Optimal dose of enterococcal preparation (FK-23) supplemented perorally for stimulation of leukocyte reconstitution in dogs treated with cyclophosphamide.

Optimal doses of orally supplemented heat-killed Enterococcus faecalis FK-23 preparation (FK-23) were evaluated in dogs treated with cyclophosphamide (CY). Leukocyte reconstitution was stimulated by the supplement of 100 mg/kg of FK-23 through an induction of neutrophilia, and the treatment of 10 mg/kg of FK-23 induced mild neutrophilia in dogs tested. However, the reconstitution was not stimulated by the treatment of 200 or 400 mg/kg of the drug. Although the effects of FK-23 appeared to be milder than those of recombinant human granulocyte colony stimulating factor (rhG-CSF), there was no significant difference in the leukocyte reconstitution between the two substances. An appropriate dose of FK-23 is 100 mg/kg for augmentation of leukocyte reconstituting capacity in dogs treated with CY.