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Can anyone please advise on how to best measure colocalisation using
Leica?

I am looking at the colocalisation between a GFP labelled virus and
another
viral protein tagged with either Cy5 or Alexa 594 in axons of DRG
neurons.
The Leica TCS SPII system that I'm using allows me to calculate the
amount of
colocalisation between the two channels (GFP channel and either the Cy5
or
A594 channel) by using the Boolean operation called AND.  But I am not
sure
if this is an appropriate way of showing colocalisation because it uses
a
gray-scale, that is the "yellow" colocalising regions have different
shades
ranging from 0 to 255, so some regions are paler/darker than others.
I am also considering quantification of my data, by comparing the amount
of
colocalising pixels (using logical AND operator), versus the total
amount of
pixels (using logical OR operator).

Any advice on this subject will be greatly appreciated.

Regards,
Mary-Ann Lau
Honours student