Human Platelet Lysate for Good Manufacturing Practice-Compliant Cell Production

Abstract

Numerous cell-based therapeutics are currently being tested in clinical trials. Human platelet lysate (HPL) is a valuable alternative to fetal bovine serum as a cell culture medium supplement for a variety of different cell types. HPL as a raw material permits animal serum-free cell propagation with highly efficient stimulation of cell proliferation, enabling humanized manufacturing of cell therapeutics within a reasonable timeframe. Providers of HPL have to consider dedicated quality issues regarding identity, purity, potency, traceability and safety. Release criteria have to be defined, characterizing the suitability of HPL batches for the support of a specific cell culture. Fresh or expired platelet concentrates from healthy blood donors are the starting material for HPL preparation, according to regulatory requirements. Pooling of individual platelet lysate units into one HPL batch can balance donor variation with regard to essential platelet-derived growth factors and cytokines. The increasingly applied pathogen reduction technologies will further increase HPL safety. In this review article, aspects and regulatory requirements of whole blood donation and details of human platelet lysate manufacturing are presented. International guidelines for raw materials are discussed, and defined quality controls, as well as release criteria for safe and GMP-compliant HPL production, are summarized.

Keywords: cell therapy; good manufacturing practice (GMP); human platelet lysate (HPL); platelet concentrates; regeneration; regenerative medicine.

Figure 1

Preparation of pooled human platelet lysate (HPL). Fresh or expired platelet concentrates are exposed to freezing/thawing for platelet lysis. Ten units of platelet lysates are pooled in one bag and further portioned. After a second freeze/thaw step, the bags are centrifuged to deplete the platelet fragments. Final vials of pooled HPL are stored at least at −30 °C until use.