With favorable regenerative and immunotolerant profiles, patient-derived human mesenchymal stem cells (hMSCs) are increasingly considered in cell therapy. Derived from bone marrow (BM) and standardized with culture in fetal bovine serum (FBS), translation of hMSC-based approaches is impeded by protracted expansion times, risk of xenogenic response, and exposure to zoonoses. Here, human platelet lysate adherent to good manufacturing practices (GMP-hPL) provided a nonzoonotic adjuvant that enhanced the capacity of BM-hMSC to proliferate. The nurturing benefit of GMP-hPL was generalized to hMSC from adipose tissue evaluated as an alternative to bone marrow. Long-term culture in GMP-hPL maintained the multipotency of hMSC, while protecting against clonal chromosomal instability detected in the FBS milieu. Proteomic dissection identified TGF-β, VEGF, PDGF, FGF, and EGF as highly ranked effectors of hPL activity, revealing a paradigm of healing that underlies platelet lysate adjuvancy. Thus, GMP-adherent human platelet lysate accelerates hMSC proliferation with no chromosomal aberrancy, through an innate repair paradigm.

The global impetus to identify curative therapies has been fuelled by the unmet needs of patients in the context of a growing heart failure pandemic. To date, regeneration trials in patients with cardiovascular disease have used stem-cell-based therapy in the period immediately after myocardial injury, in an attempt to halt progression towards ischaemic cardiomyopathy, or in the setting of congestive heart failure, to target the disease process and prevent organ decompensation. Worldwide, several thousand patients have now been treated using autologous cell-based therapy; the safety and feasibility of this approach has been established, pitfalls have been identified, and optimization procedures envisioned. Furthermore, the initiation of phase III trials to further validate the therapeutic value of cell-based regenerative medicine and address the barriers to successful clinical implementation has led to resurgence in the enthusiasm for such treatments among patients and health-care providers. In particular, poor definition of cell types used, diversity in cell-handling procedures, and functional variability intrinsic to autologously-derived cells have been identified as the main factors limiting adoption of cell-based therapies. In this Review, we summarize the experience obtained from trials of 'first-generation' cell-based therapy, and emphasize the advances in the purification and lineage specification of stem cells that have enabled the development of 'next-generation' stem-cell-based therapies targeting cardiovascular disease.

The BubR1 gene encodes for a mitotic regulator that ensures accurate segregation of chromosomes through its role in the mitotic checkpoint and the establishment of proper microtubule-kinetochore attachments. Germline mutations that reduce BubR1 abundance cause aneuploidy, shorten lifespan, and induce premature aging phenotypes and cancer in both humans and mice. Reduced BubR1 expression is also a feature of chronological aging, but whether this age-related decline has biological consequences is unknown. Using a transgenic approach in mice, we show that sustained high expression of BubR1 preserves genomic integrity and reduces tumorigenesis, even in the presence of genetic alterations that strongly promote aneuplodization and cancer, such as oncogenic Ras. We find that BubR1 overabundance exerts its protective effect by correcting mitotic checkpoint impairment and microtubule-kinetochore attachment defects. Furthermore, sustained high expression of BubR1 extends lifespan and delays age-related deterioration and aneuploidy in several tissues. Collectively, these data uncover a generalized function for BubR1 in counteracting defects that cause whole chromosome instability and suggest that modulating BubR1 provides a unique opportunity to extend healthy lifespan.

Objective The goal of this study was to guide bone marrow-derived human mesenchymal stem cells (hMSC) into a cardiac progenitor phenotype, and assess therapeutic benefit in chronic myocardial infarction. Background Adult stem cells, delivered in their naïve state, demonstrate a limited benefit in patients with ischemic heart disease. Preemptive lineage pre-specification may optimize therapeutic outcome. Methods hMSC were harvested from a coronary artery disease patient cohort. A recombinant cocktail consisting of TGFβ1, BMP-4, Activin-A, retinoic acid, IGF-1, FGF-2, α-thrombin and IL-6 was formulated to engage hMSC into cardiopoiesis. Derived hMSC were injected into the myocardium of a nude infarcted murine model, and followed over 1-year for functional and structural end-points. Results While the majority of patient-derived hMSC in their native state demonstrated limited effect on ejection fraction, stem cells from rare individuals harbored a spontaneous capacity to improve contractile performance. This reparative cytotype was characterized by high expression of Nkx2.5, Tbx5, Mesp-1 and Mef2C, markers of cardiopoiesis. Recombinant cardiogenic cocktail guidance secured the cardiopoietic phenotype across the patient cohort. Compared to unguided counterparts, cardiopoietic hMSC delivered into infarcted myocardium achieved superior functional and structural benefit without adverse side effects. Engraftment into murine hearts was associated with increased human-specific nuclear, sarcomeric and gap junction content along with induction of myocardial cell cycle activity. Conclusions Guided cardiopoiesis thus enhances the therapeutic benefit of bone marrow-derived human mesenchymal stem cells in chronic ischemic cardiomyopathy.

The C-CURE trial implements the paradigm of lineage guidance in cell therapy. Cardiopoietic stem cell therapy was found feasible and safe with signs of benefit in chronic heart failure, meriting definitive clinical evaluation. (C-Cure Clinical Trial; NCT00810238).