Anti-ATR001 monoclonal antibody ameliorates atherosclerosis through beta-arrestin2 pathway

Biochem Biophys Res Commun. 2021 Mar 12:544:1-7. doi: 10.1016/j.bbrc.2021.01.054. Epub 2021 Jan 28.

Abstract

Background: Our previous study developed ATRQβ-001 vaccine, which targets peptide ATR001 from angiotensin Ⅱ (Ang Ⅱ) receptor type 1 (AT1R). The ATRQβ-001 vaccine could induce the production of anti-ATR001 monoclonal antibody (McAb-ATR) and inhibit atherosclerosis without feedback activation of the renin-angiotensin system (RAS). This study aims at investigating the underexploited mechanisms of McAb-ATR in ameliorating atherosclerosis.

Methods: AT1R-KO HEK293T cell lines were constructed to identify the specificity of McAb-ATR and key sites of ATRQβ-001 vaccine. Beta-arrestin1 knock-out (Arrb1-/-) mice, Beta-arrestin2 knock-out (Arrb2-/-) mice, and low-density lipoprotein receptor knock-out (LDLr-/-) mice were used to detect potential signaling pathways affected by McAb-ATR. The role of McAb-ATR in beta-arrestin and G proteins (Gq or Gi2/i3) signal transduction events was also investigated.

Results: McAb-ATR could specifically bind to the Phe182-His183-Tyr184 site of AT1R second extracellular loop (ECL2). The anti-atherosclerotic effect of McAb-ATR disappeared in LDLr-/- mice transplanted with Arrb2-/- mouse bone marrow (BM) and BM-derived macrophages (BMDMs) from Arrb2-/- mice. Furthermore, McAb-ATR inhibited beta-arrestin2-dependent extracellular signal regulated kinase1/2 (ERK1/2) phosphorylation, and promoted beta-arrestin2-mediated nuclear factor kappa B p65 (NFκB p65) inactivity. Compared with conventional AT1R blockers (ARBs), McAb-ATR did not inhibit Ang Ⅱ-induced uncoupling of heterotrimeric G proteins (Gq or Gi2/i3) and Gq-dependent intracellular Ca2+ release, nor cause RAS feedback activation.

Conclusions: Through regulating beta-arrestin2, McAb-ATR ameliorates atherosclerosis without affecting Gq or Gi2/i3 pathways. Due to high selectivity for AT1R and biased interaction with beta-arrestin2, McAb-ATR could serve as a novel strategy for treating atherosclerosis.

Keywords: Angiotensin Ⅱ receptor type 1; Atherosclerosis; Beta-arrestin; G protein; Monoclonal antibody.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Monoclonal / immunology
  • Antibodies, Monoclonal / pharmacology*
  • Atherosclerosis / immunology
  • Atherosclerosis / metabolism
  • Atherosclerosis / prevention & control*
  • Cells, Cultured
  • Disease Models, Animal
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Receptor, Angiotensin, Type 1 / chemistry
  • Receptor, Angiotensin, Type 1 / immunology*
  • Receptors, LDL / metabolism*
  • Vaccines, Virus-Like Particle / immunology
  • Vaccines, Virus-Like Particle / pharmacology*
  • beta-Arrestin 2 / metabolism*

Substances

  • ATRQbeta-001
  • Antibodies, Monoclonal
  • Receptor, Angiotensin, Type 1
  • Receptors, LDL
  • Vaccines, Virus-Like Particle
  • beta-Arrestin 2