Anti-MMP-17 Rabbit Polyclonal Antibody

Frequently Asked Questions

What molecular weight should I expect for MMP-17 on a Western blot?

MMP-17 is synthesized as a 603-amino acid precursor with a predicted molecular weight around 57 kDa. However, because MMP-17 is a heavily glycosylated GPI-anchored protein, it typically migrates at approximately 65-70 kDa on SDS-PAGE under reducing conditions. The apparent shift reflects post-translational modifications including N-linked glycosylation. If you see multiple bands, consider that partial glycosylation states or proteolytic processing may occur depending on cell type and expression levels. Always include a positive control lysate from cells known to express MMP-17, such as breast carcinoma or leukocyte lines.

Does this MMP-17 antibody distinguish between active and zymogen forms?

This polyclonal antibody is raised against a broad epitope region spanning residues within the catalytic and hinge domains, so it recognizes both the inactive pro-MMP-17 zymogen and the mature active enzyme. It does not selectively detect the activated form. MMP-17 activation involves removal of the prodomain by furin-like proprotein convertases, but the epitope recognized by this antibody remains intact post-activation. If you need to discriminate activation states, consider combining Western blot data with a functional activity assay or use a prodomain-specific antibody as a complementary reagent.

What is the recommended starting dilution for Western blot with this MMP-17 antibody?

We recommend a starting dilution of 1:1000 for Western blot applications. This dilution has been validated with human samples and typically yields clean, specific bands when loading 20-40 µg of total protein per lane. Because MMP-17 is a membrane-tethered protein, prepare lysates in buffers containing detergent to solubilize membrane fractions effectively; RIPA buffer works well. Optimize the dilution and exposure time based on your specific expression levels. Low-abundance samples may benefit from dilutions as concentrated as 1:500, while overexpressed cell lines may tolerate 1:2000.

Is this antibody validated for rat or mouse MMP-17, or only human?

This antibody has been validated with human MMP-17. Cross-reactivity with rat MMP-17 is predicted based on sequence homology within the immunogen region, but you should confirm specificity empirically with appropriate positive and negative controls. Pan (chimpanzee) and dog cross-reactivity are also predicted but not experimentally validated. Mouse MMP-17 shares lower sequence identity in critical epitope regions, so cross-reactivity is uncertain. If working with rodent samples, we recommend testing the antibody alongside a known human positive control and verifying band size corresponds to the expected species-specific molecular weight before committing to full experiments.

Can I use this antibody for immunofluorescence or IHC on MMP-17?

Yes, Triple Point Biologics antibodies are validated for Western blot; immunohistochemistry and immunofluorescence validation is in progress. Because MMP-17 is GPI-anchored and membrane-localized, you should see staining at the cell surface and in membrane ruffles or protrusions where active remodeling occurs. For IHC, antigen retrieval is typically required; citrate buffer pH 6.0 is a reasonable starting point. For IF, use a mild permeabilization step if you want to enhance intracellular pre-cursor detection, but avoid over-permeabilization that strips membrane-bound mature MMP-17.

What cell types or tissues should I use as positive controls for MMP-17 expression?

MMP-17 is expressed in activated leukocytes, brain tissue, and various carcinoma cell lines. Breast cancer cell lines such as MCF-7 or MDA-MB-231, and certain glioblastoma lines, are commonly used as positive controls for Western blot and IHC. Normal human brain lysate also expresses detectable MMP-17. For negative controls, consider tissues or cell lines with minimal or absent MMP-17 mRNA by RNA-seq databases; fibroblasts and some epithelial lines show low basal expression. Including both a validated positive control and a predicted negative control will help you interpret staining specificity and troubleshoot non-specific background.

Does MMP-17 cleave fibrillar collagens, and what substrates should I focus on?

No, MMP-17 does not hydrolyze fibrillar collagens type I through V, gelatin, fibronectin, laminin, or decorin. Its substrate selectivity is narrow compared to other MMPs. MMP-17 cleaves fibrin and, notably, pro-TNF-α at the Ala74-Gln75 site, releasing soluble TNF-α. It has been implicated in processing membrane-bound precursors of growth factors and inflammatory mediators. If you are investigating MMP-17 function, focus on TNF-α shedding assays, fibrin degradation, or activation of pro-forms of cytokines. Avoid assuming broad matrix-degrading activity; MMP-17 is more specialized in pericellular proteolysis than classical secreted MMPs.

How should I store this MMP-17 antibody and what is its expected shelf life?

Store the antibody at -20°C in small aliquots to avoid repeated freeze-thaw cycles, which can reduce titer and increase aggregation. The 100 µg pack size is sufficient for approximately 100 Western blots at 1:1000 dilution. Once thawed, an aliquot can be kept at 4°C for up to one month if supplemented with 0.02 percent sodium azide as a preservative, but long-term storage should remain frozen. Typical shelf life is two years from the date of manufacture when stored properly. Avoid exposure to light and do not store in frost-free freezers where temperature cycling occurs.