Stimulating Effect of Tuberculin upon Production of Circulating Antibodies in Guinea Pigs Infected with Tubercle Bacilli

Summary

Guinea pigs infected with small amounts of tubercle bacilli and not subsequently skin tested did not produce, in detectable amount, antibodies which agglutinated sheep erythrocytes sensitized with old tuberculin.

When guinea pigs, previously infected with BCG, were injected with small amounts of old tuberculin, agglutinating antibodies appeared in the blood within 4 to 5 days.

Antibodies agglutinating erythrocytes sensitized with old tuberculin appeared also when BCG infected animals were injected with ovalbumin.

This stimulation by old tuberculin of the production of agglutinating antibodies did not seem to be correlated with the existing degree of skin hypersensitivity to tuberculin. However, the stimulating effect became apparent only after hypersensitivity was established.

The simultaneous injection of old tuberculin and ovalbumin into guinea pigs, either normal or infected with BCG, resulted in considerably higher titres of antibodies to ovalbumin than were produced by the injection of ovalbumin alone.

In order to avoid confusion of substances of bacterial origin which sensitise erythrocytes to agglutination by specific antibacterial serum with bacterial hemagglutinins, which themselves cause agglutination of erythrocytes, the term “bacterial hemosensitins” is proposed for the former.