Dataset Information

Role of gamma interferon in chemokine expression in the ileum of mice and in a murine intestinal epithelial cell line after Cryptosporidium parvum infection.

ABSTRACT: Cryptosporidium parvum is a protozoan parasite that infects intestinal epithelial cells and induces inflammation of the intestine. To better understand the inflammatory process occurring during cryptosporidiosis, we investigated in this study the kinetics of chemokine expression in the mucosa of mice by quantitative reverse transcription-PCR. Our results demonstrate that among the chemokine mRNAs studied, gamma interferon (IFN-gamma)-inducible protein 10 (IP-10), monokine induced by IFN-gamma (MIG), i-TAC, lymphotactin, macrophage inflammatory protein 1 beta (MIP-1 beta), and RANTES mRNAs were strongly up-regulated in infected neonate mice, which correlated with the immunofluorescence staining results showing T-cell and macrophage infiltration in the mucosa. Our in vitro data showed that intestinal epithelial cells infected by C. parvum or stimulated by the proinflammatory cytokines (IFN-gamma, interleukin-1 beta, and tumor necrosis factor alpha) produce a pattern of chemokine secretion similar to that observed in vivo, suggesting that these cells may take part in the initial production of chemokines. In order to identify the chemokines responsible for the recruitment of the inflammatory cells leading to a protective immune response, we compared the patterns of chemokine expression in a healing neonate mouse model and a nonhealing IFN-gamma knockout (GKO) mouse model of cryptosporidiosis. In the absence of IFN-gamma, the chemokine response was altered for IP-10, MIG, i-TAC, RANTES, and MIP-1 beta mRNAs, while the three ELR C-X-C chemokine mRNAs studied (lipopolysaccharide-induced C-X-C chemokine, MIP-2 alpha, and KC mRNAs) were strongly overexpressed. These results are consistent with the neutrophil recruitment observed in the lamina propria of GKO mice at day 9 postinfection but are not consistent with the hypothesis that these cells play an important role in the resolution of the infection. On the contrary, the altered response of chemokines responsible for the recruitment of macrophages and T cells in GKO mice suggests that these two populations may be critical in the development of a protective immune response.

SUBMITTER: Lacroix-Lamande S

PROVIDER: S-EPMC127832 | biostudies-literature | 2002 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Role of gamma interferon in chemokine expression in the ileum of mice and in a murine intestinal epithelial cell line after Cryptosporidium parvum infection.

Lacroix-Lamandé Sonia S Mancassola Roselyne R Naciri Muriel M Laurent Fabrice F

Infection and immunity 20020401 4

Cryptosporidium parvum is a protozoan parasite that infects intestinal epithelial cells and induces inflammation of the intestine. To better understand the inflammatory process occurring during cryptosporidiosis, we investigated in this study the kinetics of chemokine expression in the mucosa of mice by quantitative reverse transcription-PCR. Our results demonstrate that among the chemokine mRNAs studied, gamma interferon (IFN-gamma)-inducible protein 10 (IP-10), monokine induced by IFN-gamma (M ...[more]

PMID: 11895975

Similar Datasets

Project description:The protozoan parasite Cryptosporidium sp. is a leading cause of diarrheal disease in those with compromised or underdeveloped immune systems, particularly infants and toddlers in resource-poor localities. As an enteric pathogen, Cryptosporidium sp. invades the apical surface of intestinal epithelial cells, where it resides in close proximity to metabolites in the intestinal lumen. However, the effect of gut metabolites on susceptibility to Cryptosporidium infection remains largely unstudied. Here, we first identified which gut metabolites are prevalent in neonatal mice when they are most susceptible to Cryptosporidium parvum infection and then tested the isolated effects of these metabolites on C. parvum invasion and growth in intestinal epithelial cells. Our findings demonstrate that medium or long-chain saturated fatty acids inhibit C. parvum growth, perhaps by negatively affecting the streamlined metabolism in C. parvum, which is unable to synthesize fatty acids. Conversely, long-chain unsaturated fatty acids enhanced C. parvum invasion, possibly by modulating membrane fluidity. Hence, gut metabolites, either from diet or produced by the microbiota, influence C. parvum growth in vitro and may also contribute to the early susceptibility to cryptosporidiosis seen in young animals.IMPORTANCE Cryptosporidium sp. occupies a unique intracellular niche that exposes the parasite to both host cell contents and the intestinal lumen, including metabolites from the diet and produced by the microbiota. Both dietary and microbial products change over the course of early development and could contribute to the changes seen in susceptibility to cryptosporidiosis in humans and mice. Consistent with this model, we show that the immature gut metabolome influenced the growth of Cryptosporidium parvum in vitro Interestingly, metabolites that significantly altered parasite growth were fatty acids, a class of molecules that Cryptosporidium sp. is unable to synthesize de novo The enhancing effects of polyunsaturated fatty acids and the inhibitory effects of saturated fatty acids presented in this study may provide a framework for future studies into this enteric parasite's interactions with exogenous fatty acids during the initial stages of infection.

Project description:To determine the specific transport system activities and expression of transporter genes responsible for uptake of L-arginine from the lumen of normal and Cryptosporidium parvum-infected neonatal porcine ileum and the influence of L-arginine catabolic pathways on L-arginine uptake.Intact sheets of ileal mucosa from control and C parvum-infected neonatal piglets were mounted in Ussing chambers and the uptake of 14C-L-arginine was determined under initial rate conditions and in the presence of transport system-selective inhibitors. Epithelial expression of L-arginine transporter genes was quantified by real-time reverse transcription polymerase chain reaction. L-Arginine catabolic enzyme expression was examined by immunoblotting epithelial lysates for arginase I and II. The role of intracellular catabolism in promoting the uptake of L-arginine was determined by pharmacological inhibition of nitric oxide synthase and arginase activities.C parvum-infected ileum transported L-arginine at rates equivalent to uninfected epithelium despite profound villous atrophy. This was attributed to enhanced uptake of L-arginine by individual epithelial cells in the infection. There were no differences in L-arginine transport system activities (y(+) and B(0, +)) or level of transporter gene expression (CAT-1, CAT-2A, and ATB(0, +)) between uninfected and C parvum-infected epithelial cells. However, infected epithelia had induced expression of the L-arginine hydrolytic enzyme arginase II and lower concentrations of L-arginine. Furthermore, transport of L-arginine by the infected epithelium was significantly inhibited by pharmacological blockade of arginase.Intracellular catabolism by arginase II, the induction of which has not been described previously for intestinal epithelium, facilitates uptake of L-arginine by infected epithelium using transport systems that do not differ from those of uninfected cells. Induction of arginase II may limit nitric oxide synthesis by competing with nitric oxide synthase for utilization of L-arginine or promote use of L-arginine for the synthesis of reparative polyamines.

Project description:Purpose: Transcriptome profiling of Crytosporidium parvum infected lung and small intestinal organoids was performed to access the response of epithelial cells upon parasitic infection and to do a temporal analysis of the transcriptome of the parasite inside the organoid lumen. We isolated RNA from infected human lung and small intestinal organoids at 24 and 72 hour post infection. Methods: Organoids were grown in expansion or differentiation media and microinjected with equal amounts of Cryptosporidium oocysts. Media-injected organoids were used as a control .Expanding SI organoids were microinjected at 5-6 days after seeding, differentiated SI organoids were injected at 5 days after inducing differentiation. Lung organoids were incubated for 2 weeks after seeding for microinjection. RNA was extracted from 1-2 matrigel drops containing organoids. RNA was converted to cDNA and libraries were prepared using the CelSeq2 method and sequenced. Samples were sequenced on Illumina NextSeq500 by using 75-bp paired-end sequencing. Methods: Paired-end reads from Illumina sequencing were aligned to the human transcriptome genome and C. parvum transcriptome genome (Iowa strain) by BWA. DeSeq (v1.18.0) was used for read normalization and differential expression analysis (p-value adjustment 0.05 by method Benjamini-Hochberg). Gene set enrichment analysis (GSEA) was performed using gene lists for type I interferon response and regulation against normalized RNA-seq reads of injected SI and lung organoids using GSEA software v3.0 beta2. Results: At 24 hr post-infection,GO (gene ontology)-term analysis revealed that a substantial number of genes related to ‘cytoskeleton’ and ‘cell mobility’ were up-regulated in lung organoids. This suggests that infection by the parasites and subsequent formation of the intracellular stages within 24 hrs might affects cytoskeleton structures of host cells. After 72 hrs, many genes associated with the type I interferon pathway increased dramatically in lung and intestinal organoids. Results: After 72 hrs, many genes associated with the type I interferon pathway increased dramatically in lung and intestinal organoids. Multiple C. parvum genes were differentially expressed with a large fold change between 24 and 72 hr post-injection.At 24 hr post-infection, most of the enriched genes represented ribosomal proteins and ribosomal RNA subunits in both intestinal organoids and lung organoids. By contrast, at 72 hr post-infection, multiple oocyst-wall protein genes were up-regulated, confirming that the parasites formed new oocysts within the organoids. Conclusions: RNA sequencing of injected organoids revealed host epithelial responses upon parasite infection in differentiated SI organoids as well as in lung organoids.Upregulation of genes associated with type I interferon immunity in both SI and lung organoids.

Dataset Information

Role of gamma interferon in chemokine expression in the ileum of mice and in a murine intestinal epithelial cell line after Cryptosporidium parvum infection.

Publications

Role of gamma interferon in chemokine expression in the ileum of mice and in a murine intestinal epithelial cell line after Cryptosporidium parvum infection.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets