TY - JOUR
T1 - Transition of podosomes into zipper-like structures in macrophage-derived multinucleated giant cells
AU - Balabiyev, Arnat
AU - Podolnikova, Nataly P.
AU - Mursalimov, Aibek
AU - Lowry, David
AU - Newbern, Jason M.
AU - Roberson, Robert W.
AU - Ugarova, Tatiana P.
N1 - Funding Information:
We thank James Faust for helpful advice on performing phase-contrast live-cell video experiments and Page Baluch for anti–ZO-1 antibodies. This work was supported by National Institutes of Health (NIH) grants HL63199 (T.P.U.) and R00NS076661 and R01NS097537 (J.M.N.). We acknowledge the use of facilities within the Eyring Materials Center at Arizona State University supported in part by (National Nanotechnology Coordinated Infrastructure-Electrical, Communications and Cyber Systems) NNCI-ECCS-1542160. Image data were collected using a Leica TCS SP5 LSCM (NIH SIG award S10 RR027154) and Leica TCS SP8 LSCM (NIH SIG award S10 OD023691) housed in the W.M. Keck Bioimaging Facility at Arizona State University.
PY - 2020/8/15
Y1 - 2020/8/15
N2 - Macrophage fusion resulting in the formation of multinucleated giant cells (MGCs) is a multistage process that requires many adhesion-dependent steps and involves the rearrangement of the actin cytoskeleton. The diversity of actin-based structures and their role in macrophage fusion is poorly understood. In this study, we revealed hitherto unrecognized actin-based zipper-like structures (ZLSs) that arise between MGCs formed on the surface of implanted biomaterials. We established an in vitro model for the induction of these structures in mouse macrophages undergoing IL-4-mediated fusion. Using this model, we show that over time MGCs develop cell-cell contacts containing ZLSs. Live-cell imaging using macrophages isolated from mRFP- or eGFP-LifeAct mice demonstrated that ZLSs are dynamic formations undergoing continuous assembly and disassembly and that podosomes are precursors of these structures. Immunostaining experiments showed that vinculin, talin, integrin αMβ2, and other components of podosomes are present in ZLSs. Macrophages deficient in WASp or Cdc42, two key molecules involved in actin core organization in podosomes, as well as cells treated with the inhibitors of the Arp2/3 complex, failed to form ZLSs. Furthermore, E-cadherin and nectin-2 were found between adjoining membranes, suggesting that the transition of podosomes into ZLSs is induced by bridging plasma membranes by junctional proteins.
AB - Macrophage fusion resulting in the formation of multinucleated giant cells (MGCs) is a multistage process that requires many adhesion-dependent steps and involves the rearrangement of the actin cytoskeleton. The diversity of actin-based structures and their role in macrophage fusion is poorly understood. In this study, we revealed hitherto unrecognized actin-based zipper-like structures (ZLSs) that arise between MGCs formed on the surface of implanted biomaterials. We established an in vitro model for the induction of these structures in mouse macrophages undergoing IL-4-mediated fusion. Using this model, we show that over time MGCs develop cell-cell contacts containing ZLSs. Live-cell imaging using macrophages isolated from mRFP- or eGFP-LifeAct mice demonstrated that ZLSs are dynamic formations undergoing continuous assembly and disassembly and that podosomes are precursors of these structures. Immunostaining experiments showed that vinculin, talin, integrin αMβ2, and other components of podosomes are present in ZLSs. Macrophages deficient in WASp or Cdc42, two key molecules involved in actin core organization in podosomes, as well as cells treated with the inhibitors of the Arp2/3 complex, failed to form ZLSs. Furthermore, E-cadherin and nectin-2 were found between adjoining membranes, suggesting that the transition of podosomes into ZLSs is induced by bridging plasma membranes by junctional proteins.
UR - http://www.scopus.com/inward/record.url?scp=85089607299&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85089607299&partnerID=8YFLogxK
U2 - 10.1091/mbc.E19-12-0707
DO - 10.1091/mbc.E19-12-0707
M3 - Article
C2 - 32579434
AN - SCOPUS:85089607299
VL - 31
SP - 2002
EP - 2020
JO - Molecular Biology of the Cell
JF - Molecular Biology of the Cell
SN - 1059-1524
IS - 18
ER -