Researchers have developed a method using virus-like particles to perform precise gene engineering in primary human myeloid cells. Myeloid cells, which include macrophages and dendritic cells, are critical components of the immune system and targets for cancer immunotherapy. Until now, these cells were difficult to modify because traditional methods like nucleofection often compromised cell viability or failed to maintain the functional state of the cells after processing.
This new technique bypasses those limitations. By using virus-like particles to deliver CRISPR-Cas9 components, scientists achieved efficient gene knockout and editing without the negative effects associated with standard physical delivery methods. This approach preserves the health and function of the cells, allowing them to remain effective in laboratory assays and therapeutic applications.
Beyond simple gene editing, the study demonstrates the ability to conduct pooled CRISPR screens in these primary cells. This allows for high-throughput identification of genes that regulate immune responses, such as tumor necrosis factor production and CD80 surface expression. The research provides a map of regulatory networks in human myeloid cells, which were previously difficult to study at scale.
This platform also enables the generation of chimeric antigen receptor macrophages with improved anti-tumor activity. By using this gene-editing tool to ablate specific genes like TNFAIP3, the researchers observed enhanced immune responses in co-culture models with tumor cells. The results suggest this method is a practical way to develop and study modified immune cells for future cancer treatments.