Figure 2.

Human urinary exosomal preparations characterized by immunoblotting. (A–E) Human urine was collected from subjects listed in Table 1. Immunoblotting of lysates of human urinary particles isolated using ultracentrifugation and remaining unpurified (UNp) or isolated via ultracentrifugation and then fraction 6 (F6) and fraction 7 (F7) collected by SEC column-purification. Immunoblotting controls were exosome-depleted human urine (–EXO Sup) and PBS used to wash exosomal preparations (–EXO PBS). Blots were probed for the exosome-positive marker CD81 and exosome-negative marker calnexin.