Dr. Liu’s research is focused on developmental differences of platelets and thrombopoiesis, with the aim of advancing our understanding of neonatal thrombocytopenia. Previously, it was believed that fetal and neonatal megakaryocytes were incomplete in maturation due to their small size and their rapidly-growing progenitors. Dr. Liu's first accomplishment in this area demonstrated a unique uncoupling of enodomitosis and cytoplasmic maturation during fetal/neonatal megakaryopoiesis, which resulted in generating small, but fully mature, megakaryocytes. This finding was highlighted in an "Inside Blood" editorial review. His second research article revealed that prolonging the lifespan of platelets provides a major mechanism for matching platelet mass expansion during fetal/neonatal development. These findings introduced a new paradigm: the rapid expansion of blood volume predisposes fetuses and neonates to develop severe thrombocytopenia. Dr. Liu is further exploring the mechanisms that regulate such a characteristic process of fetal/neonatal thrombopoiesis. His major focus is on the developmental difference in expression of microRNA let7B and its role in thrombopoiesis.
Dr. Liu is also working on the influences of maternal antibodies against human platelet antigen-1A (HPA-1A) on megakaryopoiesis. Maternal HPA-1A antibodies account for over 80% of fetal/neonatal alloimmune thrombocytopenia (F/NAIT), with severe sequela. Intravenous immunoglobulin (IVIG) treatment is the therapy of choice for F/NAIT. However, over 20% of cases are nonresponsive to IVIG treatment. His study showed that the majority of maternal serum samples can suppress megakaryopoiesis in vitro by inducing cell death of immature megakaryocytes. His results also suggest an inverted correlation between the suppression of in vitro megakaryopoiesis and the outcomes of IVIG treatment indicated by postnatal peripheral platelet count. Dr. Liu's following studies will investigate the possible approaches to prevent megakaryocyte death caused by maternal antibodies, with a goal of improving the therapeutic outcomes of IVIG treatment.
Zhi-Jian Liu received his Ph.D. degree in Pharmaceutical Sciences (Pharmacology) at the University of South Carolina, College of Pharmacy. He finished his first postdoctoral training in gene therapy at Columbia University Medical Center. In 2008, he joined Dr. Martha Sola-Visner’s group at Boston Children’s Hospital, Division of Newborn Medicine and Harvard Medical School, Department of Pediatrics, as a postdoctoral research fellow. In 2011, he was awarded a “William Randolph Hearst Foundation Award for Pre- and Peri-natal Medicine” fellowship for his research on fetal/neonatal alloimmune thrombocytopenia. In 2012, he was appointed staff scientist and Instructor in Pediatrics at Boston Children’s Hospital and Harvard Medical School.