The DDOST antibody is a polyclonal rabbit-derived immunoglobulin (IgG) used to detect the DDOST protein, a non-catalytic subunit of the oligosaccharyltransferase (OST) complex. This complex is critical for N-linked glycosylation of nascent polypeptides in the endoplasmic reticulum. The antibody has applications in various biochemical assays, including Western blot (WB), immunohistochemistry (IHC), immunofluorescence (IF), immunoprecipitation (IP), co-immunoprecipitation (CoIP), and enzyme-linked immunosorbent assay (ELISA) .
| Parameter | Value |
|---|---|
| Host/Isotype | Rabbit/IgG |
| Reactivity | Human, mouse, rat |
| Conjugate | Unconjugated |
| Molecular Weight Target | 48 kDa (observed), 49 kDa (calculated) |
| Immunogen | DDOST fusion protein (Ag6727) |
| Purification Method | Antigen affinity purification |
| Storage Buffer | PBS with 0.02% sodium azide and 50% glycerol (pH 7.3) |
| Storage Conditions | -20°C (stable for 1 year) |
| Application | Dilution |
|---|---|
| Western Blot (WB) | 1:500–1:4000 |
| Immunoprecipitation (IP) | 0.5–4.0 µg per 1.0–3.0 mg of total protein lysate |
| Immunohistochemistry (IHC) | 1:50–1:500 (antigen retrieval with TE buffer pH 9.0 or citrate buffer pH 6.0) |
Gliomas: High DDOST expression correlates with poor prognosis in glioma patients, particularly in IDH-wild-type, 1p19q-non-codel, and MGMT-unmethylated subgroups. The antibody was used in IHC to confirm DDOST overexpression in high-grade gliomas .
Pancreatic Ductal Adenocarcinoma (PDAC): DDOST promotes oncogenesis by mitigating oxidative and ER stress, enabling tumor survival .
DDOST negatively correlates with tumor-infiltrating B cells and CD4+ T cells but positively associates with cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs). These findings suggest its role in creating an immunosuppressive microenvironment, limiting antitumor immune responses .
Congenital Disorder of Glycosylation (CDG): Mutations in DDOST are linked to CDG type Ir and In. A functional assay using DDOST antibodies confirmed pathogenic variants (e.g., p.S243F, p.E286del) that impair glycosylation .
The DDOST antibody is a valuable tool for studying glycosylation defects and tumor biology. Future research could explore:
Therapeutic Targeting: Inhibiting DDOST to disrupt glycosylation in aggressive cancers.
Biomarker Development: Validating DDOST as a prognostic marker in gliomas and PDAC.
Mechanistic Studies: Elucidating how DDOST modulates stress responses and immune evasion.
DDOST encodes a component of the oligosaccharide transferase (OST) complex and is involved in the N-glycosylation of proteins . Recent studies have demonstrated that DDOST is significantly upregulated in 27 out of 33 cancer types compared to normal tissues, including cervical cancer . Its expression has been linked to cancer development, progression, and poor prognosis across multiple cancer types. DDOST appears to play a role in tumor immunosuppressive microenvironments, making it an attractive target for understanding cancer biology and potential therapeutic development .
DDOST antibodies have been validated for several research applications:
| Application | Validated Dilution Range | Citations |
|---|---|---|
| Western Blot (WB) | 1:500-1:2000 | |
| Immunohistochemistry (IHC) | 1:100-1:200 | |
| Immunocytochemistry/Immunofluorescence (ICC-IF) | Validated |
Beyond basic protein detection, DDOST antibodies have been employed in studies examining immune cell infiltration patterns, tumor microenvironment analysis, and cancer prognosis assessment .
DDOST shows variable expression across tissue types. According to pan-cancer analyses:
Highest expression in cancer types: Testicular germ cell tumors (TGCT)
Lowest expression in cancer types: Kidney chromophobe (KICH)
When performing comparative studies, researchers should account for this baseline variability to accurately interpret results. In cervical cancer specifically, DDOST expression is significantly higher in tumor tissues compared to adjacent non-tumor tissues, as confirmed by immunohistochemistry .
For optimal IHC results with DDOST antibodies:
Tissue preparation: Use formalin-fixed, paraffin-embedded tissues sectioned at approximately 4 μm thickness .
Antigen retrieval: Perform microwave-based antigen retrieval after deparaffinization and rehydration in ethanol .
Antibody concentration: Begin with 1:500 dilution for rabbit polyclonal antibodies (e.g., Abcam ab204314) .
Incubation conditions: Incubate with primary antibody overnight at 4°C, followed by appropriate secondary antibody incubation for 45 minutes .
Controls: Always include both positive (high DDOST-expressing tissues like bone marrow) and negative controls to validate staining specificity .
Visualization: Standard DAB (3,3'-diaminobenzidine) protocols are effective for visualizing DDOST expression patterns .
Remember that optimization may be required based on your specific tissue type and fixation conditions.
Based on validated research approaches, multiple cervical cancer cell lines have been used successfully for DDOST studies:
Quantitative RT-PCR has confirmed that DDOST expression is higher in all cervical cancer cell lines compared to normal cervical epithelial cells (Ect1/E6E7), making these viable models for studying DDOST function in cervical cancer .
For accurate quantification of DDOST expression:
RNA level analysis: Quantitative real-time PCR has been successfully employed with appropriate housekeeping gene controls .
Protein level analysis:
Bioinformatic analysis: For public datasets, TCGA and GTEx databases provide reliable DDOST expression data across multiple cancer types and normal tissues .
When comparing expression levels between experimental groups, use statistical methods appropriate for your data distribution and sample size.
DDOST expression has significant correlations with immune cell infiltration patterns in the tumor microenvironment, particularly in cervical cancer:
Positive correlation: Regulatory T cells (Tregs) - immunosuppressive cells that can promote tumor progression
Negative correlation: CD8+ T cells and NK cells - cytotoxic immune cells that typically suppress tumors
When studying tumor samples with varying DDOST expression levels:
Use multi-parameter flow cytometry or multiplex immunohistochemistry to assess immune cell populations
Consider using ImmuCellAI database resources for complementary analysis
Compare high vs. low DDOST expression groups to identify differential immune infiltration patterns
This inverse relationship with cytotoxic immune cells suggests DDOST may contribute to an immunosuppressive microenvironment, potentially explaining its association with poor prognosis .
To investigate DDOST's relationship with drug sensitivity:
Database correlation analysis: Use the GDSC (Genomics of Drug Sensitivity in Cancer) database to correlate DDOST expression with IC50 values of various drugs .
Experimental validation approaches:
Generate DDOST knockdown or overexpression cell lines
Perform drug sensitivity assays with multiple concentrations
Calculate and compare IC50 values between modified and control cells
Research has identified several drugs whose efficacy correlates with DDOST expression:
| Drug Category | Positive Correlation with DDOST | Negative Correlation with DDOST |
|---|---|---|
| BCL-2 inhibitors | ABT737, WEHI-539, Sabutoclax | - |
| Platinum compounds | Cisplatin, Oxaliplatin | - |
| Nucleoside analogs | Gemcitabine | - |
| Kinase inhibitors | - | PF-4708671, KU-55933, Dasatinib, Trametinib |
Higher DDOST expression correlates with resistance to several standard chemotherapies but increased sensitivity to certain targeted therapies .
DDOST's role in cancer progression involves multiple pathways:
Glycosylation pathway involvement: As part of the OST complex, DDOST participates in N-glycosylation of proteins, potentially affecting receptor function and cellular signaling .
Cell cycle regulation: Research in hepatocellular carcinoma demonstrated that downregulation of DDOST reduced cell proliferation .
Immune microenvironment modulation: DDOST expression correlates with immunosuppressive patterns in multiple cancers:
Stress response pathways: DDOST appears connected to endoplasmic reticulum stress responses, with studies showing that suppression of related glycosylation components can trigger ER-stress-induced apoptosis via DDOST upregulation .
Research approaches should include pathway analysis tools, protein-protein interaction studies, and functional assays to further elucidate these mechanisms.
When working with DDOST antibodies, researchers may encounter several technical challenges:
Background signal in IHC/IF applications:
Specificity concerns:
Preservation issues:
When analyzing DDOST expression across cancer subtypes:
For rigorous validation of DDOST antibody specificity:
Positive tissue controls:
Negative controls:
Genetic manipulation controls:
DDOST knockdown/knockout cell lines or tissues
DDOST overexpression systems
Blocking peptide controls:
DDOST antibodies show potential for several translational applications:
Prognostic biomarker development:
Immunotherapy response prediction:
Drug resistance mechanisms:
Therapeutic target potential:
DDOST's role in multiple cancer types suggests it may be a viable therapeutic target
Future studies should explore the effects of DDOST inhibition on tumor growth and immune infiltration
For comprehensive cancer characterization, researchers should consider:
Multi-marker panels:
Integrated -omics approaches:
Correlate DDOST protein expression with transcriptomic and genomic data
Consider methylation status, as DDOST promoter methylation may affect expression
Spatial analysis technologies:
Use multiplex immunohistochemistry or imaging mass cytometry to analyze DDOST expression in spatial context with immune markers
This could reveal microanatomical relationships between DDOST-expressing cells and immune populations
Liquid biopsy integration:
Explore whether circulating tumor cells with high DDOST expression have distinctive properties
Investigate if DDOST can be detected in exosomes or other liquid biopsy components