how to define the structure of a GRID (WPF) in an xml file?

please I want to define the structure of a WPF control in xml.
And I want to do as follows in order to use XamlReader class:
<pre lang="HTML">
<MenuItem Tipo="C"  ContenidoGrid=" <Grid> cualquier contenido </Grid>" Estado="E"/>
</pre>
But in trying to process it, tells me to define it as:

<MenuItem Tipo="C"  ContenidoGrid=" &lt;Grid&gt; cualquier contenido &lt;/Grid&gt;" Estado="E"/>


And I do not want to do it this way because it would not be as readable for me, at the time of editing.
Is there any way to tell xml try everything in ContenidoGrid = ".." , treat it as a simple text and not be posting in special characters (<,>).

Or maybe there is a different kind of structure to xml maybe JSON