马来丝虫微丝蚴和感染期幼虫的低温保存及在宿主体内发育的观察

CRYOPRESERVATION OF MICROFILARIAE AND THIRD-STAGE LARVAE OF BRUGIA MALAYI AND SUBSEQUENT DEVELOPMENT IN THE HOSTS

应用6％二甲基亚砜(DMSO)、15％小牛血清的RPMI 1640作为低温保护液。微丝蚴(mf)和感染期幼虫(L_3)经不同时间的液氮内低温保存,其存活率均为96.2％,复苏后mf可在东乡伊蚊体内继续发育到L_3。低温保存321d的L_3经腹腔接种长爪沙鼠,71d后在接种107条L_3的鼠体内检获1条活的雌性成虫。结果还表明,mf或L_3于液氮内保存的时间长短与存活率无明显相关,其形态与未经冷冻的幼虫相同。

Methods are studied for the cryopreservation of microfilariae (mf) and third-stage larvae (L3) of periodic Brugia malayi. RPMI-1640 tissue culture medium containing 6% dimcthyl sulfoxide (DMSO) and 15% newborn calf serum were used as cryoprotectant.The larvae survived best when specimens were frozen at the rate of -0.5℃ to -1.0℃ per minute using the vapor phase of liquid nitrogen, when the temperature rea-ched - 70℃ to - 90℃ the specimens were placed directly into the liquid nitrogen (-196℃).After the thawing of the mf which had been stored for 6212 and 375 days in cryogen, 26.2% of the mf were shown to be viable and developed in Aedes togoi. It was also shown that the survival rate of L3 cryopreserved for 28-321 days was also S6.2% and that, wben 107 L3 frozen for 321 days were inoculated after being thawed into one jird, one live female adult was recovered at awopsy 71 days after inoculation, its morphology being the same as the unfrozen specimens.There was no correlation between the time of cryopreservation and the survival rate of the larvae.