scholarly journals Human Primary Intestinal Epithelial Cells as an ImprovedIn VitroModel for Cryptosporidium parvum Infection

2013 ◽  
Vol 81 (6) ◽  
pp. 1996-2001 ◽  
Author(s):  
Alejandro Castellanos-Gonzalez ◽  
Miguel M. Cabada ◽  
Joan Nichols ◽  
Guillermo Gomez ◽  
A. Clinton White

ABSTRACTThe study of human intestinal pathogens has been limited by the lack of methods for the long-term culture of primary human intestinal epithelial cells (PECs). The development of infection models with PECs would allow a better understanding of host-parasite interactions. The objective of this study was to develop a novel method for prolongedin vitrocultivation of PECs that can be used to studyCryptosporidiuminfection. We isolated intact crypts from human intestines removed during weight loss surgery. The fragments of intestinal layers were cultivated with culture medium supplemented with growth factors and antiapoptotic molecules. After 7 days, the PECs formed self-regenerating cell clusters, forming villi that resemble intestinal epithelium. The PECs proliferated and remained viable for at least 60 days. The cells expressed markers for intestinal stem cells, epithelial cells, and mature enterocytes. The PECs were infected withCryptosporidium. In contrast to older models in which parasite numbers decay, the burden of parasites increased for >120 h. In summary, we describe here a novel method for the cultivation of self-regenerating human epithelial cells from small intestinal crypts, which contain both intestinal stem cells and mature villus cells. We present data that suggest these cells supportCryptosporidiumbetter than existing cell lines. PECs should provide an improved tool for studying host-parasite interactions involvingCryptosporidiumand other intestinal pathogens.

2019 ◽  
Vol 20 (7) ◽  
pp. 690-695
Author(s):  
Xi Chen ◽  
Zehong Yang ◽  
Huiling Hu ◽  
Wentao Duan ◽  
Aiping Wang ◽  
...  

Weaning is a stressful event associated with gastrointestinal disorders and increased disease susceptibility. Many studies have reported the changes that happened in the gut of various mammals such as pigs and rats after weaning. These findings suggest that the development of intestinal tract mainly is affected at the time of weaning through interfering in the differentiation and proliferation of intestinal stem cells. Weaning stress stimulates the rapid differentiation and proliferation of intestinal stem cells in order to adjust to changes caused by weaning, which are mainly manifested as deeper crypt depth and decreased intestine villus height. However, the accelerated cellular process may lead to an increase in the proportion of immature intestinal epithelial cells and goblet cells, which affect intestinal permeability and reduce the gut-barrier function against toxins and pathogens. This review briefly describes the effects coforticotrophin-releasing factor (CRF), epidermal growth factor (EGF) and polyamines on the differentiation and proliferation of intestinal stem cells after weaning and discusses its possible underlying regulatory mechanisms. Firstly, weaning stress activates CRF to binds its receptors, which induces proinflammatory responses and promote rapid differentiation and proliferation of intestinal stem cells to a larger fraction of immature intestinal epithelial cells and goblet cells. Secondly, the lack of EGF after weaning inhibits the expression of goblet cell maturation factors and makes it difficult for goblet cells and intestinal epithelial cells to mature. Finally, diet and endogenous synthesis lead to excessive polyamines in the intestine, which promote the proliferation of intestinal stem cells by regulating the expression of human antigen R (HuR) and other related genes at the time of weaning.


2014 ◽  
Vol 454 (4) ◽  
pp. 493-499 ◽  
Author(s):  
Nobukatsu Horita ◽  
Kiichiro Tsuchiya ◽  
Ryohei Hayashi ◽  
Keita Fukushima ◽  
Shuji Hibiya ◽  
...  

2019 ◽  
Vol 116 (5) ◽  
pp. 1704-1713 ◽  
Author(s):  
Yukiko Hiramatsu ◽  
Akihisa Fukuda ◽  
Satoshi Ogawa ◽  
Norihiro Goto ◽  
Kozo Ikuta ◽  
...  

Inactivating mutations of Arid1a, a subunit of the Switch/sucrose nonfermentable chromatin remodeling complex, have been reported in multiple human cancers. Intestinal deletion of Arid1a has been reported to induce colorectal cancer in mice; however, its functional role in intestinal homeostasis remains unclear. We investigated the functional role of Arid1a in intestinal homeostasis in mice. We found that intestinal deletion of Arid1a results in loss of intestinal stem cells (ISCs), decreased Paneth and goblet cells, disorganized crypt-villous structures, and increased apoptosis in adult mice. Spheroids did not develop from intestinal epithelial cells deficient for Arid1a. Lineage-tracing experiments revealed that Arid1a deletion in Lgr5+ ISCs leads to impaired self-renewal of Lgr5+ ISCs but does not perturb intestinal homeostasis. The Wnt signaling pathway, including Wnt agonists, receptors, and target genes, was strikingly down-regulated in Arid1a-deficient intestines. We found that Arid1a directly binds to the Sox9 promoter to support its expression. Remarkably, overexpression of Sox9 in intestinal epithelial cells abrogated the above phenotypes, although Sox9 overexpression in intestinal epithelial cells did not restore the expression levels of Wnt agonist and receptor genes. Furthermore, Sox9 overexpression permitted development of spheroids from Arid1a-deficient intestinal epithelial cells. In addition, deletion of Arid1a concomitant with Sox9 overexpression in Lgr5+ ISCs restores self-renewal in Arid1a-deleted Lgr5+ ISCs. These results indicate that Arid1a is indispensable for the maintenance of ISCs and intestinal homeostasis in mice. Mechanistically, this is mainly mediated by Sox9. Our data provide insights into the molecular mechanisms underlying maintenance of ISCs and intestinal homeostasis.


2019 ◽  
Vol 93 (18) ◽  
Author(s):  
Mia Madel Alfajaro ◽  
Ji-Yun Kim ◽  
Laure Barbé ◽  
Eun-Hyo Cho ◽  
Jun-Gyu Park ◽  
...  

ABSTRACTGroup A rotaviruses, an important cause of severe diarrhea in children and young animals, initiate infection via interactions of the VP8* domain of the VP4 spike protein with cell surface sialic acids (SAs) or histo-blood group antigens (HBGAs). Although the bovine G6P[5] WC3 strain is an important animal pathogen and is also used in the bovine-human reassortant RotaTeq vaccine, the receptor(s) for the VP8* domain of WC3 and its reassortant strains have not yet been identified. In the present study, HBGA- and saliva-binding assays showed that both G6P[5] WC3 and mono-reassortant G4P[5] strains recognized the αGal HBGA. The infectivity of both P[5]-bearing strains was significantly reduced in αGal-free MA-104 cells by pretreatment with a broadly specific neuraminidase or by coincubation with the α2,6-linked SA-specificSambucus nigralectin, but not by the α2,3-linked specific sialidase or byMaackia amurensislectin. Free NeuAc and the αGal trisaccharide also prevented the infectivity of both strains. This indicated that both P[5]-bearing strains utilize α2,6-linked SA as a ligand on MA104 cells. However, the two strains replicated in differentiated bovine small intestinal enteroids and in their human counterparts that lack α2,6-linked SA or αGal HBGA, suggesting that additional or alternative receptors such as integrins, hsp70, and tight-junction proteins bound directly to the VP5* domain can be used by the P[5]-bearing strains to initiate the infection of human cells. In addition, these data also suggested that P[5]-bearing strains have potential for cross-species transmission.IMPORTANCEGroup A rotaviruses initiate infection through the binding of the VP8* domain of the VP4 protein to sialic acids (SAs) or histo-blood group antigens (HBGAs). Although the bovine G6P[5] WC3 strain is an important animal pathogen and is used as the backbone in the bovine-human reassortant RotaTeq vaccine, the receptor(s) for their P[5] VP8* domain has remained elusive. Using a variety of approaches, we demonstrated that the WC3 and bovine-human mono-reassortant G4P[5] vaccine strains recognize both α2,6-linked SA and αGal HBGA as ligands. Neither ligand is expressed on human small intestinal epithelial cells, explaining the absence of natural human infection by P[5]-bearing strains. However, we observed that the P[5]-bearing WC3 and G4P[5] RotaTeq vaccine strains could still infect human intestinal epithelial cells. Thus, the four P[5] RotaTeq vaccine strains potentially binding to additional alternative receptors may be efficient and effective in providing protection against severe rotavirus disease in human.


2015 ◽  
Vol 83 (8) ◽  
pp. 3213-3223 ◽  
Author(s):  
Wei Zhang ◽  
Jiang-Yuan Du ◽  
Qing Yu ◽  
Jun-O Jin

Interleukin-7 (IL-7) engages multiple mechanisms to overcome chronic viral infections, but the role of IL-7 in bacterial infections, especially enteric bacterial infections, remains unclear. Here we characterized the previously unexplored role of IL-7 in the innate immune response to the attaching and effacing bacteriumCitrobacter rodentium.C. rodentiuminfection induced IL-7 production from intestinal epithelial cells (IECs). IL-7 production from IECs in response toC. rodentiumwas dependent on gamma interferon (IFN-γ)-producing NK1.1+cells and IL-12. Treatment with anti-IL-7Rα antibody duringC. rodentiuminfection resulted in a higher bacterial burden, enhanced intestinal damage, and greater weight loss and mortality than observed with the control IgG treatment. IEC-produced IL-7 was only essential for protective immunity againstC. rodentiumduring the first 6 days after infection. An impaired bacterial clearance upon IL-7Rα blockade was associated with a significant decrease in macrophage accumulation and activation in the colon. Moreover,C. rodentium-induced expansion and activation of intestinal CD4+lymphoid tissue inducer (LTi) cells was completely abrogated by IL-7Rα blockade. Collectively, these data demonstrate that IL-7 is produced by IECs in response toC. rodentiuminfection and plays a critical role in the protective immunity against this intestinal attaching and effacing bacterium.


2018 ◽  
Vol 84 (16) ◽  
Author(s):  
Jai W. Mehat ◽  
Simon F. Park ◽  
Arnoud H. M. van Vliet ◽  
Roberto M. La Ragione

ABSTRACTCampylobacter jejuniis recognized as an important causative agent of bacterial gastroenteritis in the developed world. Despite the identification of several factors contributing to infection, characterization of the virulence strategies employed byC. jejuniremains a significant challenge. Bacterial autotransporter proteins are a major class of secretory proteins in Gram-negative bacteria, and notably, many autotransporter proteins contribute to bacterial virulence. The aim of this study was to characterize theC. jejuni81116 C8J_1278 gene (capC), predicted to encode an autotransporter protein, and examine the contribution of this factor to virulence ofC. jejuni. The predicted CapC protein has a number of features that are consistent with autotransporters, including the N-terminal signal sequence and the C-terminal β-barrel domain and was determined to localize to the outer membrane. Inactivation of thecapCgene inC. jejuni81116 andC. jejuniM1 resulted in reduced insecticidal activity inGalleria mellonellalarvae. Furthermore,C. jejuni capCmutants displayed significantly reduced adherence to and invasion of nonpolarized, partially differentiated Caco-2 and T84 intestinal epithelial cells. Gentamicin treatment showed that the reduced invasion of thecapCmutant is primarily caused by reduced adherence to intestinal epithelial cells, not by reduced invasion capability.C. jejuni capCmutants caused reduced interleukin 8 (IL-8) secretion from intestinal epithelial cells and elicited a significantly diminished immune reaction inGallerialarvae, indicating that CapC functions as an immunogen. In conclusion, CapC is a new virulence determinant ofC. jejunithat contributes to the integral infection process of adhesion to human intestinal epithelial cells.IMPORTANCECampylobacter jejuniis a major causative agent of human gastroenteritis, making this zoonotic pathogen of significant importance to human and veterinary public health worldwide. The mechanisms by whichC. jejuniinteracts with intestinal epithelial cells and causes disease are still poorly understood due, in part, to the heterogeneity ofC. jejuniinfection biology. Given the importance ofC. jejunito public health, the need to characterize novel and existing virulence mechanisms is apparent. The significance of our research is in demonstrating the role of CapC, a novel virulence factor inC. jejunithat contributes to adhesion and invasion of the intestinal epithelium, thereby in part, addressing the dearth of knowledge concerning the factors involved inCampylobacterpathogenesis and the variation observed in the severity of human infection.


2007 ◽  
Vol 70 (1) ◽  
pp. 125-134 ◽  
Author(s):  
MARÍA G. VIZOSO PINTO ◽  
TOBIAS SCHUSTER ◽  
KARLIS BRIVIBA ◽  
BERNHARD WATZL ◽  
WILHELM H. HOLZAPFEL ◽  
...  

Five Lactobacillus plantarum strains and two Lactobacillus johnsonii strains, stemming either from African traditionally fermented milk products or children's feces, were investigated for probiotic properties in vitro. The relationship between the hydrophobic-hydrophilic cell surface and adhesion ability to HT29 intestinal epithelial cells was investigated, and results indicated that especially the L. johnsonii strains, which exhibited both hydrophobic and hydrophilic surface characteristics, adhered well to HT29 cells. Four L. plantarum and two L. johnsonii strains showed high adherence to HT29 cells, generally higher than that of the probiotic control strain Lactobacillus rhamnosus GG. Most strains with high adhesion ability also showed high autoaggregation ability. The two L. johnsonii strains coaggregated well with the intestinal pathogens Listeria monocytogenes Scott A, Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Salmonella enterica serovar Typhimurium ATCC 14028. The L. plantarum BFE 1685 and L. johnsonii 6128 strains furthermore inhibited the adhesion of at least two of these intestinal pathogens in coculture with HT29 cells in a strain-dependent way. These two potential probiotic strains also significantly increased interleukin-8 (IL-8) chemokine production by HT29 cells, although modulation of other cytokines, such as IL-1, IL-6, IL-10, monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor alpha (TNF-α), and transforming growth factor β (TGF-β), did not occur. Altogether, our results suggested that L. plantarum BFE 1685 and L. johnsonii BFE 6128 showed good adherence, coaggregated with pathogens, and stimulated chemokine production of intestinal epithelial cells, traits that may be considered promising for their development as probiotic strains.


Cells ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1895 ◽  
Author(s):  
Sepideh Fallah ◽  
Jean-François Beaulieu

The human intestine is covered by epithelium, which is continuously replaced by new cells provided by stem cells located at the bottom of the glands. The maintenance of intestinal stem cells is supported by a niche which is composed of several signaling proteins including the Hippo pathway effectors YAP1/TAZ. The role of YAP1/TAZ in cell proliferation and regeneration is well documented but their involvement on the differentiation of intestinal epithelial cells is unclear. In the present study, the role of YAP1/TAZ on the differentiation of intestinal epithelial cells was investigated using the HT29 cell line, the only multipotent intestinal cell line available, with a combination of knockdown approaches. The expression of intestinal differentiation cell markers was tested by qPCR, Western blot, indirect immunofluorescence and electron microscopy analyses. The results show that TAZ is not expressed while the abolition of YAP1 expression led to a sharp increase in goblet and absorptive cell differentiation and reduction of some stem cell markers. Further studies using double knockdown experiments revealed that most of these effects resulting from YAP1 abolition are mediated by CDX2, a key intestinal cell transcription factor. In conclusion, our results indicate that YAP1/TAZ negatively regulate the differentiation of intestinal epithelial cells through the inhibition of CDX2 expression.


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