Local Hypersensitiveness

With the blood serum of tuberculous guinea pigs, hypersensitive to eggwhite, it was possible to transfer the hypersensitiveness passively. In the passively sensitized guinea pigs, both tuberculous and non-tuberculous, only the large evanescent type of reaction was observed. A sensitiveness toward tubercle bacillus extract, similar in type to the reactions of guinea pigs passively sensitized toward eggwhite, could be transferred with the sera of tuberculous guinea pigs treated with tubercle bacillus extracts. The passive sensitiveness increased in strength during several days following the serum injections.

Local Hypersensitiveness

As we stated at the beginning of this paper our observations add to the observations of Lewis and Loomis concerning the increased antigenic response of the guinea pig during the tuberculous infection that beside the increased antibody production strong hypersensitiveness can develop and only small amounts of eggwhite are necessary for a strong response. It could not be decided whether the strong necrotic local reactions observed in the tuberculous animals are essentially similar to the evanescent reaction observed in the non-tuberculous animals or with the tuberculin reaction, and the connection between the sensitiveness and serum antibodies remained undecided. If a similar increase of the response, as it can be observed in the tuberculous animal, is present in the course, or in certain phases of the course, of other infectious diseases the importance of it for the development of immunity and the symptoms of the diseases is evident. We have only little information as to whether or not such influence in other cases is present.

Local Hypersensitiveness

Non-tuberculous guinea pigs after treatment with eggwhite react to the intracutaneous injection of varying amounts of egg-white with a quickly developing large swelling, which disappears in twenty-four to forty-eight hours. This reaction corresponds to the reaction called “immediate” by Zinsser.

In tuberculous guinea pigs after treatment with eggwhite there appears first a sensitiveness similar to that of the non-tuberculous guinea pigs, but usually in a few days it gives place to a persistent necrotic reaction. After a shorter or longer period the evanescent reaction may reappear.

The hypersensitiveness of tuberculous guinea pigs demonstrated with the necrotic skin reaction is similar to the Arthus phenomenon of rabbits. Subcutaneous injections cause very extensive necrosis, but do not kill the animal. Precipitins are present in large amount in the blood serum. Anaphylaxis against eggwhite is also present.

In general there seems to be a parallelism between the precipitin content of the blood serum and the sensitiveness. But in four tuberculous guinea pigs of the two first series which produced precipitins only slightly, two were very sensitive, and several with strong precipitin production were only slightly sensitive.

Sensitiveness and precipitins appear about the same time—around the seventh day after treatment. Very small amounts of eggwhite are needed for the production of both.

The complement fixation has no direct connection either with the sensitiveness or precipitation. In no case did we observe complement fixation with crystalline egg albumin.

Desensitization is possible with larger doses of eggwhite given subcutaneously. The tuberculin reaction is only slightly affected.

The sensitization with the eggwhite is mainly against the egg globulin. With egg globulin the sensitization is as successful as with the eggwhite. With egg albumin we obtained necrotic skin reaction only after more prolonged treatment.

After treatment with timothy pollen we obtained in two animals a strong necrotic skin reaction, and in two others a moderately strong reaction. The formation of precipitins and complement fixation antibodies were observed only in the tuberculous animals. With typhoid bacilli we obtained in the tuberculous animals neither sensitiveness nor increased agglutinin formation.

On the Antigenic Substances of the Tubercle Bacillus

It has been shown that beside the non-protein precipitable substance present in the tubercle bacillus extracts the protein substances of the extracts are potent antigens in the complement fixation test.

All three of the antigens demonstrated in the tubercle bacillus, the protein substances, the alcohol soluble specific substance, and the carbohydrate precipitable substance of Mueller and of Laidlow and Dudley, as they occur in our preparations, are distinct and separate antigens.

A short description is given of the properties of the known antigens of the tubercle bacillus and of the response of the animal organism to them. Some related questions are briefly discussed.

The Non-Specific Activation in the Complement Fixation Test of the Alcohol Soluble Antigens of the Tubercle Bacillus

It was found that the potency of certain preparations obtained from the alcohol extract of the tubercle bacillus as antigen in the complement fixation was increased 80 to 160 times by the addition of commercial lecithin. The potency of the original alcohol, ether, and watery extract was increased considerably less (2 to 10 times). Substances separated from the alcohol extract of the tubercle bacillus or cholesterin had no effect on the potency of the preparations. One millionth of a milligram of the specific substance (the dilution 1:400,000,000) in combination with lecithin was enough to cause as antigen a complete reaction in vitro. The significance and eventual consequences of these observations for the understanding of certain serological reactions are briefly discussed.

On the Specific Substances in the Alcohol Extract of the Bacillus of Tuberculosis

In a table are given the amounts extracted with the successive use of different lipoids solvents from 31 grams of tubercle bacilli and the effectiveness of the extracts as antigens in the complement fixation test.

With the separation of the ether and alcohol soluble and acetone insoluble fraction of the extracts and in several cases with washing them with water, we obtained from all extracts examined (5 ether, 1 ethyl and 1 methyl alcohol extract) preparations which were active as antigens very closely in the same amount, 0.00020 to 0.00030 mgm. being the antigen unit. We did not succeed with continued purification in enhancing more the potency of the preparation.

The chemical examination of the purified products, as far as could be made, has shown them to be closely similar to each other. Carbohydrates are present in large amounts in the non-purified alcohol extracts and from 12 to 26 per cent of them were found in the preparations obtained both from the alcohol and ether extracts in different phases of the purification process. The amount of carbohydrates in the most effective preparations and their eventual connection with the specific properties of the preparations has not yet been examined. The purified product has a chemical composition widely different from the well studied phosphatides.

The very high potency of the preparations, the close uniformity of the potency and chemical composition of the preparations obtained from different extracts, constitute a certain probability that our preparations consist in a large part of the specific substance.