title: Connexon-mediated cell adhesion drives microtissue self-assembly.
abstract: Microtissue self-assembly is thought to be driven primarily by cadherins, while connexons have been examined mainly in intercellular coupling. We investigated whether connexon 43 (Cx43)-mediated cell adhesion modulates self-assembly of human KGN granulosa cells, normal human fibroblasts (NHFs), and MCF-7 breast cancer cells seeded into nonadhesive agarose gels. We found that treatment with anti-Cx43 E2 (112 μg/ml), which suppresses Cx43 docking, significantly inhibited the kinetics of KGN and NHF self-assembly compared to the preimmune sera control (41.1 ± 4.5 and 24.5 ± 10.4% at 8 h, respectively). Likewise, gap junction inhibitor carbenoxolone also inhibited self-assembly of KGN, NHF, and MCF-7 cells in a dose-dependent manner that was specific to cell type. In contrast, Gap26 connexin mimetic peptide, which inhibits channel permeability but not docking, accelerated self-assembly of KGN and NHF microtissues. Experiments using selective enzymatic digestion of cell adhesion molecules and neutralizing N-cadherin antibodies further showed that self-assembly was comparably disrupted by inhibiting connexin- and cadherin-mediated adhesion. These findings demonstrate that connexon-mediated cell adhesion and intercellular communication differentially influence microtissue self-assembly, and that their contributions are comparable to those of cadherins.
authors.affiliation: Department of Molecular Pharmacology, Physiology, and Biotechnology, Center for Biomedical Engineering, Brown University, Providence, RI 02912, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Bao
authors.forename: Jean
authors.initials: J
authors.lastname: Jiang
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Yanase
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Nishi
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Morgan
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology / Q000494:pharmacology; D015153:Blotting, Western; D015820:Cadherins / Q000276:immunology / Q000378:metabolism; D002229:Carbenoxolone / Q000494:pharmacology; D002448:Cell Adhesion / Q000502:physiology; D002449:Cell Aggregation / Q000187:drug effects / Q000502:physiology; D002450:Cell Communication / Q000187:drug effects; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D018031:Connexin 43 / Q000276:immunology / Q000378:metabolism*; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D017629:Gap Junctions / Q000187:drug effects / Q000378:metabolism*; D019850:Heptanol / Q000494:pharmacology; D006801:Humans; D020100:Hydrogels; D007150:Immunohistochemistry; D008297:Male; D018613:Microscopy, Confocal; D018874:Spheroids, Cellular / Q000166:cytology; D013997:Time Factors
chemical_list: D000911:Antibodies, Monoclonal; D015820:Cadherins; D018031:Connexin 43; D020100:Hydrogels; D019850:Heptanol; D002229:Carbenoxolone