Scalable culture techniques to generate large numbers of purified human Schwann cells for clinical trials in human spinal cord and peripheral nerve injuries

J Neurosurg Spine, 2021 · DOI: 10.3171/2020.11.SPINE201433 · Published: September 3, 2021

Spinal Cord Injury Regenerative Medicine Neurology

Simple Explanation

Schwann cells (SCs) are support cells in the peripheral nervous system that help regenerate nerve fibers after injury. Because of this, they are being investigated as a transplant therapy for spinal cord injuries (SCIs) and peripheral nerve injuries (PNIs). To use SCs as a therapy, researchers need to be able to produce large quantities of them in a way that meets strict quality and safety standards. This paper presents a method for producing clinical-grade SCs that are compliant with Current Good Manufacturing Practices (CGMPs). The authors analyzed data from 18 clinical trial participants who received autologous SC transplantation for SCIs or PNIs. They found that their method produced a large number of SCs with high viability and purity.

Study Duration

Not specified

Participants

18 clinical trial participants with subacute SCI (n = 7), chronic SCI (n = 8), or PNIs (n = 3)

Evidence Level

Not specified

Key Findings

1
The study produced an average yield of 87.2 ± 89.2 million cells at passage 2 (P2) and 150.9 ± 129.9 million cells at passage 3 (P3) with high viability and purity.
2
Cell counts and expansion rates increased with each passage, with the most significant expansion occurring between passages 2 and 3.
3
Longer nerve harvests correlated significantly with greater cell yields at passage 0 (P0) and passage 1 (P1).

Research Summary

This study presents a CGMP-compliant method for manufacturing autologous Schwann cells (SCs) for clinical use in treating spinal cord injuries (SCIs), peripheral nerve injuries (PNIs), and other conditions. The method involves harvesting a portion of a patient’s sural nerve, isolating and expanding the SCs in culture, and then transplanting them back into the patient. The process yields a large number of highly viable and pure SCs. The authors found that longer nerve harvests correlated with higher cell yields and that cell expansion rates increased with each passage. The final cell product is a suspension with excellent handling properties suitable for clinical application.

Practical Implications

Clinical Translation

The reliable CGMP-compliant manufacturing method can be used to generate large quantities of autologous SCs for clinical trials and potential regenerative treatments.

Optimized Cell Production

The optimized protocol ensures high cell viability and purity, which are crucial for effective cell transplantation therapies.

Peripheral Nerve Repair

The study provides a method for obtaining viable and pure SC cultures from both uninjured and injured peripheral nerves, demonstrating its potential for peripheral nerve repair applications.

Study Limitations

1
The study did not rule out genomic aberrations such as microdeletion/microduplication, subtle structural rearrangement, and low-degree mosaicism with karyotype analysis.
2
The long-term efficacy of the transplanted Schwann cells was not evaluated in this study.
3
The manufacturing process is complex and requires specialized facilities and expertise.

Your Feedback

Was this summary helpful?

Back to Spinal Cord Injury