RT-PCR analysis and platelet counts in liver specific Tpo-KO mice. Liver from Tpo-KO mice or wild-type littermates were transplanted in normal recipients, as previously described. (A) Tpo mRNA expression was analyzed in the kidney (K), liver (L), muscle (M), and spleen (S) by RT-PCR. (B) Platelet counts were measured from retroorbital bleeds 12 weeks after transplant; n = 6 mice per group.