Culturing The Multi-Faceted Enterocytes
Enterocytes have been shown to function in digestion by taking up water, nutrients, ions, vitamins as well as absorbing unconjugated bile salts. Apart from this role in the digestive system, research by Miron and Cristea in Clinical and experimental immunology in 2012 showed that these cells also function in immunity. They function as a barrier to prevent toxins or microbes from the intestinal lumen into the tissue. They also allow what is termed as immunological tolerance towards the proteins that are ingested. There is a cooperation between the MALT: the mucosa-associated lymphoid tissue of the intestine and the enterocytes to ensure that there is no immunological reaction for the antigens of the diet and gut microbes.
The cells secrete chemokines and cytokines to cause the activation and recruitment of immune cells. Early research in 1991 in The Journal of Immunology showed that enterocytes also show the expression of CD1D that is similar to MHC class I to hence function as antigen presenting cells. Thus, studying enterocytes can allow for exploring a wide range of biological details such as differentiation, transport, interactions, permeability and apoptosis. The fields of immunology, stem cells, pharmacology and gene therapy can benefit from such cultures to advance research and explore the nuances of life sciences.
The culturing of intestinal epithelial cells needs attention in several aspects: the presence of microbes in the intestine increases the chances of contamination of cultures. The cells undergo renewal in 4-5 days making it a dynamic layer: this makes them differentiated by the time they reach the tip. Thus, the culture of these cells requires care to be taken on these aspects.
There are cell lines from animals such as rodents, yet the use of such lines become questionable given that the expression of enzymes of the brush border and their regulation are different between that of animals and humans. There are also differences between the basement membrane making the results of research in such animal lines a challenge. There are cell lines derived from cancers such as HT29 that again have the issues of transformation.
A team led by Priti Chougule reported the primary culture of enterocytes in the Scandinavian Journal of Gastroenterology in 2012. The fat was removed from bowel specimens from cadavers followed by washing the lumen and culturing in medium. The migration of the cells was seen in 6 days of the culture that were separated using an epithelial market called EpCAM. Such cells showed the presence of interesting immune cells such as adhesion molecules and TLRs.
A point to be noted to culture these cells is to wash the lumen with antibiotic buffers and lowering excess contact with intestinal tissue. Such cultures can highlight the changes in ulcerative colitis and other bowel diseases. This becomes significant given that ulcerative colitis targets 0.5 to 31.5 per 100000 people across the world, according to Burisch in the Current opinion in gastroenterology.
The fields of immunology, stem cells, pharmacology and gene therapy can benefit from such cultures to advance research and explore the nuances of life sciences.
References:
Miron, N., & Cristea, V. (2012). Enterocytes: active cells in tolerance to food and microbial antigens in the gut. Clinical and experimental immunology, 167(3), 405–412.
Blumberg RS, Terhorst C, Bleicher P, Expression of a nonpolymorphic MHC class I-like molecule, CD1D, by human intestinal epithelial cells. The Journal of Immunology 1991;147:2518–24.
Priti Chougule, Gustaf Herlenius, Nidia Maritza Hernandez, Pradeep B Patil, Bo Xu & Suchitra Sumitran-Holgersson (2012) Isolation and characterization of human primary enterocytes from small intestine using a novel method, Scandinavian Journal of Gastroenterology, 47:11, 1334-1343.
Burisch J, Munkholm P. Inflammatory bowel disease epidemiology. Current opinion in gastroenterology. 2013;29:357–362.
Linda Chia-Hui Yu, Jin-Town Wang, Shu-Chen Wei, Yen-Hsuan Ni. Host-microbial interactions and regulation of intestinal epithelial barrier function: From physiology to pathology. World Journal of Gastrointestinal Pathophysiology 2012; 3(1): 27-43.
