Protective effect of SPR-901 (RBS) on the decrease of peripheral leukocyte number in 5-fluorouracil-treated mice

Effect of orally administered heat-killed Enterococcus Faecalis FK-23 preparation on neutropenia in dogs treated with cyclophosphamide

Dogs injected intravenously for 3 days with cyclophosphamide (CY) at a dose of 10 mg/kg were given 100 mg/kg of Enterococcus faecalis FK-23 preparation (FK-23) perorally for 14 days to confirm the beneficial effects of the latter drug in neutropenic dogs when orally administered. Although FK-23 treatment did not inhibit CY-induced neutropenia, it augmented neutrophil-reconstituting capacity in these dogs. Increases in the myeloid/ erythroid ratio and neutrophilic lineages were found in the bone marrow of FK-23 administered dogs. The oral administration significantly restored the reduced activity of neutrophil phagocytosis and chemiluminescence in dogs treated with CY. These findings indicate that FK-23 administered perorally not only augments neutrophil reconstitution through the activation of bone marrow but also functions in dogs treated with CY. It may thus be a useful supportive agent to reduce the adverse side-effects associated with the administration of chemotherapeutic agents such as CY.

Effect of antitumor polysaccharide SPR-901 on antitumor activity in combination with 5-FU

We have examined the effects of the antitumor polysaccharide SPR-901 in combination with 5-fluorouracil (5-FU) on the antitumor activities against mouse syngeneic tumors. SPR-901 was administered p.o. from day 1 to day 10 at the dose rate of 30 mg/kg, and 5-FU was injected i.p. from day 1 to day 5 at the dose rate of 20 mg/kg after BALB/c mice were injected s.c. with 6 x 10(4) cells/mouse of Meth A on day 0. Tumor sizes of mice treated with both SPR-901 and 5-FU were significantly smaller than those from the untreated control group on days 10, 15 and 20. LAK activity of spleen cells from mice treated with both SPR-901 and 5-FU was higher than that from the untreated control group and either the SPR-901 or 5-FU treated group. Flow cytometrical analysis revealed that spleen cells from mice treated with both SPR-901 and 5-FU were much more abundant in both T-cell receptor alpha/beta+ and IL-2 receptor alpha+ T-cells. Furthermore, spleen cells from both the SPR-901- and 5-FU-treated groups exhibited higher growth responses to IL-2 than that from the untreated control group and either of the SPR-901- or 5-FU-treated groups. Therefore, the effects of the antitumor polysaccharide SPR-901 used in combination with 5-FU were augmented as compared with single drug use.