Figure 4. PHD3^−/− BMDM are protected from apoptotic cell death.

(A) PHD3^−/− and WT BMDM were cultivated, with or without serum (starved). After 48 h, the number of apoptotic cells was quantified by TUNEL and Annexin V (AV) stainings. (B) Forty-eight hours after starvation, cell viability was determined using the calcein-AM viability assay. (C) The number of Annexin V-positive cells was quantified after cultivating PHD3^−/− and WT BMDM, with or without serum, for 48 h or treating the cells with 100 μM SNAP, 500 nM stauro, or 5–10 μg/mL LPS for 12 h. (D) The number of Annexin V-positive cells was quantified after cultivating PHD3^−/− and WT BMDM, with or without serum, for 48 h at 20% O₂ or 1% O₂; n = 5 for Annexin V stainings; all others, n = 3; mean ± sd; *P < 0.05, **P < 0.01, and ***P < 0.001.