Shapiro S Z, Naessens J, Liesegang B, Moloo S K, Magondu J
Acta Trop. 1984 Dec;41(4):313-23.
DNA content, at different stages in the life cycle of the hemoprotozoan parasite Trypanosoma brucei, has been analysed with a fluorescence activated cell sorter. It was observed that the long slender bloodstream form stage and procyclic culture forms (analogous to the tsetse fly midgut stage) are dividing cell populations with cells in G1, S, G2 and mitosis. Short stumpy bloodstream form and metacyclic fly salivary gland form populations are composed of non-dividing parasites stabilized in G1 or G0 of the cell cycle. Haploids, possible sexual forms, were not detected. In response to transfer to a culture system which mimics the fly midgut, short stumpy bloodstream form parasites were readily able to initiate DNA synthesis and differentiate into dividing procyclic culture forms. This supports the suggested role of the short stumpy form as a transitional stage between the mammalian host and the tsetse fly vector. Analysis of early and late bloodstream populations of another salivarian trypanosome, Trypanosoma vivax, revealed a transition from dividing to stationary cell population similar to that observed with T. brucei. A hitherto unrecognized morphological form of T. vivax, analogous to the T. brucei short stumpy form, was detected. It is suggested that the long slender to short stumpy morphological transformation, long known in T. brucei, reflects a physiological transition from dividing to nondividing parasite relevant to the life cycle of all the salivarian trypanosomes.
利用荧光激活细胞分选仪分析了血液原虫寄生虫布氏锥虫生命周期不同阶段的DNA含量。观察到，长细的血流形式阶段和前循环培养形式（类似于采采蝇中肠阶段）是处于细胞周期G1、S、G2期和有丝分裂期的分裂细胞群体。短粗的血流形式和循环后期采采蝇唾液腺形式群体由稳定在细胞周期G1期或G0期的非分裂寄生虫组成。未检测到单倍体，即可能的有性形式。将短粗的血流形式寄生虫转移到模拟采采蝇中肠的培养系统后，它们能够迅速启动DNA合成并分化为分裂的前循环培养形式。这支持了短粗形式作为哺乳动物宿主和采采蝇媒介之间过渡阶段的推测作用。对另一种涎源性锥虫——活泼锥虫的早期和晚期血流群体的分析显示，其从分裂细胞群体到静止细胞群体的转变与布氏锥虫类似。检测到一种以前未被认识的活泼锥虫形态形式，类似于布氏锥虫的短粗形式。有人提出，布氏锥虫中早已为人所知的从长细形态到短粗形态的转变，反映了与所有涎源性锥虫生命周期相关的从分裂寄生虫到非分裂寄生虫的生理转变。
