Fighting for territories: time-lapse analysis of dental pulp and dental follicle stem cells in co-culture reveals specific migratory capabilities

Abstract

Stem cell migration is a critical step during the repair of damaged tissues. In order to achieve appropriate cell-based therapies for tooth and periodontal ligament repair it is necessary first to understand the dynamics of tissue-specific stem cell populations such as dental pulp stem cells (DPSC) and dental follicle stem cells (DFSC). Using time-lapse imaging, we analysed migratory and proliferative capabilities of these two human stem cell lines in vitro. When cultured alone, both DPSC and DFSC exhibited low and irregular migration profiles. In co-cultures, DFSC, but not DPSC, spectacularly increased their migration activity and velocity. DFSC rapidly surrounded the DPSC, thus resembling the in vivo developmental process, where follicle cells encircle both dental epithelium and pulp. Cell morphology was dependent on the culture conditions (mono-culture or co-culture) and changed over time. Regulatory genes involved in dental cell migration and differentiation such as TWIST1, MSX1, RUNX2, SFRP1 and ADAM28, were also evaluated in co-cultures. MSX1 up-regulation indicates that DPSC and DFSC retain their odontogenic potential. However, DPSC lose their capacity to differentiate into odontoblasts in the presence of DFSC, as suggested by RUNX2 up-regulation and TWIST1 down-regulation. In contrast, the unchanged levels of SFRP1 expression suggest that DFSC retain their potential to form periodontal tissues even in the presence of DPSC. These findings demonstrate that stem cells behave differently according to their environment, retain their genetic memory, and compete with each other to acquire the appropriate territory. Understanding the mechanisms involved in stem cell migration may lead to new therapeutic approaches for tooth repair. AbstractStem cell migration is a critical step during the repair of damaged tissues. In order to achieve appropriate cellbased therapies for tooth and periodontal ligament repair it is necessary first to understand the dynamics of tissuespecific stem cell populations such as dental pulp stem cells (DPSC) and dental follicle stem cells (DFSC). Using timelapse imaging, we analysed migratory and proliferative capabilities of these two human stem cell lines in vitro. When cultured alone, both DPSC and DFSC exhibited low and irregular migration profiles. In co-cultures, DFSC, but not DPSC, spectacularly increased their migration activity and velocity. DFSC rapidly surrounded the DPSC, thus resembling the in vivo developmental process, where follicle cells encircle both dental epithelium and pulp. Cell morphology was dependent on the culture conditions (mono-culture or co-culture) and changed over time.Regulatory genes involved in dental cell migration and differentiation such as TWIST1, MSX1, RUNX2, SFRP1 and ADAM28, were also evaluated in co-cultures. MSX1 up-regulation indicates that DPSC and DFSC retain their odontogenic potential. However, DPSC lose their capacity to differentiate into odontoblasts in the presence of DFSC, as suggested by RUNX2 up-regulation and TWIST1 downr...

Response Proliferative Capacity of Undifferentiated Stem Cells of Obtained Human Adult Dental Follicle

“…As well as in a study by Schiraldi et al (2012), [36] on the migratory capacity of stem cells from pulp and dental follicle, we also observed that stem cells from the dental follicle followed a circular motion and explored the local environment. Huang et al (2006) [37] found that 1 to 2 weeks after the beginning of culture, the cell colonies contained fibroblast-like shape, and this shape was retained after 5 or more passageways.…”

Hybrid Complexes of High and Low Molecular Weight Hyaluronans Highly Enhance HASCs Differentiation: Implication for Facial Bioremodelling

“…The final melting curve was performed from 55°C to 95°C. Samples were run in triplicates and the expression of specific mRNA relative to the control was determined after normalization with respect to HPRT housekeeping gene (internal control) [25]. The fold-change of mRNA expression of the genes under evaluation was calculated by using the 2 −∆∆ Ct comparative threshold method (∆Ct = difference of ∆Ct between treated cells and non-treated cells used as controls).…”

Human dental pulp stem cells cultured in serum-free supplemented medium

“…This chemokine is associated with neuroinflammatory responses and could be involved in guiding neural progenitors to sites of brain damage (Tran et al, 2007). Growing number of studies indicates that MSCs home to sites of injury in response to cytokines and chemokines through the expression of their receptors (Schiraldi et al, 2012). CXC chemokine ligand 10 (CXCL10/IP-10) chemoattracts CXCR3-positive cells during pulpal immune response (Adachi et al, 2007).…”