This two-step method used in the Clostridium difficile toxin transport is a unique method of delivery. The use of a vaccine (TAA/ecdCD40L) for the interdiction of this two-step delivery toxin system to reduce cell death and the death of human subjects is believed to be unique in the area of neutralizing antibodies for protection against the lethal effects of an infectious agent. The proposed composition/vaccine strategy for C difficile is to combine and administer at the same time the two compositions/vaccines for Toxin A, the one composition/vaccine for Toxin B and the one vaccine for CDTb to determine the effect of mixing these compositions/vaccines on protecting mice from a lethal dose of C difficile. This is believed to be the first time that two different tandem repeats from the contact of a ligand with its cellular receptor have been used to prevent binding of the ligand to its cellular receptor.
