BMP10 expression in WT and Bmp9-KO mice plasma. (A-B) BMP10 levels were measured from pooled diluted plasma (1/20) taken from WT OF1 mice at the indicated developmental stages (A) and from WT (n = 9) and Bmp9-KO (n = 14) P5 pups (B) with a murine BMP10 ELISA. Error bars show SEM.