Human mesenchymal stem cells make cardiac connexins and form functional gap junctions

Authors

  • Virginijus Valiunas,

    1. Department of Physiology and Biophysics, Institute of Molecular Cardiology, State University of New York at Stony Brook, Stony Brook, NY 11794, USA
    Search for more papers by this author
  • Sergey Doronin,

    1. Department of Physiology and Biophysics, Institute of Molecular Cardiology, State University of New York at Stony Brook, Stony Brook, NY 11794, USA
    Search for more papers by this author
  • Laima Valiuniene,

    1. Department of Physiology and Biophysics, Institute of Molecular Cardiology, State University of New York at Stony Brook, Stony Brook, NY 11794, USA
    Search for more papers by this author
  • Irina Potapova,

    1. Department of Physiology and Biophysics, Institute of Molecular Cardiology, State University of New York at Stony Brook, Stony Brook, NY 11794, USA
    Search for more papers by this author
  • Joan Zuckerman,

    1. Department of Physiology and Biophysics, Institute of Molecular Cardiology, State University of New York at Stony Brook, Stony Brook, NY 11794, USA
    Search for more papers by this author
  • Benjamin Walcott,

    1. Department of Physiology and Biophysics, Institute of Molecular Cardiology, State University of New York at Stony Brook, Stony Brook, NY 11794, USA
    Search for more papers by this author
  • Richard B. Robinson,

    1. Department of Pharmacology, Center for Molecular Therapeutics, Columbia University, New York, NY 10032, USA
    Search for more papers by this author
  • Michael R. Rosen,

    1. Department of Pharmacology, Center for Molecular Therapeutics, Columbia University, New York, NY 10032, USA
    Search for more papers by this author
  • Peter R. Brink,

    1. Department of Physiology and Biophysics, Institute of Molecular Cardiology, State University of New York at Stony Brook, Stony Brook, NY 11794, USA
    Search for more papers by this author
  • Ira S. Cohen

    1. Department of Physiology and Biophysics, Institute of Molecular Cardiology, State University of New York at Stony Brook, Stony Brook, NY 11794, USA
    Search for more papers by this author

Corresponding author I. S. Cohen: Department of Physiology and Biophysics, 8661 SUNY, Stony Brook, NY 11794-8661, USA. Email: icohen@physiology.pnb.sunysb.edu

Abstract

Human mesenchymal stem cells (hMSCs) are a multipotent cell population with the potential to be a cellular repair or delivery system provided that they communicate with target cells such as cardiac myocytes via gap junctions. Immunostaining revealed typical punctate staining for Cx43 and Cx40 along regions of intimate cell-to-cell contact between hMSCs. The staining patterns for Cx45 rather were typified by granular cytoplasmic staining. hMSCs exhibited cell-to-cell coupling to each other, to HeLa cells transfected with Cx40, Cx43 and Cx45 and to acutely isolated canine ventricular myocytes. The junctional currents (Ij) recorded between hMSC pairs exhibited quasi-symmetrical and asymmetrical voltage (Vj) dependence. Ij records from hMSC–HeLaCx43 and hMSC–HeLaCx40 cell pairs also showed symmetrical and asymmetrical Vj dependence, while hMSC–HeLaCx45 pairs always produced asymmetrical Ij with pronounced Vj gating when the Cx45 side was negative. Symmetrical Ij suggests that the dominant functional channel is homotypic, while the asymmetrical Ij suggests the activity of another channel type (heterotypic, heteromeric or both). The hMSCs exhibited a spectrum of single channels with transition conductances (γj) of 30–80pS. The macroscopic Ij obtained from hMSC–cardiac myocyte cell pairs exhibited asymmetrical Vj dependence, while single channel events revealed γj of the size range 40–100pS. hMSC coupling via gap junctions to other cell types provides the basis for considering them as a therapeutic repair or cellular delivery system to syncytia such as the myocardium.

Ancillary