Samuel E. Lux IV, MD
Chief Emeritus, Division of Hematology/Oncology, Boston Children's Hospital
Vice-Chair for Research, Department of Medicine, Boston Children's Hospital
Director, Internship Selection Committee, Boston Children's Hospital
Robert A. Stranahan Professor of Pediatrics, Harvard Medical School
Boston Children's Hospital
300 Longwood Ave.
Boston, MA 02115
Boston Children's Hospital, 1972
Boston Children's Hospital, 1969
University of Kansas School of Medicine, 1967
Dr. Lux received his MD in 1967 from Kansas University School of Medicine. From 1967 to 1969, he did his internship and residency at Boston Children's Hospital. He subsequently studied protein chemistry at the National Institutes of Health, before returning to Boston Children's in 1972 for fellowship training in Hematology/Oncology. He was Chief of the Hematology/Oncology Division at Boston Children's from 1985 through 2007. His research focuses on red blood cell membrane disorders and anemias.
Structure and Function of Membrane Skeletons
Our laboratory focuses on the organization and functions of the spectrin-based membrane skeleton. Current work is directed at three related problems:Ankyrin functions. Ankyrins link integral membrane proteins to the spectrin-based membrane skeleton. Members of the laboratory first cloned red cell ankyrin or Ank1 and subsequently cloned and characterized Ank3, the major nonerythroid ankyrin. To understand how ankyrins work and what they do, we are knocking-out various ankyrins and replacing them with modified or chimeric ankyrins. We also are studying the interactions and functions of a 'death domain' that is found in all ankyrins.Hereditary defects in membrane skeleton proteins. During the past decade our laboratory and others have shown that hereditary spherocytosis is caused by defects in the connections that attach the membrane skeleton to the overlying lipid bilayer. To test the pathophysiology, we produced mice that lack the erythroid anion exchanger (AE1), the principal Ank1 ligand. Although much experimental evidence indicates that AE1 is required for membrane skeleton assembly, AE1-/- red blood cells have a normal membrane skeleton. Even so, they shed bilayer lipids at a prodigious rate, leading to extreme hemolysis and spherocytosis. This indicates that AE1 and probably other integral membrane proteins have a 'lipid-anchoring' function. Members of our laboratory are currently testing whether the anemia and lipid loss can be rescued by expression in situ of various modified AE1s.Organelle membrane skeletons. There is increasing evidence from our laboratory and others that some organelles (e.g., lysosomes, Golgi) also have membrane skeletons. This is a fertile area for investigation since, so far, almost nothing is known about the structure or function of these skeletons. In addition, we recently discovered two new spectrins (bIII and bIV) that are bound to the Golgi or a subset of cytoplasmic vesicles or both. We are currently characterizing the interactions of these spectrins and testing the hypothesis that they are involved in the vesicle trafficking.