Catalog Overview

Triple Point Biologics' antibody catalog comprises 981 epitope-specific rabbit polyclonal antibodies directed against 305 proteinase and endogenous inhibitor targets. The catalog is organized around the four classical mechanistic families — aspartic proteinases, cysteine proteinases, serine proteinases, and metalloproteinases — and extends to their cognate endogenous inhibitors, including TIMPs, cystatins, serpins, and calpastatin.

Catalog development began in 1994. Over 32 years, the antibody lineup has been built incrementally as individual proteinase families were characterized at the domain level, with each new antibody tied directly to a defined epitope region rather than to a whole-protein immunogen. The result is a reference collection organized by mechanism, target, and domain rather than by application or species.

Each antibody in the catalog has a directly matched recombinant protein produced in the same facility, expressed in HEK293 cells, and available as a positive control and validation standard. This matched-pair architecture is described in detail in the recombinant protein positive controls guide.

Mechanism Family Coverage

Metalloproteinases

The metalloproteinase collection is the largest in the catalog, covering the MMP family (MMP-1 through MMP-28), the ADAM family (ADAM10, ADAM17), the ADAMTS family, and the membrane-type MMPs (MT1–MT6-MMP). Endogenous inhibitors in this section include TIMP-1, TIMP-2, TIMP-3, and TIMP-4, each covered by domain-specific antibodies targeting distinct structural regions.

Cysteine Proteinases

The cysteine proteinase collection spans the lysosomal cathepsins (cathepsins B, F, H, K, L, S, and V), the calcium-dependent calpains (μ-calpain, m-calpain), and granzyme B. Inhibitors covered include the cystatins (cystatin A, B, C, D, E/F, S, SN) and calpastatin. Cathepsin K and cathepsin L antibodies in particular reflect depth of coverage, with multiple antibodies per target mapping to propeptide, catalytic, and C-terminal domains independently.

Aspartic Proteinases

The aspartic proteinase collection includes BACE1, BACE2, cathepsin D, cathepsin E, and the presenilins. These targets are of particular relevance to neurodegeneration and lysosomal biology research programs. Antibodies are raised against epitopes across the pro-domain and the bilobed catalytic domain to enable differentiation of precursor and mature processed forms.

Serine Proteinases

The serine proteinase collection covers the tissue kallikreins (KLK1–KLK15), the granzymes, the complement MASPs (MASP-1, MASP-2), TMPRSS2, furin, the PCSK family, plasminogen and its derived fragments, and neutrophil elastase. Serine proteinase inhibitors represented include the serpins across SERPINA, SERPINB, SERPINC, SERPINE, SERPING, and SERPINH subfamilies.

Domain-Specific Epitope Approach

A defining structural feature of this catalog is the use of domain-specific immunogens. Rather than raising antibodies against full-length protein or uncharacterized lysate fractions, each antibody is generated against a defined domain or peptide region — for example, a rabbit polyclonal raised against residues 46–460 of the catalytic domain of MMP-14, or one raised against the prodomain of cathepsin K (residues 16–99).

The practical consequence is that multiple antibodies exist for many targets, each capable of detecting a distinct structural form: zymogen versus mature enzyme, full-length versus processed fragment, inhibitor-bound versus free enzyme. Researchers studying proteinase activation cascades or ectodomain shedding events benefit from the ability to distinguish these forms in the same experiment using antibodies from the same catalog, raised under comparable immunization and purification conditions.

Domain mapping for each antibody is annotated on the individual product pages, cross-referenced against UniProt domain boundaries where applicable. Predicted species cross-reactivity is listed per antibody based on epitope sequence conservation, and is noted as predicted rather than validated unless wet-lab data is available.

Superpooled Kits

The Superpooled Kit format is a TPB-specific reagent configuration in which multiple epitope-specific rabbit polyclonal antibodies directed against the same target are formulated together into a single vial. Rather than selecting a single antibody raised against one domain, researchers receive a pooled reagent with broader epitope coverage across the target protein in one working solution.

This format is particularly useful in applications where antigen accessibility is uncertain — for example, in formalin-fixed paraffin-embedded tissue sections where epitope masking may reduce the effective signal from any single antibody — or in Western blot experiments with partially degraded or post-translationally modified samples. The Superpooled Kits collection lists all available pooled configurations by target.

Each Superpooled Kit is built from antibodies that are individually characterized before pooling. The component antibodies, their epitope regions, and their individual validation data are documented on the kit product page. Pooled kits are not a substitute for domain-resolved detection; they are a separate format for applications where composite coverage is preferred over isoform discrimination.

Matched Recombinant Proteins

Every antibody in the catalog has a corresponding recombinant protein produced at the same facility, expressed in HEK293 mammalian cells. These recombinant proteins serve as positive controls for Western blot and immunohistochemistry workflows, and as the primary validation standards for antibody lot qualification.

Because the recombinant proteins and antibodies are produced in parallel under defined conditions, they provide a more tractable validation system than cell lysate standards, which vary in proteinase expression level, post-translational processing state, and inhibitor context. The recombinant proteins are available separately through the recombinant proteins catalog, and their use in validation workflows is described in the positive controls guide.

Matched pairs are also directly applicable to activity assay development: recombinant protein serves as the active enzyme or inhibitor standard, while the cognate antibody enables capture, detection, or inhibition confirmation steps. The protease activity assay guide covers paired-reagent experimental design in detail.

Validation Approach

Antibodies in this catalog are validated for Western blot applications. Validation data are generated using the matched HEK293-expressed recombinant protein as the positive control antigen, with molecular weight confirmation against predicted values from UniProt sequence annotations.

For IHC applications, antibodies are tested on formalin-fixed paraffin-embedded human tissue sections representing tissues with documented expression of the target. Staining patterns are cross-referenced against published expression databases. Species cross-reactivity is validated for human in all cases; reactivity against mouse, rat, cynomolgus monkey, dog, and pig is determined by epitope sequence alignment and confirmed by wet-lab data where available. Cross-reactivity status — validated versus predicted — is documented explicitly per antibody rather than claimed categorically.

Full validation documentation, including lot-specific data, is available through the quality and validation page.

Applications and Assay Guidance

The antibodies in this catalog are applicable across the standard immunodetection workflow:

• Western blot: Detection of proteinase and inhibitor expression in cell lysates, conditioned media, and tissue extracts. Domain-specific antibodies are particularly useful for distinguishing zymogen (pro-form) from activated enzyme by molecular weight shift.
• Immunohistochemistry: Localization of proteinase and inhibitor expression in tissue sections, including tumor microenvironment, fibrotic tissue, and neurological tissue panels. Superpooled Kits are available for targets where single-epitope antibodies have shown variable performance in fixed tissue.
• Immunofluorescence: Subcellular localization of lysosomal cysteine proteinases (cathepsins B, D, K, L, S), validated in standard cell culture models.
• Activity assay integration: Antibody-based capture combined with matched recombinant enzyme or inhibitor standards for ELISA-format activity and inhibition assays. See the protease activity assay guide for experimental design considerations.

Species coverage is target-dependent and reflects epitope conservation. Antibodies raised against epitopes within regions of high evolutionary conservation across mammals tend to show predicted cross-reactivity to mouse and rat; those raised against divergent pro-domain regions may be restricted to human. Species reactivity for each antibody is annotated on the product page.

For custom antibody generation against proteinase targets not currently in the catalog, or for antibodies raised against specific splice variants, mutant forms, or non-standard species, the custom services page describes available programs.