Description and references

A filtrate from triturated Mycobacteria tuberculosis. Old Tuberculin is the culture filtrate prepd by boiling and then filtering the M. tuberculosis culture. Purified protein derivative is a more refined tuberculin prepd by precipitating the culture filtrate with ammonium sulfate. Purification and dermal reactivity: F. B. Seibert, J. T. Glenn, Am. Rev. Tuberc. 44, 9 (1941). Review of tuberculin skin test: G. W. Comstock et al., Am. Rev. Respir. Dis. 124, 356 (1981).

Derivative