Fig 1: Functional role of scavenger receptors in myelin phagocytosis in vitro. MSR1, CXCL16, OLR1, and CD68 were downregulated with antisense oligonucleotides in the human macrophage cell line THP-1. Silencing efficiency was determined on mRNA level with quantitative polymerase chain reaction (A) and on protein level with immunocytochemistry [(B); only shown for MSR1]. Uptake of pHrodo-labeled myelin was validated by flow cytometry (C) and compared for myelin obtained from control and multiple sclerosis (MS) brain tissue (D). The number of cells that had phagocytosed myelin, and the total amount of myelin phagocytosed (geomean pHrodo) were calculated. The number of independent experiments (n) was 6 (MSR1), 4 (CXCL16), 3 (OLR1), and 3 (CD68). (E) Fucoidan was used to inhibit a broad spectrum of scavenger receptors in THP-1 cells. Provided is the number of cells that had phagocytosed myelin, the total amount of myelin phagocytosed (geomean pHrodo), and the viability of cells at the time point of analysis (n = 3). Scale bar in panel (B) = 200 µm *p < 0.05, **p < 0.01, ***p < 0.005.