Cardiac progenitor cells (CPCs) isolated as cardiospheres (CSs) and CS-derived cells
April 2, 2017
Cardiac progenitor cells (CPCs) isolated as cardiospheres (CSs) and CS-derived cells (CDCs) are a promising tool for cardiac cell therapy in heart failure patients having CDCs already been used in a phase PD 0332991 HCl I/II clinical trial. optimally in terms of CPCs yield/phenotype. In conclusion the use of HSs for the isolation and growth of CSs/CDCs has to be excluded because of altered proliferation and/or commitment while media supplemented with B27 and the selected giFBS allows successful EU GMP-complying CPCs culture. 20 Reduced proliferation of CDCs in HS was consistent with the observed morphology (Fig.?4E): as seen in main explant cultures CDCs in HSs assumed a senescent-like shape and eventually stopped proliferating at early passage. Physique 3 Cultures with commercial AB human sera gradually displayed senescence features. Initial cell growth in main explants was comparable between foetal bovine serum (FBS) and HSs as exhibited by time-course of cell harvests (H) up PD 0332991 HCl to H2 (A) and comparable … Physique 4 Cardiospheres (CSs) yield and cell proliferation in AB human sera cultures. CSs yield and dimension expressed as percentage of effect foetal bovine serum (FBS) were comparable in human serum (HSs) cultures (A) until CS-forming cells could be … Gene expression analysis was performed on CDCs from HS cultures and normalized to standard FBS (Fig.?5A). Clean muscle mass actin (SMA) and Thy1 levels were significantly down-regulated in both HSs while cardiac markers such as TnI and Cx43 were basically unaffected. Analysis of Hsps expression levels suggests no changes in cell stress. Interestingly KDR was dramatically up-regulated in both HSs suggesting that HSs could encourage endothelial commitment of CDCs. This hypothesis was further supported by immunofluorescence analysis of CSs (Fig.?5B) which showed especially for Starfish serum a strong and homogeneous positivity for CD31. The expression of TnI and Nkx2.5 proteins was PD 0332991 HCl confirmed by immunofluorescence as well. Physique 5 Cardiac progenitor cells in AB human sera displayed altered commitment towards cardiovascular lineages. Gene expression analysis on CS-derived cells (CDCs; A) normalized to standard foetal bovine serum (FBS) conditions revealed a significant up-regulation … To test whether the HS unfavorable effect could be reduced or avoided by decreasing serum concentration from the beginning of the protocol PD 0332991 HCl an attempt was made to culture main explants in 1% or 3% HS but no cells could be obtained (Physique?S1). Moreover to test whether residual match activity could be responsible for the growth arrest and phenotype switch observed we tested Lonza HS after warmth inactivation treatment. CDCs from normal FBS explants were plated for 7?days in FBS 5% as control Lonza HS 20% or 5% Lonza HS warmth inactivated 20% or 5% and gene expression analysis was performed by realtime PCR and normalized to standard FBS 20% conditions. As shown in Physique?5C even on normal healthy CDCs 1 of culture in HS was enough to significantly modulate gene expression. In Lonza HS 20% SMA ckit TnI Cx43 Thy1 and Gata4 were significantly down-regulated while KDR levels were unchanged confirming again a possible preferential endothelial commitment exerted by HS. As observed for cell proliferation a dose-dependent effect was detected as demonstrated from your analysis of the Lonza HS 5% sample where most genes inverted the down-regulation pattern. Genes down-regulation was still detectable in heat-inactivated HS displaying again an inverted dose-dependent pattern from 20% to 5%. Nevertheless important genes such as SMA c-kit and Cx43 were still significantly down-regulated compared with standard FBS conditions. PD 0332991 HCl Gamma-irradiated FBS As human sera exerted inhibitory/harmful effects on our cellular model and altered commitment we next examined the possibility of using GMP gamma-irradiated FBS (giFBS) of TPO Australian origin. We evaluated sera from three different companies Lonza Gibco and Hyclone on eight different biopsies overall. Considering Gibco and Lonza we were able to isolate CPCs from three out of five and two out of five explants respectively while all control explants in FBS yielded successful CPCs isolation. With these two sera we observed again a pattern of senescent-like morphology with time in culture (Physique?S1A). Average CSs yield and dimension were not significantly different from standard FBS (Physique?S1B) but the overall rate of successful explants was clearly unsatisfactory. Hyclone explants were all successful with comparable timing (Table S3) and yield (Physique?S1B) standard FBS and did not.