IDH1 and glioblastoma: Specifically, Dejaegher and colleagues compared immune infiltration between different GBM methylation patterns (RTK I, RTK II, IDH, and Mesenchymal) and found that the IDH methylation pattern was associated with the lowest levels of CD3 and CD8 T cell infiltration, while the mesenchymal methylation pattern had the highest overall levels of CD8 T cell infiltration [34,35].