Target Proteins

How to get your target into an Adaptyv experiment, and what we need from it.

Every binding experiment starts with a target protein. You can pick one from our catalog, ask us to source or express it, or ship us your own. This page covers all three routes, the spec your target has to meet, and which targets need a feasibility check first.

Choosing a sourcing route

Route	How it works	Best when
Catalog target	Pick from targets.adaptyvbio.com, the targets available through our regular suppliers.	Your target is listed. This is the fastest way to start.
We source it	We buy the target from a commercial vendor, or express it in house if it is not purchasable.	Your target is not in the catalog.
You supply it	You ship us purified protein that meets the spec below.	You already have material, or the target is proprietary.

The target reagent cost is passed through to you separately. It is not part of the per-design assay price. See adaptyvbio.com/services for current pricing.

Catalog targets

The catalog lists the targets we can obtain through our regular commercial suppliers. A listing means the protein is readily available to order, not that we have run it before, so picking from the catalog mainly saves sourcing time rather than guaranteeing prior experience with that antigen.

Browse the full list at targets.adaptyvbio.com before you request a custom target. If we have run your target previously we will say so when we quote, and we will reuse suitable material we already hold.

Targets we source for you

If your target is not in the catalog, tell us the protein, the species and the region or domain you care about, and we will source it.

In most cases we buy it from an external commercial vendor, most commonly from Acro Biosystems, Sino Biological, and Kactus Biosciences.

If the target is not commercially available, we may be able to express it in house, provided it is compatible with our cell-free expression system. When the target expresses well, turnaround stays within roughly four weeks.

In-house production runs as a ladder:

1. Expression screen

   A small-scale run to confirm the target expresses at all in our system. This is the go or no-go step.

2. Mid-scale or large-scale production

   Scale-up, purification and quality control, sized to how much material your experiment needs.

Pricing for each step depends on scale, so ask us for a quote or see adaptyvbio.com/services.

Supplying your own target

You are welcome to send us your own material. To go straight into an assay, it should be:

• At 0.5 mg/mL or higher, ideally.
• In a standard buffer such as PBS or HEPES.
• Free of carrier protein. No BSA, no gelatin.
• Labelled with the concentration of any glycerol or sodium azide it contains, so we can account for it.

Around 150 ug is enough for a typical run.

Properly lyophilized protein does not need to ship on dry ice, which makes shipping simpler and cheaper.

Tag requirements

Tags on the target matter, because our binders are immobilized through their own tag.

Your target must not carry a Twin-Strep tag and must not be biotinylated. We immobilize binders via a Twin-Strep-tag onto a Strep-Tactin surface, so a Twin-Strep-tagged or biotinylated target competes for the same surface chemistry and will interfere with the assay.

Fc-tagged targets are fine to run. Be aware that the Fc dimerizes the target, so apparent affinity can be shifted by avidity. Flag an Fc tag when you set the experiment up so the results are interpreted correctly.

For background on how tags are used on the binder side, see Construct and tag design.

Harder targets

Soluble targets are the straightforward case. Membrane proteins are possible, but they carry additional challenges, so we usually start with a feasibility test to validate the target before committing to a full campaign. The same applies to targets that need a non-standard presentation format, such as detergents or nanodiscs. Ask us early and we will tell you what the feasibility step looks like for your specific target.

Many membrane proteins have soluble extra-cellular domains (ECD), that are much easier to work with than full length membrane proteins. Full-length is worth attempting when the epitope you care about is not in the ECD.

We do not run cell-based assays. Our binding assays measure a purified binder against a purified target.

Once your target is settled, see Binding for what the assay measures and Supported protein formats for what we can run on the binder side.

FAQ

Is the target included in the price?

No. The target reagent cost is passed through to you separately from the per-design assay price. Current pricing is at adaptyvbio.com/services.

Can you run a target that is not in your catalog?

Yes. We source most non-catalog targets from a commercial vendor, most commonly Acro Biosystems, Sino Biological, or Kactus Biosciences. If the target is not commercially available, we may be able to express it in house, provided it is compatible with our cell-free expression system. You can also supply the protein yourself.

Can you run a membrane protein?

Yes, with caveats. Membrane proteins carry additional challenges, so we usually run a feasibility test to validate the target first. If your target has an extracellular domain, running the ECD is substantially easier than the full-length protein and is normally the faster route to data. Send us the construct you have in mind and we will tell you which route makes sense.

How much target protein do you need?

Around 150 ug is enough for a typical run. If you are supplying the material yourself, send it at 0.5 mg/mL or higher in PBS or HEPES, without carrier protein.