source studies Blood 254 Cultured cells 121 Liver 71 Feces 48 Muscle 47 Heart 38 Brain 36 Urine 34 Kidney 25 Macrophages 22 Lung 22 Cerebrospinal fluid 16 Bacterial cells 14 Cecum 13 Intestine 12 CSF 10 Eye tissue 9 Unspecified 8 Colon 7 Spleen 7 Cells 7 Bone marrow 7 Adipose tissue 7 Ovarian cancer cells 6 T-cells 6 Tumor cells 6 Hippocampus 5 Water 5 Fibroblast cells 5 Prostate 4