HTRA4 Antibody
Description
Definition and Biological Context
HTRA4 is a member of the HtrA serine protease family, characterized by a catalytic trypsin-like domain and PDZ regulatory domains. It is predominantly expressed in placental trophoblasts and plays critical roles in:
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Placental development: Regulating trophoblast differentiation and syncytialization .
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Cancer progression: Modulating apoptosis, chemotherapeutic response, and metastasis .
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Endothelial dysfunction: Inhibiting endothelial progenitor cell (EPC) proliferation and repair .
HTRA4 antibodies target specific epitopes of the protein (e.g., catalytic domain, middle region) for applications such as Western blot (WB), ELISA, and immunohistochemistry (IHC) .
Antibody Targets and Mechanisms
HTRA4 antibodies have revealed that:
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Full-length HTRA4 and its N-terminal truncated form (∆N-HtrA4) enhance chemotherapeutic-induced apoptosis in cancer cells .
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HTRA4 suppresses endothelial cell proliferation by downregulating CDKN3, BIRC5, and MKI67 genes .
Experimental Use Cases
Disease Associations
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Preeclampsia: Elevated HTRA4 levels impair trophoblast syncytialization and endothelial repair, contributing to placental dysfunction .
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Cancer: HTRA4 is dysregulated in glioblastoma, breast, and prostate cancers, correlating with chemoresistance and poor prognosis .
Comparison of HTRA4 Antibodies
Key Validation Metrics
Recent Research Findings
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HTRA4 enhances cisplatin and etoposide efficacy in breast and lung cancer cells by degrading anti-apoptotic proteins .
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In preeclampsia, HTRA4 overexpression reduces β-hCG and syncytin-1, critical for placental syncytialization .
Challenges and Future Directions
Product Specs
Target Background
- Aberrant expression of HTRA1 or HTRA4 may be involved in the onset of preeclampsia, and increased expression of these proteins may affect trophoblast functions. PMID: 30015931
- GATA3 knockdown elevated HtrA4 expression in BeWo and JEG-3 trophoblast cell lines and enhanced the invasion activities of both lines. This study revealed a novel GATA3 function in the placenta as a negative regulator of GCM1 activity and trophoblastic invasion. PMID: 26899996
- HtrA4 is a novel placenta-specific serine protease that is specifically altered in early-onset preeclampsia, potentially playing a causal role in endothelial dysfunction and disease development. PMID: 25946029
- Conditioned media from decidualized cell lines suppress HtrA4-expressing JAR cell invasion in an HtrA1- or HtrA3-dependent manner. PMID: 25002585
- Data suggest that increased HtrA4 (and HtrA1) levels in placental tissues may be involved in the onset of pre-eclampsia. Elevated levels of HtrA4 (but not HtrA1) in serum have potential as a biomarker for pre-eclampsia. PMID: 22964307
- This study reveals a novel function of GCM1 and HtrA4 in regulating trophoblast invasion, suggesting that abnormal HrtA4 expression may contribute to shallow trophoblast invasion in preeclampsia. PMID: 22778138
- FLJ90724, also known as HTRA4, is a member of the HtrA family of proteases. PMID: 12408815
