ABSTRACT
Objective: To observe the effect of thermosensitive hydroxybutyl chitosan (HBC) hydrogel in the prevention of intrauterine adhesion in New Zealand white rabbits. Methods: Eighteen female New Zealand rabbits were randomly divided into 3 groups, i. e., normal control group, model group and HBC group. Normal control group underwent sham operation. The models of intrauterine adhesion were constructed by both mechanical damage and infection in model group and HBC group. In HBC group, 2 mL 1.5% thermosensitive HBC hydrogel was injected into the uterine cavity immediately after injury. Two rabbits were killed in each group 1 week, 2 weeks and 4 weeks after operation, respectively. The bilateral uterine tissues were collected. The endometrial morphology and quantity of glands were observed by hematoxylin-eosin staining. The area of fibrosis in endometrium was measured by Masson staining. Results: One week after operation, compared with normal control group, the columnar epithelial cells of endometrium gradually disappeared and the ratio of endometrial fibrosis area increased significantly in the other two groups. The number of glands also decreased. After 2 weeks, intrauterine adhesion was observed in model group, and the ratio of endometrial fibrosis area continued increasing, and the number of glands decreased further. However, in HBC group, there was no residual hydrogel in the uterine cavity, and the ratio of endometrial fibrosis area decreased and the number of glands increased. After 4 weeks, there was a recovery of columnar epithelium cells, the ratio of endometrial fibrosis area, and the number of glands in HBC group, which returned to the normal level. Conclusion: Thermosensitive HBC hydrogel can effectively prevent intrauterine adhesion in New Zealand white rabbits.
ABSTRACT
Tissue engineering (TE) has become an alternative for auricular reconstruction based on the combination of cells, molecular signals and biomaterials. Scaffolds are biomaterials that provide structural support for cell attachment and subsequent tissue development. Ideally, a scaffold should have characteristics such as biocompatibility and bioactivity to adequate support cell functions. Our purpose was to evaluate biocompatibility of microtic auricular chondrocytes seeded onto a chitosan-polyvinyl alcohol-epichlorohydrin (CS-PVA-ECH) hydrogel to propose this material as a scaffold for tissue engineering application. After being cultured onto CS-PVA-ECH hydrogels, auricular chondrocytes viability was up to 81%. SEM analysis showed cell attachment and extracellular matrix formation that was confirmed by IF detection of type II collagen and elastin, the main constituents of elastic cartilage. Expression of elastic cartilage molecular markers during in vitro expansion and during culture onto hydrogels allowed confirming auricular chondrocyte phenotype. In vivo assay of tissue formation revealed generation of neotissues with similar physical characteristics and protein composition to those found in elastic cartilage. According to our results, biocompatibility of the CS-PVA-ECH hydrogel makes it a suitable scaffold for tissue engineering application aimed to elastic cartilage regeneration.
La ingeniería de tejidos (TE) es una alternativa para la reconstrucción auricular basada en la combinación de células, señales moleculares y biomateriales. Los andamios fabricados con biomateriales brindan un soporte estructural que favorece la adhesión cellular y el desarrollo del tejido. Un andamio debe poseer características como biocompatibilidad y bioactividad para soportar adecuadamente funciones celulares. Nuestro objetivo fue evaluar la biocompatibilidad de condrocitos auriculares de microtia cultivados sobre un hidrogel a base de quitosano-alcohol polivinílico-epiclorhidrina (CS-PVA-ECH) y proponerlo como andamio con aplicaciones en ingeniería de tejidos. La viabilidad de los condrocitos auriculares es superior al 81% después de ser cultivados sobre el hidrogel. El análisis por SEM reveló la unión celular y formación de matriz extracellular sobre el hidrogel; confirmada mediante detección por IF de colágena tipo II y elastina. La expresión de marcadores moleculares durante la expansión in vitro y el cultivo sobre los hidrogeles confirmaron el fenotipo condral. El ensayo de formación de tejido in vivo demostró la generación de neotejidos con características físicas y composición similar al cartílago elástico. Nuestros resultados indican que la biocompatibilidad del hidrogel de CS-PVA-ECH lo hace un andamio adecuado para aplicaciones en ingeniería de tejidos enfocadas a regeneración de cartílago elástico.