Preconditioning of Human Dental Pulp Stem Cells with Leukocyte- and Platelet-Rich Fibrin-Derived Factors Does Not Enhance Their Neuroregenerative Effect

Figure 6

The effect of CM-hDPSCs and prCM-hDPSCs on neurite outgrowth of pCNs. Compared to controls, CM-hDPSCs but not prCM-hDPSCs () was able to stimulate total neurite outgrowth per neuron (a) and the mean length of the longest neurite (b). The fraction of interconnecting cells was determined as a measurement for cells contributing to network formation (c). These data showed that CM-hDPSCs and prCM-hDPSCs were both able to stimulate neuronal network formation. The effect of CM-hDPSCs and prCM-hDPSCs is not due to an increase in the number of pCN neurites as the number of neurites per pCN is not affected (d). Exposure to CM-hDPSCs or prCM-hDPSCs did not have an influence on the neuronal content of the cell cultures (e) or neuronal death (f) 72 h after exposure as measured by the fraction of β-III tubulin-positive cells and pyknotic β-III tubulin-positive cells, respectively. Representative micrographs of β-III tubulin-stained pCNs after exposure to control medium (g), CM-hDPSCs (h), and prCM-hDPSCs (i). value ≤ 0.05; value ≤ 0.001. Data are expressed as . Scale bars: g–i: 50 μm.

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