Preparation and growth factor characterization of cord blood-derived plasma, serum, growth factor-rich plasma and...

In recent years, there has been a significant decline in the demand for cord blood units (CBUs). This trend has led to cord blood banks (CBBs) exploring complementary uses of CBUs in order to exploit the full potential of this unique, valuable, and readily available product. The aim of this study was to establish standardized protocols for the preparation of four cord blood (CB) derivatives: plasma (CB-P), serum (CB-S), induced-serum (CB-IS) and growth factor-rich plasma (GFRP); to measure their respective growth-factor content and their potential as cell culture supplements, and finally, to identify the characteristics of each derivative beyond their growth-factor composition, in the context of optimizing CBBs resources.

To this end, CB plasma and serum were prepared and their concentrations for ten growth factors (TGF-β1, TGF-β2, TGF-β3, EGF, HGF, PDGF-BB, VEGF-A, VEGF-D, IGF-I, IGF-II) were determined using a multiplex bead array, and compared to adult plasma and serum. Protocols for the preparation of CB-IS and GFRP with reverse anticoagulation using CaCl₂·2H₂O were also established, and all four derivatives were compared for their EGF and TGF-β1 content by enzyme-linked immunosorbent assay (ELISA), and also for their cell culture supplement capacity.

CB plasma was shown to be richer than adult plasma for TGF-β2 and TGF-β3, with a lower concentration of IGF-I and IGF-II. CB serum was shown to be richer than adult serum for TGF-β2, TGF-β3, EGF, HGF, PDGF-BB, and VEGF-A and D, and poorer in IGF-I and II. The measure of EGF and TGF-β1 concentrations has shown that CB serum is the most concentrated (1874 pg/ml and 41 094 pg/ml) of the CB derivatives, followed by induced-serum (405 pg/ml and 16 735 pg/ml), growth factor-rich plasma (131 and 7947 pg/ml) and plasma (8 and 2845 pg/ml). All four CB derivatives were shown to be superior to FBS in sustaining cell growth at low doses.

Our study shows that four CB derivatives can be easily prepared and pooled to provide significant volume of products that vary in their growth factor composition. A cord blood bank interested in introducing such manufacturing will need to evaluate the financial and processing characteristics of each derivative. The use of standardized manufacturing protocols such as the ones we suggest could help research initiatives exploring the potential therapeutic uses of such rich and high-quality starting material.