Tufts Cummings School of Veterinary Medicine, Division of Infectious Diseases, North Grafton, MA 01536, USA.
Infect Immun. 2010 Mar;78(3):1040-8. doi: 10.1128/IAI.01009-09. Epub 2009 Dec 28.
To study the transcriptional response of mammalian cells to infection with the intracellular apicomplexan parasite Cryptosporidium parvum, infected and uninfected cells were recovered from C. parvum-infected cell monolayers. This approach, which contrasts with a more conventional experimental design that compares infected to uninfected cell monolayers, enabled the identification of functional categories of genes that are differentially transcribed as a direct consequence of the presence of intracellular parasites. Among several categories of upregulated genes, glycoprotein metabolism was significantly overrepresented. To investigate whether these transcriptional changes affected the composition of the surface of infected cells, cells were probed with fluorescently labeled lectins. Among a panel of seven lectins, soybean agglutinin, which recognizes N-acetyl-d-galactosamine, generated the largest difference in fluorescence between infected and uninfected cells. The origin of the fluorescent signal emitted by infected cells was further investigated and attributed to the overexpression of glycoprotein on the surface of infected cells, as well as the presence of glycoprotein located in the proximity of intracellular parasites.
为了研究哺乳动物细胞对细胞内顶复门寄生虫微小隐孢子虫感染的转录反应，从微小隐孢子虫感染的细胞单层中回收感染和未感染的细胞。与更传统的实验设计相比，这种方法将感染细胞与未感染细胞单层进行比较，能够鉴定出因细胞内寄生虫的存在而差异转录的功能类别基因。在几个上调基因类别中，糖蛋白代谢显著过表达。为了研究这些转录变化是否影响感染细胞表面的组成，用荧光标记的凝集素探测细胞。在一组七种凝集素中，大豆凝集素识别 N-乙酰-d-半乳糖胺，在感染细胞和未感染细胞之间产生最大的荧光差异。进一步研究了感染细胞发出的荧光信号的来源，并归因于感染细胞表面糖蛋白的过度表达，以及位于细胞内寄生虫附近的糖蛋白的存在。
