Within the family of blood-group related
carbohydrate antigens the Thomsen-Friedenreich
(TF) antigen (or T antigen) is an outstanding member
by attracting scientific interest for more than 65
years and by having retained its significance as object
of current biomedical research; in particular, as a
pancarcinoma-associated antigen. In accordance with
its constant or even growing attraction scientists
have searched for specific reagents which would allow
the unambiguous and sensitive detection of the
Thomsen-Friedenreich antigen on cells or tissues.
While at the beginning, immunohistochemical work
on TF antigen expression was restricted by the
limited specificity of plant lectins (peanut lectin) a
significant progress has been possible since the
introduction of the hybridoma technique. The respective
monoclonal antibodies display distinct fine specificities
and cellular staining patterns in immunohistochemistry
and have contributed to controversia1 discussions on the
organ-characteristic and tumor-associated expression of
the TF antigen in some organs. It is the aim of this
survey to summarize in the context of its structural and
biosynthetic aspects the current knowledge on the tissue
expression of the TF antigen as based on the use of
peanut agglutinin and monoclonal antibodies and to
discuss the findings with regard to their biomedical
relevance, in particular, with emphasis on their value in
tumor diagnosis