Anti-Chitinase-1 Rabbit Polyclonal Antibody

Frequently Asked Questions

What molecular weight band should I expect for Chitinase-1 on Western blot?

Human CHIT1 migrates at approximately 50 kDa on reducing SDS-PAGE, corresponding to the mature secreted form after signal peptide cleavage from the 466-residue precursor. You may observe additional bands at higher molecular weights due to glycosylation, as CHIT1 contains multiple N-glycosylation sites. In some lysates, particularly from activated macrophages, a 39 kDa catalytic domain fragment can appear following proteolytic processing. The intensity and pattern depend heavily on cell activation state and the presence of endogenous proteases during sample preparation.

Does this antibody distinguish between enzymatically active and inactive CHIT1 isoforms?

This polyclonal antibody is raised against a broad epitope range and will likely recognize multiple CHIT1 isoforms, including the enzymatically inactive isoform 3, which lacks the catalytic domain due to alternative splicing. The antibody does not selectively detect only active enzyme. If your experimental goal requires distinguishing active from inactive forms, consider coupling Western blot detection with a functional chitin hydrolysis assay on the same samples, or use isoform-specific primers for transcript analysis to confirm which variants are expressed.

What starting dilution should I use for Western blot with this Chitinase-1 antibody?

Start at 1:1000 dilution in your blocking buffer for Western blot, as recommended. CHIT1 expression varies widely depending on macrophage activation status; resting macrophages express very low levels while activated cells or Gaucher disease patient samples show markedly elevated protein. If you see no signal at 1:1000 with control lysates known to express CHIT1, try 1:500. Conversely, if background is high, dilute to 1:2000. Optimal dilution depends on your detection system sensitivity and sample CHIT1 abundance.

What positive control lysate should I use to validate Chitinase-1 detection?

PMA-activated THP-1 cells or primary human macrophages stimulated with LPS or interferon-gamma serve as strong positive controls, as CHIT1 is robustly upregulated in activated macrophages. Alternatively, conditioned medium from these cells concentrates the secreted enzyme. Patient plasma or lysates from Gaucher disease models also show elevated CHIT1. Negative controls should include unstimulated monocytes or non-myeloid cell lines like HeLa or HEK293, which express minimal to undetectable CHIT1 under basal conditions. Always include molecular weight markers spanning 35-70 kDa.

Is this Chitinase-1 antibody cross-reactive with mouse or rat samples?

This antibody is validated only for human CHIT1. Cross-reactivity with mouse or rat chitinases has not been experimentally confirmed. Human and mouse CHIT1 share approximately 77% sequence identity, suggesting potential cross-reactivity, but species-specific glycosylation patterns and epitope accessibility differences may affect binding. If you are working with rodent samples, we recommend treating this antibody as having predicted but unvalidated cross-reactivity. Test it empirically alongside a species-validated control, or consider a pan-mammalian chitinase antibody if available.

Can I use this antibody for immunohistochemistry on paraffin-embedded tissue?

Triple Point Biologics antibodies are validated for Western blot; IHC application data is in progress as part of our standard workflow. For CHIT1 detection in FFPE tissues, antigen retrieval is typically required; start with citrate buffer pH 6.0 at sub-boiling temperature for 20 minutes. CHIT1 localizes primarily to activated macrophages in granulomas, foam cells in atherosclerotic lesions, and Gaucher cells in storage disease tissues. Use spleen or liver sections from Gaucher patients as positive controls. Optimal antibody dilution for IHC often differs from Western blot; begin titration at 1:200 to 1:500.

How should I store this Chitinase-1 antibody and what is the expected stability?

Store the antibody at -20°C in single-use aliquots to avoid repeated freeze-thaw cycles, which can reduce binding activity. If you use the antibody frequently, a working aliquot can be kept at 4°C for up to one month with 0.02% sodium azide as preservative. Do not store diluted antibody; prepare fresh working solutions for each experiment. Polyclonal rabbit antibodies typically remain stable for 12-24 months under these conditions. Check for precipitate before use; if present, centrifuge briefly and use the supernatant. Avoid prolonged exposure to room temperature.

Why am I seeing multiple bands on Western blot with the Chitinase-1 antibody?

Multiple bands are common with CHIT1 detection and reflect biological heterogeneity rather than antibody non-specificity. The 50 kDa band represents full-length mature protein, while a 39 kDa band corresponds to the catalytic domain after proteolytic cleavage. Variable glycosylation produces diffuse or laddered bands between 50-60 kDa. If you observe bands below 35 kDa or above 70 kDa, consider degradation during sample prep; use fresh protease inhibitors and minimize freeze-thaw. The inactive isoform 3 may also contribute distinct bands depending on cell type and splicing patterns.