scholarly journals Role of the glycocalyx in regulating access of microparticles to apical plasma membranes of intestinal epithelial cells: implications for microbial attachment and oral vaccine targeting.

1996 ◽  
Vol 184 (3) ◽  
pp. 1045-1059 ◽  
Author(s):  
A Frey ◽  
K T Giannasca ◽  
R Weltzin ◽  
P J Giannasca ◽  
H Reggio ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Plasma Membranes ◽  
Intestinal Epithelial Cells ◽  
Oral Vaccine ◽  
M Cells ◽  
Intestinal Epithelial ◽  
M Cell ◽  
Antigen Uptake ◽  
Apical Membranes

Transepithelial transport of antigens and pathogens across the epithelial barrier by M cells may be a prerequisite for induction of mucosal immunity in the intestine. Efficient transport of antigens and pathogens requires adherence to M cell apical surfaces. Coupling of antigen-containing particles to the pentameric binding subunit of cholera toxin (CTB) has been proposed as a means for increasing antigen uptake because the CTB receptor, ganglioside GM1, is a glycolipid present in apical membranes of all intestinal epithelial cells. To test the accessibility of enterocyte and M cell membrane glycolipids to ligands in the size ranges of viruses, bacteria, and particulate mucosal vaccines, we analyzed binding of CTB probes of different sizes to rabbit Peyer's patch epithelium. Soluble CTB-fluorescein isothiocyanate (diameter 6.4 nm) bound to apical membranes of all epithelial cells. CTB coupled to 14 nm colloidal gold (final diameter, 28.8 nm) failed to adhere to enterocytes but did adhere to M cells. CTB-coated, fluorescent microparticles (final diameter, 1.13 microns) failed to adhere to enterocytes or M cells in vivo or to well-differentiated Caco-2 intestinal epithelial cells in vitro. However, these particles bound specifically to GM1 on BALB/c 3T3 fibroblasts in vitro and to undifferentiated Caco-2 cells that lacked brush borders and glycocalyx. Measurements of glycocalyx thickness by electron microscopy suggested that a relatively thin (20 nm) glycocalyx was sufficient to prevent access of 1-micron microparticles to glycolipid receptors. Thus, the barrier function of the intestinal epithelial cell glycocalyx may be important in limiting microbial adherence to membrane glycolipids, and in CTB-mediated targeting of vaccines to M cells and the mucosal immune system.

scholarly journals M CELLS ARE THE IMPORTANT POST IN THE INITIATION OF IMMUNE RESPONSE IN INTESTINE

2018 ◽  
Vol 8 (3) ◽  
pp. 263-272
Author(s):  
A. S. Bykov ◽  
A. V. Karaulov ◽  
D. A. Tsomartova ◽  
N. L. Kartashkina ◽  
V. L. Goriachkina ◽  
...  
Keyword(s):  
Immune System ◽  
Epithelial Cells ◽  
Immune Responses ◽  
Targeted Delivery ◽  
Oral Vaccine ◽  
Critical Event ◽  
M Cells ◽  
M Cell ◽  
Antigen Uptake ◽  
And Function

Microfold cells (M cells) are specialized intestinal epithelial cells that initiate mucosal immune responses. These unique phagocytic epithelial cells are specialized for the transfer of a broad range of particulate antigens and microorganisms across the follicle-associated epithelium (FAE) into the gut-associated lymphoid tissue (GALT) by a process termed transcytosis. The molecular basis of antigen uptake by M cells has been gradually identified in the last decade. Active sampling of intestinal antigen initiates regulated immune responses that ensure intestinal homeostasis. The delivery of luminal substances across the intestinal epithelium to the immune system is a critical event in immune surveillance resulting in tolerance to dietary antigens and immunity to pathogens (e.g., bacteria, viruses, and parasites) and their toxins. Several specialized mechanisms transport luminal antigen across the gut epithelium. Discovery of M cell-specific receptors are of great interest, which could act as molecular tags for targeted delivery oral vaccine to M cells. Recent studies demonstrated that M cells utilize several receptors to recognize and transport specific luminal antigens. Vaccination through the mucosal immune system can induce effective systemic immune responses simultaneously with mucosal immunity. How this process is regulated is largely unknown. This review aims to show a new understanding of the factors that influence the development and function of M cells; to show the molecules expressed on M cells which appear to be used as immunosurveillance receptors to sample pathogenic microorganisms in the gut; to note how certain pathogens appear to exploit M cells to inject the host; and, finally, how this knowledge is used to specifically "target" antigens to M cells to attempt to improve the efficacy of mucosal vaccines. Recently, substantial progress has been made in our understanding of the factors that influence the development and function of M cells.

scholarly journals Protective Effects of Lactoferrin against SARS-CoV-2 Infection In Vitro

Nutrients ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 328 ◽  
Author(s):  
Claudio Salaris ◽  
Melania Scarpa ◽  
Marina Elli ◽  
Alice Bertolini ◽  
Simone Guglielmetti ◽  
...  
Keyword(s):  
Immune Response ◽  
Epithelial Cells ◽  
Intestinal Epithelial Cells ◽  
Plaque Assay ◽  
Immune Response Gene ◽  
Intestinal Epithelial ◽  
Antiviral Immune Response ◽  
Qrt Pcr ◽  
Anti Inflammatory

SARS-CoV-2 is a newly emerging virus that currently lacks curative treatments. Lactoferrin (LF) is a naturally occurring non-toxic glycoprotein with broad-spectrum antiviral, immunomodulatory and anti-inflammatory effects. In this study, we assessed the potential of LF in the prevention of SARS-CoV-2 infection in vitro. Antiviral immune response gene expression was analyzed by qRT-PCR in uninfected Caco-2 intestinal epithelial cells treated with LF. An infection assay for SARS-CoV-2 was performed in Caco-2 cells treated or not with LF. SARS-CoV-2 titer was determined by qRT-PCR, plaque assay and immunostaining. Inflammatory and anti-inflammatory cytokine production was determined by qRT-PCR. LF significantly induced the expression of IFNA1, IFNB1, TLR3, TLR7, IRF3, IRF7 and MAVS genes. Furthermore, LF partially inhibited SARS-CoV-2 infection and replication in Caco-2 intestinal epithelial cells. Our in vitro data support LF as an immune modulator of the antiviral immune response with moderate effects against SARS-CoV-2 infection.

The effect of berberine in vitro on tight junctions in human Caco-2 intestinal epithelial cells

Fitoterapia ◽  
2009 ◽  
Vol 80 (4) ◽  
pp. 241-248 ◽  
Author(s):  
Lili Gu ◽  
Ning Li ◽  
Qiurong Li ◽  
Qiang Zhang ◽  
Chengyang Wang ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Tight Junctions ◽  
Intestinal Epithelial Cells ◽  
Intestinal Epithelial

scholarly journals A σ28-Regulated Nonflagella Gene Contributes to Virulence of Campylobacter jejuni 81-176

2006 ◽  
Vol 74 (1) ◽  
pp. 769-772 ◽  
Author(s):  
Scarlett Goon ◽  
Cheryl P. Ewing ◽  
Maria Lorenzo ◽  
Dawn Pattarini ◽  
Gary Majam ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Campylobacter Jejuni ◽  
Diarrheal Disease ◽  
Intestinal Epithelial Cells ◽  
Disease Model ◽  
Intestinal Epithelial ◽  
Model Expression

ABSTRACT A Campylobacter jejuni 81-176 mutant in Cj0977 was fully motile but reduced >3 logs compared to the parent in invasion of intestinal epithelial cells in vitro. The mutant was also attenuated in a ferret diarrheal disease model. Expression of Cj0977 protein was dependent on a minimal flagella structure.

Proteomic response of inflammatory stimulated intestinal epithelial cells to in vitro digested plums and cabbages rich in carotenoids and polyphenols

2016 ◽  
Vol 7 (10) ◽  
pp. 4388-4399 ◽  
Author(s):  
Anouk Kaulmann ◽  
Sébastien Planchon ◽  
Jenny Renaut ◽  
Yves-Jacques Schneider ◽  
Lucien Hoffmann ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Inflammatory Bowel Diseases ◽  
Intestinal Epithelial Cells ◽  
Intestinal Cells ◽  
Intestinal Epithelial ◽  
Bowel Diseases ◽  
Inflammatory Bowel ◽  
Proteomic Response

Proteomic response of intestinal cells as a model of inflammatory bowel diseases to digested plum and cabbage rich in polyphenols and carotenoids.

Progastrin1–80stimulates growth of intestinal epithelial cells in vitro via high-affinity binding sites

2003 ◽  
Vol 284 (2) ◽  
pp. G328-G339 ◽  
Author(s):  
P. Singh ◽  
X. Lu ◽  
S. Cobb ◽  
B. T. Miller ◽  
N. Tarasova ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Binding Sites ◽  
Intestinal Epithelial Cells ◽  
Full Length ◽  
Intestinal Epithelial ◽  
Growth Effects ◽  
High Affinity ◽  
Significant Difference

Proliferation and carcinogenesis of the large intestinal epithelial cells (IEC) cells is significantly increased in transgenic mice that overexpress the precursor progastrin (PG) peptide. It is not known if the in vivo growth effects of PG on IEC cells are mediated directly or indirectly. Full-length recombinant human PG (rhPG1–80) was generated to examine possible direct effects of PG on IEC cells. Surprisingly, rhPG (0.1–1.0 nM) was more effective than the completely processed gastrin 17 (G17) peptide as a growth factor. Even though IEC cells did not express CCK1and CCK2receptors (-R), fluorescently labeled G17 and Gly-extended G17 (G-Gly) were specifically bound to the cells, suggesting the presence of binding proteins other than CCK1-R and CCK2-R on IEC cells. High-affinity ( Kd= 0.5–1.0 nM) binding sites for125I-rhPG were discovered on IEC cells that demonstrated relative binding affinity for gastrin-like peptides in the order PG ≥ COOH-terminally extended G17 ≥ G-Gly > G17 > *CCK-8 (* significant difference; P< 0.05). In conclusion, our studies demonstrate for the first time direct growth effects of the full-length precursor peptide on IEC cells in vitro that are apparently mediated by the high-affinity PG binding sites that were discovered on these cells.

A thermal injury-induced circulating factor(s) compromises intestinal cell morphology, proliferation, and migration

1999 ◽  
Vol 277 (1) ◽  
pp. G175-G182 ◽  
Author(s):  
Maryam Varedi ◽  
George H. Greeley ◽  
David N. Herndon ◽  
Ella W. Englander
Keyword(s):  
Epithelial Cells ◽  
Thermal Injury ◽  
Intestinal Epithelial Cells ◽  
Intestinal Cell ◽  
Intestinal Epithelial ◽  
Rat Serum ◽  
In Vitro Effects ◽  
Mucosal Morphology ◽  
And Migration

The effects of a 60% body surface area thermal injury in rats on the morphology and proliferation of the epithelium of the small intestine and the in vitro effects of serum collected from scalded rats on intestinal epithelial cells were investigated. Scald injury caused significant reductions in duodenal villus width and crypt dimensions, villus enterocytes changed in shape from columnar to cuboidal, and the number of goblet cells decreased. The proportion of bromodeoxyuridine-labeled S phase cells in crypts was also diminished. In vitro, incubation of intestinal epithelial cells (IEC-6) with scalded rat serum (SRS) collected at either 12 or 24 h after injury caused a disruption in the integrity of the confluent culture and induced the appearance of large denuded areas. SRS also decreased DNA synthesis and delayed wound closure in an in vitro wound-healing model. The thermal injury-induced changes in intestinal mucosal morphology and epithelial cell growth characteristics described in this study may underlie, in part, the mechanism(s) involved in the diminished absorption of nutrients, increased intestinal permeability, and sepsis in patients with thermal injury.

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