Flori Pierre, Tardy Laëtitia, Jacquet Alain, Bellete Bahrie, Hafid Jamal, Raberin Hélène, Tran Manh Sung Roger
Laboratoire de Parasitologie-Mycologie, C.H.U. de Saint Etienne, Hôpital Nord, 42055, Saint-Etienne, cedex 2, France.
Parasitol Res. 2006 May;98(6):511-8. doi: 10.1007/s00436-005-0074-y. Epub 2006 Jan 17.
The efficacy of immunisation with Toxoplasma gondii recombinant protein (rSAG-1) was evaluated in the guinea pig model. For the infectious challenge, two strains, namely, strain C56 (10,000 tachyzoites) and strain 76K (100 cysts), were used to infect a group of 32 guinea pigs each. The circulating, cerebral and pulmonary parasite loads were determined with the real-time polymerase chain reaction (PCR) after immunisation. With the C56 strain, immunisation showed high activity with a reduction of greater than 1 log of the circulating and tissue parasite loads. Thus, there was a significantly lower circulating parasite load in the rSAG-1 + adjuvant group (0.5+/-1.5 Eq parasites/ml) as compared to that in the control group (67+/-110 Eq parasites/ml; p<0.05). In the same manner, the cerebral parasite load was much lower in the rSAG-1 + adjuvant group (10+/-20 Eq parasites/g) than that in the control group (339+/-291 Eq parasites/g; p<0.01). On the other hand, with the 76K strain, the effect of immunisation was much less and that only on the pulmonary parasite load [p(lung)<0.05]. This could be due to the use of different strains and stages of the parasite and/or the difference in the route of administration for challenge. The quantitative PCR technique used has shown a good correlation with animal inoculation, and when associated with the guinea pig model, it seems to be a useful and reproducible technique for future vaccine studies.
在豚鼠模型中评估了弓形虫重组蛋白（rSAG-1）免疫的效果。对于感染性攻击，使用两株菌株，即C56株（10,000个速殖子）和76K株（100个包囊）分别感染一组32只豚鼠。免疫后通过实时聚合酶链反应（PCR）测定循环、脑和肺中的寄生虫负荷。对于C56株，免疫显示出高活性，循环和组织寄生虫负荷减少超过1个对数。因此，与对照组（67±110 Eq寄生虫/ml）相比，rSAG-1+佐剂组的循环寄生虫负荷显著更低（0.5±1.5 Eq寄生虫/ml；p<0.05）。同样，rSAG-1+佐剂组的脑寄生虫负荷（10±20 Eq寄生虫/g）比对照组（339±291 Eq寄生虫/g；p<0.01）低得多。另一方面，对于76K株，免疫效果要小得多，且仅对肺寄生虫负荷有影响[p（肺）<0.05]。这可能是由于使用了不同的寄生虫菌株和阶段和/或攻击给药途径的差异。所使用的定量PCR技术已显示与动物接种有良好的相关性，并且与豚鼠模型结合时，它似乎是未来疫苗研究中一种有用且可重复的技术。
