Cellular expression of CD26/dipeptidyl peptidase IV

Area of Science:

• Immunology
• Biochemistry
• Cell Biology

Background:

• Dipeptidyl peptidase 4 (DPP4), also identified as lymphocyte cell surface protein CD26, is a serine protease.
• DPP4 deactivates hormones and cytokines by cleaving N-terminal dipeptides, playing roles in membrane digestion and binding bioactive molecules.
• The soluble form of DPP4 is found in various body fluids, and its broad distribution suggests diverse cellular functions.

Purpose of the Study:

• To review the cellular distribution of CD26/DPP4, including subcellular localization and pathological changes.
• To highlight the importance of precise localization data for understanding DPP4's functional significance.
• To discuss the implications for clinical applications in disease diagnosis and treatment.

Main Methods:

• Summary of immunohistochemical findings on CD26/DPP4 distribution.
• Comparison of immunohistochemistry with enzyme histochemistry for cellular localization studies.
• Consideration of factors affecting immunohistochemical results, such as animal species, tissue types, and antibody specificity.

Main Results:

• Immunohistochemistry provides higher specificity and is easier to use at electron microscopic levels compared to enzyme histochemistry.
• Immunoreaction in immunohistochemical analyses is influenced by animal species, tissue sections, and antibody specificity.
• The review synthesizes existing immunohistochemical data on CD26/DPP4 localization.

Conclusions:

• Precise information on CD26/DPP4 cellular and subcellular distribution is crucial for understanding its diverse roles.
• Accurate localization data aids in advancing the clinical use of DPP4 in disease diagnosis and treatment.
• Immunohistochemistry is a key method for examining CD26/DPP4 distribution, despite potential variations in results.