Extended Data Fig. 2: HPLC fractionation of P2RY8 bioactivity from bile and Q1 mass spectrometry candidate identification.
From: S-Geranylgeranyl-l-glutathione is a ligand for human B cell-confinement receptor P2RY8
a, Preparation of a concentrated bile extract from the Folch upper layer described in Extended Data Fig. 1d using acid precipitation, centrifugation and C18 SPE. b, HPLC chromatograms (blue) showing absorbance at 220 nm for each column used for fractionation. Columns were initially tested with a small amount of extract to determine the interval in which bioactivity eluted. The bioactivity graphs (red) that correspond to 1-min fractions are overlaid for the bioactive interval and represent the percentage of P2RY8+ cells that are inhibited in their migration towards CXCL12 in the P2RY8 ligand bioassay. c, Full scan (Q1) mass spectra of purified fractions from the indicated conditions, in negative-ion mode. Zoomed-in spectra of m/z values of 550–600 are shown directly below each Q1 scan. Data are representative of two (a, b) or one (c) independent experiments.
