<<Disclaimer: Verify this information before applying it to your situation.>>

According to Scott Adam's often reffered to site at
http://celiac.com/forbiden.html :

      Cellulose is a carbohydrate polymer of D-glucose.  It is the
      structural material of plants, such as wood in trees.
      It contains no gluten protein.

This statement has also been echoed many times on this listserver and
Sprue-nik Press.

Best Health

Greg Funaro (GF in Huntsville, AL)