PTPN7 Antibody: Selection, Validation & Protocol Guide

PTPN7 Antibody is a research-grade immunoreagent designed to detect and study PTPN7 (Protein Tyrosine Phosphatase Non-Receptor Type 7), a key regulator of intracellular signaling cascades involved in immune cell function and MAP kinase pathway modulation.

Product SKU

Ab350665

Target Protein

PTPN7 (Protein Tyrosine Phosphatase Non-Receptor Type 7)

Formulation

PBS (Phosphate-Buffered Saline) only

Supplier Reference

absea #OC-1851

Recommended Storage

Store at -20°C; avoid repeated freeze-thaw cycles (textbook recommendation — verify with datasheet)

Protein Function

PTPN7 dephosphorylates tyrosine residues on target substrates, negatively regulating ERK1/2 and JNK MAP kinase signaling

What Is PTPN7 and Why Study It?

PTPN7, also known as HePTP (Hematopoietic Protein Tyrosine Phosphatase) or LC-PTP, is a non-receptor protein tyrosine phosphatase predominantly expressed in hematopoietic and immune cells. It plays a central role in negatively regulating T-cell and B-cell receptor signaling by dephosphorylating activation-loop tyrosines on ERK1/2 and JNK, thereby controlling the magnitude and duration of MAP kinase responses.

Dysregulation of PTPN7 activity has been implicated in inflammatory diseases and certain hematological malignancies, making it an important target for both basic immunology research and translational studies. Reliable antibody-based detection of PTPN7 protein expression, localization, and post-translational status is therefore critical for advancing these research programs.

Antibody Specifications and Formulation Considerations

Aladdin Scientific's PTPN7 Antibody (SKU: Ab350665, supplier reference absea #OC-1851) is supplied as a PBS-only formulation. This means the antibody is dissolved in phosphate-buffered saline without added stabilizers such as glycerol, BSA, or sodium azide preservative. Researchers should be aware of the following handling considerations associated with a PBS-only format:

• Short-term stability: PBS-only antibodies can be more susceptible to degradation during repeated freeze-thaw cycles. Aliquot upon receipt to minimize this risk.
• Preservative-free: The absence of sodium azide makes this formulation compatible with cell-based assays where azide may be cytotoxic, but also means microbial contamination is a greater concern — maintain aseptic technique.
• Carrier protein-free: If no BSA is present, the antibody is suitable for conjugation workflows and assays sensitive to exogenous proteins.
• Storage: Follow the manufacturer's datasheet recommendation. As a general best practice, store aliquots at -20°C for long-term storage and at 4°C for working stocks used within 1–2 weeks.

Note: Always consult the product datasheet for confirmed specifications including host species, clonality, isotype, and validated applications, as these details are subject to update.

Recommended Applications and Protocol Guidance

While specific validated applications for Ab350665 should be confirmed on the current product datasheet, PTPN7 antibodies of this class are commonly employed in the following techniques. Below are general protocol guidelines for each:

Western Blot (WB)

Lyse cells or tissue in RIPA or NP-40 lysis buffer supplemented with protease and phosphatase inhibitors. Resolve 20–40 µg total protein by SDS-PAGE and transfer to PVDF or nitrocellulose membrane. Block with 5% non-fat dry milk or 5% BSA in TBST for 1 hour at room temperature. Incubate with primary antibody at the manufacturer's recommended dilution (typically 1:500–1:2000) overnight at 4°C. Wash 3× with TBST, then incubate with appropriate HRP-conjugated secondary antibody for 1 hour at room temperature. Detect by ECL chemiluminescence. Expected band size for PTPN7 is approximately 38–40 kDa.

Immunofluorescence (IF) / Immunocytochemistry (ICC)

Fix cells with 4% paraformaldehyde for 15 minutes, permeabilize with 0.1–0.2% Triton X-100 in PBS for 10 minutes, and block with 5% normal serum. Incubate with primary antibody at the recommended dilution overnight at 4°C. Apply fluorophore-conjugated secondary antibody and counterstain nuclei with DAPI. PTPN7 is expected to show cytoplasmic localization.

Immunohistochemistry (IHC)

Perform antigen retrieval on formalin-fixed paraffin-embedded (FFPE) sections using citrate buffer (pH 6.0) or EDTA buffer (pH 9.0) as appropriate. Block endogenous peroxidase activity, apply primary antibody, and detect with a standard streptavidin-biotin or polymer HRP system.

Disclaimer: Confirm all application compatibility and optimal dilutions with the product datasheet before commencing experiments.

Troubleshooting Common Issues

When working with any antibody in a PBS-only formulation, researchers may encounter specific challenges. The following troubleshooting guide addresses the most frequent issues:

Problem	Likely Cause	Suggested Solution
No signal detected	Antibody degraded; incorrect dilution; incompatible antigen retrieval	Check antibody integrity by absorbance at 280 nm; optimize dilution with titration; test alternative antigen retrieval buffers
High background	Insufficient blocking; secondary antibody cross-reactivity; antibody concentration too high	Extend blocking time or switch blocking agent; increase wash steps; reduce primary antibody concentration
Multiple non-specific bands (WB)	Protease activity during lysis; antibody cross-reactivity	Ensure complete protease inhibition; include phosphatase inhibitors; consider running positive control lysate
Weak or inconsistent signal	Repeated freeze-thaw degradation; low target expression in chosen cell line	Aliquot antibody upon receipt; select cell lines or tissues with confirmed PTPN7 expression (e.g., hematopoietic lineage)

Storage, Handling, and Quality Assurance

Proper storage and handling of PTPN7 Antibody (Ab350665) are essential to maintain performance over time. As a PBS-only formulation, special attention to the following is recommended:

• Upon receipt: Inspect the vial for signs of leakage or precipitation. Centrifuge briefly if particles are visible. Aliquot into single-use volumes to prevent freeze-thaw degradation.
• Long-term storage: -20°C is recommended for long-term storage. For very long-term archiving (>12 months), -80°C may be preferable — confirm with the product datasheet.
• Working stock: Aliquots intended for immediate use may be kept at 4°C for up to 1–2 weeks. Do not leave antibody at room temperature for extended periods.
• Avoid: Repeated freeze-thaw cycles (limit to fewer than 5); exposure to light if fluorophore-conjugated; contamination with foreign proteins.
• Quality check: If signal loss or non-specific binding is observed after prolonged storage, run a dot-blot or ELISA with a known positive control to assess antibody activity before discarding a batch.

Aladdin Scientific recommends recording lot number, receipt date, and storage conditions for every antibody reagent to support experimental reproducibility and regulatory compliance where required.

Frequently asked questions

What formulation is the PTPN7 Antibody (Ab350665) supplied in?

PTPN7 Antibody (Ab350665) is supplied in PBS (phosphate-buffered saline) only, without added stabilizers such as glycerol, BSA, or sodium azide preservative. This makes it compatible with conjugation workflows and azide-sensitive cell-based assays, but requires careful aliquoting to prevent degradation from repeated freeze-thaw cycles.

What is the biological function of PTPN7 and why is it relevant to my research?

PTPN7 (also known as HePTP) is a hematopoietically expressed non-receptor protein tyrosine phosphatase that negatively regulates MAP kinase signaling by dephosphorylating ERK1/2 and JNK. It is predominantly expressed in immune cells and plays important roles in T-cell and B-cell receptor signal transduction. Research into PTPN7 is relevant to immunology, inflammatory disease, and hematological malignancy studies.

How should I store the PTPN7 Antibody to maintain its activity?

Upon receipt, aliquot the antibody into single-use volumes to avoid repeated freeze-thaw cycles. Store aliquots at -20°C for long-term use. Working aliquots can be kept at 4°C for 1–2 weeks. Always refer to the product datasheet for confirmed storage recommendations specific to this lot.

Which cell lines or tissues are appropriate positive controls for PTPN7 detection?

PTPN7 is predominantly expressed in hematopoietic and immune cell lineages. Hematopoietic cell lines (such as Jurkat T cells or other leukocyte-derived lines) or primary immune cell preparations are generally suitable positive controls. Confirm expression in your specific model system before use, and consult the product datasheet for any cell line recommendations provided by the manufacturer.

Can the PTPN7 Antibody be used for immunoprecipitation (IP) or flow cytometry (FC)?

Application compatibility depends on the specific clone and validation data for Ab350665. Not all antibodies validated for western blot are suitable for immunoprecipitation or flow cytometry, as these techniques require different epitope accessibility conditions. Please consult the Ab350665 product datasheet for the complete list of validated applications, and contact Aladdin Scientific technical support if your required application is not listed.

References

1. Saxena M, Williams S, Brockdorff J, Gilman J, Mustelin T. Inhibition of T cell signaling by mitogen-activated protein kinase-targeted hematopoietic tyrosine phosphatase (HePTP). Journal of Biological Chemistry. 1999;274(17):11693–11700.
2. Pettiford SM, Herbst R. The MAP-kinase ERK2 is a specific substrate of the protein tyrosine phosphatase HePTP. Oncogene. 2000;19(7):858–869.
3. Alonso A, Sasin J, Bottini N, et al. Protein tyrosine phosphatases in the human genome. Cell. 2004;117(6):699–711.

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.