Preparation of Diphtheria Toxin Solution Requiring no Control in the Schick Test

[摘要] The results of the lethal and intradermal tests in guinea pigs clearly show that the proposed diluent, consisting of a peptic digest of human serum proteins, acts as an effective stabilizer of the very dilute solution of diphtherial toxin used in the Schick test. After being held at 2 C. for 27 months no loss in activity was detected.[12][1] The new solution possesses, therefore, good preserving power, an indispensable requirement of any proposed diluent for this toxin.Of the 24 subjects who were seen 24 hours after the injections and daily thereafter only two showed some reaction at the site of the new control, in both instances this lasted only one day and was negligibly small. Of the 28 individuals who were not seen for the first time until 72 hours after the injections there were three who showed some reaction at the site of the new control; in one instance the erythema persisted to the eleventh day, in the other two it disappeared between the 7th and 10th days. In all three it was so small (2 × 2 or 2 × 3 mm) at all times as to make it appear that it was due to trauma, at least in part. In no instance would the omission of the control injection have resulted in a different Schick reading. The removal of “bacillary protein”, the large reduction in broth “nitrogen” and the use of the new diluent seem therefore to have accomplished the purpose of eliminating the need for a control injection in performing the Schick test.It would seem, that the best time for making a reading is the fourth or fifth day after the injection. In every instance but one among the persons read as Schick-positive with the new toxin the erythema measured greater than 20 mm in one direction at its height; in this one case the dimensions were 12 × 6 mm. [1]: #fn-2

[学科分类] 生物科学（综合）