Mesenchymal stem cells associated with porous chitosan–gelatin scaffold: A potential strategy for alveolar bone regeneration

Abstract

Tissue engineering has emerged as a novel treatment for replacement of lost bone tissue. This study evaluated the effects of a chitosan-gelatin scaffold seeded with bone marrow mesenchymal stem cells (BMMSCs) in the healing process of tooth sockets in rats. BMMSCs isolated from transgenic rats expressing enhanced green fluorescent protein (eGFP) were expanded and seeded on a chitosan-gelatin scaffold. These constructs were cultured for three days and characterized by scanning electronic microscopy (SEM) and energy dispersion spectroscopy (EDS). Receptor rats received the implant in the left sockets, after upper first-molar extraction. Right alveoli served as control. Animals were sacrificed at days 5, 21, and 35 post-graft for examination. Morphometry demonstrated increased bone mineralization after 21 and 35 days in transplanted sockets. Migration, differentiation, and fate of eGFP-labeled BMMSCs were monitored by immunohistochemistry. Tartrate-resistant acid phosphatase staining (TRAP) was carried out at 21 days, to identify the involvement of osteoclastic cells in the scaffold resorption. The biomaterial was resorbed by TRAP-negative giant cells in a typical foreign body reaction. Immunohistochemical findings showed that BMMSCs contributed to bone, epithelial, and vascular repair. Together, results indicate that BMMSCs loaded in the chitosan-gelatin scaffold is a strategy for tissue development in bone engineering.

Polyhydroxybutyrate-co-hydroxyvalerate structures loaded with adipose stem cells promote skin healing with reduced scarring

“…Keywords: 27 Wound healing 28 Scar 29 Tissue engineering 30 Myofibroblasts 31 Paracrine signaling 32 3 3 a b s t r a c t 34 Currently available skin substitutes are still associated with a range of problems including poor engraft- 35 ment resulting from deficient vascularization, and excessive scar formation, among others. Trying to 36 overcome these issues, this work proposes the combination of poly(3-hydroxybutyrate-co-hydroxyvaler- 37 ate) (PHBV) structures with adipose-derived stem cells (ASCs) to offer biomechanical and biochemical 38 signaling cues necessary to improve wound healing in a full-thickness model.…”

Versatility of Chitosan-Based Biomaterials and Their Use as Scaffolds for Tissue Regeneration

“…In 83.33% of the studies in which scaffolds were compared, either with or without these components, the results showed a better regenerative performance with the presence of cells and/or growth factors. In other studies, there was no difference in results, neither with nor without bioactive factors [29, 56, 80], or there was no comparison between them [46, 62, 81]. Therefore, it cannot be asserted, from the results presented, that chitosan possesses per se activity that induces tissue regeneration, as some authors suggest [7, 10, 16, 22, 25].…”

“…In fact, some studies have clearly shown that the association of CS with collagen [42, 44, 68], silk fibroin [73], and HA [45, 57, 58] was capable of promoting greater tissue regeneration than pure CS, as in these studies pure or combined CS scaffolds were implanted, making it possible to establish a comparison between them. However, in the vast majority of studies evaluating CS combined with other biomaterials, the favorable results obtained cannot be attributed to the associations, as pure CS was neither evaluated nor used as a control [8, 30, 32, 41, 46, 48, 49, 53, 54, 62, 63, 67, 71, 76, 77, 80, 81, 83, 86, 88]. …”

“…Statistical power is the probability that a statistical test will indicate a significant difference when there truly is one. In this review, some studies used small samples for their in vivo assays, with n = 3  [32, 46–48, 61, 65, 68, 81], n = 2 [27, 56, 69], and even n = 1  [72]. It is important to point out that the value of n considered in this study is always the number of animals used for each treatment condition.…”

Hydrogel of polysaccharide of sugarcane molasses as carrier of bone morphogenetic protein in the reconstruction of critical bone defects in rats

“…Many carriers have been tested experimentally, using scaffolds composed of chitosan-gelatin blends 7 or bioactive glass showing biointegration and remodeling of tissues with features that allow for future applications 10,11 . This study assessed by CT imaging and histology, the ability to osteo-promotion of the association of biopolymer gel as carrier of bone morphogenetic protein and lyophilized bone grafts in the formation of a barrier compared to collagen membrane of bovine origin in the treatment of critical defects in rats calvarium in periods of 90 and 180 days after surgery.…”