Caco-2/HT29-MTX co-cultured cells as a model for studying physiological properties and toxin-induced effects on intestinal cells

Abstract

Infectious gastrointestinal diseases are frequently caused by toxins secreted by pathogens which may impair physiological functions of the intestines, for instance by cholera toxin or by heat-labile enterotoxin. To obtain a functional model of the human intestinal epithelium for studying toxin-induced disease mechanisms, differentiated enterocyte-like Caco-2 cells were co-cultured with goblet cell-like HT29-MTX cells. These co-cultures formed a functional epithelial barrier, as characterized by a high electrical resistance and the presence of physiological intestinal properties such as glucose transport and chloride secretion which could be demonstrated electrophysiologically and by measuring protein expression. When the tissues were exposed to cholera toxin or heat-labile enterotoxin in the Ussing chamber, cholera toxin incubation resulted in an increase in short-circuit currents, indicating an increase in apical chloride secretion. This is in line with typical cholera toxin-induced secretory diarrhea in humans, while heat-labile enterotoxin only showed an increase in short-circuit-current in Caco-2 cells. This study characterizes for the first time the simultaneous measurement of physiological properties on a functional and structural level combined with the epithelial responses to bacterial toxins. In conclusion, using this model, physiological responses of the intestine to bacterial toxins can be investigated and characterized. Therefore, this model can serve as an alternative to the use of laboratory animals for characterizing pathophysiological mechanisms of enterotoxins at the intestinal level.

Yeast-Fermented Rapeseed Meal Extract Is Able to Reduce Inflammation and Oxidative Stress Caused by Escherichia coli Lipopolysaccharides and to Replace ZnO in Caco-2/HTX29 Co-Culture Cells

“…HT29-MTX cells (ECACC, European Collection of Authenticated Cell Cultures, Salisbury, UK) were cultured in RPMI-1640 medium containing 10% fetal bovine serum, 1% ( v / v ) nonessential amino acids, 2 mM L-glutamine, and 1% antibiotic–antimycotic solution. For co-culture experiments, the cells were seeded in a 9:1 (Caco-2:HT29-MTX) ratio [ 51 ] and cultured until confluence in MEM medium containing 10% fetal bovine serum, 1% ( v / v ) nonessential amino acids, 2 mM L-glutamine, and 1% antibiotic–antimycotic solution at 37 °C in a 5% CO 2 humidified atmosphere, with the culture medium being changed every three days. The cells were cultured at a concentration of 0.1 × 10 6 cells/mL in 24-well culture plates (Nunc).…”

Microbial Imbalance Induces Inflammation by Promoting Salmonella Penetration through the Mucosal Barrier

“…This removal is balanced by the production of mucus by goblet cells. Some in vitro systems utilize cocultures of HT-29 and Caco-2 cells to constantly produce mucus. , These cells produce a mucus layer, however, that is considerably thinner than the physiological layer in the large intestines. In addition, the production of mucus must be balanced by physical removal to maintain a constant thickness.…”

Recent advance of in vitro models in natural phytochemicals absorption and metabolism

“…In addition, A triple co‐culture model was proposed, including Caco‐2, Raji‐B and HT29‐MTX cell, is closer to intestinal epithelium because Raji‐B can induce the phenotype of M cells, and HT29‐MTX cells are similar to goblet cell [49]. These three kinds of cells are the same as the human intestine, and they are simulated closer to the human body [50]. Selby‐Pham et al [51] use co‐cultures of Caco‐2 and HT29‐MTX‐E12 cells were used to determine the apparent permeability (Papp) of dietary phytochemicals extracts in the single layer of co‐cultured cells.…”