The Action of Bacterial Culture Products on Phagocytosis

[摘要] To sum up the experimental section: First, the action of culture broths of thirteen widely differing pathogenic and saprophytic bacterial species was tested on phagocytes in vitro . In every case the phagocytic power of the leucocytes was inhibited in a high degree. Second, tests, chiefly with a standard diphtheria toxin, were done to determine some facts concerning the nature of this substance depressing to phagocytic activity and its relation to the true toxins. These tests showed that its action was immediate, and could not be neutralized by the ordinary antiserums tested, nor destroyed by exposure to the degrees of heat or light used in the experiments. Variations in the constitution of the culture broths, which greatly affected true toxin production caused no variation in the production of the depressing substance. The depressing action of young culture broths was found to be less marked than that of older cultures. It was also found that digestion with proteolytic enzymes either wholly or partially destroyed the depressing element. The substance could be isolated by adsorbing it to leucocytes and then washing it from them with salt solution. After removal of the substance the leucocytes regained their phagocytic activity.

[学科分类] 生物科学（综合）