Complement Assays

Simultaneous study of all complement responses - in one assay.

Customer Promise



Evaluate complement activation, inhibition, and other immune responses simultaneously.



Immuneed's platform, ID.Flow, is based on fresh, circulating human blood and is unique in having an intact, and active complement system.



Tailored study design and flexible scientific reports.

Complement Assay

How does your drug interact with the human complement system?

Complement activation or inhibition could influence your drug’s function, whether you anticipate it or not. The human complement system comprises upwards of 40 proteins. Although small, these proteins can trigger a massive immune response, starting a cascading reaction that stimulates phagocyte activation, inflammation, and membrane attack complex. In a clinical trial, they can be the source of significant infusion reactions, such as hypersensitivity reactions caused by the complement system.  These include reactions based on complement-dependent cytotoxicity (CDC), which can be prevented through antibody modification. But they also include reactions based on antibody-dependent cell-mediated cytotoxicity (ADCC), which is frequently overlooked. The latter can occur via the alternative pathway, which remains active even when the classical pathway has been blocked. You get the complete picture by including complement evaluation in your preclinical testing.

Why complement must be assessed in fresh human blood

Tests based on plasma from rabbits or other animals are limited in what they can reveal. Likewise, in vitro testing in animals – including apes – is an imperfect analogy for a human environment. Immunee’ds platform ID.Flow, is based on fresh, circulating human blood and is unique in having an intact, and active complement system.

The Figure above shows a study of complement activation in ID.Flow.  The figure shows the activation of complement subunits C3a and C5a as assessed by ELISA in fresh human blood from five healthy donors. The donor responses are compared to PBS (vehicle) and different monoclonal antibody controls in ID.Flow as compared to blood collected before addition to ID.Flow (zero sample).

Analysis by ID.Flow

Your drug is infused into fresh human blood in circulation.
Read-outs are taken to perfectly mimic the clinical situation of infusion reactions.
The multiplexing platform from MesoScale Discovery (MSD) is used for analyzing the samples.
The MSD platform supplies over 100 validated immunoassays that deliver reproducible and reliable results.

Read Outs

Complement activation: C3a, C5a and SC5b-9
Simultaneous evaluation of CDC and ADCC
Complete blood count: hematology parameters.

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Have a project or a question? We'd be happy to hear from you.

5 step guide

Five-step guide to improving preclinical testing from a complement perspective. When evaluating drug function and safety, don’t overlook – or underestimate – the complement system.