beta-gal senescence staining of mouse tissue

[corona]

> Hi,
>
> I am planning to do immunohistochemistry with embryonic / adult KO
> mouse tissue to look for signs of senescence  by X-Gal staining (kit
> from Cell Signaling Tech). Do you think these tissue should be
> formalin/paraffin embeded or snap frozen?

The tissue should be fixed in formaldehye and embedded in parafin wax rather 
than snapped frozen prior to sectioning. Snapped frozen tissue gives reduced 
sensitivity, but is useful for fixing tissue rapidly (would not apply to 
you).

>Also can these tissues be collected for a couple of weeks and then stained?

You could fix the tissue first and then store them for a couple of weeks.