[Sulphated glycosaminoglycans as virus inhibitors. 2nd communication: Inhibitory effect of glycosaminoglycanpolysulphates on yellow fever virus 17 D in animal experiments (author's transl)].

Glycosaminoglycanpolysulfates (GAGPS) have virus inhibiting properties demonstrable by means of tissue culture in the plaque method. In brain preparations of children who had died of a hyperpyretic toxicosis, cell necroses were found corresponding to the picture of tissue culture plaques. The question arose from these observations whether this inhibiting effect of GAGPS can perhaps also be demonstrated in vivo. In animal experiments, cell necroses corresponding to those of the infant brain could be observed during the course of a 17 D yellow fever encephalitis in mice. The Luitpoldt-Werk Munich placed to our disposal 13 different GAGPS for tests. Each of these substances was tested in 210 mice (fig. 1). Virus dilutions (LD 50/ml) were mixed to the same volume with the indicated concentrations of substance directly before vaccination. The differing LD 50 doses is due to the fact that each ampoule contains a different content of virus.) The toxicity of all substances is practically zero (table 2a, 2b). The effect of the inhibiting substances was evaluated at first by means of a deviation of the rate between alive and dead animals (table 1). The statistical significance of the effect of some substances was that high so that an inhibition of the virus replication has obviously to be considered. The significance for L1 and L4 - they are chemically very similar - is higher than 0.001 (table 4). The virus inhibiting effect of the substances was controlled by histopathology. 31 brains of mice were dissected and histologically evaluated; the lesions of the brains were examined and recorded (table 3). The effect of the substances was measured by absence or diminution of the lesions. The most effective substance was L1 as far as its concentration was higher than the critical limit of 625 gamma/ml.