What is Diagnostic Immunology?

The COVID-19 pandemic has forced health organisations around the world to spearhead new ways to protect global citizens. Diagnostic immunology has played an important role, gaining traction for its potential to treat and prevent both infectious and immune-driven diseases, including rheumatoid arthritis, psoriasis and Crohn's disease. Also known as immunodiagnostics, the method uses antigen-antibody reactions to detect disease, as well as develop solutions for treatment and prevention.

The importance of antibodies

Diagnostic immunology is heavily reliant on the collection of antibodies. Used as laboratory reagents, these blood proteins are produced when the body attempts to fight off a unique antigen. When activated, the Y-shaped proteins bind to foreign substances such as a bacteria or virus. If successful, they then destroy these substances.

"They're released from the cell and they go out and hunt," explains Dr. Warner Greene, director of the Centre for HIV Cure Research at the Gladstone Institutes in San Francisco. This “search and destroy” action plays a critical role in helping the body fight off alien antigens and remain healthy.

Antibodies are especially important when studying infectious diseases as they offer scientists insight into how a virus or disease works, as well as how the body fights it off.

Embracing new technologies

Over the past decade diagnostic immunology has significantly advanced thanks to the development of automated technologies and methods. This includes the use of next-generation instrumentation such as flow cell sorters, which are used to analyse live cells that have been stained with fluorescent antibodies.

Enzyme-amplification has helped to enhance the sensitivity of immunoassays, with technology such as Chemiluminescence ELISAs using a microplate reader to measure luminescence and record the intensity of light reaction between an enzyme label and a substrate.

Leveraging automated methods

Miniaturisation, the use of microtiter plates to document samples, has allowed scientists to easily save and store reagents which can then be used on future research projects. Automation and the introduction of standardised procedures has also helped to streamline laboratories and improve efficiency in immunological settings.

New molecular methods, including polymerase chain reactions (PCR) that allow scientists to amplify a tiny sample of DNA into a sample large enough to study in detail, have also revolutionised diagnostic immunology and played a critical role in developing the COVID-19 vaccine.

While the rollout of coronavirus vaccines has sparked hope of a global recovery, pressing questions remain over the initial cause of the deadly virus which has now claimed more than 3 million lives. Scientists at the Francis Crick Institute have been tracking the evolutionary path of SARS-CoV-2, with a focus on how the virus may have leaped from bats to pangolins, scale-covered mammals found in Asia and Sub-Saharan Africa. The similarities between SARS-CoV-2 and a pangolin coronavirus are explored further in ‘Could Pangolins cause Coronavirus Infections in Humans?