THE REACTIONS BETWEEN BACTERIA AND ANIMAL TISSUES UNDER CONDITIONS OF ARTIFICIAL CULTIVATION : II. BACTERICIDAL ACTION IN TISSUE CULTURES.

The results here reported confirm those of the former papers and strengthen the conclusions drawn therefrom. They may be summarized as follows: Chicken plasma has a marked bactericidal action on Bacillus typhosus, which may be in some slight degree overcome by the presence of growing tissue, especially splenic tissue, in the cultures. On Bacillus dysenterioe this bactericidal action of chicken plasma is present, but much less marked, and the same counteracting action of tissue, especially splenic tissue, is evident. On Bacillus coli verus chicken plasma has little or no bactericidal action. On Bacterium diphtheriticum chicken plasma has a very strong bactericidal action which may be strongly counteracted by the presence of growing tissue in the cultures. In all cases the bactericidal action of the plasma is decidedly diminished by dilution, as shown by the comparative results of these and the cultures formerly reported. The migrating white cells from splenic cultures, or substances closely associated with these cells, have a distinctly bactericidal influence on all organisms tested except Bacillus coli verus. Murphy states that lymphocytes first appear in the general circulation of the chick embryo on the 18th to 20th day, but in my cultures of splenic tissue cells resembling lymphocytes in morphology and behavior begin to appear in cultures of 11 or 12 day spleen and are abundant in cultures of spleen from 14 day or older embryos.