William H. Welker

Studies on the Chemistry and Immunology of Ragweed Pollen Proteins

Summary The protein of ragweed pollen has been separated into fractions. The one fraction has relatively large molecular size and is responsible for the precipitin reaction with pollen antiserum. The other fraction is made up of proteins of relatively small molecular size and is the skin reactive protein of pollen. This last observation is similar to that of Benjamins and his collaborators, 1 who in their work on grass pollen, came to the conclusion that the skin reacting substance is of small molecular size. Our results differ from those obtained by Harley. 2 He concludes that in timothy pollen the skin reactive fraction consists of proteins of the albumin type. We failed to produce hyposensitization of ragweed sensitive patients by the use of the fraction containing small protein molecules. There is an indication that it may be possible to do so when it is used in connection with large protein molecules. Benjamins and his collaborators found that the skin reactivity of the small protein molecule from grass pollen could be enhanced by the addition of protein of large molecular size. The immunizing properties of the fraction consisting of the larger protein molecules are now being studied.

Precipitin Antisera for Malignant Tissue

Conclusions 1. Specific antisera have been prepared for the proteins of malignant tissue. 2. There is a suggestion of a relative anatomic specificity of carcinomatous tissue, as a greater number of positive reactions occur with autolysates of the homologous tissue and with sera of cases having the same type of malignancy. 3. These precipitins for the proteins of malignant tissue show promise as diagnostic aids. A high percentage of sera from patients with malignant tumors react positively. The higher percentages of positive reactions were obtained in cases where the malignant growth had the same anatomic location as the tumor from which the anti-serum had been prepared. 4. Our preliminary results indicate that possibly these precipitins are species-specific, because antisera for rat-tumors do not react with autolysates of human carcinoma and vice-versa.

Tulip bulb dermatitis

Abstract A case of tulip bulb dermatitis of the hands is described. The toxic reacting substance was present in the ether soluble fraction of the plant and absent from the albumin and globulin fractions.

Is Ferratin Precipitinogenic

In 1893 Schmiedeberg 1 announced that it was possible to extract a protein from the liver by means of boiling water. The extract was filtered and the filtrate treated with tartaric acid for precipitation of the protein. Schmiedeberg concluded that this was a high iron containing protein but not a nucleoprotein. He named it ferratin. Subsequent investigators, 2 however, came to the conclusion that the protein extracted in this fashion was really a nucleoprotein, or derived from nucleoprotein. Since by repeated extraction and precipitation it seemed probable that ferratin could be completely separated from the accompanying blood and lymph proteins, it seemed advisable to test its antigenic properties. Our first experiment was unsuccessful and new ferratin was prepared with particular care to avoid its exposure to any undue hydroxyl ion concentration. In dissolving the ferratin it was suspended in water and 0.5% sodium carbonate solution was added slowly with constant stirring in such quantities that the solution showed only the faintest reaction to litmus. No attempt was made to dissolve completely all the suspended material and the undissolved portion was removed by filtration. Numerous experiments were made to determine whether ferratin is precipitinogenic. As the rule 2, 4, 6, 8, 10 or 12 cc. of the 1% solution of ferratin were introduced intravenously in rabbits at intervals of 3 or 4 days and on the fourth day after the last injection the serum was tested for precipitin by the contact or layer method.