Myosin II synergizes with F-actin to promote DNGR-1-dependent cross-presentation of dead cell-associated antigens
journal contributionposted on 2020-09-14, 10:07 authored by Oliver Schulz, Pavel Hanč, Jan P Böttcher, Robbert Hoogeboom, Sandra S Diebold, Pavel Tolar, Caetano Reis e Sousa
Conventional type 1 DCs (cDC1s) excel at cross-presentation of dead cell-associated antigens partly because they express DNGR-1, a receptor that recognizes exposed actin filaments on dead cells. In vitro polymerized F-actin can be used as a synthetic ligand for DNGR-1. However, cellular F-actin is decorated with actin-binding proteins, which could affect DNGR-1 recognition. Here, we demonstrate that myosin II, an F-actin-associated motor protein, greatly potentiates the binding of DNGR-1 to F-actin. Latex beads coated with F-actin and myosin II are taken up by DNGR-1+ cDC1s, and antigen associated with those beads is efficiently cross-presented to CD8+ T cells. Myosin II-deficient necrotic cells are impaired in their ability to stimulate DNGR-1 or to serve as substrates for cDC1 cross-presentation to CD8+ T cells. These results provide insights into the nature of the DNGR-1 ligand and have implications for understanding immune responses to cell-associated antigens and for vaccine design.
C-type lectinCLEC9ADNGR-1actinactin-binding proteinsdendritic cellsmyosin IIActinsAnimalsAntigensCell DeathCell LineCross-PrimingImmunizationLectins, C-TypeMelanoma, ExperimentalMice, Inbred C57BLMyosin Heavy ChainsMyosin Type IIPhagocytosisProtein BindingReceptors, ImmunologicT-Lymphocytes, CytotoxicReis e Sousa FC001136Tolar FC0011850601 Biochemistry and Cell Biology