Since the introduction of methods of application of the tuberculin test, the results of which are determined by means of the local inflammatory reaction occurring at the site of application, much discussion has arisen with regard to the best mode of procedure and the practical value of the results obtained.
That the tuberculin reaction represents a phenomenon of sensitization is now generally conceded, and, in order to understand fully its significance, it may be well to consider briefly the mechanism involved in the production of sensitization. Normally, foreign proteins as such do not gain entrance into the body. The most frequent pathologic state in which complex proteins do enter the body as such is represented by the bacterial infections in which the bacterial cells represent highly specialized
VAUGHAN VC. IMPORTANCE OF THE TUBERCULIN REACTION IN THE DIAGNOSIS OF EARLY PULMONARY TUBERCULOSIS. JAMA. 1913;61(18):1591-1597. doi:10.1001/jama.1913.04350190009003