VPAC2 receptor expression in human normal and neoplastic tissues: evaluation of the novel MAB SP235
Stefan Schulz1, Anika Mann2, Benjamin Novakhov2
1Institute of Pharmacology and ToxicologyJena University Hospital, Friedrich Schiller University Jena, Drackendorfer Straße 1, D-07747 Jena, GermanyFaculty of Life SciencesUniversity of Manchester, Manchester M13 9PT, UK Stefan.Schulz@med.uni-jena.de.
Abstract:
The vasoactive intestinal peptide receptor 2 (VPAC2) is widely distributed throughout the body and is also overexpressed in a variety of human neoplastic tissues. However, little is known about its precise tissue distribution, regulation and function, which is in part be due to the lack of specific monoclonal anti-VPAC2 antibodies. In this study, we extensively characterised the novel rabbit monoclonal anti-VPAC2 antibody (clone SP235) using transfected cells and mouse, rat and human tissues. SP235 was then subjected to a comparative immunohistochemical study on a series of 167 histological specimens from formalin-fixed, paraffin-embedded human tumours and adjacent normal tissues. SP235 detected a broad band migrating at a molecular weight of 50-70 kDa in western blotting analyses of various mouse tissues as well as VPAC2- but not VPAC1-transfected human embryonic kidney 293 cells. SP235 yielded an efficient immunostaining of distinct cell populations in human tissue samples with a predominance of plasma membrane staining, which was completely abolished by preadsorption with its immunising peptide. SP235 immunohistochemistry detected VPAC2 receptors in lymphocytes present in spleen, tonsils, lymph nodes and Peyer's patches, chief cells of gastric mucosa, exocrine and endocrine pancreas, kidney tubules and blood vessels. In addition, VPAC2 was observed in thyroid, gastric and lung carcinomas, pancreatic adenocarcinomas, sarcomas and neuroendocrine tumours. SP235 may prove of great value in the identification of VPAC2 receptors during routine histopathological examination. VPAC2 visualisation with this simple and rapid immunohistochemical method will facilitate identification of candidate tumours for vasoactive intestinal peptide (VIP)-based diagnostics or therapeutic interventions.
Insights
A new antibody, SP235, effectively detects vasoactive intestinal peptide receptor 2 (VPAC2) in various human tissues and tumors. This tool aids in identifying VPAC2 expression for potential VIP-based diagnostics and therapies.
Area of Science:
- Immunology
- Molecular Biology
- Oncology
Background:
- Vasoactive intestinal peptide receptor 2 (VPAC2) is found in many tissues and overexpressed in cancers, but its distribution and function are poorly understood.
- Lack of specific antibodies has limited research into VPAC2's precise roles.
- This study introduces a novel rabbit monoclonal antibody, SP235, for VPAC2 detection.
Purpose of the Study:
- To characterize the novel rabbit monoclonal anti-VPAC2 antibody (clone SP235).
- To determine the tissue distribution of VPAC2 in normal and neoplastic human tissues.
- To evaluate SP235's utility in histopathological examination for potential diagnostic and therapeutic applications.
Main Methods:
- Western blotting and immunohistochemistry were used to characterize SP235.
- Transfected cells and various mouse, rat, and human tissues were analyzed.
- A comparative study involved 167 human tumor and adjacent normal tissue specimens.
Main Results:
- SP235 detected VPAC2 at the expected molecular weight in western blots.
- Immunohistochemistry revealed VPAC2 in lymphocytes, gastric chief cells, pancreas, kidney tubules, and blood vessels.
- VPAC2 expression was confirmed in thyroid, gastric, lung, pancreatic, sarcoma, and neuroendocrine tumors.
Conclusions:
- The SP235 antibody is a valuable tool for detecting VPAC2 in various cell types and tissues.
- SP235 facilitates routine histopathological identification of VPAC2.
- This antibody can aid in identifying tumors for VIP-based diagnostic or therapeutic strategies.
