RESUMO
Hepatectomy is an effective surgical method for the treatment of liver diseases, but intraoperative bleeding and postoperative liver function recovery are still key issues. This study aims to develop a composite hydrogel dressing with excellent hemostatic properties, biocompatibility, and ability to promote liver cell regeneration. The modified gelatin matrix (GelMA, 10%) was mixed with equal volumes of sodium alginate-dopamine (Alg-DA) at concentrations of 0.5%, 1%, and 2%. Then a cross-linking agent (0.1%) was added to prepare different composite hydrogels under UV light, named GelMA/Alg-DA-0.5, GelMA/Alg-DA-1 and GelMA/Alg-DA-2, respectively. All the prepared hydrogel has a porous structure with a porosity greater than 65%, and could be stabilized in a gel state after being cross-linked by ultraviolet light. Physicochemical characterization showed that the elastic modulus, water absorption, adhesion, and compressibility of the composite hydrogels were improved with increasing Alg-DA content. Furthermore, the prepared hydrogel exhibits in vitro degradability, excellent biocompatibility, and good hemostatic function. Among all tested groups, the group of GelMA/Alg-DA-1 hydrogel performed the best. To further enhance its application potential in the field of liver regeneration, adipose-derived mesenchymal stem cell exosomes (AD-MSC-Exo) were loaded into GelMA/Alg-DA-1 hydrogel. Under the same conditions, GelMA/Alg-DA-1/Exo promoted cell proliferation and migration more effectively than hydrogels without extracellular vesicles. In conclusion, the prepared GelMA/Alg-DA-1 composite hydrogel loaded with AD-MSC-Exo has great application potential in liver wound hemostasis and liver regeneration.
RESUMO
BACKGROUND: Treatment for de novo or recurrent tumors of liver transplantation (LT) recipients is challenging and immune checkpoint inhibitor (ICI) is recently well developed and could be a potentially effective option for this population. There remains limited evidence on the safety and efficacy of ICI therapy in LT recipients. METHODS: A systematic literature search was conducted on PubMed database through April 1, 2022, to identify publications reporting ICI treatment for malignant tumors in LT recipients. We summarized the allograft rejection, mortality, and tumor response of ICI treatment. RESULTS: 24 articles with 41 LT recipients were identified. The age of LT recipients ranged from 14 to 78, 76.2% were male, 56.1% had recurrent HCC, and 87.8% received anti-PD-1 therapy. Allograft rejection occurred in 31.7% of patients, death was reported in 46.3% and 6 cases died secondary to allograft rejection. Progressive disease rate of this population was 48.8% and 10 patients responded to immunotherapy. Half of recipients with positive PD-L1 staining (4/8) experienced allograft rejection. CONCLUSIONS: ICI therapy has potential therapeutic value on malignant tumors for LT recipients, accompanied by a high rate of allograft rejection and mortality. PD-L1 expression, type of ICI, and immunosuppression agent should be taken into consideration before initiation of immunotherapy. Further studies are needed to optimize this anticancer treatment approach in these patients.
