四種非斑蚊媒介之人體血液及組織寄生鞭毛蟲:Leishmania donovani,Leishmania major,Leishmania tropica,及Trypanosoma cruzi,分別以液態的LMC培養液在27℃培養。另由斑蚊所分離的卵巢(ATO)細胞,以Hink's insect tissue culture(HITC)培養液在27℃培養。以血球計數器算細胞數目後調整濃度為每毫升含2×10^5個ATO細胞,以每槽一毫升的量,分別加入24槽細胞培養盤中,每槽中預置有適當大小的圓形蓋玻片一片,27℃隔夜培養後在各槽中分別加入1 毫升內含10^6上述各種鞭毛蟲的LMC培養液,再置於27℃培養,每24小時取出一批上有細胞的蓋玻片,風乾後,以絕對甲醇固定,經姬姆薩氏染液染色並水洗風乾後,倒封在載玻片上,以顯微鏡觀察結果。一天後受感染的ATO細胞於細胞質中出現1至2個無鞭型(amastigote)蟲體;二天後受L. tropica感染之細胞出現16個無鞭型蟲體,L. donovani出現4至8個,而其他則仍為1-2個;三天後,L. major感染出現32個無鞭型蟲體,而其他則為1至16個不等的無鞭型蟲體。除了錐鼻蟲的haemocytes之外,本篇為首次報告人體血液及組織寄生鞭毛蟲在體外培養無脊椎動物細胞內的分裂及發育。
The infectivities of four species of human parasitic hemoflagcllates to a mosquito ovary cell line, ATO, were studied in vitro. Promastigotes of Leishmania donovani, Leishmania major, and Leishmania tropica as well as epimastigotes of Trypanosoma cruzi were cultivated with a liquid metacyclic culture (LMC) medium at 27°C. Approximatelly 2 x 10^5 ATO cells in 1 ml Hink's insect tissue culture (HITC) medium were seeded onto a 13 mm diameter coverslip in each well of 24-well tissue culture plates. Promastigotes of leishmanias or epimastigotes of trypanosomes were washed and 106 organisms in I ml HITC medium were added into each well. The coverslips were removed from the well at 24-hr intervals for examination. The percentage of ATO cells infected and intracellular multiplication of the parasite were monitored by examining 3 repeats of 100 randomly selected cells. After 1 day of incubation, all infected ATO cells contained 1 to 2 amastigotes. Number of intracellular parasites increased gradually during the incubation. An average of approximately 5 to 7 amastigotes per infected cell was observed at the end of the third day. The highest percentage of infection was observed in L. donovani (2.3%), L. tropiea (5.7%), or L. major (12.3%) at 1, 2, or 3 days after incubation, respectively. Two days later, at most 16 amastigotes could be found in one L. tropica infected cells and 4 to 8 in L. donovani or L. major infected cells. After 3 days of incubation, 32 amastigotes were detected in one L. major infected cells. The differences in infectivity and intracellular multiplication in ATO cells among different parasite species needs further investigation.