RESUMO
Objective To compare the growth of three different cancer cell lines on chick chorioallantoic membrane (CAM), to select the best transplanted cancer cell line for establishing a transplanted tumor model and to observe the biological characteristics.Methods The human lung cancer cell line A549, human tongue cancer cell line TCA8113 and human liver cancer cell line QGY7703 were respectively inoculated into CAM at the 7th day of age.The chick embryo survival rate, tumor survival rate, tumor formation rate and induced angiogenesis were detected and the growth characteristics of the transplanted tumor model were observed.Results Compared with the groups inoculated with A549 cells and QGY7703 cells, the tumor formation rate of TCA8113 cells was the highest (P < 0.05), to be the best cancer cell line for transplanted tumor.The optimal inoculated number of cells was 8.0×106/chick embryo, the optimal growth period of the tumor was 4~8 d, and the best experiment time was 7 d after inoculation.Conclusion The TCA-CAM transplanted tumor model of tongue squamous cell cancer is successfully established for further study of the biological characteristics and mechanisms of tumor growth, angiogenesis, invasion and metastasis, and provide a good experimental animal model for anti-tumor drug screening.
RESUMO
cDNAs of the HA genes of subtype H5N1 AIV were fused to form a single open reading frame, designated H5HA-H7HA. The H5HA-H7HA cDNA and chicken Interleukin-18 (IL18) were inserted into the fowlpox virus (FPV) expression vector pUTA-16-LacZ to produce pUTAL-H5-H7-IL18. cDNA of H5N1 AIV HA was inserted into the FPV expression vector pUTA2 to create the recombinant expression plasmid pUTA2-H5. Plasmids were then co-transected into CEF cells. The two recombinant fowlpox viruses (rFPV) were produced by three cycles with the BrdU and verified by RT-PCR, IFA and Western blotting. One-day-old specific pathogen free (SPF) chickens and 7-day-old commercial Leghorn egg-laying chickens were inoculated with 10(6) PFU recombinant or parental fowlpox vaccine viruses by wing-web puncture. Hemagglutination inhibition (HI) antibody titer and nonspecific cellular immunity level were assessed after 1-3 weeks post-immunization. We found that all rFPV-vaccinated groups produced HI-specific antibodies, and the level of cellular immunity induced by the rFPV-H5-H7-IL18 strain was significantly higher than that induced by rFPV-H5HA. At 3 weeks post-inoculation, immunized SPF and Leghorn chickens were challenged with H5N1 HP AIV. The rFPV-H5-H7-IL18 vaccine strains were able to induce complete (10/10) protection, while the rFPV-H5HA vaccine strain induced (9/10) protection. Cloacal swabbing samples were collected from immunized leghorn chickens during the first week post-challenge; no shedding was found in the rFPV-H5-H7-IL18 vaccinated group. The rFPV-H5-H7-IL18 vaccinated group displayed significantly increased weight gain relative to the rFPV-H5HA group. This study reports a significant step in the further development of new AIV vaccines.
