“Procutins” and “Anticutins” *

During the early phase of bacteriological-immunological work on tuberculosis, many answers to unsolved questions were sought in serological reactions and in antigen-antibody relations, demonstrable either in vitro or in vivo. A product of that time is the work of Pickert and of Lowenstein3 on the so-called "procutins" and "anticutins." They were considered in terms of antibodies specific to tuberculin. These authors observed that in appropriate mixtures of Old Tuberculin and serum, the skin reactivity of tuberculin was either enhanced (procutins) or decreased (anticutins). These "cutins" were related to the immunological status of the serum donors. The theories built on such studies have long since gone the way of all immunological theories in tuberculosis, the main basis for which were humoral "antibodies." There would be no useful reason to revive work along these lines, were it not for the fact that, relatively recently, Martenstein4 found that the high frequency of anergy to tuberculin in sarcoidosis is apparently related to anticutins. He believed that patients with sarcoidosis did not react to tuberculin because they carried anticutin in their sera. In other words, humoral, tuberculin-neutralizing factors prevented the common manifestation of an actually existing allergy. This theory received further support by the observation of Jadassohn2 that (1 ) rats respond to the introduction of tubercle bacilli by the formation of lesions that greatly resemble histologically the sarcoid lesions in man, and (2) rat serum contains tuberculin-neutralizing factors (anticutins). In a previous publication, it was mentioned that anticutins had been demonstrated in three patients with sarcoidosis. It was well realized that the findings in three patients could not carry much weight, but more patients with sarcoidosis were not available at the time. Furthermore, it remained to be determined whether sera from normal persons and from tuberculous patients exerted any demonstrable effect upon the skin-reacting element in 0 T.