IL-7 is expressed and secreted by human skeletal muscle cells.

  title={IL-7 is expressed and secreted by human skeletal muscle cells.},
  author={Fred Haugen and Frode Norheim and Henrik Lian and Andreas J. Wensaas and Svein Dueland and Ole Aleksander Berg and Ane Funderud and Bj{\o}rn S. Sk{\aa}lhegg and Truls Raastad and Christian A. Drevon},
  journal={American journal of physiology. Cell physiology},
  volume={298 4},
In addition to generating movement, skeletal muscle may have a function as a secretory organ. The aim of the present study was to identify novel proteins with signaling capabilities secreted from skeletal muscle cells. IL-7 was detected in media conditioned by primary cultures of human myotubes differentiated from satellite cells, and concentrations increased with incubation time. By immunoblotting and real-time RT-PCR IL-7 expression was confirmed at both protein and mRNA levels. Furthermore… 

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