How to combine a cell array of cell arrays to a single cell array in MATLAB

I have a dynamic cell array of cell arrays (of strings) and I want to combine it into a single cell array of strings.

Example:

Columns 1 through 4
{4x1 cell}    {9x1 cell}    {8x1 cell}    {10x1 cell} 

I want to concatenate the inner cells, and the result be one cell array of the form

{31x1 cell}.

How can I concatenate into one cell array without for loop?

Thanks