source studies Blood 48 Liver 18 Brain 11 Cultured cells 9 Eye tissue 8 Muscle 7 Macrophages 6 Heart 6 Feces 5 Adipose tissue 4 Lung 3 Ventricles 2 HeLa cells 2 Mitochondria 2 Optic nerve 2 Skin 2 T-cells 2 Intestine 1 Kidney 1 Blood Serum 1 Bacterial cells 1 Back of Eye 1 Microglia 1 Microglia cells 1 Tumor cells 1 Atria 1 Tumor tissue 1 Ovarian cancer cells 1 Retina 1 Urine 1