ObjectiveTo investigate the inhibitory effect of the inhibition of antigen-presentation attenuators (iAPA)-based dendritic cells (DC) and cytotoxic T lymphocytes (CTL)-iAPA-DC/CTL on SMMC-7721 xenograft in nude mice. MethodsUsing the human hepatic carcinoma cell line SMMC-7721 on nude mice to establish a transplanted tumor model of human hepatocellular carcinoma (HCC).Twelve nude mice were divided into two groups randomly: normal saline control group (control group) and iAPA-DC/CTL group (n=6, each).After four times treatment with iAPA-DC/CTL (once a week), all mice were sacrificed.Tumor growth was calculated by measuring the long/short diameters and the tumor growth curve was delineated.The tumors were weighed and the tumor inhibition rate was calculated.In addition, the histopathological examination was conducted. ResultsThe SMMC-7721 xenograft model was successfully established in 85.71% (12/14) of all mice.The tumor volume was (3 661.48±322.59) mm3 and (2 725.36±252.65) mm3 in control group and iAPA-DC/CTL group, respectively.The tumor growth was significantly inhibited in iAPA-DC/CTL group (t=5.62, P < 0.05).The tumor weight was (1.97±0.21) g and (1.38±0.14) g in control group and iAPA-DC/CTL group, respectively.The tumor weight in iAPA-DC/CTL group was significantly reduced (t=5.73, P < 0.05), and the tumor inhibition rate was 29.95%.After immunohistochemical staining T lymphocyte counts was 0 cell/HPF and (54.24±4.31) cells/HPF in control group and iAPA-DC/CTL group, respectively.The number of T lymphocytes in iAPA-DC/CTL group was significantly increased (t=25.02, P < 0.05). ConclusioniAPA-DC/CTL could effectively inhibit the growth of subcutaneously implanted HCC.
ObjectiveTo investigate the effects of modification of acellular bovine pericardium with 1-ethyl-3-(3-dinethylami-nopropyl) carbodimide (EDC)/N-hydroxysuccininide (NHS) or genipin and find out the best crosslinking reagent. MethodsThe cellular components of the bovine pericardiums were removed. The effects of decellularization were tested by HE staining. The acellular bovine pericardiums were crosslinked with EDC/NHS (EDC/NHS group) or genipin (genipin group). The properties of the crosslinked acellular matrix were evaluated by scanning electron microscope (SEM), matrix thickness, crosslinking index, mechanical property, denaturation temperature, enzymatic degradation, and cytotoxicity test before and after the crosslinking. Acellular bovine pericardium (ABP group) or normal bovine pericardium (control group) were harvested as controls. ResultsSEM showed that collagen fibers were reticulated in bovine pericardial tissues after crosslinked by EDC/NHS or genipin, and relative aperture of the collagen fiber was from 10 to 20 μm. The thickness and denaturation temperature of the scaffolds were increased significantly after crosslinking with EDC/NHS or genipin (P<0.05), while there was no significant difference between EDC/NHS group and genipin group (P>0.05). The difference had no statistical significance in crosslinking index between EDC/NHS group and genipin group (t=0.205, P=0.218). The degradation rate in EDC/NHS group and genipin group was significantly lower than that in ABP group and control group (P<0.05). Elastic modulus and fracture stress in EDC/NHS group and genipin group were significantly lower than those in ABP group (P<0.05), but there was no significant difference among EDC/NHS group, genipin group, and control group (P>0.05). The break elongation in EDC/NHS group and genipin group were significantly increased than those in ABP group and control group (P<0.05). The difference had no statistical significance in stability and mechanical properties between EDC/NHS group and genipin group (P>0.05). Cytotoxicity of genipin crosslinked tissue (grade 1) were much lower than that of EDC/NHS (grade 2) at 5 days. ConclusionAcellular bovine pericardium crosslinked with genipin has better biocompatibility than EDC/NHS.