A few years ago it occurred to certain French observers that the preliminary removal of the fatty portion of the tubercle bacillus might facilitate the production of a more potent antigen for use in the treatment of tuberculosis. In brief, this was accomplished by extracting the killed and dried tubercle bacilli with acetone. The acetone was then removed by filtration, and the defatted organisms were suspended in methyl alcohol for some days and then filtered. The filtrate thus obtained was designated methylated antigen, and after suitable dilution with physiologic solution of sodium chloride was injected into laboratory animals and later into man.
In 1925, Negré and Boquet1 reported the results they obtained with methylated antigen in tuberculous guinea-pigs and rabbits. They concluded from these experiments that antigen thus prepared when injected into animals was capable of provoking an abundant production of antibodies to increase their resistance to tuberculosis. Doses
BOYD GL, PARSONS HC. TREATMENT OF EXTRAPULMONARY TUBERCULOSIS WITH METHYLATED ANTIGEN. Am J Dis Child. 1932;44(5):1007-1012. doi:10.1001/archpedi.1932.01950120089006