A Purified Recombinant Lipopeptide as Adjuvant for Cancer Immunotherapy
Figure 1
The lipid structures of Pam3CSK4 and Triacyl-CysSQEAK (lipo-Nter). (a) Identification of purified lipo-Nter by mass spectrometry. Lipo-Nter was obtained after trypsinizing rlipo-D1E3 and was analyzed on a Waters MALDI micro MX mass spectrometer. The MALDI-TOF MS spectra revealed the existence of four peaks with m/z values of 1451.9, 1465.9, 1479.9, and 1493.9. (b) Pam3CSK4 contains an N-acyl-S-diacylglyceryl cysteine moiety, and the fatty acids in all of the groups are 16-carbon saturated fatty acids. (c) The lipid structure of lipo-Nter is also an N-acyl-S-diacylglyceryl cysteine structure. The R2 group of lipo-Nter contains unsaturated fatty acids with different chain lengths. (d) The masses of Pam3CSK4 and lipo-Nter were determined. We previously [23] identified the masses of the corresponding lipid structures.
