{HEAD ~ The column} may then be inverted and irrigated internally with {TAIL ~ a wash buffer} to remove unhomogenized macroscopic tissue material and unbound residual cells 
irrigated internally with
{ HEAD ~ The column } may then be inverted and irrigated internally with { TAIL ~ a wash buffer } to remove unhomogenized macroscopic tissue material and unbound residual cells
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH