Factors predicting peripheral blood progenitor cell mobilization in healthy donors in the era of related alternative donors: Experience from a single center.

BACKGROUND

Poor mobilization results are unexpected after G-CSF-induced peripheral blood stem cell collection in healthy donors. However, 2%-5% of the donors are poor mobilizers. Factors predicting CD34+-cell yield after mobilization in related alternative donors are still poorly known.

PATIENTS AND METHODS

Baseline characteristics and efficacy results of G-CSF induced mobilization of 159 adult healthy donors in our institution from 2008 to 2016 were retrospectively analyzed. All donors received 10 μg/kg of G-CSF once a day subcutaneously for 4 days. Leukapheresis started on the 5th day of G-CSF treatment. Donors were classified as poor mobilizers if they had less than 20 000 CD34 + cell/mL peripheral blood count in the 5th day of G-CSF treatment or if they needed three or more leukapheresis for graft collection.

RESULTS

Age, weight, and platelet count before and after mobilization were significantly different between poor and good mobilizers. Poor mobilizers (n = 16) were older (50.6 vs 41.7 years, P = 0.002), weight lower (64 vs 75 kg, P = 0.00) and showed a lower platelet count before (199.5 vs 219.0 × 10 /L, P = 0.03) and after (192.5 vs 206 × 10 /L, P = 0.019) mobilization. In the multivariate analysis only the 30% of the variability of mobilization was explained by the model (sensitivity 80%, specificity 70%).

CONCLUSION

In this cohort of healthy donors in a single institution, older age, less weight, and lower platelet count was associated with poorer mobilization. With clinical and analytic factors it is not possible to predict more than 30% of the variability. Further studies are needed to investigate new variables.