Preliminary findings on the use of pulsatile machine reperfusion of a placenta to improve the cord blood collection yield including primitive hematopoietic stem cell fractions

Abstract

Umbilical cord blood (CB) use is limited in most adults since the mean amount of hematopoietic stem cells (HSCs) collected is generally insufficient to engraft successfully. This study demonstrates for the first time the feasibility of pulsatile machine placenta reperfusion (PMPR), which significantly improves CB collection quantity and quality compared to standard collection methods. PMPR was performed on eight delivered placentas up to 39 hours after venipuncture-based collection. PMPR was performed on average for 26 (20-30) minutes, 17 hours after delivery (6.25-39), using perfusate approved for donated organ reperfusion. Both PMPR and conventional collection-derived CB cells were analyzed using immunophenotyping and colony assays. The combination of PMPR and the conventional venipuncture method yielded a mean of 1.5-, 4.9-, 11-, 7.5-, 7.5-, and 7.7-fold increased number of total mononuclear, CD34+, CD34+/CD38-, CD133+, CD133+/CD34+, and CD133+/CD34- cells, respectively, compared to conventional venipuncture alone. CB cells obtained by PMPR alone generally demonstrated a significant increase in percentages of primitive HSC phenotype with equivalent cell viability between PMPR and venipuncture. This article demonstrates for the first time that CB can be collected up to 39 hours after delivery with PMPR while maximizing CB collection including HSCs with primitive phenotypes.