Intermittent Hypoxia Affects the Spontaneous Differentiation In Vitro of Human Neutrophils into Long-Lived Giant Phagocytes

Figure 2

Effects of chronic and acute hypoxia on the development of giant phagocytes (Gϕ). (a) A typical profile of 10 intermittent hypoxia (IH) cycles. During IH actual % O₂ in the medium (solid line) decreased to 5% oxygen concentration during the hypoxia. In the reoxygenation period O₂ levels reached 20% oxygen. (b) For chronic hypoxia treatments, PMN were exposed to 29 cycles (approximately 12 h) of IH/day for 5 days or to a comparable time of sustained hypoxia (SH)/day. Controls were maintained at normoxia for the entire period. (c) For acute hypoxia treatments, PMN were exposed to 10 IH cycles (250 min), 29 IH cycles (approximately 12 h), or 56 IH cycles (approximately 24 h), each in the first day in culture. SH was employed for comparable times at 5% actual oxygen in the medium for the entire period (12 h and 24 h) and control cells were maintained at normoxia. Thereafter, the hypoxia treated cells were transferred to normoxia for additional six days. Light microscopy of living culture. Representative data out of 3 independent experiments. In (b) and (c) is bright-field microscopy of living cells.

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