Impaired macrophage and memory T-cell responses to Bacillus Calmette-Guerin nonpolar lipid extract.

Introduction: The attenuation of BCG has led to the loss of not only immunogenic proteins but also lipid antigens.

Methods: Thus, we compared the macrophage and T-cell responses to nonpolar lipid extracts harvested from BCG and () to better understand the role of BCG lipids in the already known diminished responses of the vaccine strain.

Results: Relative to Mtb, nonpolar lipid extract from BCG presented a reduced capacity to trigger the expression of the genes encoding TNF, IL-1b, IL-6 and IL-10 in RAW 264.