This
is a monoclonal antibody to the A-subunit of human coagulation FactorXIII.
It recognizes human Factor XIII A-chain in both reduced and
non-reduced forms. It does not react with human Factor XIII B-chain or humanFactor XII. Factor XIII is a betaglobulin found in plasma
and is composed of two subunits. Factor XIII-A is the catalytic subunit and is
a dimer of M.W. 160,000. Factor XIII is present in plasma as an
alpha2beta2 heterodimer (M.W. 320,000); whereas in platelets, only the alpha2
unit exists. FactorXIIIa
is a dermal dendrocyte marker and shows variable reaction with these types of
tumors. It can be used for histiocytic phenotyping and has been reported to mark
capillary hemangiomas and tumors of the central nervous system. Factor XIIIa has also been used with CD34 to
differentiate between dermatofibroma and dermatofibrosarcoma
protuberans.