Immunohistochemistry (IHC) is technique used in
histopathological laboratories. It is used to detect antigen by
specific antibodies in tissue sections. The theoretical part
deals with the basic concepts, explains the general procedure
with emphasis on critical points and describes various types of
methods and their standardization. Paraffin-embedded blocks,
which are the basic way of preserving tissues for the IHC
method, can be fixed with various fixatives. Most commonly used
fixatives are formalin or mixtures of alcohols, for example
methacarn. The practical part of the thesis therefore tests the
effect of fixation and length of storage on three types of
prenatal tissues using antibodies against CD 31, Ki-67, β-actin
and cyclin A. In the conditions of our experiment, the type of
used fixation and the length of storage did not prove as an
important factor capable to affect IHC's results. Therefore,
both fixatives could be used, even though formalin fixation
appears to be more suitable.