STS14 Antibody
Description
Introduction to STS14 Antibody
STS14 antibodies are specialized immunological reagents developed for the detection of specific protein targets across different biological systems. Interestingly, the term "STS14" refers to distinct proteins in different contexts - primarily the Solanum tuberosum STS14 protein in plant biology and a synthetic polypeptide (sTs14) used in parasitology research related to Taenia solium infections. These antibodies are valuable tools for multiple laboratory applications including Western blotting, ELISA, and immunohistochemistry. This report carefully distinguishes between these contexts while providing comprehensive information about the antibodies developed against each target.
Plant STS14 Protein Characteristics
In the context of plant biology, STS14 refers to a protein expressed in Solanum tuberosum (potato). The STS14 protein has been identified as a member of the pathogenesis-related PR-1 protein family based on sequence similarity analyses . The protein is encoded by the sts14 gene, which produces highly expressed mRNA in potato pistils. According to molecular analysis, STS14 is specifically expressed throughout pistil development in both the stylar cortex and stigma tissues .
The deduced STS14 protein structure displays significant homology to pathogenesis-related proteins, suggesting its potential involvement in plant defense mechanisms . The protein is cataloged in the UniProt database with the accession number Q41495, providing a standardized reference point for researchers .
Expression and Function in Potato Biology
Research findings indicate that the sts14 gene is expressed specifically in pistil tissues of potato plants. Northern blot and in situ analyses have demonstrated consistent expression throughout pistil development in both the stylar cortex and stigma regions . The protein's structural similarity to pathogenesis-related PR-1 proteins suggests potential functional roles in:
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Protection of pollen tubes during their growth through the pistil
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Guidance of pollen tubes through the pistil tissues
The STS14 protein may participate in MYB gene family networks, which are known to play crucial roles in plant development and stress responses. The MYB gene family in potato has been extensively studied due to its importance in regulating plant growth, development, and responses to abiotic stressors .
Development and Characteristics
In parasitology research, "sTs14" refers to a synthetic polypeptide derived from Taenia solium cysticerci. This synthetic protein represents the full-length, mature protein of a 14-kDa antigen identified in the lentil lectin-bound fraction of cyst glycoproteins . The sTs14 polypeptide was developed as part of efforts to create simpler diagnostic assays for cysticercosis that could replace more labor-intensive methods.
The development of sTs14 involved:
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Isolation and purification of 14-kDa polypeptides from T. solium cysticerci
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Amino acid sequencing of these polypeptides
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Use of degenerate oligonucleotide primers corresponding to the amino acid sequences
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Amplification of cDNA clones from a T. solium cysticerci library
Diagnostic Applications and Performance
The sTs14 synthetic polypeptide has demonstrated significant utility as a diagnostic antigen for cysticercosis detection. Research has shown that sTs14 is recognized by antibodies in a majority of sera from patients with cysticercosis, while showing no cross-reactivity with sera from persons with other helminth infections or uninfected controls .
Recent advances in diagnostic methodologies have incorporated sTs14 into multiantigen print immunoassay (MAPIA) formats. A MAPIA using a combination of three antigens (rGP50 + rT24H + sTs14) has shown exceptional diagnostic performance for neurocysticercosis (NCC) :
| Specimen Type | Sensitivity | Sample Size |
|---|---|---|
| Parenchymal NCC | 97.5% | 40 patients |
| Subarachnoid NCC | 100% | 40 patients |
| Negative Controls | 98.53% specificity | 68 controls |
Table 2: Diagnostic performance of MAPIA using rGP50 + rT24H + sTs14 antigen combination
The optimal concentration of sTs14 in the MAPIA format was determined to be 3 ng/mm, based on careful optimization experiments balancing signal strength and background noise .
Competitive Binding and Epitope Analysis
Interestingly, research has uncovered unexpected interactions between sTs14 and other diagnostic antigens. Competitive ELISA experiments have demonstrated that sTs14 can compete with rT24H antigen in capturing antibodies, suggesting potential overlap in diagnostic epitopes despite no previous literature references to such overlap .
To investigate this phenomenon, researchers conducted:
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Competitive ELISA with different concentrations of sTs14 (0.25-10 µg/mL)
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Alignment and in silico modeling of antigens
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Prediction of linear (T) and conformational (B) epitopes
These analyses confirmed potential competitive binding between sTs14 and other antigens, with greater competition observed between sTsRS2var1 and rT24H due to shared linear epitope regions .
Distinguishing STS14 from ST14 (Suppression of Tumorigenicity 14)
It is important to distinguish STS14 antibodies from ST14 antibodies, which target a completely different protein. ST14, also known as Suppression of Tumorigenicity 14 or Matriptase, is a human gene product associated with colon carcinoma .
Unlike the plant STS14 protein or the parasitic sTs14 synthetic polypeptide, human ST14:
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Exhibits trypsin-like activity by cleaving synthetic substrates with Arg or Lys at the P1 site
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Is involved in the terminal differentiation of keratinocytes
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Functions in prostasin (PRSS8) activation and filaggrin (FLG) processing
ST14 antibodies are used extensively in cancer research and are available from multiple commercial sources with various technical specifications . The distinction between STS14 and ST14 antibodies is critical for researchers to avoid confusion and ensure proper experimental design and interpretation.
ELISA Applications
STS14 antibodies have been successfully employed in ELISA applications for both plant research and parasite detection. For plant-specific STS14 antibodies, ELISA has been validated for detecting the native protein in potato tissues .
In parasitology research, synthetic sTs14 was assessed for serologic potential using standard ELISA methodologies. The following findings were established:
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sTs14, unlike sTs18, demonstrated significant utility as a diagnostic antigen
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sTs14 was recognized by antibodies in most sera from cysticercosis patients
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No cross-reactivity was observed with sera from persons with other helminth infections
Additionally, competitive ELISA methodologies have been used to evaluate antibody binding competition between sTs14 and other diagnostic antigens. These experiments revealed that pre-incubation of sera with sTs14 reduced subsequent binding to rT24H-coated plates, confirming epitope competition .
Western Blotting Applications
Western blotting represents another validated application for STS14 antibodies. The plant-specific STS14 antibody has been verified for Western blot applications for detecting the protein in potato tissue extracts . This technique allows for size-based separation and identification of the target protein.
Interestingly, researchers have observed that polyclonal antibodies against sTs14 react with six discrete proteins present in the LLGP cyst fraction of T. solium. This finding suggests that TS14, the protein from which sTs14 is derived, may function as a subunit of larger, previously described antigens used in cysticercosis diagnostics .
Advanced Diagnostic Applications
The most significant recent advancement in sTs14 antibody application has been its incorporation into the Multiantigen Print Immunoassay (MAPIA) format for cysticercosis diagnostics. This methodology:
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Prints multiple antigens (including sTs14) as parallel lines on nitrocellulose membrane
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Cuts membrane into strips for individual patient testing
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Incubates strips with patient sera
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Detects bound antibodies with labeled secondary antibody
This approach has demonstrated exceptional sensitivity and specificity, particularly when sTs14 is combined with rGP50 and rT24H antigens, as shown in Table 2 above.
Future Research Directions
Research involving STS14 antibodies continues to evolve across both plant biology and parasitology fields. Several promising directions for future investigation include:
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In plant biology:
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In parasitology:
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In antibody technology:
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Development of monoclonal antibodies against specific STS14 epitopes
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Creation of recombinant antibody fragments for specialized applications
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Incorporation into multiplexed detection systems
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Product Specs
Constituents: 50% Glycerol, 0.01M Phosphate Buffered Saline (PBS), pH 7.4
Target Background
Q&A
What is STS14 and what role does it play in diagnostic applications?
STS14 (also known as sTS14) is a synthetic polypeptide that represents a full-length, mature protein originally identified from the lentil lectin-bound fraction of cyst glycoproteins from Taenia solium. It has demonstrated significant utility as a diagnostic antigen for cysticercosis, a tissue infection caused by the larval cysts of T. solium. Research has shown that sTS14 is recognized by antibodies in a majority of sera from patients with cysticercosis and notably shows no cross-reactivity with sera from individuals with other helminth infections or uninfected control subjects . The high specificity of this antigen makes STS14 antibodies particularly valuable in diagnostic applications where distinguishing between cysticercosis and other parasitic infections is critical.
What experimental methods are used to produce and validate STS14 antibodies?
When developing STS14 antibodies for research or diagnostic applications, several methodological approaches are employed:
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cDNA Cloning: The original development involved using degenerate oligonucleotide primers corresponding to amino acid sequences of 14- and 18-kDa polypeptides and a cDNA library prepared from T. solium cysticerci to amplify cDNA clones .
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Synthetic Polypeptide Production: Full-length, mature proteins can be synthesized based on the identified sequences.
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Validation Using ELISA: The serologic potential of synthetic polypeptides (like sTS14) is typically assessed using enzyme-linked immunosorbent assay (ELISA) with sera from confirmed cases of cysticercosis compared against control sera .
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Cross-reactivity Testing: Comprehensive validation includes testing against sera from individuals with other helminth infections to confirm specificity.
How do STS14 antibodies compete with other diagnostic targets in multiplex assays?
Research has revealed an unexpected competition between STS14 and other diagnostic antigens, particularly rT24H. Competitive ELISA experiments demonstrated that both 8 kDa antigens (sTs14 and sTsRS2) compete with rT24H, with sTsRS2 showing more pronounced competition than sTs14. Specifically, the ratio of response against sTs14 decreased from 12.22 to 3.18, while against sTsRS2 it decreased from 15.72 to 1.4 .
The competition mechanism has been further clarified through sequence alignments and in silico modeling. Local alignment identified conserved domains with approximately 60% similarities between rT24H and sTs14. More interestingly, prediction of linear epitopes T MHC-I and MHC-II for sTsRS2 showed higher scores in regions that are also present on the surface of rT24H antigen, suggesting the existence of common epitopes between these proteins .
This competitive binding has significant implications for multiplex assay design, where researchers must carefully select appropriate antigen combinations to avoid reduced sensitivity due to antibody competition.
What are the structural determinants of STS14 that contribute to its diagnostic utility?
The diagnostic utility of STS14 is closely linked to its molecular structure. Three-dimensional modeling and structural alignment studies have revealed that STS14 shares common alpha-helix structures with related antigens like rT24H and sTsRS2 . These structural similarities partially explain the competitive binding observed between these antigens.
The specificity of STS14 is attributed to unique epitope regions that are recognized by antibodies produced in cysticercosis patients but not by antibodies induced by other parasitic infections. This high specificity makes STS14 particularly valuable in diagnostic applications, especially when combined with other antigens to form a comprehensive diagnostic panel.
How does STS14 performance differ in various neurocysticercosis (NCC) presentations?
The performance of STS14-based diagnostics varies depending on the clinical presentation of neurocysticercosis:
| NCC Type | STS14 Detection Rate | Comments |
|---|---|---|
| Subarachnoid NCC | 100% | Part of optimized MAPIA with rGP50 and rT24H |
| Parenchymal NCC | 97.5% | May show weaker reactions in single lesion cases |
| Enhancing lesions | Lower detection | The only case not detected by optimized MAPIA was from a patient with parenchymal enhancing lesions |
This differential performance highlights the importance of considering the clinical manifestation of NCC when interpreting diagnostic results based on STS14 antibody detection .
What is the optimal antigen combination for diagnostic platforms incorporating STS14?
After rigorous optimization processes described in the literature, the combination of rGP50, rT24H, and sTs14 in a Multiantigen Print Immunoassay (MAPIA) has been shown to provide optimal diagnostic performance. This combination detected 100% of subarachnoid NCC cases and 97.5% of parenchymal cases, with only a single false positive reaction .
When designing diagnostic platforms, researchers should be aware that adding both sTs14 and sTsRS2 to the same strip may result in an additive competitive effect, potentially weakening or eliminating the response against rT24H. This observation guided researchers to select the combination of rGP50, rT24H, and sTs14 as the preferred antigen cocktail for diagnosis of NCC .
What protocols are recommended for optimizing STS14 antibody detection?
For optimal detection of STS14 antibodies, researchers should consider the following methodological approaches:
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Competitive ELISA Protocol:
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Sensitize ELISA plates with 1.5 μg/mL of competing antigen (e.g., rT24H) in carbonate-bicarbonate buffer
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Block with PBS-Tween 0.05% milk 5% solution
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Pre-incubate samples with different concentrations of sTs14 (0.25-10 μg/mL) under shaking at 37°C
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Add pre-incubated samples to ELISA plate and incubate for 1 hour at 37°C
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Wash five times with 1× PBS, pH 7.2 + 0.05% Tween-20
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Add secondary antibody (goat anti-Human IgG + HRP) at 1:7,500 dilution and incubate for 1 hour
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Develop using 3,3′,5,5′-tetramethylbenzidine (TMB) solution and read at 650 nm
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MAPIA Optimization:
When incorporating STS14 into MAPIA, researchers should test different antigen combinations that include at least one recombinant/synthetic antigen for each diagnostic protein family. The performance of each combination should be rigorously evaluated against well-characterized serum samples from different types of NCC presentations.
How can researchers validate the specificity of STS14-based diagnostic assays?
Validation of STS14-based diagnostic assays requires comprehensive testing against a range of serum samples:
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Positive Control Panels: Include sera from confirmed cases of different types of neurocysticercosis (subarachnoid, parenchymal, single lesion, multiple lesions)
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Negative Control Panels: Include:
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Sera from healthy individuals from both endemic and non-endemic regions
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Sera from patients with other helminth infections to assess cross-reactivity
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Sera from patients with other neurological conditions that may mimic NCC
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Statistical Analysis: Evaluate diagnostic power using metrics such as:
What is known about ST14/PRSS14 antibodies in cancer research?
While STS14 antibodies are primarily associated with cysticercosis diagnostics, it's important for researchers to note that ST14 (also known as PRSS14, matriptase, or membrane-type serine protease 1) has significant implications in cancer research. ST14/PRSS14 has been identified as a potential prognostic marker in breast cancer, particularly in estrogen receptor (ER) negative populations .
Survival analyses have shown that breast cancer patients with high ST14/Prss14 expression have significantly poorer outcomes in ER-negative populations. This relationship holds regardless of HER2 expression, though statistical significance can be limited by small sample sizes in some studies .
What are the molecular functions of ST14 that may be targeted by antibodies?
ST14 exhibits trypsin-like activity as defined by cleavage of synthetic substrates with Arg or Lys as the P1 site. It is involved in:
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Terminal differentiation of keratinocytes through prostasin (PRSS8) activation and filaggrin (FLG) processing
These functional roles suggest potential targets for antibody-based interventions beyond diagnostic applications, particularly in contexts like cancer research where modulating ST14 activity might have therapeutic implications.
What methodological considerations apply when working with ST14 antibodies in cell culture?
When working with ST14 antibodies in cell culture experiments, researchers should consider protocols similar to those used in related studies:
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Cell Culture Conditions: Human cell lines like retinal pigment epithelial cells transformed with telomerase (RPE-1) can be cultured in Dulbecco's Modified Eagle Medium (DMEM) containing 1 g/L glucose supplemented with penicillin, streptomycin, 1X non-essential amino acid cocktail, and 10% Fetal Bovine Serum .
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Transfection Protocols: For siRNA-transfections, seed 30,000–35,000 cells/mL overnight. Cells can receive 10 nM siRNA diluted in serum-free DMEM combined with 0.3% Interferin transfection reagent .
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Antibody Applications: Anti-ST14 antibodies can be used for western blotting and immunofluorescence at appropriate dilutions (typically 1:1000), following standard immunodetection protocols .
What improvements could enhance STS14 antibody-based diagnostics?
Several avenues for improving STS14 antibody-based diagnostics warrant further research:
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Epitope Refinement: Further characterization of the specific epitopes recognized by antibodies in patient sera could lead to more refined synthetic antigens with enhanced specificity.
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Point-of-Care Adaptations: Development of rapid, field-applicable tests incorporating STS14 could expand diagnostic accessibility in resource-limited settings where neurocysticercosis is endemic.
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Multiplex Optimization: Further investigation of antigen competition could lead to optimized multiplex platforms that maximize sensitivity across all included antigens.
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Quantitative Correlations: Research into correlations between antibody levels against STS14 and disease burden or prognosis could enhance the clinical utility of these diagnostic tools.
How might cross-platform integration of STS14 antibody detection improve diagnostic accuracy?
Integration of STS14 antibody detection across multiple diagnostic platforms offers potential for enhanced accuracy:
