The effect of leptin on engraftment in patients undergoing peripheral blood stem cell transplantation

To evaluate the alterations of serum leptin levels during stem cell transplantation and its possible role in engraftment. Thirty-two patients (19 male, 13 female) with various hematological and solid tumors and 28 healthy subjects (15 male, 13 female) as a control group were enrolled in the study.

Serum leptin levels were measured on the day before administering G-CSF, at the time of leukapheresis harvest, on day +1st and +7th after transplantation and on the day of leukocyte engraftment.

There was no significant difference in serum leptin levels between patients (mean +/- SEM, 11.62 +/- 2.75 ng/ml) before transplantation and control groups (9.79 +/- 1.73 ng/ml). Pre-G-CSF (baseline) level of serum leptin (11.62 +/- 2.75 ng/ml) was significantly decreased to 7.73 +/- 2.02 ng/ml at the time of apheresis harvest (P = 0.0029). Later, serum leptin levels increased to 16.75 +/- 3.26 ng/ml on day +1 after transplantation (P < 0.0001). Subsequently serum leptin levels both on day +7th posttransplant (12.11 +/- 2.17 ng/ml) and leukocyte engraftment day (9.26 +/- 1.50 ng/ml) were gradually decreased. There was no correlation between the serum leptin levels and the leukocyte or platelet engraftment.

The present study concludes that serum leptin level does not change remarkably during peripheral blood stem cell transplantation and no association exists between circulating leptin levels and the onset of engraftment suggesting that circulating serum leptin does not have a significant direct influence on engraftment.