Cell Sorter Cleaning Practices and Their Impact on Instrument Sterility

Research on cell sorting often overlooks the impact of instrument maintenance. Prior studies have focused on sorting parameters like pressure and temperature. However, the role of fluidic contamination in altering experimental outcomes remains unclear. This gap motivated a new investigation into sorter sterility. Existing knowledge shows contamination can affect molecular assays. Yet, no prior work had resolved how common such issues are in shared labs. The variability in results across sites suggests a need for standardized cleaning. This study aimed to address that uncertainty in a controlled manner.

The goal was to assess how cell sorters are maintained and whether they harbor contaminants. The focus was on bacteria, endotoxins, and RNases in shared lab settings. The study aimed to determine if these contaminants affect downstream assays. It also sought to evaluate a specific decontamination method. The motivation came from observed variability in gene expression results. The team wanted to isolate the role of fluidic contamination. No prior work had tested hydrogen peroxide's long-term efficacy. This study aimed to fill that gap with a multisite approach.

The study involved a multisite evaluation of cell sorters in shared resource labs. Researchers collected data on current cleaning and maintenance practices. They tested for RNase activity, bacteria, and endotoxin contamination. A hydrogen peroxide cleaning protocol was applied and monitored. Contamination levels were measured before and after the procedure. The team analyzed the data to assess the presence of contaminants. They also evaluated the effectiveness of the cleaning method over time. The approach combined standardized testing with practical lab observations.

Most sorters tested were free of RNase activity and bacterial contamination. However, endotoxin contamination was detected in a significant number of instruments. The hydrogen peroxide cleaning method showed initial success in reducing endotoxin. But the effect was short-lived, with contamination recurring after a few days. The presence of endotoxin varied across sites, even with similar sorting conditions. These findings suggest that endotoxin is a persistent issue in shared labs. The cleaning protocol failed to provide long-term sterility solutions. The results highlight the need for improved decontamination strategies.

The study confirmed that endotoxin contamination is common in cell sorters. The hydrogen peroxide method offered only temporary decontamination. These findings suggest that current cleaning practices may be insufficient. The authors propose that endotoxin is a critical factor in downstream assays. They emphasize the need for better maintenance protocols in shared labs. No prior work had shown such widespread contamination in this context. The results align with the observed variability in gene expression studies. The authors recommend further investigation into alternative cleaning methods.