Gillin F D, Gault M J, Hofmann A F, Gurantz D, Sauch J F
Infect Immun. 1986 Sep;53(3):641-5. doi: 10.1128/iai.53.3.641-645.1986.
Giardia lamblia has been grown in vitro only in media containing serum or serum fractions. How this pathogen can grow in the human small intestinal lumen without serum is not known. We found that samples of human hepatic or gall bladder bile maintained G. lamblia survival for 24 to 48 h in medium without serum but did not support growth. By contrast, an artificial biliary lipid dispersion containing six bile salts, phosphatidylcholine (PC), and cholesterol, in the ratios characteristic of human bile, supported parasite growth in medium without serum or serum fractions. To define the requirements, we showed that 1-palmitoyl-2-linoleoyl-PC or 1-palmitoyl-2-oleoyl-PC (which predominate in human bile) satisfied the requirement for PC. Moreover, either glycocholate or glycodeoxycholate could be substituted for the bile salt mixture. The finding that biliary lipids can support serum-free growth of G. lamblia may help explain why this parasite colonizes the upper small intestine.
蓝氏贾第鞭毛虫仅在含有血清或血清成分的培养基中才能在体外培养。目前尚不清楚这种病原体如何在无血清的人类小肠腔中生长。我们发现，人肝胆汁或胆囊胆汁样本可使蓝氏贾第鞭毛虫在无血清培养基中存活24至48小时，但无法支持其生长。相比之下，一种含有六种胆汁盐、磷脂酰胆碱（PC）和胆固醇的人工胆汁脂质分散体，其比例与人胆汁的特征比例相同，可在无血清或血清成分的培养基中支持寄生虫生长。为了确定其生长所需条件，我们发现1-棕榈酰-2-亚油酰-PC或1-棕榈酰-2-油酰-PC（在人胆汁中占主导）满足了对PC的需求。此外，甘氨胆酸盐或甘氨脱氧胆酸盐均可替代胆汁盐混合物。胆汁脂质可支持蓝氏贾第鞭毛虫无血清生长这一发现，或许有助于解释该寄生虫为何能定殖于上段小肠。
