The invention features incapacitated whole cell bacterial immunogenic compositions
produced by infecting a bacterium with Lys minus bacteriophage, which are deficient
in the lysin protein. Lys minus bacteriophage retain activity in infection of its
appropriate bacterial host, destruction of the bacterial genome, and replication,
which are sufficient to inhibit bacterial growth and replication. The resulting,
Lys minus-infected bacterium is provided in a state of bacteriostasis, and is not
capable of replicating further (e.g., is "incapacitated"). The incapacitated bacterium
can then be used as to elicit an immune response for prophylactic and/or therapeutic
purposes. The invention thus also features incapacitated bacteria formulated appropriately
for use in immunogenic compositions for eliciting an immune response, e.g., for
production of antibodies in a non-human host or in a whole cell bacterial vaccine.
