Granulocyte-colony stimulating factor improves suppressed neutrophilic phagocytosis against hypernatremic condition

Phagocytic activity is an important function of neutrophils in the host defense against burn wound infection. In a previous report we demonstrated hypernatremic suppression of neutrophils at sodium concentrations comparable to these in the zone of stasis in the burn wound. At this site the osmotic pressure will be elevated as a result of several factors, especially to increased water loss from the burn wound surface. In this study the effect of granulocyte-colony stimulating factor (G-CSF) on phagocytic activity of human neutrophils against hypernatremic suppression is investigated in vitro. In the G-CSF group 150 ng of G-CSF was added to four blood samples (5 ml each). Phagocytic activities of the control group (n = 10) showed 88.3+/-4.1 per cent (means+/-SD) at 140 mmol/l of sodium concentration, 68.2+/-6.9 at 180, 57.6+/-10.1 at 220, and 48.6+/-8.6 at 260 mmol/l. The G-CSF group showed 88.2+/-7.0 at 140, 79.9+/-9.4 at 180, 71.4+/-7.4 at 220, and 56.5+/-14.1 at 260 mmol/l. At 180 and 220 mmol/l significant differences were recognized. Results of this study suggest a favourable effect of G-CSF on suppressed neutrophils under the hypernatremic conditions.