抗氯喹恶性疟原虫体外连续培养及其抗性程度的变化

CONTINUOUS CULTURE OF CHLOROQUINE-RESISTANT PLASMODIUM FALCIPARUM IN VITRO AND VARIATIONS OF ITS RESISTANT DEGREES TO ANTIMALARIALS

目的 建立抗氯喹恶性疟原虫体外连续培养株 ,观察其对氯喹和喹哌的抗性变化。 方法 按 Trager等常规恶性疟原虫体外培养方法和 Reckmann等分别进行体外连续培养和药效测试。 结果 所解冻培养的 3虫株 ,在培养初期疟原虫生长细弱 ,且能产生配子体 ,并以低配子体率维持一定时间 ,随着配子体消失 ,疟原虫无性体健壮 ,繁殖良好 ;对药敏测定 ,3株疟原虫对氯喹皆具高程度抗性 (分别为 32、6 4和 32 pmol/ # ) ;对喹哌也具抗性 (分别为 6 4、6 4和 32pmol/ # ) ,但连续培养一定时间后 ,对氯喹抗性程度逐渐下降 ,最后皆转变为敏感 (分别为第 170、110和第 80 d)。而对喹哌抗性则无变化。 结论 3株抗氯喹恶性疟原虫对氯喹抗性不稳定 ,可能与原抗性程度不高和易逆有关。

Objective To establish Hainan strain of chloroquine-resistant Plasmodium falciparum continuously cultured in vitro and observe its resistant changes to chloroquine and piperaquine. Methods To carry out the continuous culture in vitro and drug test according to Tragers method of common P. falciparum culture in vitro and Recmanns drug testing method respectively. Results The three parasite strains cultured after thawed grew slowly and weak during the early stage of culture and gametocytes were produced .The development of the gometocytes maintained at a low development rate for a certain number of days. The asexual forms became robust and multiplied well along with the disappearance of gametocytes. In the drug tests, all of three parasite strains showed high grade of resistance to chloroquine (at the concentration of 32?64 and 32 pmol/well, respectively), the resistance to piperaquine was also noticed (at the concentration of 64, 64 and 32 pmol/well, respectively). While the resistance of the parasites to chloroquine was gradually reduced after continuously cultured in a certain days and finally became sensitive (170?110 and 80 days after culture, respectively). No variations of resistance to piperaquine was observed in the tests. Conclusion The resistant unstability of the three strains of chloroquine-resistant P. falciparum to chloroquine might be due to the low resistant degree before test and the reversible resistance.