Wiser M F, Giraldo L E, Schmitt-Wrede H P, Wunderlich F
Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana 70112, USA.
Exp Parasitol. 1997 Jan;85(1):43-54. doi: 10.1006/expr.1996.4126.
The immunogenicity of a 93-kDa Plasmodium chabaudi protein that contains glutamate-rich tandem repeats was investigated in this study. Immunoblotting with various monoclonal antibodies indicates that this 93-kDa protein is equivalent to a potential P. chabaudi RESA analogue. However, the sequence of the P. chabaudi protein does not exhibit any significant homology to Pf155/RESA. Antibodies against the 93-kDa protein appear early during P. chabaudi infection and reach high titers. The highest antibody titers are found when the parasitemia is descending, suggesting that this protein may play some role in immunity. Immunization of mice with the recombinant protein also results in high antibody titers, indicating that the protein is quite immunogenic. However, mice immunized with recombinant protein and challenged with P. chabaudi do not exhibit a delayed appearance of parasitemia, a reduced parasitemia, or a shortened duration of parasitemia. Glutamate-rich P. falciparum proteins such as Pf155/RESA, are being considered as vaccine candidates. The studies with P. chabaudi suggest that interpretation of serological data using glutamate-rich proteins should proceed with caution. The glutamate-rich repeats, although highly immunogenic, may not be important in host immunity against malaria. However, antibodies that appear late in the P. chabaudi infection do appear to play a role in anti-malarial immunity.
本研究调查了一种含有富含谷氨酸串联重复序列的93 kDa查巴迪疟原虫蛋白的免疫原性。用各种单克隆抗体进行免疫印迹分析表明，这种93 kDa蛋白等同于一种潜在的查巴迪疟原虫RESA类似物。然而，查巴迪疟原虫蛋白的序列与Pf155/RESA没有任何显著的同源性。针对93 kDa蛋白的抗体在查巴迪疟原虫感染早期出现，并达到高滴度。当疟原虫血症下降时发现抗体滴度最高，这表明该蛋白可能在免疫中发挥某种作用。用重组蛋白免疫小鼠也会导致高抗体滴度，表明该蛋白具有很强的免疫原性。然而，用重组蛋白免疫并经查巴迪疟原虫攻击的小鼠并未出现疟原虫血症延迟出现、疟原虫血症降低或疟原虫血症持续时间缩短的情况。富含谷氨酸的恶性疟原虫蛋白，如Pf155/RESA，正被考虑作为候选疫苗。对查巴迪疟原虫的研究表明，使用富含谷氨酸的蛋白解释血清学数据时应谨慎。富含谷氨酸的重复序列虽然具有高度免疫原性，但可能在宿主抗疟疾免疫中并不重要。然而，在查巴迪疟原虫感染后期出现的抗体似乎确实在抗疟疾免疫中发挥作用。
