Single-cell studies have revolutionized the way we understand diseases by showing how individual cells behave differently, even within the same tissue. However, these studies often rely on freshly collected samples, which can make global collaborations and research on archived tissues challenging. A recent study tackles this problem by creating a protocol that allows high-quality single-cell and single-nucleus analyses from preserved human skeletal muscle tissue.

The Challenge

Skeletal muscle is a complex tissue made up of many different cell types, each playing a critical role in movement and metabolism. Studying these cells at the single-cell level helps researchers understand diseases like muscular dystrophy and other muscle-related conditions. The catch? Most single-cell techniques need fresh tissue, which isn’t always possible in large-scale, multi-center studies or when relying on stored tissue samples.

A New Solution

To overcome this hurdle, researchers at the Center for Research on Genomics and Global Health have developed a method using Allprotect® Tissue Reagent, a preservative that keeps tissue stable. This allows them to extract high-quality cells and nuclei from archived skeletal muscle samples. After confirming the integrity of nuclei using fluorescent imaging, the team tested four variations of their protocol to compare the quality of data obtained from cells versus nuclei and from different enrichment methods.

Experimental design

a Needle biopsy tissue was collected from adult individuals enrolled in the AADM study, placed in ATR, and transitioned to longer-term storage temperatures before shipment to a central processing center. b Single-cell capture protocol. Samples from two donors were pooled before manual dissociation and subsequent processing. c Data analysis pipeline as detailed in Methods.

Key Findings

1. Comparable Data: Whether they used cells or nuclei, the transcriptional profiles (gene activity patterns) were nearly identical. Both approaches successfully identified eight distinct cell types present in skeletal muscle.
2. Sorting vs. Filtering: Flow cytometry sorting, a method that separates cells or nuclei based on their properties, yielded higher-quality material. However, it also reduced the total amount of material available for analysis.
3. Practical Benefits: This protocol makes it easier to study archived samples without compromising on data quality, offering a way to include samples from multiple global locations.

The Importance

This new protocol bridges a critical gap in single-cell research, allowing scientists to analyze stored tissue without losing important details. It opens doors to studying rare diseases and archived samples collected over decades, enabling new insights into how diseases develop and progress.

Looking Ahead

By standardizing methods for working with preserved tissue, this research streamlines collaboration across labs worldwide. It ensures that even stored samples can contribute to cutting-edge discoveries in cellular biology and disease research.