A new feature of intercellular transfer observed in cultured sheep bone marrow mesenchymal stem cells

Abstract

Introduction: Intercellular communication governs the exchange of signalling molecules between cells. The different mechanisms employed in cell-to-cell communication include the secretion and receptor-mediated binding of diffusible messengers such as hormones and growth factors, the transport of small molecules through gap junctions, exosomes as well as tunnelling nanotubes. In this study, we report a new feature of intercellular transfer in cultured sheep bone marrow mesenchymal stem cells (BM-sMSCs). Methods: Bone marrow was harvested from iliac crest of healthy sheep. Mononuclear cells were isolated by gradient centrifugation, plated in culture flasks and incubated in the presence of Coon’s medium in a humidified atmosphere at 37 °C with 5% CO2. Non-adherent cells were discarded after 3 days and adherent cells were cultured until they reached near-confluence (10 days). The cells were trypsinized and the pellets were fixed with 3% glutaraldehyde and post-fixed in OsO4 1%. After dehydration and embedding in Epon 812, ultrathin sections were counterstained with lead citrate and uranyl acetate and observed at a transmission electron microscope. Results: The cell populations consisted of two undifferentiated cell types: electron-lucent and electron-dense cells. Both showed prominent RER, glycogen aggregates and filopodia. The electron-lucent cells were more numerous. The nucleus in electron-lucent cells was euchromatic and contained a prominent nucleolus, whereas in electron-dense cells it was irregular in shape and full of heterochromatin. No intercellular junctions were observed between either electron-lucent cells or electron-dense cells, whereas spot-like fusions of the plasma membrane occur between the electron-lucent cell surface and electron-dense cells. Across this distinct membranous connection, a flow of cytoplasm - but not of organules – occurs from electron-dense to electron-lucent cells. Conclusions: This finding shows a new cell-to-cell connection implicated in intercellular transfer and stimulates further studies to identify the cell types involved and the nature of the substances transferred.


Tutti gli autori

  • CROVACE A.;RESTA L.;DESANTIS S.

Titolo volume/Rivista

Non Disponibile


Anno di pubblicazione

2010

ISSN

0340-2096

ISBN

Non Disponibile


Numero di citazioni Wos

Nessuna citazione

Ultimo Aggiornamento Citazioni

Non Disponibile


Numero di citazioni Scopus

Non Disponibile

Ultimo Aggiornamento Citazioni

Non Disponibile


Settori ERC

Non Disponibile

Codici ASJC

Non Disponibile