Human IL-13 protein

What it means: Target is the identity of the recombinant protein you are purchasing. The target on this page is IL-13.

How to interpret here: Use IL-13 as your “construct match” checkpoint—confirm it is the exact antigen/standard you need for your antibody validation, binding assay, or functional study. The expressed construct/region is AAK53823.1, Met 1-Asn 132—use it to verify your epitope/domain is included. The expression system is CHO Stable Cells, which can affect folding and post‑translational modifications. Purity is listed as > 92 % as determined by SDS-PAGE, which helps you judge background tolerance for your assay. Choose this when target + origin + construct details align with your experiment; consider another construct if you need full‑length protein, a different domain, a tag‑free format, or native PTMs.

Why it matters for buying:

• Specificity and binding: Closely related family members, isoforms, or fragments can change antibody/ligand binding.
• Assay validity: The same target produced in different systems or constructs can behave differently in ELISA coating, BLI/SPR, pull‑downs, or activity assays.
• Reproducibility: Documented construct details reduce surprises between batches and between publications.

Helpful selection notes for this listing:

• Accession cross‑check: IL-13 is linked to accession AAK53823.1 for sequence/domain verification when needed.
• Protein length: The recombinant human IL-13 consists of 112 amino acids and migrates as an approximately 12.5 kDa band in SDS-PAGE under reducing conditions as predicted. (useful for confirming full‑length vs fragment).
• Synonyms: ALRH, IL-13, P600, Interleukin-13, IL13.

Practical guidance:

• Confirm your binding site: Map your antibody epitope or functional domain to the expressed region before ordering for a critical assay.
• Plan a pilot: Test a small amount first to confirm binding/activity under your exact buffer and immobilization conditions.
• Use controls: Include buffer‑only and an unrelated protein control to detect non‑specific binding.
• Buffer awareness: Formulation is Lyophilized from sterile PBS, pH 7.4—confirm compatibility with your downstream chemistry.
• Stability planning: Storage is Lyophilized Human IL-13 proteinshould be stored desiccated below -20°C. Upon reconstitution, the protein should be stored at 4°C between 2-7 days and for future use below -20°C. For long term storage it is recommended to add a carrier protein (0.41% HSA or BSA). Please prevent freeze-thaw cycles.—aliquot to avoid repeated freeze–thaw.

What to watch out for:

• PTM‑dependent epitopes: Some antibodies/ligands require glycosylation or native folding—confirm the expression system supports what you need.
• Tag interference: Tags can introduce extra epitopes or steric effects; use tag‑controls when interpreting binding data.
• Construct mismatch: A protein fragment can be excellent for epitope mapping but may not reproduce full‑length functional behavior.

What it means: Expression Region describes the exact construct that was expressed and purified (full‑length vs fragment, domains, and sometimes built‑in tags). The value on this page is AAK53823.1, Met 1-Asn 132.

How to interpret here: Treat AAK53823.1, Met 1-Asn 132 as the “what you actually get” definition. For IL-13, confirm this region includes your epitope/domain of interest. Use accession AAK53823.1 to map domains/isoforms in sequence databases. The region suggests an amino‑acid span of Met1–Asn132, which can help you verify coverage and expected size. Protein length (The recombinant human IL-13 consists of 112 amino acids and migrates as an approximately 12.5 kDa band in SDS-PAGE under reducing conditions as predicted.) provides an additional check for full‑length vs fragment. Pair this with the expression system (CHO Stable Cells) when assessing PTM/conformation requirements. Choose this when the construct definition matches your assay design; avoid mismatches when your antibody/ligand targets a domain that may be missing.

Why it matters for buying:

• Epitope inclusion: Many binding failures come from ordering a fragment that does not contain the epitope.
• Functional relevance: Full‑length and fragments can behave differently in activity assays or conformational binding.
• Immobilization and detection: Built‑in tags or fusion regions can change how the protein coats plates or binds capture surfaces.

Practical guidance:

• Map the domain: If you know the domain/epitope, verify overlap with the region before ordering for a key experiment.
• Plan QC on arrival: Verify size and major species by SDS‑PAGE/Western for critical work.
• Control for constructs: If comparing variants, use the same region/expression system to reduce confounding.

What to watch out for:

• Signal peptide/TM removal: Many constructs omit signal peptides or transmembrane regions; this can change conformation.
• PTM‑dependent sites: Fragments expressed in bacteria may not reproduce native glycosylation/disulfide patterns.
• Tag assumptions: Do not assume tags are cleavable or positioned at a specific terminus unless stated.

What it means: Expression System is the production host used to express the recombinant protein. The expression system listed here is CHO Stable Cells.

How to interpret here: Use CHO Stable Cells to predict whether the protein will be “native‑like” for your application (folding, disulfides, and post‑translational modifications). For IL-13, choose an expression system compatible with your binding or functional requirements. Pair host choice with formulation (Lyophilized from sterile PBS, pH 7.4) when planning downstream chemistry and stability. Follow the listed storage conditions (Lyophilized Human IL-13 proteinshould be stored desiccated below -20°C. Upon reconstitution, the protein should be stored at 4°C between 2-7 days and for future use below -20°C. For long term storage it is recommended to add a carrier protein (0.41% HSA or BSA). Please prevent freeze-thaw cycles.) to preserve structure after reconstitution. Choose this when host limitations do not conflict with your assay; consider mammalian/insect expression when native PTMs or complex folding are critical.

Why it matters for buying:

• PTMs and conformation: Host affects glycosylation, disulfide bonding, folding, and oligomerization—key for many epitopes and receptors.
• Assay background: Host-related impurities can influence low-signal assays; bacterial systems may also introduce endotoxin relevant to cell-based work.
• Comparability: Use the same expression system when comparing binding across constructs to reduce confounding.

Practical guidance:

• Validate early: Run a small pilot with your antibody/ligand under your exact buffer and immobilization conditions.
• Consider PTM sensitivity: If your reagents recognize glycosylated or conformational epitopes, verify the host can reproduce them.
• Use controls: Include an unrelated protein produced in the same host to help interpret host-driven background.

What to watch out for:

• “Works in cells” assumptions: A recombinant protein may be suitable for binding assays but not necessarily for cell stimulation without additional validation.
• Aggregation risk: Some proteins aggregate depending on host and buffer—reconstitute gently and avoid repeated freeze–thaw.
• Activity expectations: Do not assume enzymatic or receptor activity unless explicitly validated in the datasheet.

What it means: Purity indicates how clean the preparation is (often estimated by SDS‑PAGE). The purity statement shown here is > 92 % as determined by SDS-PAGE.

How to interpret here: Use > 92 % as determined by SDS-PAGE to judge whether the protein is suitable for your assay’s background tolerance and sensitivity. For IL-13, higher purity is especially helpful when using the protein as a quantitative standard or in low-signal binding experiments. Also consider formulation (Lyophilized from sterile PBS, pH 7.4), which can influence non‑specific binding and stability. Follow storage guidance (Lyophilized Human IL-13 proteinshould be stored desiccated below -20°C. Upon reconstitution, the protein should be stored at 4°C between 2-7 days and for future use below -20°C. For long term storage it is recommended to add a carrier protein (0.41% HSA or BSA). Please prevent freeze-thaw cycles.) to preserve integrity after reconstitution. Shipping (The product is shipped at ambient temperature.) can affect thermal exposure; inspect and aliquot promptly after receipt. Choose this when the stated purity meets your use-case; consider higher purity/extra QC for quantitative standards, kinetics, or cell-based assays.

Why it matters for buying:

• Lower background: Impurities can increase non‑specific binding in ELISA coating and surface binding assays.
• Reproducibility: Cleaner preparations generally reduce variability across runs and lots.
• Downstream compatibility: Contaminants can confound functional assays or create false binding signals.

Practical guidance:

• Match purity to application: Screening may tolerate lower purity; quantitative standards and kinetics benefit from cleaner prep.
• QC on arrival: For critical work, confirm band size and major species by SDS‑PAGE/Western.
• Use controls: Include buffer and unrelated protein controls to interpret background binding.

What to watch out for:

• Purity method differences: SDS‑PAGE estimates do not guarantee a single molecular species (aggregates/fragments may exist).
• Aggregation: Purity does not report aggregation—reconstitute gently and inspect solubility if binding looks inconsistent.
• Cell-based sensitivity: For cell assays, confirm endotoxin/host contaminants if unexpected responses occur.