The present invention is directed to an in vitro method for producing T lymphocytes. For example, the air circulating device includes a number of spokes or fan blades secured between the outer peripheral portion and the hub portion of the brake disc, and inclined relative to the brake disc. The amplifier circuit is supplied with electrical energy by the energy supply device. The method ensures that a suitable aerosol can has been properly loaded in the dispenser. In one embodiment, at least three encryption keys are used such that the encryption attribute is encrypted with using a third key.