage.
Refer to Section 2.4 for suggestions on ear protection. Eye protection should always be
worn when working with high pressure gases.
Section 2
Introduction to Particle Delivery
2.1 Particle Delivery Technology
Particle bombardment is a physical method of cell transformation in which high density,
sub-cellular sized particles are accelerated to high velocity to carry DNA into cells. The tech-
nique was first described as a method of gene transfer into plants (Klein et al., 1987, 1988;
McCabe et al., 1988) and subsequently shown to be applicable to mammalian experimental
systems (Zelenin et al., 1989; Yang et al., 1990; Williams et al., 1991). Because it does not
depend on specific ligand-receptors and/or the biochemical features of structural components
typically present on cell surfaces, particle-mediated gene transfer can be readily applied to a
variety of biological systems. Consequently, this procedure can be used to transform such
diverse targets as bacteria (Shark et al., 1991; Smith et al., 1992), fungi (Armaleo et al., 1990),
and intracellular organelles (Johnston et al., 1988; Boynton et al., 1988). Since it is a physi-
cal method of gene delivery, particle bombardment also overcomes physical barriers to
effective gene transfer, such as the stratum corneum of the epidermis and the cell wall of
plants. Particle bombardment is a convenient method for transforming intact cells in culture
since minimal pre- or post-bombardment manipulation is necessary. In addition, this tech-
nique is much easier and faster to perform than the tedious task of microinjection. Both
transient and stable expression are possible with particle bombardment. In addition to DNA,
RNA may also be transferred to cells by particle bombardment (Qiu, et al., 1996). Table 1 lists
some of the advantages of using particle bombardment for in vitro and in vivo transformation.
2