Targeted inhibition of Axl receptor tyrosine kinase ameliorates anti-GBM-induced lupus-like nephritis

J Autoimmun. 2018 Sep:93:37-44. doi: 10.1016/j.jaut.2018.06.001. Epub 2018 Jun 9.

Abstract

Glomerulonephritis (GN) is a typical lesion in autoantibody and immune complex disorders, including SLE. Because the Gas6/Axl pathway has been implicated in the pathogenesis of many types of GN, targeting this pathway might ameliorate GN. Consequently, we have studied the efficacy and mechanism of R428, a potent selective Axl inhibitor, in the prevention of experimental anti-GBM nephritis. Axl upregulation was investigated with Sp1/3 siRNA in the SV40-transformed mesangial cells. For Axl inhibition, a daily dose of R428 (125 mg/kg) or vehicle was administered orally. GN was induced with anti-GBM sera. Renal disease development was followed by serial blood urine nitrogen (BUN) determinations and by evaluation of kidney histology at the time of sacrifice. Axl-associated signaling proteins were analyzed by Western blotting and inflammatory cytokine secretion was analyzed by Proteome array. SiRNA data revealed the transcription factor Sp1 to be an important regulator of mesangial Axl expression. Anti-GBM serum induced severe nephritis with azotemia, protein casts and necrotic cell death. R428 treatment diminished renal Axl expression and improved kidney function, with significantly decreased BUN and glomerular proliferation. R428 treatment inhibited Axl and significantly decreased Akt phosphorylation and renal inflammatory cytokine and chemokine expression; similar effects were observed in anti-GBM antiserum-treated Axl-KO mice. These studies support a role for Axl inhibition in glomerulonephritis.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Animals
  • Antibodies / administration & dosage
  • Axl Receptor Tyrosine Kinase
  • Benzocycloheptenes / pharmacology*
  • Cell Line, Transformed
  • Drug Administration Schedule
  • Gene Expression Regulation
  • Glomerular Basement Membrane / drug effects
  • Glomerular Basement Membrane / immunology
  • Immunologic Factors / pharmacology*
  • Intercellular Signaling Peptides and Proteins / genetics
  • Intercellular Signaling Peptides and Proteins / immunology
  • Lupus Nephritis / chemically induced
  • Lupus Nephritis / drug therapy*
  • Lupus Nephritis / genetics
  • Lupus Nephritis / immunology
  • Mesangial Cells / drug effects*
  • Mesangial Cells / immunology
  • Mesangial Cells / pathology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Molecular Targeted Therapy / methods*
  • Protein Kinase Inhibitors / pharmacology*
  • Proto-Oncogene Proteins / antagonists & inhibitors
  • Proto-Oncogene Proteins / genetics*
  • Proto-Oncogene Proteins / immunology
  • Proto-Oncogene Proteins c-akt / genetics
  • Proto-Oncogene Proteins c-akt / immunology
  • RNA, Small Interfering / genetics
  • RNA, Small Interfering / metabolism
  • Receptor Protein-Tyrosine Kinases / antagonists & inhibitors
  • Receptor Protein-Tyrosine Kinases / genetics*
  • Receptor Protein-Tyrosine Kinases / immunology
  • Signal Transduction
  • Sp1 Transcription Factor / antagonists & inhibitors
  • Sp1 Transcription Factor / genetics
  • Sp1 Transcription Factor / immunology
  • Sp3 Transcription Factor / antagonists & inhibitors
  • Sp3 Transcription Factor / genetics
  • Sp3 Transcription Factor / immunology
  • Triazoles / pharmacology*

Substances

  • Antibodies
  • Benzocycloheptenes
  • Immunologic Factors
  • Intercellular Signaling Peptides and Proteins
  • Protein Kinase Inhibitors
  • Proto-Oncogene Proteins
  • RNA, Small Interfering
  • Sp1 Transcription Factor
  • Sp3 protein, mouse
  • Triazoles
  • growth arrest-specific protein 6
  • bemcentinib
  • Sp3 Transcription Factor
  • Receptor Protein-Tyrosine Kinases
  • Proto-Oncogene Proteins c-akt
  • Axl Receptor Tyrosine Kinase
  • AXL receptor tyrosine kinase, mouse