What Can Immunocytochemistry Tell Us

Immunocytochemistry harnesses antibodies that are specific reagents and which allow unique detection of proteins and molecules. Using antibodies requires specific methods, labels, and controls. Performing immunocytochemistry experiments requires some basic knowledge of biology. 

Morphological approaches in biomedical research can include a wide range of microscopes, but today typically employ immunocytochemistry that can give us information about individual liver cells containing the specific enzyme. Immunocytochemistry uses antibodies to bind proteins and labels to show protein s location. If, for example, the enzyme is a marker for inflammation, then the location of cells with this enzyme tells us which cell types have the inflammatory response. Thus, immunocytochemistry methods are broadly defined as individual studies of single cells or cell groups. The resulting data tell us about location of the enzyme. 

To look at how immunocytochemistry (an individual study) has advantages over an enzyme assay (a population study), let us compare the types of results from these two approaches. To determine the enzyme level, the liver is ground up and a specific biochemical enzyme assay is performed (Fig. 1.1a). At different time points, the level of enzyme activity increases significantly as seen by the small errors shown on the graph (Fig. 1.1a). However, it is easy to assume that all cells in the liver have the enzyme (Fig. 1.1b) detected in the biochemical assay. In reality, however, the 

Biochemical assay from whole liver for enzyme activity 

To explore the possibility that only a subpopulation of liver cells has the enzyme immunocytochemistry, an individual study is performed. Results could show one of several patterns of distribution for the enzyme. The enzyme could be found in one cell type in the liver (Fig. 1.1c). But more realistic scenario is that the enzyme is found only in few cells of a specific cell type due to local injury (Fig. l.ld). If injury is causing the enzyme activity, then most likely that expression of the enzyme will be seen in several cell types near the injury site (Fig. Lie). Thus, immunocytochemistry gives us valuable information about the location and number of cells expressing the enzyme. The important point here is that biochemical and immunocytochemistry data are complementary neither can replace the other. 

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