Rudolph Hecht

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.

The absorption of whole ragweed pollen from the gastrointestinal tract

Abstract 1.1. The absorption of pollen allergen from the gastrointestinal tract was studied by means of the reactions produced in passively sensitized skin sites. 2.2. The appearance of the reaction varied, some giving reactions and some not. The results suggest that there is a relationship between the acidity present in the stomach at the time of ingestion of the pollen, and the absorption of the pollen allergen. 3.3. Artificial elevation or reduction of gastric acidity by oral administration of acids or alkalies tends to decrease, or, respectively, increase the absorption of orally administered pollen allergen.

Studies on the immunology of ragweed pollen proteins: II. Anaphylactic experiments

1. 1. Short ragweed pollen extracts as usually prepared contain two main types of molecular aggregates roughly classified as large and small. 2. 2. These may be separated by means of heat at the isoelectric point. 3. 3. The small molecular aggregate has a capacity to elicit skin reactions in patients sensitive to ragweed pollen. The large molecular aggregate as prepared in the present study has this capacity but to a less marked degree. 4. 4. The small molecular aggregate does not give precipitin reactions with ragweed precipitin antiserum. The large molecular aggregate gives positive precipitin tests with such antiserum. 5. 5. The small molecular aggregate is incapable of eliciting anaphylactic shock in guinea pigs sensitized to whole ragweed pollen. The large molecular aggregate is capable of eliciting anaphylactic shock in guinea pigs so sensitized.Abstract 1.1. Short ragweed pollen extracts as usually prepared contain two main types of molecular aggregates roughly classified as large and small. 2.2. These may be separated by means of heat at the isoelectric point. 3.3. The small molecular aggregate has a capacity to elicit skin reactions in patients sensitive to ragweed pollen. The large molecular aggregate as prepared in the present study has this capacity but to a less marked degree. 4.4. The small molecular aggregate does not give precipitin reactions with ragweed precipitin antiserum. The large molecular aggregate gives positive precipitin tests with such antiserum. 5.5. The small molecular aggregate is incapable of eliciting anaphylactic shock in guinea pigs sensitized to whole ragweed pollen. The large molecular aggregate is capable of eliciting anaphylactic shock in guinea pigs so sensitized.

Studies in Renal Denervation (IV)

I. Distribution of Intra-arterially Injected Oleokoniol. Rabbits were anesthetized with ether, a lumbar incision made, the viscera pushed to one side, and the aorta isolated and elevated proximal to the renal arteries. The aorta distal to the renal arteries was also isolated and a ligature applied. A hypodermic needle was inserted in the proximal portion of the aorta and Oleokoniol was slowly injected. The needle was left in place several minutes thereafter to allow for the distribution of the material, and then the proximal portion of the aorta was clamped and the animal killed. The kidneys were removed, sectioned, and stained with Sudan III and hematoxylin. Microscopic examination revealed that the oil was distributed equally on both sides. This procedure was repeated on animals denervated according to the technique of Milles, Müller and Petersen. 1 The left kidney was denervated and the right kidney kept intact for control. The animals were allowed to recover for 2 to 3 weeks before injections were undertaken. Microscopic examination revealed that the denervated kidneys contained more oil than normal kidneys. This agrees with the findings of Milles, Müller and Petersen, 2 who described the dilatation of the vascular bed in denervated kidneys. II. Bacterial Embolism in the Normal and Denervated Kidney. After having experimented with bacterial suspensions in denervated kidneys, 3 and having determined that the control kidney contained more emboli than the denervated kidney, the effect of chilling and of injection of epinephrine, followed by the intravenous injection of an attenuated Staphylococcus suspension was tried. Rabbits in whom the left kidney had been denervated were used. A 2-week as well as a 2-month recovery period was allowed. The animals were chilled in a bucket of crushed ice and water, until a severe chill had developed.

Studies in Renal Denervation.20 III. Bacterial Embolism in the Normal and Denervated Kidney

Medium sized rabbits were used throughout the experiment. The left kidney was denervated and the right kidney was left intact and used as a control. The rabbits were placed on normal diet. The kidney was approached through a lumbar incision and denervated according to the method described by Milles, Muller and Petersen, 1 except that the animals were placed under ether anesthesia instead of Nembutal. Some of the animals were allowed to recover for 2 weeks; others for 2 months. Five cc. of a concentrated suspension of an attenuated culture of Staphylococcus aureus in physiological salt solution was injected into the marginal ear vein of each rabbit. The fine clumps of bacterial growth were not broken up when removed from the agar plates and placed into the salt solution, in the hope that embolus formation would thus be favored. This was first tried on unoperated animals to determine the dosage necessary to produce emboli. It had been previously determined that this dosage would kill such rabbits in 4 to 5 days. It was then tried on denervated rabbits and the results indicated that the denervated kidneys contained about half as many emboli as the intact kidney. The following rabbits were then used to make exact counts of the number of micotic abscesses formed. They were killed on the morning of the fourth day after the bacterial injection by injecting ether into the heart, the kidneys removed and fixed in formalin. Corresponding parts of the kidneys were sectioned serially and examined microscopically. The emboli were counted and the following results were obtained:

The vial syringe technic for intracutaneous tests

Summary A vial syringe technic is described for intracutaneous tests which eliminates the separate use of containers and tuberculin syringes. The advantages which it offers are: 1. Compactness, rendering transportation easy for hospital use; 2. Time saving, since it eliminates the repeated washings of tuberculin syringes; 3. Economy, in the avoidance of tuberculin syringes and in the more efficient use of testing materials.