PAEP Antibodies

Background

The glycoprotein encoded by the PAEP gene (also known as Glycodelin) belongs to the lipid transport protein family and is mainly expressed in reproductive tissues such as the endometrium and mammalian mammary glands. This protein plays a crucial regulatory role in reproductive processes such as embryo implantation, immune privilege, and sperm-egg recognition through tissue-specific glycosylation modification. Studies have shown that PAEP is abnormally expressed in endometrial cancer and melanoma, and participates in tumor immune escape by inhibiting T cell activation. Its genetic polymorphism is significantly correlated with dairy cow milk production traits and sow reproductive performance. This gene was originally named after the progesterone-related endometrial protein. The structural analysis of this gene provides an important model for understanding the ligand binding mechanism of the lipid transport protein family and reproductive immune regulation.

Structure Function Application Advantage Our Products

Structure of PAEP

The glycoprotein encoded by the PAEP gene has a molecular weight of approximately 28 kDa. The core peptide chain of this protein consists of 180 amino acids and varies among different species. This protein belongs to the lipid transport protein family and has a typical β-barrel three-dimensional structure, forming a hydrophobic ligand binding pocket.

Species	Human	Cow	Pig	Mouse
Molecular Weight (kDa)	28	24	25	26
Primary Structural Differences	Contains 3 glycosylation sites	Main component of whey protein	High sequence similarity	Different glycosylation patterns

The functions of glycoproteins are highly dependent on their tissue-specific glycosylation modifications. Different sugar chain structures confer diverse biological functions on them in reproductive immunity, embryo implantation, and tumor occurrence.

Fig. 1 Identification and Localization of Nine PAEP Gene Single Nucleotide Polymorphisms.¹

The key structural features of the protein encoded by the PAEP gene:

The typical β-barrel structure, which forms a hydrophobic ligand-binding pocket
Three conserved disulfide bonds stabilize the three-dimensional conformation of the protein.
Tissue-specific N-glycosylation sites determine the reproductive immune regulatory function.
The surface loop region is variable and affects the specificity of ligand recognition.

Functions of PAEP

The glycoprotein encoded by the PAEP gene plays multiple regulatory roles in the reproductive system, and its biological effects are tissue-specific.

Function	Description
Immune Regulation	Inhibits T-cell activation at the maternal-fetal interface, induces immune tolerance, and protects the embryo from maternal immune system attack.
Endometrial Remodeling	Participates in the differentiation of the endometrium during the secretory phase, regulates endometrial receptivity, and creates an appropriate microenvironment for embryo implantation.
Sperm Selection	Interacts with sperm surface glycoproteins, affects the ability of sperm to penetrate the oocyte cumulus, and participates in fertilization regulation.
Breast Secretion	As a component of whey protein (β-casein), participates in the provision of nutrients for the newborn offspring.

The function of PAEP is highly dependent on its tissue-specific glycosylation modification. Different sugar chain structures confer diverse biological activities to this protein, and its expression is regulated by hormones such as progesterone.

Applications of PAEP and PAEP Antibody in Literature

1. Kolenda, Magdalena, et al. "Composite genotypes of progestogen-associated endometrial protein gene and their association with composition and quality of dairy cattle milk." Animal Bioscience 34.8 (2021): 1283. https://doi.org/10.5713/ab.20.0596

The article indicates that the PAEP gene encodes whey protein. This study analyzed the polymorphism of this gene in 782 dairy cows. The results revealed 3 polymorphic SNPs, resulting in 5 genotypes, which significantly affected milk yield, milk composition and somatic cell count. These can be used as molecular markers for optimizing breeding plans.

2. Zhao, Yong, et al. "Association analysis of PAEP, KRT10, and BMP 7 genes SNPs with reproductive traits in Kele pigs." Plos one 20.7 (2025): e0311064. https://doi.org/10.1371/journal.pone.0311064

In this study, 9 SNPs were detected in the cola pig PAEP, KRT10 and BMP7 genes. Among them, the missense mutation in the PAEP gene affected the structure of mRNA and protein. The specific genotypes (CC, AA) of the PAEP gene were significantly superior to other genotypes in reproductive traits, and could be used as potential molecular markers for improving the reproductive performance of sows.

3. Ren, Suping, et al. "Human malignant melanoma-derived progestagen-associated endometrial protein immunosuppresses T lymphocytes in vitro." PLoS One 10.3 (2015): e0119038. https://doi.org/10.1371/journal.pone.0119038

The study found that PAEP is highly expressed in melanoma, and the protein it secretes can inhibit the secretion of IL-2 and IFN-γ by CD4+ T cells, as well as suppress lymphocyte proliferation and cytotoxic activity, and promote apoptosis. This indicates that tumor-derived PAEP participates in melanoma immune escape by inducing T-cell immunosuppression.

4. Pearson-Farr, Jennifer E., et al. "Endometrial gland-specific progestagen-associated endometrial protein and cilia gene splicing changes in recurrent pregnancy loss." Reproduction and Fertility 3.3 (2022): 162-172. https://doi.org/10.1530/RAF-22-0002

The study found that there were gene transcription and splicing alterations in the endometrial glands of women with recurrent miscarriage, including changes in the subtypes and exon usage of key genes GALNT11 and PAEP. These endometrial gland markers can be used to identify endometrial dysfunction, providing a basis for elucidating the mechanism of recurrent miscarriage and targeted treatment.

5. Hautala, Laura C., et al. "Altered glycosylation of glycodelin in endometrial carcinoma." Laboratory Investigation 100.7 (2020): 1014-1025. https://doi.org/10.1038/s41374-020-0411-x

The research found that the glycoproteins expressed by endometrial cancer cells (encoded by the PAEP gene) are different from those of normal endometrium in terms of glycosylation. They show a decreased sialylation level and an increased poly-LacNAc structure. Based on this, the in situ detection method of UEAI lectins established can specifically identify cancer-related glycoproteins, providing a new tool for the diagnosis of endometrial cancer.

Creative Biolabs: PAEP Antibodies for Research

Creative Biolabs specializes in the production of high-quality PAEP antibodies for research and industrial applications. Our portfolio includes monoclonal and polyclonal antibodies tailored for ELISA, Flow Cytometry, Western blot, immunohistochemistry, and other diagnostic methodologies.

Custom PAEP Antibody Development: Tailor-made solutions to meet specific research requirements.
Bulk Production: Large-scale antibody manufacturing for industry partners.
Technical Support: Expert consultation for protocol optimization and troubleshooting.
Aliquoting Services: Conveniently sized aliquots for long-term storage and consistent experimental outcomes.

For more details on our PAEP antibodies, custom preparations, or technical support, contact us at email.

Reference

Kolenda, Magdalena, et al. "Composite genotypes of progestogen-associated endometrial protein gene and their association with composition and quality of dairy cattle milk." Animal Bioscience 34.8 (2021): 1283. Distributed under Open Access license CC BY 4.0, without modification. https://doi.org/10.5713/ab.20.0596