Decoy receptor 3 (DcR3) is proteolytically processed to a metabolic fragment having differential activities against Fas ligand and LIGHT.
Fas ligand (FasL) and Fas receptor are members of the tumor necrosis factor (TNF) receptor and ligand family that play an important role in regulating apoptosis in normal physiology. Decoy receptor 3 (DcR3) is a novel member of the TNF receptor superfamily, which binds to and blocks the activities of the ligands FasL and LIGHT. We have demonstrated that DcR3 was degraded rapidly to a major circulating metabolic fragment after subcutaneous administration in primates and mice. This fragment was also generated in subcutaneous tissue homogenate in vitro. Mass spectrometry and N-terminal sequencing indicated that DcR3 was proteolytically cleaved between R218 and A219 in the primary sequence to yield the fragment DcR3(1-218). While retaining its ability to bind LIGHT and inhibit LIGHT-mediated activities, DcR3(1-218) no longer bound FasL and did not inhibit FasL-mediated apoptosis in vitro. The primary sequence of DcR3 was molecularly engineered, changing the arginine residue at position 218 to glutamine to generate an analog, DcR3(R218Q), which we termed FLINT (LY498919). We demonstrated that FLINT was more stable to proteolytic degradation in vitro and in vivo and maintained its activity against both soluble FasL and soluble LIGHT in vitro. As a result, the modification in the sequence of DcR3 to produce FLINT (LY498919) should result in a pharmacologically superior molecule in the therapeutic intervention of diseases in which the pathogenesis is linked to FasL-mediated apoptotic or inflammatory events.
Wroblewski
Victor J
VJ
Department of Drug Disposition Development/Commercialization, Lilly Research Laboratories, Lilly Corporate Center, Indianapolis, IN 46285, USA. wroblewski_victor@lilly.com
Witcher
Derrick R
DR
Becker
Gerald W
GW
Davis
Kelly A
KA
Dou
Shenshen
S
Micanovic
Radmila
R
Newton
Christy M
CM
Noblitt
Timothy W
TW
Richardson
John M
JM
Song
Ho Yeong
HY
Hale
John E
JE
D000818:Animals; D053222:Fas Ligand Protein; D006801:Humans; D019169:Jurkat Cells; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism* / Q000494:pharmacology; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D010446:Peptide Fragments / Q000494:pharmacology; D010447:Peptide Hydrolases / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism*; D018124:Receptors, Tumor Necrosis Factor; D053323:Receptors, Tumor Necrosis Factor, Member 6b; D053326:Tumor Necrosis Factor Ligand Superfamily Member 14; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
C505661:FASLG protein, human; D053222:Fas Ligand Protein; C505658:Fasl protein, mouse; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D010446:Peptide Fragments; D011956:Receptors, Cell Surface; D018124:Receptors, Tumor Necrosis Factor; D053323:Receptors, Tumor Necrosis Factor, Member 6b; C505911:TNFRSF6B protein, human; C505914:TNFSF14 protein, human; C505915:Tnfsf14 protein, mouse; D053326:Tumor Necrosis Factor Ligand Superfamily Member 14; D014409:Tumor Necrosis Factor-alpha; D010447:Peptide Hydrolases