RESUMEN
The pro-angiogenic abilities of adipose-derived stromal cells (ASCs) make them attractive candidates for cellular therapy, especially for ischemic disease indications. However, details regarding the underlying mechanisms remain elusive. Therefore, this study aimed to investigate paracrine and juxtacrine abilities of ASCs in angiogenesis triple cell co-cultures by detailed image analysis of the vascular-like structures. Fibroblast-endothelial cell co-cultures were established, and ASCs were added directly or indirectly through inserts. The cultures were treated with antibodies or subjected to analyses using ELISA and RT2 PCR Arrays. The model consistently generated vascular-like structures. ASCs increased the total branch lengths equally well in paracrine and juxtacrine conditions, by increasing the number of branches and average branch lengths (ABL). In contrast, addition of VEGF to the model increased the number of branches, but not the ABL. Still, ASCs increased the VEGF levels in supernatants of paracrine and juxtacrine co-cultures, and anti-VEGF treatment decreased the sprouting. ASCs themselves up-regulated collagen type V in response to paracrine signals from the co-cultures. The results suggest that ASCs initiate sprouting through secretion of several paracrine factors, among which VEGF is identified, but VEGF alone does not recapitulate the paracrine actions of ASCs. By employing neutralizing antibodies and dismantling common model outputs using image analysis, the triple cell co-culture is an attractive tool for discovery of the paracrine factors in ASCs' secretome which act in concert with VEGF to improve angiogenesis.
Asunto(s)
Tejido Adiposo , Técnicas de Cocultivo , Neovascularización Fisiológica , Comunicación Paracrina , Células del Estroma , Humanos , Células del Estroma/metabolismo , Células del Estroma/citología , Tejido Adiposo/citología , Tejido Adiposo/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Células Endoteliales/metabolismo , Células Endoteliales/citología , Células Cultivadas , Fibroblastos/metabolismo , Fibroblastos/citología , AngiogénesisRESUMEN
The present first-in-human clinical trial evaluated the safety and feasibility of a newly developed and cryopreserved Cardiology Stem Cell Centre adipose-derived stromal cell (CSCC_ASC) product from healthy donors for intramyocardial injection in ten patients with ischemic heart disease and ischemic heart failure (IHF). Batches of CSCC_ASC were isolated from three healthy donors by liposuction from abdominal adipose tissue. Adipose mesenchymal stromal cells were culture expanded in bioreactors without the use of animal constituents, cryopreserved, and stored in vials in nitrogen dry-storage containers until use. Direct injection of CSCC_ASC into the myocardium did not cause any complications or serious adverse events related to either treatment or cell administration in a 6-month follow-up period. Four out of ten heart failure patients developed donor-specific de novo human leukocyte antigen (HLA) class I antibodies, and two out of ten patients had donor-specific HLA antibodies already at baseline. There were no clinical symptoms or changes in inflammatory parameters in the follow-up period that indicated an ongoing immune response. There was a tendency toward improvement in cardiac function after CSCC_ASC treatment at 6-month follow-up: left ventricular end systolic volume decreased and left ventricular ejection fraction increased. In addition, exercise capacity increased. These changes were independent of the presence or absence of HLA antibodies. It is concluded that the newly developed cryopreserved product CSCC_ASC from healthy donors was a safe and feasible treatment. We observed a tendency toward efficacy in patients with IHF. These findings have to be confirmed in larger placebo controlled clinical trials. Stem Cells Translational Medicine 2017;6:1963-1971.