Saturated phospholipids are required for nano- to micron-size transformation of cholesterol-containing liposomes upon QS21 addition

Abstract

Liposomes containing cholesterol and monophosphoryl lipid A (such as ALFQ and AS01B) are vaccine adjuvants. During construction of the formulations, addition of QS21 to nano-size (50–100 nm) liposomes resulted in extremely large (up to ∼30 µm) liposomes in ALFQ, but AS01B liposomes remained small nano-vesicles. Here, we show that saturation of phospholipid chains is essential for production of large liposomes by QS21.

Keywords:

• AS01B
• army liposome formulation containing QS21 (ALFQ)
• monophosphoryl lipid A
• QS21
• vaccine adjuvant
• 3D-PHAD^®

Acknowledgments

This work was supported through a Cooperative Agreement Award (No. W81XWH-07–2-067) between the Henry M. Jackson Foundation for the Advancement of Military Medicine and the U.S. Army Medical Research and Materiel Command (MRMC). The views expressed in this article are those of the authors and do not necessarily reflect the official policy of the Department of the Army, Department of Defense, or the U.S. Government.

Declaration of interest

CRA and ZB are co-inventors on a pending patent for ALFQ.

Additional information

Funding

Cooperative Agreement Award (No. W81XWH-07-2-067) between the Henry M. Jackson Foundation for the Advancement of Military Medicine and the U.S. Army Medical Research and Materiel Command (MRMC).