Abstract
Extracellular matrix (ECM) composition and structural integrity is one of many factors that influence cellular differentiation. Fibronectin (FN) which is in many tissues the most abundant ECM protein forms a unique fibrillary network. FN homes several binding sites for sulfated glycosaminoglycans (sGAG), such as heparin (Hep), which was previously shown to influence FN conformation and protein binding. Synthetically sulfated hyaluronan derivatives (sHA) can serve as model molecules with a well characterized sulfation pattern to study sGAG-FN interaction. Here is shown that the low-sulfated sHA (sHA1) interacts with FN and influences fibril assembly. The interaction of FN fibrils with sHA1 and Hep, but not with non-sulfated HA was visualized by immunofluorescent co-staining. FRET analysis of FN confirmed the presence of more extended fibrils in human bone marrow stromal cells (hBMSC)-derived ECM in response to sHA1 and Hep. Although both sHA1 and Hep affected FN conformation, exclusively sHA1 increased FN protein level and led to thinner fibrils. Further, only sHA1 had a pro-osteogenic effect and enhanced the activity of tissue non-specific alkaline phosphatase. We hypothesize that the sHA1-triggered change in FN assembly influences the entire ECM network and could be the underlying mechanism for the pro-osteogenic effect of sHA1 on hBMSC.
Highlights
IntroductionFN has several binding domains for interaction partners in the extracellular matrix (ECM) like collagen I (dark blue) or growth factors (orange)
To investigate localization behavior of GAG derivatives, hBMSC were cultured on tissue culture polystyrene plates (TCPS) in Dulbecco’s Modified Eagle’s medium low glucose (DMEM) and were treated from day 1 until day 8 with ATTO565-labeled sHA1 and HA derivatives
We describe for the first time the impact of sulfated HA derivative on FN matrix assembly in hBMSC-derived extracellular matrix (ECM)
Summary
FN has several binding domains for interaction partners in the ECM like collagen I (dark blue) or growth factors (orange). FN is a binding partner of GAG, collagen I and other components of the ECM and facilitates network formation[26,27,28]. It homes three Hep binding regions located at FNI2-4, FNIII4-6 and FNIII12-14 (Fig. 1)[29,30]. We addressed the question whether the synthetically low-sulfated HA derivative sHA1 affects cellular FN matrix assembly and how this could be related to the pro-osteogenic effect of sHA1 on hBMSC12. The effect of sHA1, HA and Hep on osteogenic differentiation of hBMSC was evaluated determining the activity of tissue non-specific alkaline phosphatase (TNAP)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
