Use of Paramecia for Studying Toxic Substances in Urine

Abstract

Dick and Henry 1 isolated hemolytic streptococci from the urine of scarlet fever patients in 1914. Later they 2 demonstrated that filtrates of scarlet fever streptococci contained a toxin which produced a reaction in the skin of persons who had not had scarlet fever. Since then Trask and Blake 3 showed that a toxic substance was present in the urine of scarlet fever patients from the 3rd to 6th day of the disease and that this toxic substance was neutralized by blanching human serum and by Dochez' s scarlatinal antistreptococcus horse serum. Recently 4 I have found paramecia useful for studying toxins from scarlet fever streptococci and found that these so called toxins could be neutralized by scarlet fever antitoxin from horses immunized with scarlet fever streptococci by a modification of the Dochez method (Laboratory of the Massachusetts Department of Health). Toxins from hemolytic streptococci from erysipelas, septicemia and pyemia were not neutralized by the scarlet fever antitoxin. I thought it would be interesting to see if paramecia could be used for studying toxic substances in urine, since it is not always convenient to get human beings for such experiments. Urine was filtered through filter paper and experiments were made as described in my previous article. Paramecia were grown in hay infusion broth. As with the filtrates of streptococci, diluted urine had no effect on paramecia. Normal horse serum, diphtheria antitoxin and scarlet fever antitoxin were diluted with hay infusion broth from 1: 100 to 1: 1600 and 1 part of each dilution was added to 5 parts of urine. One specimen contained 1 part of hay infusion broth and 5 parts of urine. These mixtures were incubated for one hour at 36 C, and then equal parts of each were added to the Paramecium culture in hollow