Enzyme-linked immunosorbent assay (ELISA) is an essential tool in medicine and pharmacy that has become the gold standard of immunoassays. This highly sensitive immunological test detects and quantifies various substances such as antibodies, antigens, proteins, glycoproteins, and hormones.
ELISA tests are sometimes called sandwich assays because the measured substance is “sandwiched” between two antibodies. One antibody acts as a trap, while the other helps detect the target substance.
This post examines the role of ELISA assay in diagnosing various medical conditions and its role in pharmacy or developmental drug research.
ELISA Assay Applications In Medicine
ELISA assays play crucial roles in medicine, helping diagnose, screen, and monitor various medical conditions. Its high sensitivity and ability to detect and quantify various substances make it an invaluable tool for healthcare professionals. ELISA tests are often used as a screening tool before more in-depth tests are ordered.
Applications of ELISA assay in medicine are:
ELISA tests detect specific antibodies or antigens in a patient’s blood or other biological samples. Some of the conditions that an ELISA test can help diagnose include:
- HIV, which causes AIDS
- Lyme disease
- Pernicious anaemia
- Rocky Mountain spotted fever
- Squamous cell carcinoma
- Varicella-zoster virus, which causes chickenpox and shingles
- Zika virus
ELISA assays are used as an initial screening tool for various conditions listed above before conducting more specific confirmatory tests. It helps healthcare professionals identify potential cases early and initiate appropriate treatment or interventions to prevent them from escalating.
In HIV screening, the ELISA test detects HIV antibodies in a patient’s blood sample. If the test results indicate a positive or reactive result, it suggests the presence of HIV antibodies, and additional testing is warranted to confirm the diagnosis.
The Total Antibody ELISA Test for COVID-19 is designed to detect the presence of antibodies against the virus (SARS-CoV-2) in a person’s blood sample. The test uses a lab-made version of the virus’s spike protein and follows a two-step process.
- Monitoring Disease Progression
To monitor disease progression using ELISA tests, healthcare professionals will collect blood or other biological samples from the patient at different time points during the disease or treatment. By comparing the levels of specific antibodies, antigens, or biomarkers over time, they can gain insights into how the condition evolves, how the patient responds to the treatment, and identify potential relapses (e.g. cancer). This will enable doctors to make informed decisions regarding treatment adjustments and further interventions.
This test can provide insights into the progression of the infection and the patient’s response to antiretroviral therapy.
- Autoimmune Diseases
In conditions like rheumatoid arthritis or lupus, ELISA tests can measure the levels of specific autoantibodies or inflammatory markers. An example is the C-reactive protein (CRP), which can help assess disease activity and response to treatment.
ELISA tests can monitor allergen-specific IgE antibodies in a patient’s blood, helping to evaluate the effectiveness of allergen immunotherapy or other allergy management strategies.
- Infectious Diseases
In chronic infections, such as hepatitis B or C, ELISA tests can measure viral antigens or specific antibodies to track the course of the illness and evaluate the patient’s response to antiviral therapy.
ELISA tests can monitor the levels of specific tumour markers or cancer-related proteins in the blood, which can help assess disease progression, response to treatment, or the risk of recurrence.
- Assessing Immune System Function
ELISA assays can help determine the levels of specific immune markers in the body, providing insights into the immune system’s overall function and detecting abnormalities before aggravating.
- Therapeutic Drug Monitoring
In some cases, ELISA assays are used to measure drug concentrations in patients’ blood to ensure that the drug remains within the therapeutic range, reducing the risk of side effects or treatment failure.
ELISA Assay Applications In Pharmacy And Drug Development
ELISA tests play an essential role in pharmacy and drug development by helping researchers study and understand how new drugs work, how safe they are, and how effective they can be.
Here are some important ways ELISA tests contribute to these processes:
1. It Aids Drug Discovery
ELISA tests help researchers identify and measure specific proteins or other substances (like antigens and antibodies) that can be targeted for new drugs.
2. It Determines How Drugs Work And Toxicity
ELISA tests are used to understand how drugs interact with the body and how the body processes them during absorption, distribution, metabolism, and excretion. This is crucial for developing safe and effective medications. By measuring specific markers related to toxicity or side effects, ELISA tests help researchers evaluate the safety of new drugs and determine appropriate dosages.
3. It Is Used In Testing Immune Response
In the case of biological drugs, such as monoclonal antibodies, ELISA tests can be used to assess the body’s immune response to the drug. This information is vital for understanding how the medication will affect the patient and ensuring its safety and effectiveness.
4. It Is Valuable In Vaccine Development
ELISA tests play a crucial role in evaluating the efficacy of new vaccines by measuring the immune response, such as the presence and levels of specific antibodies, following vaccination.
5. It Is Useful In Quality Control
ELISA tests can be used to ensure that drug products meet quality standards, checking for consistency and the presence of active ingredients or impurities.
An ELISA assay is used to identify conditions that trigger immune systems to produce antibodies. Some diseases are difficult to detect through other methods like swab tests, making ELISA blood tests particularly valuable in identifying signs of infection or disease. It helps not only with diagnosing but also helps with screening for it and monitoring its development over time.
Also, ELISA has various roles in discovering, developing, and monitoring efficacy and toxic levels of drugs and vaccines, making it a vital tool in modern medicine and pharmacy. Considering all these, it’s safe to say that ELISA is vital for medicine and pharmacy.