All 22 custom antibody services — discovery, engineering, developability →
Custom Antibody Services · RabWiz™ Platform

Rabbit monoclonals for the targets that defeat everyone else.

GPCRs, ion channels, phospho-sites, anti-idiotypes, single small molecules — the antibodies that hybridoma and B-cell screening quietly miss. RabWiz™ pairs the rabbit immune response with phage-display selection to find the rare, functional clone others can't reach.

400+
rabbit immune libraries built
4–5 mo
immunization → validated mAb
pM
typical lead affinity (vs nM for mouse)
Since 2012
only lab to solve rabbit Fab display in E. coli
The problem most platforms won't tell you

You can only screen antibodies your method actually captured.

The best antibody against your target is often a rare clone hiding on a minor epitope. If the discovery method never captured it, no amount of screening brings it back — and you'll never know it was there. Here's how the common approaches compare.

 HybridomaB-cell cloningRabWiz™ (Abwiz)
Repertoire captured10⁴–10⁵ cells10⁴–10⁵ cellsUp to 2×10¹⁰ — full immune diversity
Rare / minor-epitope clonesOften lostOften lostCaptured & selectable
Remove cross-reactive clonesNoNoYes — competitive selection
Rabbit Ck1 clones (70–90% of serum)PartialPartialFully accessible (engineered vector)
Re-screen after new target insightOne-shotOne-shotLibraries archived — re-select anytime
Native H/L chain pairingYesYesYes — retained through cloning
Why RabWiz™ works

Three advantages, one integrated platform.

Why rabbits

Rabbit CDRs are more diverse than human or mouse — and their light chains nearly as diverse as heavy chains. The result is exquisite specificity and typically picomolar affinity, plus responses to targets that are invisible to the mouse immune system.

Why phage display

Access libraries up to 2×10¹⁰ and apply selection pressure hybridoma can't: competitive ELISA to pull single-molecule specificity, subtractive panning on cells, and epitope-masking to force neutralizing clones out of hiding.

Why only Abwiz

Rabbit Ck1 clones — 70–90% of the serum response — carry extra cysteines and historically wouldn't express in E. coli. We engineered a phagemid vector that displays them. Other platforms fall back to scFv or chimeric constructs and miss that majority of the repertoire.

Timeline

Immunization to validated IgG in ~4–6 months.

1

Immunization

~2 months
  • Antigen preparation
  • Rabbit immunization
  • Serum analysis
2

Library construction

3+ weeks
  • WizAmp™ gene cloning
  • Optimized rabbit-Fab phagemid
  • QC report
3

Panning / screening

3+ weeks
  • Phage panning
  • Fab ELISA / flow
  • Full VH/VL sequences
4

IgG production

3 weeks
  • HEK293 expression
  • ~1 mg purified IgG
  • Validation + affinity
Need it humanized or affinity-matured? Continue straight into STEM™ in the same pipeline — no restart.
Case studies

Published proof on hard targets.

Over 400 libraries against hundreds of targets. A few examples where RabWiz™ selection reached antibodies conventional screening can't.

GPCR · sulfation-site specificPublished 2025

Antibody that reads a single sulfation site on CCR5

Sulfated-peptide immunization → WizAmp™ immune Fab library → counter-selection with CCR5 / TPST cell screening. The clone (BA8) tells apart sulfation state and site, and binds full-length CCR5 on the cell surface.

0.81 nM
KD to fully sulfated CCR5 peptide — no measurable binding to non-sulfated
~56×
affinity gain from Tyr15 sulfation — site-level resolution
3.64–3.71 nM
BC₅₀ on full-length CCR5 (flow + Western)
Ujiie et al., J Biol Chem 2025;301:108176 · doi:10.1016/j.jbc.2025.108176 · PDB 9J8A
CCR5 flow cytometry binding data with BC50 curves
Alpaca VHH · picomolarPublished 2022

A 1-picomolar nanobody to a flexible loop others can't reach

The same WizAmp™ + phagemid vector that displays cysteine-rich rabbit Ck1 Fabs is ideal for cysteine-rich VHH libraries. Against complement factor H, it delivered functional clones with unusually long, disulfide-stabilized CDR3s.

1.71 pM
KD (VHH4) to the CFH CCP20 loop
8–27 aa
CDR-H3 length range recovered from one library
Functional
VHH4 inhibited CFH and induced hemolysis
J Biol Chem 2022;298:101962
CFH VHH SPR, ITC, and functional hemolysis data
Real-time engineering · humanizationPublished 2023

A neutralizing lineage engineered to keep pace with variants

From Wuhan-Hu-1 RBD immunization to a parental rabbit clone (C-A11), humanized (hN2Y) and then STEM™-matured to broadly neutralize Omicron sublineages — validated by CoVIC at La Jolla Institute.

<1 pM
Beta-variant KD after maturation
BA.1→JN.1
breadth extended across evolving Omicron variants
Antib Ther 2023;6(2):108–118 · Cell Rep 2023;42(1):112014
COVID-19 humanization and neutralization data tables
Companion diagnostics

Anti-idiotype antibodies

Both Type 1 (drug-antibody specific) and Type 2 (drug/antigen-complex only) anti-idiotypes for PK assays and immunogenicity controls — selected by competitive phage panning.

Ion channels & GPCRs

Native membrane targets

Functional mAbs against CB1, CB2, PAR1 and the ion channel Kv1.3 — all recognizing the native, cell-displayed receptor, using peptide, ECL-Fc, cell and RNA formats.

Haptens

Single-molecule discrimination

A rabbit mAb specific to an oxidized nucleoside with no reactivity to near-identical small molecules — reachable only through competitive selection, not screening.

PTMs & cancer

Phospho-sites and cell immunization

Phospho-specific mAbs that hold up in WB/IHC/flow via paired peptide + native-cell panning; and cancer-cell-specific clones from subtractive panning on primary cells — re-selectable from archived libraries.

One platform, many formats

Not just rabbit — the same library technology extends across formats.

WizAmp™ uniform single-primer amplification and our cysteine-tolerant phagemid vector aren't rabbit-specific. The approach that captures a full rabbit repertoire applies to VHH, mouse and human antibody development — with matching humanization and STEM™ affinity maturation in the same pipeline.

Rabbit mAbs · core

Rabbit discovery & engineering

Our core platform: high-affinity, highly specific rabbit mAbs against difficult targets, then humanization and maturation as needed.

400+
immune libraries · pM leads on GPCRs & ion channels
VHH · nanobodies

Camelid VHH libraries

The same cysteine-tolerant vector displays cysteine-rich VHH libraries that conventional phagemids can't — ideal for nanobody discovery.

1.71 pM
published anti-CFH nanobody (J Biol Chem 2022)
Mouse mAbs

Mouse & chimeric engineering

Immune-library discovery and STEM™ engineering applied to mouse-derived and chimeric antibodies — potency and developability, not just binding.

3.5×
anti-TNF-α potency gain, aggregation nearly eliminated (STEM™)
Human antibodies

Human & humanized leads

Humanization to human frameworks and STEM™ affinity maturation of human and humanized therapeutic leads — ready to hand off for development.

5.1 nM → 473 pM
client human therapeutic Fab (10.8×, client-patented)
FAQ

Common questions.

Should we use rabbit or mouse antibodies?
Rabbits recognize a broader epitope repertoire — including small molecules, phospho-sites and human self-antigens — and typically reach picomolar affinity where mouse mAbs sit at nanomolar. For diagnostics, IHC and therapeutic leads, rabbit is usually the stronger starting point.
How is this different from hybridoma or B-cell cloning?
Those methods sample only 10⁴–10⁵ cells and can't apply downstream selection, so rare clones on minor epitopes are frequently lost with no way to recover them. RabWiz™ captures up to 2×10¹⁰ and lets us actively select for the clone you need — then archives the library so it can be re-screened later.
Do rabbit Fabs really work in phage display?
They do with our vector. Rabbit Ck1 clones (70–90% of the serum response) carry extra cysteines and historically wouldn't express in E. coli. We engineered a phagemid that displays them, so we access the full repertoire instead of the scFv/chimeric subset other platforms are limited to.
Can you humanize the rabbit mAb afterward?
Yes. Rabbit germline usage is limited even though CDR diversity is high, so a consistent humanization strategy works across leads. Many customers run discovery and humanization (and STEM™ affinity maturation) in one continuous pipeline.
Are the heavy and light chains natively paired?
Native pairing is retained through our cloning process, rather than randomly recombined.

Have a target that's beaten other platforms?

That's exactly what RabWiz™ was built for. Tell us the antigen and the assay it needs to work in — we'll tell you whether we can reach it.

Get in touch