转染B7基因的U14疫苗对小鼠宫颈癌的防治作用研究

目的 :探讨转染B7基因的U14疫苗能否在中国 6 15系小鼠体内诱导抗宫颈癌主动免疫应答。方法 :将小鼠B7 1基因导入 6 15系小鼠宫颈癌U14细胞 ,建立高效表达B7 1的U14细胞株 (B7+U14 )及其细胞疫苗。 (1)用B7+U14疫苗免疫 6 15系小鼠 ,观察U14皮下移植成瘤情况 ;(2 )用B7+U14疫苗治疗 6 15系荷瘤小鼠。设立对照组 ,观察各组小鼠的成瘤情况、生存期 ;(3)体外实验检测经B7+U14和U14疫苗免疫小鼠T细胞杀伤肿瘤的活性。结果 :(1)B7+U14疫苗免疫可有效地预防野生型U14细胞移植瘤的产生 (比较肿瘤大小、生存期 :P <0 .0 1) ;(2 )B7+U14疫苗能治愈部分荷瘤小鼠 ,其效果受荷瘤大小的限制 ,肿瘤直径 >3mm时 ,B7+U14疫苗治疗无效 (P <0 .0 5 ) ;(3)经B7+U14和U 14疫苗免疫小鼠T细胞 ,其不同效靶比杀伤肿瘤效率前者明显高于后者 (P <0 .0 0 1)。结论 :转染B7基因的U14细胞疫苗能诱导机体产生有效的抗宫颈癌主动免疫应答。应用转染B7基因的肿瘤细胞疫苗可能成为临床术后治疗宫颈癌的有效辅助方法。     

共刺激分子B7基因诱导小鼠抗宫颈癌

目的探讨共刺激分子B7基因能否在体内诱导小鼠抗宫颈癌主动免疫应答。方法将B7基因转染小鼠宫颈癌细胞株即U14,建立高表达B7的U14细胞株即B7+U14。随后分4组进行体内实验(1)实验A组将B7+U14（1×107个细胞）接种于同系615小鼠的右侧背部皮下（n=6）。(2)实验B组用B7+U14（1×106个细胞）皮下注射免疫615小鼠,7d后将U14（1×107个细胞）接种于免疫后的小鼠背部皮下（n=6）。(3)对照A组在615小鼠右侧背部皮下接种U14（1×107个细胞）,其余条件同实验A组。(4)对照B组用U14（1×106个细胞）免疫615小鼠,其余条件同实验B组。观察4组小鼠的成瘤情况、生存时间;体外分别检测经B7+U14和U14免疫后的小鼠（n=4×2）T淋巴细胞对肿瘤细胞的杀伤作用。结果(1)小鼠皮下接种B7+U14后,体内的致瘤能力明显降低（P<0.01）。(2)用B7+U14免疫后再皮下接种U14可有效预防移植瘤产生（P<0.01）。(3)体外检测经B7+U14和U14免疫后的小鼠T淋巴细胞杀伤肿瘤细胞作用,前者明显高于后者（P<0.01）。结论B7基因转染小鼠宫颈癌细胞株U14能诱导机体有效的抗肿瘤主动免疫应答,提示应用B7基因转染法可能成为临床治疗宫颈癌的有效方法。     

共刺激分子B7基因诱导小鼠抗子宫颈癌主动免疫的研究

目的　探讨共刺激分子B7基因能否在体内诱导小鼠抗宫颈癌主动免疫应答。方法　将B7基因转染小鼠宫颈癌细胞株即U14,建立高表达B7的U14细胞株即B7 U14。随后分 4组进行体内实验 :(1)实验A组 :将B7 U14(1× 10 7个细胞 )接种于同系 6 15小鼠的右侧背部皮下 (n =6 )。(2 )实验B组 :用B7 U14(1× 10 6个细胞 )皮下注射免疫 6 15小鼠 ,7d后将U14(1× 10 7个细胞 )接种于免疫后的小鼠背部皮下 (n =6 )。 (3)对照A组 :在 6 15小鼠右侧背部皮下接种U14(1× 10 7个细胞 ) ,其余条件同实验A组。 (4 )对照B组 :用U14(1× 10 6个细胞 )免疫 6 15小鼠 ,其余条件同实验B组。观察 4组小鼠的成瘤情况、生存时间 ;体外分别检测经B7 U14和U14免疫后的小鼠 (n =4× 2 )T淋巴细胞对肿瘤细胞的杀伤作用。结果　 (1)小鼠皮下接种B7 U14后 ,体内的致瘤能力明显降低 (P<0 0 1)。(2 )用B7 U14免疫后再皮下接种U14可有效预防移植瘤产生 (P <0 0 1)。(3)体外检测经B7 U14和U14免疫后的小鼠T淋巴细胞杀伤肿瘤细胞作用 ,前者明显高于后者 (P <0 0 1)。结论　B7基因转染小鼠宫颈癌细胞株U14能诱导机体有效的抗肿瘤主动免疫应答 ,提示应用B7基因转染法可能成为临床治疗宫颈癌的有效方法     

Therapeutic antitumor response to cervical cancer in mice immunized with U14 v accines transfected with costimulatory B7 gene

Objective To investigate the effect of U14 vaccine transfected with the B7 gene in inducin g antitumor immune response to murine cervical carcinoma in Chinese 615-strain mice.Methods A recombinant retroviral plasmid vector expressing mouse B7-1 gene (pLNSX-mB7) was transfected into 615-strain mouse cervical carcinoma cell line No. 14 (U1 4) by electroporation to set up a highly-expressed mB7-1 U14 cell clonal strai n (B7(+)U14). In vivo experiments: (1) B7(+)U14 vaccine was primed to protect t he 615-strain mice against U14 re-challenge. (2) B7(+)U14 vaccine was injecte d into tumor-bearing mice with different tumor sizes. Lifetimes and tumor s izes were recorded. In vitro cytotoxicity assay: Mice were immunized with B 7(+)U14 or U14 vaccine and 2 weeks later, spleen cells of those mice were cultur ed for 2 days. The cytotoxicity of these cells against U14 was detected by 5-d iphenyl tetrazolium bromide assay.Results We obtained several B7-1 high expression clonal U14 lines. In vivo experiment, we did not find tumor growing in 3 of the 6 mice primed by B7(+)U14 vaccine during their entire life after re-challenge with U14. The other 3 mice develo ped tumors and their average survival time was longer than that of the control g roup (P&lt;0.01). All 6 mice grew tumors in the control group. When the transplanted tumors became palpable, the mice were randomly divided into 3 group s to be injected with B7(+)U14 vaccine. It was effective for tumor-bearing mic e only when the tumor diameters were &lt;3 mm. When the diameters were ≥3 mm, it was not efficacious to inject B7(+)U14 vaccine (P&lt;0.05). In vitro cytotoxicity assay, cytotoxic T lymphocytes induced by B7(+)U14 vaccine h ad a high er cytotoxicity against U14 than that induced by U14 vaccine (F=310.8, P &lt;0.001).Conclusions Vaccines of cervical cancer cells transfected with the costimulatory molecule B7 gene can induce antitumor immune protection in host mice against U14 re-challe nge. This treatment may cure part of the tumor-bearing mice but be restricted by tumor size. The results suggest that transfecting the B7 gene into cervical cancer as a cell vaccine may be an efficient supplementary method to treat cervi cal cancer after operation.