SPA17 Human
Description
Reproductive Role
SPA17 facilitates sperm-oocyte interaction by binding the zona pellucida, a glycoprotein layer surrounding oocytes . It exists as a homodimer on sperm heads and tails, enhancing adhesion during fertilization .
Pathological Roles
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Immune cell migration: Mediates intercellular adhesion, contributing to immune cell trafficking .
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Cancer metastasis: Promotes lymph node invasion via carbohydrate-binding motifs .
Role in Cancer
SPA17 is classified as a cancer-testis antigen (CTA), expressed in tumors but not in normal tissues (except testis and ciliated cells) .
Expression and Prognostic Significance
Immunological Insights
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Immune cell infiltration: SPA17 expression correlates with tumor-associated macrophages, Tregs, and CD8+ T cells .
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Immunotherapy response: High SPA17 levels predict anti-PD-L1 resistance in melanoma but response in urinary cancers .
Antibodies and Detection
The polyclonal antibody 13367-1-AP (Proteintech) targets SPA17 in:
| Application | Protocol | Source |
|---|---|---|
| Western blotting | Denaturing gels, 1:1000 dilution | |
| Immunohistochemistry | Paraffin-embedded sections |
Targeted Therapies
SPA17’s restricted normal tissue expression makes it a CTA candidate for immunotherapy :
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T-cell therapies: SPA17-specific cytotoxic T lymphocytes (CTLs) show promise in preclinical models .
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Biomarker for ICIs: SPA17 expression predicts response to anti-PD-1/PD-L1 in specific cancers .
Drugs and CMap Analysis
Connectivity Map (CMap) studies identified irinotecan and puromycin as SPA17-associated inhibitors, though mechanisms remain unclear .
Product Specs
Product Science Overview
SPA17 was first described as a rabbit sperm antigen with lectin-like properties . It is a major zona pellucida-binding protein, but its ubiquitous expression suggests a broader role in cell-cell adhesion and/or cell migration . The central portion of SPA17 contains carbohydrate-binding motifs, which likely contribute to its cell-cell adhesion functions .
SPA17 is a member of the cancer-testis antigen (CTA) family, which are proteins typically expressed in the testis but aberrantly expressed in various cancers . This unique expression pattern makes SPA17 a potential target for cancer immunotherapy. Studies have shown that SPA17 is highly expressed in endometrial and cervical cancers, among others . Its expression in these cancers is heterogeneous and not correlated with the histological subtype or grade of malignancy .
SPA17 has been proposed as a useful target for tumor-vaccine strategies and a novel marker to define tumor subsets and predict drug response . It has been found to regulate the progression of various cancers and is significantly correlated with immune-activated hallmarks, immune cell infiltrations, and immunoregulator expressions . This makes SPA17 a promising candidate for cancer immunotherapy and a potential prognostic marker .
Recombinant SPA17 is produced using recombinant DNA technology, which involves inserting the gene encoding SPA17 into a suitable expression system, such as bacteria or yeast, to produce the protein in large quantities. This recombinant protein can be used in various research applications, including studying its role in fertilization, cell adhesion, and cancer progression.
