RT-PCR of human and murine megakaryocytes and platelets. (A) Murine RT-PCR studies of total RNA from (1) megakaryocyte, (2) platelets, (3) WBCs, (4) NIH-3T3 cells, known to express LRP1,²⁰  and (5) water for LRP1 (first gel), PF4 (second gel), and ITGB2 (third gel). Expected band size is approximately 400 base pair (bp) for LRP1 and ITGB2, and approximately 300 bp for PF4. White space indicates where lanes were removed for ease of presentation. (B) Human RT-PCR studies of total RNA from (6) megakaryocytes, (7) platelets, (8) WBCs, (9) 293T cells, embryonic kidney line known to express LRP1,²¹  (10) water, and (11) no reverse transcriptase controls for LRP1 (first gel), PF4 (second gel), and ITGB2 (third gel).