Replacing FBS with HPL prevents bovine prion, viral, and zoonose contamination of the stem cell product. This new efficient FBS-free two-step procedure for clinical-scale MSC propagation may represent a major step toward challenging new stem cell therapies.

In healthy adults, sclerostin serum levels correlate positively with age, BMI, and BMC and negatively with osteocalcin and calcium. Further studies in larger populations are needed to confirm our findings and to better understand their clinical implications.

Adult mesenchymal stem cells (MSCs) are considered as valuable mediators for tissue regeneration and cellular therapy. This study was performed to develop conditions for regularly propagating a clinical quantity of > 2 x 10(8) MSCs without animal serum from small bone marrow (BM) aspiration volumes within short time. We established optimized culture conditions with pooled human platelet lysate (pHPL) replacing fetal bovine serum (FBS) for MSC propagation. MSC quality, identity, purity, and function were assessed accordingly. Biologic safety was determined by bacterial/fungal/mycoplasma/endotoxin testing and genomic stability by array comparative genomic hybridization (CGH). We demonstrate that unmanipulated BM can be used to efficiently initiate MSC cultures without the need for cell separation. Just diluting 1.5-5 mL heparinized BM per 500 mL minimum essential medium supplemented with L-glutamine, heparin, and 10% pHPL sufficiently supported the safe propagation of 7.8 +/- 1.5 x 10(8) MSCs within a single 11- to 16-day primary culture under defined conditions. This procedure also resulted in sustained MSC colony recovery. MSC purity, immune phenotype, and in vitro differentiation potential fully matched current criteria. Despite high proliferation rate, MSCs showed genomic stability in array CGH. This easy single-phase culture procedure can build the basis for standardized manufacturing of MSC-based therapeutics under animal serum-free conditions for dose-escalated cellular therapy and tissue engineering.

No abstract

The release of B19 DNA-positive blood products with a concentration of less than 105 IU per mL is thought to be safe due to the high level of neutralizing VP2 antibodies and is currently examined in a donor recipient infectivity study. In contrast, blood products with a high B19 DNA concentration (> or =10(5) IU/mL), some of which did not contain neutralizing antibodies, were discarded to protect at risk individuals.