Chemically synthesized SDF-1alpha analogue, N33A, is a potent chemotactic agent for CXCR4/Fusin/LESTR-expressing human leukocytes.
Stromal cell-derived factor (SDF) 1 is a potent chemoattractant for leukocytes through activation of the receptor CXCR4/Fusin/LESTR, which is a fusion co-factor for the entry of T lymphocytotropic human immunodeficiency virus type 1 (HIV-1). This CXCR4-mediated HIV-1 fusion can be inhibited by SDF-1. Because of its importance in the study of immunity and AIDS, large scale production of SDF-1 is desirable. In addition to recombinant technology, chemical synthesis provides means by which biologically active proteins can be produced not only in large quantity but also with a variety of designed modifications. In this study, we investigated the binding and function of an SDF-1alpha analogue, N33A, synthesized by a newly developed native chemical ligation approach. Radioiodinated N33A showed high affinity binding to human monocytes, T lymphocytes, as well as neutrophils, and competed equally well with native recombinant SDF-1alpha for binding sites on leukocytes. N33A also showed equally potent chemoattractant activity as native recombinant SDF-1alpha for human leukocytes. Further study with CXCR4/Fusin/LESTR transfected HEK 293 cells showed that N33A binds and induces directional migration of these cells in vitro. These results demonstrate that the chemically synthesized SDF-1alpha analogue, N33A, which can be produced rapidly in large quantity, possesses the same capacity as native SDF-1alpha to activate CXCR4-expressing cells and will provide a valuable agent for research on the host immune response and AIDS.
Ueda
H
H
Laboratory of Molecular Immunoregulation, Division of Basic Sciences, Frederick, Maryland 21702, USA.
Siani
M A
MA
Gong
W
W
Thompson
D A
DA
Brown
G G
GG
Wang
J M
JM
D001667:Binding, Competitive; D054377:Chemokine CXCL12; D019743:Chemokines, CXC; D002634:Chemotaxis, Leukocyte / Q000187:drug effects*; D016207:Cytokines / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D007962:Leukocytes / Q000187:drug effects / Q000502:physiology*; D008565:Membrane Proteins / Q000096:biosynthesis / Q000502:physiology*; D009000:Monocytes / Q000187:drug effects / Q000502:physiology; D009504:Neutrophils / Q000187:drug effects / Q000502:physiology; D017354:Point Mutation; D019718:Receptors, CXCR4; D015728:Receptors, HIV / Q000096:biosynthesis / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology
C515255:CXCL12 protein, human; D054377:Chemokine CXCL12; D019743:Chemokines, CXC; D016207:Cytokines; D008565:Membrane Proteins; D019718:Receptors, CXCR4; D015728:Receptors, HIV; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins