Deciphering the proteome of the in vivo diagnostic reagent “purified protein derivative” from Mycobacterium tuberculosis.

Abstract

Purified protein derivative (PPD) has served as a safe and effective diagnostic reagent for 60 years and is the only broadly available material to diagnose latent tuberculosis infections. This reagent is also used as a standard control for a number of in vitro immunological assays. Nevertheless, the molecular composition and specific products that contribute to the extraordinary immunological reactivity of PPD are poorly defined. Here, a proteomic approach was applied to elucidate the gene products in the U.S. Food and Drug Administration (FDA) standard PPD-S2. Many known Mycobacterium tuberculosisT-cell antigens were detected. Of significance, four heat shock proteins (HSPs) (GroES, GroEL2, HspX, and DnaK) dominated the composition of PPD. The chaperone activities and capacity of these proteins to influence immunological responses may explain the exquisite solubility and immunological potency of PPD. Spectral counting analysis of three separate PPD reagents revealed significant quantitative variances. Gross delayed-type hypersensitivity (DTH) responses in M. tuberculosis infected guinea pigs were comparable among these PPD preparations; however, detailed histopathology of the DTH lesions exposed unique differences, which may be explained by the variability observed in the presence and abundance of early secretory system (Esx) proteins. Variability in PPD reagents may explain differences in DTH responses reported among populations.

Citation

Yun Sang Cho.; Dobos, K.M.; Prenn, J.; Hongliang Yang; Hess, A.; Rosenkrands, I.; Andersen, P.; Sung Weon Ryoo.; Bai, G.H.; Brennan, M.J.; Izzo, A.; Bielefeldt-Ohmann, H.; Belisle, J.T. Deciphering the proteome of the in vivo diagnostic reagent “purified protein derivative” from Mycobacterium tuberculosis. PROTEOMICS (2012) 12 (7) 979-991. [DOI: 10.1002/pmic.201100544]

Help us improve GOV.UK

Don’t include personal or financial information like your National Insurance number or credit card details.