鼠疫组分疫苗免疫后小鼠血清抗体滴度检测与豚鼠效力观察

Detection of mouse serum antibody titer and observation of the efficiency of protecting guinea pigs against plague after immunization with plague component vaccines

目的根据对小鼠血清抗体滴度检测和对豚鼠的保护力观察，评估鼠疫组分疫苗的免疫效果。方法通过氢氧化铝佐剂吸附15μgF1、15μgrV、15μgF1＋15μgrV抗原，分别制成鼠疫单组分疫苗和双组分疫苗。采用2剂（0、2周）皮下接种途径，分别免疫NIH小鼠和豚鼠。以皮上划痕人用鼠疫活疫苗1剂免疫作为对照。免疫6周后，采用间接ELISA法检测小鼠血清IgG滴度，采用t检验作组间比较。与此同时，使用强毒鼠疫杆菌141株对豚鼠进行皮下攻击，以观察疫苗效力。结果小鼠血清抗体检测结果表明，鼠疫组分疫苗组血清F1抗体或／和rV抗体滴度均高于鼠疫活疫苗组，差异有统计学意义（t=3．041、3．472、15．958、16．264，P值均〈0．01）。豚鼠攻击试验结果显示，F1＋rV组的存活率可达到90％（9／10），而F1组和rV组分别为50％（5／10）和20％（2／10）。结论鼠疫F1＋rV双组分疫苗是有效的抗鼠疫疫苗，而单组分F1或rV鼠疫疫苗不能有效防御鼠疫杆菌攻击。

Objective To evaluate efficiency of plague component vaccines by detection of mouse serum antibody titer and observation of protecting guinea pigs against virulent Yersinia pestis challenge. Methods The plague component vaccines were prepared by admixing 15 μg F1 antigen, 15 μg rV antigen and 15 μg F1 ＋ 15 μg rV antigen with aluminum hydroxide adjuvant, respectively. NIH mice and guinea pigs were immunized with 2 doses of plague component vaccines subcutaneously at a schedule of 0 and 2 weeks. The animals were immunized with one dose of live attenuated plague vaccine for percutaneous scarification as a control group. Serum anti-F1 and anti-rV IgG titers in mice were determined by indirect ELISA 6 weeks after immunization, and guinea pigs were subcutaneously challenged with virulent Y. pestis strain 141 to observe the efficiency of the plague component vaccines, t test was adopted in the comparison between the groups. Results The results of antibody determination showed that anti-F1 IgG or/and anti-rV IgG levels in three plague compo- nent vaccine groups were much higher than those in live attenuated plague vaccine group, and these were statisti- cally significant differences between plague component vaccine groups and live vaccine group（ t = 3. 041,3. 472, 15.958,16. 264,P 〈0. 01 ）. The results of challenge test in guinea pigs showed that the survival rate in F1 ＋ rV vaccine group was 90% （9/10） , and those in F1 vaccine group and rV vaccine group were 50 % （5/10） and 20% （2/10）, respectively. Conclusions The plague F1 ＋ rV vaccine is effective for preventing plague, and F1 vaccine or rV vaccine is unable to provide effective protection against virulent Y. pestis challenge.