title: Visualizing red blood cell sickling and the effects of inhibition of sphingosine kinase 1 using soft X-ray tomography.
abstract: Sickle cell disease is a destructive genetic disorder characterized by the formation of fibrils of deoxygenated hemoglobin, leading to the red blood cell (RBC) morphology changes that underlie the clinical manifestations of this disease. Using cryogenic soft X-ray tomography (SXT), we characterized the morphology of sickled RBCs in terms of volume and the number of protrusions per cell. We were able to identify statistically a relationship between the number of protrusions and the volume of the cell, which is known to correlate to the severity of sickling. This structural polymorphism allows for the classification of the stages of the sickling process. Recent studies have shown that elevated sphingosine kinase 1 (Sphk1)-mediated sphingosine 1-phosphate production contributes to sickling. Here, we further demonstrate that compound 5C, an inhibitor of Sphk1, has anti-sickling properties. Additionally, the variation in cellular morphology upon treatment suggests that this drug acts to delay the sickling process. SXT is an effective tool that can be used to identify the morphology of the sickling process and assess the effectiveness of potential therapeutics.
authors: National Center for Macromolecular Imaging, Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
authors: Michele C
authors: MC
authors: Darrow
authors: Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
authors: Yujin
authors: Y
authors: Zhang
authors: Department of Anatomy, University of California San Francisco, San Francisco, CA 94143, USA Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
authors: Bertrand P
authors: BP
authors: Cinquin
authors: Department of Anatomy, University of California San Francisco, San Francisco, CA 94143, USA Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
authors: Elizabeth A
authors: EA
authors: Smith
authors: Department of Anatomy, University of California San Francisco, San Francisco, CA 94143, USA Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
authors: Rosanne
authors: R
authors: Boudreau
authors: National Center for Macromolecular Imaging, Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
authors: Ryan H
authors: RH
authors: Rochat
authors: National Center for Macromolecular Imaging, Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
authors: Michael F
authors: MF
authors: Schmid
authors: Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston, Houston, TX 77030, USA University of Texas at Houston Graduate School of Biomedical Sciences, Houston, TX 77030, USA Department of Nephrology, The First Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China.
authors: Yang
authors: Y
authors: Xia
authors: Department of Anatomy, University of California San Francisco, San Francisco, CA 94143, USA Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA wah@bcm.edu carolyn.larabell@ucsf.edu.
authors: Carolyn A
authors: CA
authors: Larabell
authors: National Center for Macromolecular Imaging, Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA wah@bcm.edu carolyn.larabell@ucsf.edu.
authors: Wah
authors: 0000-0002-8910-3078
authors: W
authors: Chiu
mesh_terms: D000755:Anemia, Sickle Cell / Q000201:enzymology*; D000818:Animals; D022081:Cell Surface Extensions / Q000187:drug effects / Q000378:metabolism; D004912:Erythrocytes / Q000187:drug effects / Q000201:enzymology*; D006801:Humans; D051379:Mice; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D014056:Tomography, X-Ray / Q000379:methods*; D000099157:Sphingosine Kinase
chemical_list: D017853:Phosphotransferases (Alcohol Group Acceptor); D047428:Protein Kinase Inhibitors; D000099157:Sphingosine Kinase
keywords: Cryogenic soft X-ray tomography; Red blood cell; Red cell morphology; Sickle cell disease; Sphingosine kinase inhibitor