关键词: 疟原虫子孢子, 梯度离心法, 低速离心, 感染性, 肝细胞, 发育率, 红外期, 寄生虫学, 感染率, 大鼠

Abstract: P. yoelii sporozoites(Sp) in Anopheles stephensi were first isolated with low-speed centrifugation and the Sp suspension was subsequantly purified with the density gradient centrifugation. The recovery rates of Sp by the latter method is about 50-75% of that by the former, but few debris could be found in the Sp suspension and the infectivity of the Sp was not weakened as compared with the Sp obtained by low-speed method. Sp would retain partial infectivity, when its suspension was maintained ia medium 199 at 4℃ for 48 hrs. When rats and mice were infected with these Sp, patho-logical changes of hepatocytes such as cloudy swelling or fatty degeneration, which had been evidenced to be induced by mosquito tissues, would be absent or present in th slightest degree.