BACKGROUND

Current challenges in meningioma treatment, including post-surgical complications and cognitive impairments, highlight the need for new treatment alternatives. Immunological interventions have shown promise. However, there is a knowledge gap in characterizing infiltrating immune cells in meningioma and their interplay. Further studies on immune cells in single-cell suspensions from digested meningioma tissues could identify targetable mechanisms for non-surgical treatment options with fewer side effects. This study aimed to optimize a protocol for faster digestion of meningioma tissues into viable single-cell suspensions and to identify infiltrating immune cell populations.

METHODS

We modified a commercial kit intended for whole skin dissociation to digest resected meningioma tissues into viable single-cell suspensions. Tumor-infiltrating immune cell populations were characterized using flow cytometry.

RESULTS

Flow cytometry analyses revealed that the digested tissue was composed of viable immune cells, including predominantly CD14 macrophages and CD3 T cells, with minor populations of CD56 NK cells and CD19 B cells. In both of the two patient samples tested, half of the tumor-associated macrophages were TIM-3, with a small proportion co-expressing CD83. Women were more likely to have a lower proportion of immune cells, B cells, and NK cells. Female patients with a high proportion of immune cells had a higher proportion of macrophages.

CONCLUSION

We successfully optimized a protocol for generating single-cell suspensions with viable immune cells from meningioma tissues, revealing infiltrating antigen-presenting cells with an immunosuppressive phenotype, and lymphocytes. This short protocol allows advanced analyses of tumor-infiltrating cells using techniques such as single-cell RNA sequencing and flow cytometry, which require live, dissociated cells.