EFFICACY OF PENTASTARCH IN GRANULOCYTE COLLECTION BY CENTRIFUGAL LEUKAPHERESIS

The efficacy of 6% hydroxyethyl starch (hetastarch, HS) in enhancing g ranulocyte harvest by centrifugal leukapheresis has been described by a simple equation which predicts the granulocyte collection efficiency (GCE) based on an intrinsic donor variable, the erythrocyte sedimenta tion rate (ESR): GCE (%) = 1.3 ESR (mm/hr) + 45. Ten percent low molec ular weight hydroxyethyl starch (pentastarch, PS) has been reported to be as effective as HS with potentially fewer adverse donor reactions (ADR). The derivation of an analogous equation for PS under conditions previously reported for HS may quantify PS efficacy and allow compari son to HS. We prospectively measured the in vitro and the in vivo effe cts of PS on the donor ESR in 53 granulocyte collections from 44 donor s using the model CS-3000 Plus blood cell separator (CS). We then corr elated the findings with the GCE of each procedure and derived an equa tion which expresses GCE in terms of baseline donor ESR. The in vitro addition of PS increased the donor ESR 2.4-fold, but its administratio n to a donor during a collection procedure did not appreciably change the ESR. Higher baseline donor ESR was more likely to result in more e fficient cell collections: GCE (%)= 0.8 ESR (mm/hr) + 20; (r = 0.37). For granulocyte harvests using the CS and PS as the sedimenting agent 1) baseline donor ESR affects granulocyte harvests, but the poor corre lation does not allow an accurate prediction of GCE and cell yield fro m the baseline donor ESR; 2) in comparison with HS (results from a pre vious study), PS may be less effective in vitro and not effective in v ivo in elevating ESR, and may be less effective in enhancing granulocy te harvest; and 3) the parameters (slope, y-intercept, correlation coe fficient) which define the linear relationship between baseline donor ESR and GCE may serve collectively as a quantitative measure of the ef fectiveness of different hydroxyethyl starch agents in enhancing granu locyte harvests. These parameters may be helpful in rapidly assessing the clinical efficacy of new, potentially useful hydroxyethyl starch a gents prior to initiating a randomized, controlled clinical trial. (C) 1995 Wiley-Liss, Inc.