Isolation of Primary Myofibroblasts from Mouse and Human Colon Tissue

Summary

The myofibroblast is an influential stromal cell of the gastrointestinal tract that regulates important physiologic processes in both normal and disease states. We describe a technique that allows for the isolation of primary myofibroblasts from both mouse and human colon tissue, which can be utilized for in vitro experimentation.

Abstract

The myofibroblast is a stromal cell of the gastrointestinal (GI) tract that has been gaining considerable attention for its critical role in many GI functions. While several myofibroblast cell lines are commercially available to study these cells in vitro, research results from a cell line exposed to experimental cell culture conditions have inherent limitations due to the overly reductionist nature of the work. Use of primary myofibroblasts offers a great advantage in terms of confirming experimental findings identified in a cell line. Isolation of primary myofibroblasts from an animal model allows for the study of myofibroblasts under conditions that more closely mimic the disease state being studied. Isolation of primary myofibroblasts from human colon tissue provides arguably the most relevant experimental data, since the cells come directly from patients with the underlying disease. We describe a well-established technique that can be utilized to isolate primary myofibroblasts from both mouse and human colon tissue. These isolated cells have been characterized to be alpha-smooth muscle actin and vimentin-positive, and desmin-negative, consistent with subepithelial intestinal myofibroblasts. Primary myofibroblast cells can be grown in cell culture and used for experimental purposes over a limited number of passages.

Introduction

The regulation of gastrointestinal (GI) tract function involves complex, dynamic interactions between the mucosal layer and its underlying mesenchyme. These interactions normally serve to maintain homeostasis but may also lead to the development of disease states under pathologic conditions¹. Myofibroblasts are a subpopulation of stromal cells located subjacent to the epithelial layer that communicate in a paracrine fashion with surrounding cell subpopulations to regulate a number of critical GI tract processes that include mucosal regeneration, repair, and fibrosis².

The 18Co cell line is an example of a human colonic....

Protocol

1. Obtain Colon Tissue

Mouse

A protocol to perform animal experiments, detailing the rationale and objectives of the research, was submitted and approved by our institutional Office of Animal Research Oversight.

1. Euthanize the mouse with inhaled isoflurane followed by cervical dislocation.
2. Make a ventral midline incision, retract the small bowel away and identify the colon. Retract the bladder and uterus (if present) laterally and identify the pubic bone and cut it with fine scissors to expose the rectum.
3. Dissect the dorsal mesentery of the rectum off of the colon and mobilize the colo....

Results

Once isolated, primary human myofibroblasts can be grown in cell culture and used over a limited number of passages (up to passage 4). These cells are characterized as being a-smooth muscle actin and vimentin positive, and desmin-negative (Figure 1A), consistent with intestinal subepithelial myofibroblasts^5,7. They also have a characteristic stellate morphology (Figure 1B). Primary myofibroblasts can then be used to confirm experimental findings identified in a cell line. This.......

Discussion

The general technique is similar when using either mouse or human colon. This technique can also be used to isolate myofibroblasts from the small intestine. Specific details for the isolation of myofibroblasts from 1. mouse and 2. human colon are discussed below.

1. Mouse Colon

Irrigation of the mouse colon is facilitated by attaching a 4 in, 16 G Popper blunt-end needle to one end of the colon. This also helps when cutting the colon lengthwise. You can accordion the c.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Name of the reagent	Company	Catalogue number	Comments (optional)
Dispase I	Invitrogen/GIBCO	#17105-041
Collagenase D	Roche	#1 088 858
4 in, 16 G Popper blunt-end needle	Fisher	#14-825-16K