Hi everyone,
We are immunostaining for
macrophages and dendritic cells.
and have encountered what appears to be endogenous biotin as avidin
conjugates alone seemed to stain tissue.  Has anyone encountered this
problem before and are they aware of
any techniques that block endogenous biotin in tissue prior to staining?
 
 
There is commercially available a blocking kit for endogenous biotin:
Avidin/biotin Blocking Kit, Vector Laboratories, SP-2001.
In some cases it helps.
You may also try streptavidin, instead of avidin, since they say that
streptavidin has lower affinity for biotin in eukaryotic cells.
Riitta Miettinen, Ph.D.
Dept. of Neurology
Univ. of Kuopio
P.O. Box 1627
FIN-70211
FINLAND
E-mail: [log in to unmask]
Tel: 358-71-162761
Fax: 358-71-162048