While the causality of this association remains to be elucidated, prior work suggests that fibronectin fiber relaxation may follow neutrophil infiltration in acute inflammation models.[91] In glioblastoma, recent findings indicate that endothelial cells interact strongly with monocyte‐derived macrophages (regardless of M1/M2 status) infiltrating from the vasculature, but not with resident microglia.[87] Thus, CD45+/CD68+ macrophages adjacent to untensed fibronectin may include microglia. The gene discussed is FN1; the disease is glioblastoma.