Assessment of Protein Expression by Proximity Ligation Assay in the Nonhuman Primate Endometrium, Placenta, and Fetal Adrenal in Response to Estrogen

  • Thomas W. Bonagura
  • Jeffery S. Babischkin
  • Gerald J. Pepe
  • Eugene D. Albrecht
Part of the Methods in Molecular Biology book series (MIMB, volume 1366)


In the field of protein biology, immunology-based techniques have been evolving for detection and quantification of protein levels, protein-protein interaction, and protein modifications in cells and tissues. The proximity ligation assay (PLA), a method of detection that combines immunologic and PCR-based approaches, was developed to overcome some of the drawbacks that are inherent to other detection methods. The PLA allows for very sensitive and discretely quantifiable measures of unmodified, native protein levels, and protein-protein interaction/modification complexes in situ in both fixed tissues and cultured cells. We describe herein the PLA method and its applicability to quantify the effects of estrogen on expression of angioregulatory factors, e.g., angiopoietin-1 (Ang-1) in the endometrium, vascular endothelial growth factor (VEGF) in the placenta, and melanocortin 2 receptor (MC2R)/accessory protein (MRAP) in the fetal adrenal of the nonhuman primate.

Key words

Proximity ligation assay Immunocytochemistry Immunofluorescence Estrogen Endometrium Placenta Adrenal 



The authors appreciate the contributions of Dr. Graham Aberdeen in the collection of tissues used in this chapter. This work was supported by NIH Research Grants RO1 HD 13294 and RO1 DK 093950.


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Thomas W. Bonagura
    • 1
  • Jeffery S. Babischkin
    • 2
  • Gerald J. Pepe
    • 3
  • Eugene D. Albrecht
    • 2
  1. 1.Department of BiologyBuena Vista UniversityStorm LakeUSA
  2. 2.Departments of Obstetrics, Gynecology, Reproductive Sciences and Physiology, Center for Studies in ReproductionUniversity of Maryland School of MedicineBaltimoreUSA
  3. 3.Department of Physiological SciencesEastern Virginia Medical SchoolNorfolkUSA

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