Complement Activation & Inhibition

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

A complete picture of your drug’s interaction with the complement system

Complement activation or inhibition could have an influence on 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 drug 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. By including complement evaluation in your preclinical testing, you get the full picture.

Why it’s important to test on 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. If using human blood is important, so is choosing a test environment that’s as similar as possible to the human body. Whole blood is a more realistic and relevant environment than plasma. However, whole blood assays require high levels of anticoagulants which result in partial inactivation of complement and coagulation. Immuneed’s platform, ID.Flow, is based on fresh, circulating human blood and is unique in having an intact, and active complement system.

A study of complement activation levels: Above you can view the results from our study of complement activation in circulating blood in the ID.Flow system. Freshly acquired whole blood was incubated with complement activators anti-CD52 antibody (activator of the classical pathway), LPS (activator of the alternative pathway) or negative comparators (vehicle/negative control). Complement activation (measured by plasma C5a) was measured at the 15-minute time point and plotted as fold-change over zero-time point (measurement directly after blood acquisition).

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.