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Polyvinyl alcohol sponge implants were used in rats, mice, and guinea pigs to determine dose responses of growth factors. Eight differently treated sponges per rat or guinea pig (4/mouse) were injected with test material on alternate days and evaluated at day 8. Much of the observed response occurred in and around the capsule and was manifest as densely cellular granulation tissue. Including this capsular response in a single histologic slide ranking system provided a more sensitive and faster method of assessing growth factor effects than measurement of connective tissue ingrowth alone. Clear dose responsive effects were seen with recombinant human PDGF-BB, PDGF-AA, bFGF, and IL-1β, while EGF gave a lesser response. Lipopolysaccharide did not affect the connective tissue response, alone or in combination with PDGF-BB. PDGF-BB was tested in each species, and the dose response characteristics were qualitatively and quantitatively similar across species.

Twenty-six trichothecene mycotoxins produced by Fusarium sporotrichioides (MC-72083) and Fusarium sambucinum were screened for relative cytotoxicity in cultured baby hamster kidney (BHK-21) cells. The relative cytotoxicity was measured as LC100. The most cytotoxic trichothecenes were T-2 toxin (5 ng/ml) and the recently isolated 4-propanoyl HT-2 (5 ng/ml) and 3'-hydroxy T-2 toxin (5 ng/ml). T-2 tetraol (1 × 104 ng/ml), 8-ß-hydroxytrichothecene (1 × 104 ng/ml), sporotrichiol (2 × 104 ng/ml), 8-oxodiacetoxyscirpenol (6 × 104 ng/ml) and 8-acetyl T-2 tetraol (1 × 105 ng/ml) were the least toxic of the regular trichothecenes. None of the modified trichothecenes or the apotrichothecene were very cytotoxic: 8-ß-hydroxysambucoin (2 × 103 ng/ml), FS-1 (5 × 103 ng/ml), 8-a-hydroxysambucoin (8 × 104 ng/ml) and trichotriol (1 × 105 ng/ml). The modified trichothecenes, FS-2 and FS-3, were not toxic even at 1 × 105 ng/ml. The baby hamster kidney cell bioassay proved to be a very sensitive and reproducible means of screening new trichothecene mycotoxins for relative cytotoxicity.