Ensuring Robust & Consistent Protein Manufacturing
Proteins are used for diagnostic purposes primarily as antibodies and antigens, although new methods such as nanobodies and antibody mimics have recently seen wider use. They are usually generated in a hybridoma screen, achieved by finding the optimal clone and multiplying that to produce antibodies for large-scale diagnostic purposes e.g. in bioreactors. After purification, several types of modifications are required to optimize the antibody for diagnostic purposes. These can be fluorescent probe-conjugated antibodies that identify target cells using immunofluorescence, radioactive labeling for radio detection, or even enzyme-linked antibodies for assays such as ELISA.
Whether working with diagnostic antibodies on a small or large scale, a key factor that makes life a little easier on the production team is the fact that these antibodies do not need to be clinical grade, since they are only used ex vivo in analysis studies, and not in vivo for any treatments.
Diagnostic Antibodies for Disease Characterization & Monitoring
Diagnostic antibodies are used to generate diagnostic assays and monitor many infectious diseases, for tissue typing and immune assays. Antibodies are also used for the investigation and screening of non-pathogenic diseases such as cancers, and metabolic and hormonal diseases1.
For instance, sometimes acute kidney injury is caused by other underlying diseases, e.g. symptomatic multiple myeloma2, whereby early diagnosis of the kidney injury and determining the cause is crucial in providing the best treatment for the patient. Read about how Celcuity developed the world’s first diagnostic tests that use a patient’s live tumor cells.
Most commonly, diagnostic antibodies are used to identify and for antigenic characterization of the animal disease pathogen, SARS-CoV-19 or coronavirus, responsible for the onset in 2019 of the COVID-19 pandemic3,4. Apart from learning about the pathogen and its method of infection and disease development, antibody-assays (‘quick tests’) can be developed to help control disease spread.
To learn more about the development of therapeutics against diseases, see the therapeutic antibodies page or learn about how two different companies use virus-like particles (VLPs) to develop vaccines: AdaptVac on coronavirus, and PaxVax on adenovirus, hepatitis A, HIV, Zika and chikungunya.
How to Ensure a Consistent Manufacturing Process
Proteins for diagnostic use need to be manufactured in a very robust manner, whereby the end product is always the same and passes the qualification tests necessary for product release. But since the manufacturing procedure uses living cells, which can always behave slightly different from one production run to the next, having precise and robust instruments measuring quality at each in-process checkpoint is crucial.
The NucleoCounter® is the most precise automated cell counter on the market; it has a combined inter-operator/inter-instrument variation of typically 5 – 10%. You can achieve superior performance from a standardized workflow that eliminates human bias in just 30 seconds. The instrument acquires the same robust data between sites and users with every sample.
The DebrisIndex™ parameter measures debris build-up in a culture. Since debris negatively affects downstream filtering and purifications steps, a direct measurement of debris facilitates better process development parameters.
You can obtain identical results with any cell sample, recorded by any user, anywhere in the world.
- Z Siddiqui: Monoclonal Antibodies as Diagnostics; an Appraisal. Indian J Pharm Sci. 2010; 72(1): 12–17.
- F Bridoux, N Leung, M Belmouaz et al.: Management of acute kidney injury in symptomatic multiple myeloma. Kidney Int. 2021; S0085-2538(20)31405-8.
- C Fougeroux, L Goksøyr, M Idorn et al.: Capsid-like particles decorated with the SARS-CoV-2 receptor-binding domain elicit strong virus neutralization activity. Nat Commun. 2021; 12(1):324.
- U Jappe, H Beckert, K-C Bergmann et al.: Biologics for atopic diseases: Indication, side effect management, and new developments. Allergol Select. 2021; 5:1-25.