For instance, metastasis requires tissue remodeling and local invasiveness as well as intravasation of tumors cells into blood and lymph, and extravasation to sites of metastasis; similarly in response to infections complement C5a helps to remodel tissue to increase invasiveness of immune cells, and increases extravasation and intravasation of immune cells both into the infected tissue and into blood and lymph nodes. Here, C5 is linked to infection.