Explore QuidelOrtho ELISAs and high-quality reagents for biological therapeutics research through complement-dependent cytotoxicity testing. Where immune activation meets therapeutic precision.
IVD | Complement | ELISA | Antibodies | Proteins | Serum | Donor Testing | POCT | Sample Collection | Instruments
The complement system is a network of 50+ individual proteins, protein complexes and fragments that drive a host’s innate immune response via three main pathways: alternative, classical and lectin. Complement-dependent cytotoxicity (CDC) is the natural mechanism by which therapeutics, most often humanized antibodies but also other non-antibody proteins and peptides, activate the complement system. This ultimately leads to the formation of the membrane attack complex (MAC), clearance of non-host materials and additional immune system response.
Biological therapeutics can induce CDC. This can be either a negative or positive outcome depending on the desired therapeutic goal:
Measuring CDC is important for assessing overall biocompatibility, requiring several parameters to accurately evaluate the potential contribution of the complement system.
| CDC assay material | Product description | Catalog # |
|---|---|---|
| Complement source and activators | Normal human serum (NHS) ▪ Source of human complement system proteins specially processed for minimal activation | A111 (1.0 mL) A112 (2.5 mL) A113 (5.0 mL) |
| Cobra venom factor (CVF) ▪ Purified snake protein that activates the complement system | A600 A601 (recombinant) | |
| Assay kits to detect complement activation | MicroVue CH50 EIA | A018 |
| MicroVue Ba EIA | A034 | |
| MicroVue Bb EIA | A027 | |
| MicroVue C3a Plus EIA | A032 | |
| MicroVue iC3b EIA | A006 | |
| MicroVue C4a EIA | A036 | |
| MicroVue C4d EIA | A008 | |
| MicroVue C5a EIA | A025 | |
| MicroVue sC5b-9 Plus EIA | A029 | |
| MicroVue Complement Multiplex ▪ Multi-analyte enzyme immunoassay (EIA) format multiplex to detect multiple complement proteins | Varies | |
| Complement EIA kits can be used to detect general and pathway-specific activation during CDC assays. Individual experimental needs may vary. ▪ General activation: C3a EIA, iC3b EIA, C5a EIA, sC5b-9 EIA ▪ Classical/lectin pathway: CH50 EIA, C4a EIA, C4d EIA ▪ Alternative pathway: Ba EIA, Bb EIA | ||
Materials needed for CDC assays that are not provided by QuidelOrtho include:
The following assay parameters are provided as guidelines only and are not intended to be inclusive of all possible variations of the experiment.
Terms and definitions:

The following reagent and assay suggestions may act as controls for proper materials performance.
| Materials | Description | Products needed |
|---|---|---|
| Biologic therapeutic + NHS | (–) Control: Evaluate if biologic therapeutic aggregates and activates complement while in soluble form. | NHS: Complement source CVF: Complement activator EIA kits: Complement protein detection (see product list section for specific kit recommendations) |
| Biologic control + NHS | (–) Control: Evaluate if non-therapeutic biological control activates complement. | |
| Therapeutic target + NHS | (–) Control: Evaluate if therapeutic targets activate complement (ex. surface carbohydrate initiates the lectin pathway). | |
| CVF + NHS | (+) Control: Provides data range for comparison if complement is activated in the CDC assay. |
The CDC assay combines the biologic therapeutic and its target to evaluate complement activation.
| Materials | Description | Products needed |
|---|---|---|
| Biologic therapeutic + Therapeutic target + NHS | Evaluate if the combination of the therapeutic biologic and target activates the complement system, leading to CDC. Variations of dilutions, concentrations and incubation times should be considered. | NHS: Complement source EIA kits: Complement protein detection (see product list section for specific kit recommendations) |
QuidelOrtho SPG offers dozens of products for measuring and studying the complement system, including ELISAs, multiplex, antibodies, proteins, serum, depleted sera and reagents.
IVD | Complement | ELISA | Antibodies | Proteins | Serum | Donor Testing | POCT | Sample Collection | Instruments
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