What are precision-cut tissues slices?
The term “precision-cut tissue slices” or PCTS refers to live or fresh tissue slices that are cut to a precise thickness—hence the description “precision-cut.” These slices are used for functional studies, such as bronchial contractions in lung, renal fibrosis, and livery disease. PCTS are kept “alive” as organotypic culture slices, and are used in the fields of pharmacology, toxicology, and physiology.
For instance, here is a precision-cut lung slice (Figure 1) made with the Compresstome® for studying bronchial constriction:
How does the Compresstome® make precision-cut tissue slices?
Since its development in 2004, the Compresstome® has been widely used by researchers worldwide for making PCTS. Advantages of our vibratome include:
- Continuous automated slicing (with the option to select the “single slice” mode)
- Minimal fine tunings required (easy to use!)
- Simple engineering, fewer steps in preparing to cutting and slice retrieval
- Excellent subsequent tissue slice biological performances
- Doubles length of slice healthy and cell survival in culture
When were precision-cut tissue slices first developed?
Interest first developed in the 1950s for making lung tissue organotypic cultures. The respiratory tract requires physiological specificity compared to other organs, because the lung relied on cyclic movements that induce tissue stretching. Lung tissue remains healthy only if it is properly exposed to gaseous elements on the epithelial side. One main challenge of cutting precision-cut lung slices (PCLS) was that the alveolar walls would collapse after removal from the thorax. Therefore, development of PCLS allowed for the study and modeling of lung mechanics, smooth muscle activity, and ciliated cell function.
More recently, the technique of making precision-cut tissue slices has been applied to many other organs, and PCTS is becoming increasingly popular. In particular, precision-cut slices for liver, kidney, and gastrointestinal tissue have allowed researchers to use organotypic culture slices to study metabolism, toxicity, and drug-induced side effects.
Live brain and spinal cord slices (also called fresh or acute slices) have also been used for decades for experiments like electrophysiology and calcium imaging. However, the term “precision-cut” has not been commonly used to describe slices made for neurobiology.
What are precision-cut tissue slices used for?
PCTS are an efficient and valuable method to study live organ experimentation, particularly for metabolism, toxicity, drug therapy, drug screening, and pharmaceutical applications. Precision-cut tissue slices have been used to study organs of many species, including mice, cattle, monkeys, sheep, horses, and humans. Due to its growing popularity in research, PCTS is increasingly being used as an ex vivo approach to visualize cell-cell interactions in organotypic cultures, while maintain the structural integrity of tissue architecture.
The Compresstome® has become instrumental in helping cut healthy, viable precision-cut tissue slices, including this sample of lung tissue:
What organs can be studied with precision-cut tissue slices?
Lung
New developments in precision-cut lung slices (PCLS) have allowed for better preservation of lung tissue explant culture slices. This gives researchers slices with better architecture for studies of respiratory function and metabolic activities. The major achievements in cutting PCLS, in which the Compresstome® has played a key part, include:
- Lung tissue agarose embedding prior to slicing, which allows for preservation of opened alveoli and better tissue compliance.
- Coring and slicing lung tissue requires pre-embedding with low meltng/geling agarose instilled through the trachea at 37°C, following by subsequent cooling at room temperature or 4°C.
- Agarose is released from the tissue slice upon incubation at 37°C.
- Resulting slices proved to preserve opened alveoli during culture and incubation periods.
Almost all immune cell types, including macrophages, neutrophils, and T cells are present in PCLS and maintain their normal structures. In addition, PCLS can also be used to study calcium signaling and contractility of airway and smooth muscle cells.
In humans, PCLS allow for the study of respiratory diseases, both chronic (such as COPD) and acute (such as asthma) conditions.
Kidney
Precision-cut kidney slices (PCKS) have been used in the study of renal fibrosis, and have proven to be better than in vitro models using homogeneous cell populations which poorly mimic kidney architecture. In the kidney, precision-cut tissue slices are great for pharmacotoxicology studies, especially to screen for efficacy of therapeutic drugs ex vivo using homogenous cell populations, which poorly mimic kidney conditions like fibrosis.
Heart
Precision-cut heart slices have been widely used to study myocyte electrophysiology in acutely cut live slices. For a video tutorial of how to cut live cardiac slices with the Compresstome(R), please visit:
https://www.youtube.com/watch?v=Q0PT37BPles
Here is what a precision-cut heart slice looks like with beating cardiac cells:
Other organs
Precision-cut tissue slices can be made from liver, spleen, pancreas, and the gastrointestinal tract for experiments in pharmacology, toxicology, and physiology. Contact us for protocols and references that have used the Compresstome® vibratome for these organ systems!