Figure 1. Schematic representation of the methodology used for the enrichment and analysis of the putative T. cruzi PAF-like phospholipid.

The total lipid content of the pellets from T. cruzi epimastigote (Epi), metacyclic trypomastigote (Meta), tissue culture-derived trypomastigote (TCT), or intracellular amastigote (ICA) forms was extracted with organic solvents followed by Foch's partition. Folch lower-phase samples were fractionated by SPE in a silica gel (60 Å) column. The different lipid classes were eluted with chloroform (neutral lipids), acetone (glycolipids), and methanol (phospholipids). The latter was further fractionated by perfusion chromatography using POROS R1 50 mini-columns, eluted with a 0%–50% n-propanol gradient. All fractions were diluted in methanol containing 5 mM LiOH and analyzed by MSⁿ. The inset depicts the T. cruzi life cycle with the four stages used in this study.