Representational difference analysis identifies specific genes in the interaction of Giardia duodenalis with the murine intestinal epithelial cell line, IEC-6

Giardia duodenalis Cathepsin B Proteases Degrade Intestinal Epithelial Interleukin-8 and Attenuate Interleukin-8-Induced Neutrophil Chemotaxis

“…Parasitic cysteine proteases have been shown to prevent activation of proinflammatory transcription factors (88), degrade host effector molecules (89), promote specific host immune responses (90,91), and cleave host chemokines (46,87). Prior to this study, reports had described roles for a G. duodenalis catB protease in trophozoite encystation and excystation (41), but the role of these proteases in disease pathogenesis and host immunity has remained largely speculative (43,92,93). The results presented herein demonstrated for the first time that catB proteases secreted by G. duodenalis trophozoites might be associated with the attenuation of aspects of their host's proinflammatory immune response.…”

“…The G. duodenalis genome contains genes for numerous cathepsin cysteine proteases, the majority of which have no described function (41,42). However, several G. duodenalis cathepsin proteases are upregulated upon exposure to IECs (43). While some parasites may use cathepsin cysteine proteases to evade or modulate their host's immune responses (reviewed in references 44 and 45), previous research has demonstrated that Entamoeba histolytica cysteine protease 2 (EhCP2) cleaves CXCL8 into a more potent isoform that enhances PMN chemotaxis (46).…”

Identification of differentially expressed genes related to metabolic syndrome induced with high-fat diet in E3 rats

“…At present, methods such as representational difference analysis technology (RDA), [10][11][12] serial analysis of gene expression, cDNA microarray technology, 13,14 and subtractive hybridization technology (SSH), have been widely used to identify the genes differentially expressed in diseased tissues. cDNA microarray, with the advantages of speediness and possibility to assay thousands of genes, is commonly used to analyze known transcripts.…”

Gene expression changes during Giardia–host cell interactions in serum-free medium

“…As controls, we performed SAGE on parasites grown alone in each TYI-S-33 (Giardia growth medium with serum) and M199 medium (interaction medium). When Giardia interacted with IECs in M199, 46 genes were significantly up-regulated and 45 downregulated as compared to Giardia alone in TYI-S-33 (Table S1) studies using parasites co-incubated with differentiated Caco-2 cells in complete DMEM and compared to parasites grown in TYI-S-33 or parasites interacting with the rat intestinal epithelial cell line IEC-6 [6,11]. Thus, most genes are expressed to the same degree in M199 serum-free medium and in TYI-S-33 or complete DMEM, showing that that M199 medium is suitable for studies of Giardia-host cell interactions.…”

“…Genes encoding nitroreductase, peroxiredoxin, FixW-like proteins and thioredoxin reductase were up-regulated after 2.5 h (Table S1 and Fig. S2) and their protein products have been shown to protect against oxidative stress in Giardia and other parasitic protozoa [11][12][13][14]. Glucose-6-phosphate 1-dehydrogenase and 6-phosphogluconate dehydrogenase, key enzymes in the pentose phosphate pathway, show more than 10-fold up-regulation after 2.5 h of interaction (Table S1).…”