Expired and Pathogen-Inactivated Platelet Concentrates Support Differentiation and Immunomodulation of Mesenchymal Stromal Cells in Culture

Abstract

Platelet lysates have been reported as suitable cell culture supplement for cultures of mesenchymal stromal cells (MSCs). The demand for safe and animal-free cultures of MSCs is linked to the potential application of MSCs in clinics. While the use of platelet lysates offers an alternative to animal serum in MSC cultures, obtaining supplies of fresh platelet concentrates for lysate production is challenging and raises concerns due to the already existing shortage of platelet donors. We have previously demonstrated that expired platelet concentrates may represent a good source of platelets for lysate production without competing with blood banks for platelet donors. The INTERCEPT Blood System™ treatment of platelet concentrates allows for prolonged storage up to 7 days, using highly specific technology based on amotosalen and UV-A light. The INTERCEPT system has therefore been implemented in blood processing facilities worldwide. In this study, we evaluated the suitability of INTERCEPT-treated, expired platelet concentrates, processed into platelet lysates, for the culture of MSCs compared to nontreated expired platelets. Bone marrow-derived MSCs were cultured in media supplemented with either platelet lysates from traditionally prepared expired platelet concentrates or in platelet lysates from expired and pathogen-inactivated platelet concentrates. The effects of pathogen inactivation on the ability of the platelets to support MSCs in culture were determined by evaluating MSC immunomodulation, immunophenotype, proliferation, and trilineage differentiation. Platelet lysates prepared from expired and pathogen-inactivated platelet concentrates supported MSC differentiation and immunosuppression better compared to traditionally prepared platelet lysates from expired platelet units. Pathogen inactivation of platelets with the INTERCEPT system prior to use in MSC culture had no negative effects on MSC immunophenotype or proliferation. In conclusion, the use of expired pathogen-inactivated platelet units from blood banks to prepare platelet lysates for the culture of MSCs is desirable and attainable.

Viral inactivation of human platelet lysate by gamma irradiation preserves its optimal efficiency in the expansion of human bone marrow mesenchymal stromal cells

“…16 Moreover, it has already been described that hPL prepared from THERAFLEX UV-Platelets-or Intercepttreated PCs is as efficient as non-inactivated hPL to promote BM-hMSC proliferation. [17][18][19][20] Some viruses may be resistant to these technologies, for instance, HAV for Intercept and Mirasol 21 and HIV-1 for THERAFLEX UV-Platelets. 22 Moreover, Intercept and Mirasol technologies imply the use of a nucleic acid intercalating agent.…”

Venous Blood Derivatives as FBS-Substitutes for Mesenchymal Stem Cells: A Systematic Scoping Review

“…FBS is the most applied supplement for MSC culture comprising a complex mixture of growth factors (GF), proteins, carbohydrates and cytokines indispensable for cell development and survival in vitro (12)(13)(14). However, FBS presents risks regarding pathogens transmissions and internalization of animal's proteins, which can unleash antigenic responses in the patient after MSC implantation (9,15). Animal-derived (or xenogeneic) proteins can be detected in human MSC expanded in FBS, even after consecutive cell washings (9).…”

A double‐virally‐inactivated (Intercept–solvent/detergent) human platelet lysate for in vitro expansion of human mesenchymal stromal cells

“…Outdated human platelet concentrates (PCs) can be used to prepare “human platelet lysate (HPL)” . HPL is a complex protein fluid, rich in platelet (PLT) growth factors and cytokines, that is an excellent substitute for fetal bovine serum (FBS) to supplement growth media for the expansion of mesenchymal stromal cells (MSCs) in vitro .…”