In Vitro Culturing Technique for Studying Cellular Dynamics in Zebrafish Scales

Summary

This protocol offers a method to study cellular dynamics using a simple in vitro culture technique. It provides an opportunity for zebrafish researchers and educators to study cellular processes, such as those related to bone homeostasis and basic cell biology, by visualizing fluorescent nuclei and apoptotic cells within the scales.

Abstract

Zebrafish scales offer a variety of advantages for use in standard laboratories for teaching and research purposes. Scales are easily collected without the need for euthanasia, regenerate within a couple of weeks, and are translucent and small, allowing them to be viewed using a standard microscope. Zebrafish scales are especially useful in educational environments, as they provide a unique opportunity for students to engage in hands-on learning experiences, particularly in understanding cellular dynamics and in vitro culturing methods. The main objective of this protocol is to describe a method for collecting and maintaining zebrafish scales in culture for use in a variety of biological studies using basic laboratory equipment. Additionally, the protocol details their use in understanding bone homeostasis by examining the activity of bone cells involved in bone resorption and deposition. It also includes additional protocols for general techniques, such as the visualization of nuclei and apoptotic cells. The in vitro culturing protocol produces reliable results with minimal reagents and equipment. This article discusses the benefits of using in vitro cultures of zebrafish scales to foster scientific inquiry and outlines the resources needed to support their integration into educational settings.

Introduction

In recent years, zebrafish (Danio rerio) have emerged as a valuable model organism in various scientific fields, including genetics, developmental biology, and toxicology^1,2,3. Zebrafish are small tropical freshwater fish native to the rivers of Southeast Asia⁴. They have become a popular model organism in biology due to their easy maintenance, small size, rapid reproductive cycle, and translucent embryos¹. This allows for easy observation of their internal development, making them ideal for studying various biological ....

Protocol

All protocols described here follow the Canadian Council on Animal Care guidelines and were approved annually by the Saint Mary's University/Mount Saint Vincent University Animal Care committee under protocol numbers 20-14 and 21-12. Before carrying out this protocol, users must ensure that federal and provincial guidelines on using animals in research or teaching are followed²³. The details of the reagents and equipment used in this study are listed in the Table of Materials........

Discussion

Zebrafish scales are an easily accessible in vitro model to study a variety of different biological processes that can be maintained for up to 2 days using a culturing method and an incubator to simulate their natural environment¹¹. Scales have a regular and proportional distribution of cells present, which enables researchers to view, count, and label cells and to conduct simple cell biology experiments using basic laboratory equipment. Furthermore, the entire scale is easily visible wit.......

Materials

Name	Company	Catalog Number	Comments
0.2 mL tubes	n/a	n/a
37% HCl	EMD	HX0603-4	For pH stabilization and prepration of PRS
Concave slide	n/a	n/a
DAPI	Vectashield	H-1200	For cell nuclei visualization
Diazonium salt (Fast Blue B)	Sigma	D9805	For AP substrate solution
Dulbecco's Modified Eagle Medium (DMEM) powder	Sigma	D5523	For scale culture media
Ethyl 3-aminobenzoate methanesulfonate (MS222)	Sigma	E10521	For preparation of 0.1% MS222
Fetal bovine serum	Sigma	F4135	For scale culture media
Fluorescence microscope	n/a	n/a
Glacial acetic acid	Fisher	A38 212	For acetate buffer
Glycerol	VWR	BDH1172-4LP	For 80% glycerol - storage scales
HEPES	ThermoFisher	15630106	For scale culture media
Hot plate	n/a	n/a
KCl	Sigma	P217-10	For preparation of PBS
Lysotracker	ThermoFisher	L7528	For lysosomes  visualization
Maleic acid	Sigma	M0375	For Tris-Maleate buffer
Micropipette	n/a	n/a
N,N-dimethylformamide	Sigma	319937	For AP substrate solution
N,N-dimethylformamide	Sigma	319937	For Enzyme Substrate Solution
Na2HPO4	EMD	SX0720-1	For preparation of PBS
NaCl	Sigma	S9888	For preparation of PBS
NaNO2	Sigma	S-2252	For 4% NaNO2
NaOH	Sigma	S5881	For preparation of 4% PFA
NaOH	Sigma	S5881	For scale fixation and pH stabilization
Napthol-AS-TR-phosphate	Sigma	N6125	For AP substrate solution
Napthol-AS-TR-phosphate	Sigma	N6125	For Enzyme Substrate Solution
Pararosaniline hydrochloride	Sigma	P3750	For PRS
Penicillin-streptomycin 5000 units penicillin and 5mg streptomyocin/ml	ThermoFisher	15140122	For scale culture media
Personal protective equipment (PPE): disposable nitrile gloves, safety glasses/splash goggles and lab coat.	n/a	n/a
PFA	Sigma	P6148	For scale fixation
Sodium acetate	Sigma	S2889	For acetate buffer
Standard compound microscope	n/a	n/a
Stir plate	n/a	n/a
Tartaric acid	Sigma	T6521	For Tartrate buffer
Tris base	Roche	03 118 142 001	For Tris-Maleate buffer