Soluble polyglycans enhance recovery from cobalt-60--induced hemopoietic injury.

Six soluble polyglycans (glucan-C, glucan-F, glucan-S, krestin, lentinan, and schizophyllan), two soluble polymannans (mannan-A and mannan-R), and one soluble polyfructan (levan) were assayed for their ability to enhance hemopoietic recovery in C3H/HeN mice when administered either 1 h before or 1 h after a 6.5-Gy dose of cobalt-60 radiation. Hemopoietic recovery was measured by the endogenous spleen colony assay and was compared with recovery in both radiation control mice and irradiated mice treated with glucan-P (a particulate polyglycan previously shown to enhance recovery from radiation-induced hemopoietic injury). Compared with radiation controls, when administered before irradiation, mannan-A, glucan-F, and glucan-S enhanced endogenous colony formation 4.2-5.1-fold (equivalent to glucan-P), and levan and schizophyllan approximately 2.7-fold. Lentinan, krestin, mannan-R, and glucan-C did not enhance hemopoietic recovery above radiation controls under these conditions. When polyglycan administration was delayed until after irradiation, endogenous colony formation was enhanced 3.0-3.9-fold by mannan-A, schizophyllan, glucan-S, krestin, and glucan-F (at least comparable with glucan-P) but not at all by mannan-R, levan, lentinan, or glucan-C.