Effects of laminin on hard tissue formation by bone marrow cells <i>in vivo</i> and <i>in vitro</i>

Abstract

The effect of laminin on hard tissue formation using rat bone marrow cells was assessed. Rat bone marrow cells were obtained from femora of 6-week-old male Fischer 344 rats. In this in vivo examination, porous cylindrical hydroxyapatite scaffolds with a hollow center were immersed in 100 µg/ml laminin solution and air-dried. Rat bone marrow cells in 200 µl culture medium at 1 × 10 6 cells/ml were seeded in the scaffolds. The scaffolds were implanted into the dorsal subcutis of 7-week-old male Fischer 344 rats for 6 weeks. The scaffolds were then removed and examined histologically. For in vitro examinations, 1 × 10 5 rat bone marrow cells in 2 ml culture medium were then cultured with the addition of dexamethasone and laminin. Rat bone marrow cells were also cultured in laminin-coated culture plates. In vitro examinations showed the effectiveness of laminin for hard tissue formation from the results of biochemical and immunochemical analysis. From the in vivo examination, laminin coating of the scaffolds induced hard tissue in the pores with the cells. It is concluded that laminin is useful for bone formation, as in an in vitro culture study using bone marrow cells, in hydroxyapatite scaffolds in vivo.

Calcified Nodule Formation <i>in Vitro</i> Using Rat Mandibular Incisor Pulp Cells

“…In this study, calcified nodules were formed by cells from dental pulp. The appearance of the nodules was different from those formed by rBMCs in our previous reports [21][22][23]. Microscopically, the calcified nodules formed by rDPCs had lower levels of Ca 2+ deposition than the nodules by rBMCs.…”

“…Based on our in vitro preliminary experiments, the period for dental pulp cell culture until calcified nodule formation from the primary culture may be long. In the previous in vivo and in vitro studies by Yoshikawa et al [5] [21][22][23], bone marrow cells from the femur of rats were used to examination hard tissue formation as a substitute for cells obtained from dental pulp. The proliferation of stem cells in dental pulp cells was not evaluated and osteogenic potential of bone marrow cells was not compared with hard tissue forming ability by dental pulp-derived cells in this study.…”

“…In general, 10 days of primary culture followed by 10 -14 days of subculture is considered to be required to obtain calcified nodules in vitro using rBMCs from the femur. In our previous in vitro studies using rat bone marrow cells, the period required to form calcified nodules was 1 week for primary culture and 2 weeks of subculture [22]. In this in vitro study, calcified nodule formation by rDPCs was examined at 33 days.…”

Laminin‐111 Inhibits Bovine Fertilization but Improves Embryonic Development in vitro, and Receptor Integrin‐β1 is Involved in Sperm–Oocyte Binding

“…Laminins can also improve the differentiation of pluripotent cells, such as promoting bone formation by co‐action with Dex and β ‐GP (Yoshikawa et al. ), modulating the epithelial‐to‐mesenchymal transition in embryonic stem cells by regulating the expression of E‐cadherin, MMP2 and MMP9 (Horejs et al. ) and acting as a potent differentiation inducer of IPCs from UC‐MSCs via the pdx1 and Nqn3 signalling pathways (Qu et al.…”

“…) as well as the formation of organization (Yoshikawa et al. ) and the regulation of cell signalling (Imanishi et al. ; Yun et al.…”