Mikael
I have not tried this lectin on brain but have used it on several other
tissues.
Some comments
1.    If using Bouin's you need to ensure that all the picric acid has been
removed from the section.
2.    "Processing in Bouin's" is a term that has many meanings and your
staining may vary considerably depending on the times and temperature in the
various solutions including the fixative.
3.    Have you used a control slide with competitive inhibitor such as
methyl-a- galactoside or p-nitrophenyl b-galactoside to test for what you
are demonstrating?
4.    GSI-B4 is an isolectin that shows a range of a-galactosyl groups and
so will show many different cells and also blood group B antigens.
5.    The purity of the isolectin and the conditions of use will greatly
influence the binding that you obtain. I know that the one from Vector labs
works well but if form other sources you need to ascertain its purity and
that it is indeed GSI-B4 that you are using and also strictly adhere to its
conditons of use.
Barry


Mikael Niku wrote:

> Hello!
>
> I have been trying to stain microglia in bovine brain
> sections using the GSA I-B4 lectin (Griffonia simplicifolia
> lectin I isolectin B4). This has been reported to work
> well for Bouin's or formalin fixed sections, also for
> bovine samples (e.g. Trautwein et al., Ann Anat 1996, 178:25-31).
>
> The problem is that I only get very beautiful endothelial
> staining, despite trying a few different fixatives and several different
> pretreatments. The endothelial staining is there whatever
> I do, but I can't see any microglial staining, or perhaps
> very weak and patchy at best.
>
> Any ideas? Or should I just try the next lectin?
>
> (If you're wondering why I'm so keen about lectins,
> it's just that I've spent quite a lot of time testing
> quite a few antibodies, and haven't found a suitable one).
>
> \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
>    Mikael Niku             URL: www.helsinki.fi/~mniku/
>    University of Helsinki  Dept. Basic Veterinary Sciences
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