Kidney injury molecule–1 is a phosphatidylserine receptor that confers a phagocytic phenotype on epithelial cells
J. Clin. Invest. Takaharu Ichimura, et al. 118:1657 doi:10.1172/JCI34487 [Go to this article.]

Figure 4
Quantitative analysis of KIM-1–mediated apoptotic cell and necrotic material phagocytosis. Flow cytometric plots of green fluorescence against side scatter (SSC) for KIM1-PK1 and pcDNA-PK1 epithelial cells that have ingested fluorescently labeled (CMFDA) apoptotic thymocytes (A), apoptotic LLC-PK1 cells (B), or necrotic debris (necrotic LLC-PK1 cells) (C) in a phagocytosis assay. Percentages represent the proportion of epithelial cells that have ingested fluorescently labeled material. KIM1-PK1 cells that have not ingested apoptotic cells or debris were used to define the gated area. Without coculture with necrotic cells, only 0.93% of KIM-1–expressing epithelial cells were identified in the gated area. (D) Flow cytometric plots of green fluorescence against side scatter for KIM1–tet-off MDCK epithelial cells that have ingested fluorescently labeled (CMFDA) apoptotic LLC-PK1 in a phagocytosis assay. MDCK cells were either treated with doxycycline (100 ng/ml) to inhibit expression of the KIM-1 (left panel) or no doxycycline was used (5 days), permitting high-level expression of KIM-1 (right panel). Values represent the percentage of epithelial cells that have ingested fluorescently labeled apoptotic cells. KIM1–tet-off MDCK cells that have not ingested apoptotic cells or debris were used to define no ingestion.