Figure 6
Lactate/pyruvate time intensity curves, (EJ 28Luc: A controls, B treated; LN18: E controls, F treated), AUC ratios (C: EJ28Luc, G: LN18) and kpl values (D: EJ28Luc, H: LN18) after treatment with 213Bi-anti-EGFR-MAb via detection of hyperpolarized [1-13C]-labeled compounds. For determination of cellular lactate/pyruvate ratios, LN18 and EJ28Luc cells were incubated either with PBS (control) or 213Bi-anti-EGFR-MAb, harvested after 48 h and transferred to NMR tubes. After polarization of [1-13C]pyruvate in a DNP polarizer for 35 min, the hyperpolarized [1-13C]pyruvate was rapidly injected into the NMR tube containing the cells and transferred into a magnetic resonance spectrometer for detection of pyruvate to lactate conversion. Corresponding sample time intensity curves are shown for EJ28Luc (A,B) and LN18 (E,F) cells, indicating an increase of lactate after treatment with 213Bi-anti-EGFR-MAb. Incubation with 213Bi-anti-EGFR-MAb increased lactate/pyruvate ratios in both cell lines compared to PBS-treated controls (C EJ28Luc, G LN18). 213Bi-anti-EGFR-MAb treatment primarily triggered an increase in the lactate formation in both cell lines that resulted in an increase of the kpl values as indicated in D and H. Displayed are mean ± SD.
