Today, advanced medical research and cutting-edge molecular diagnostic technology may effectively regulate, treat, and even cure a wide range of fatal diseases. Among these is the Human Immunodeficiency Virus (HIV), which, as the name implies, targets our immune system. When left untreated, HIV turns into AIDS, a lethal disease (we expose this misconception in one of our previous articles).
Regular testing and early diagnosis increase the likelihood of preventing and treating HIV so that it does not progress to AIDS. Early HIV detection is critical because the virus is highly transmissible during the first stage (Acute HIV infection).
For many labs, the Western Blot and ELISA tests have been the gold standard of HIV testing. Today, we’ll look at these two lab testing methods and see which one is the most accurate for HIV testing.
But before that, here is a quick recap of what we do.
Helvetica Health Care (HHC) is a trusted name in the supply of high-quality and essential lab testing products. We are known for the ZeptoMetrix WESTERN BLOT for in vitro detection of antibodies to SIV (Simian Immunodeficiency Virus, the lentivirus most closely related to Human HIV) in serum or plasma, available in 10 or 30-strip kit formats.
We also provide a wide range of ELISA kits ready to use with break-apart wells that include
• The RETROTEK™ range is designed for the detection and quantitation of retroviral antigens from the retroviruses HIV-1, SIV and HTLV found in cell culture, serum, plasma or other biological fluids
• IMMUNOTEK™ kits can detect and quantify various immunoglobulins from many species, including Humans, Chicken, Cow, Goat, Rabbit, Rat and Mouse. We also provide HHV-6 IgG antibody and KSHV/HHV8 IgG antibody ELISA kits.
Now that we have established our expertise let’s look at the two commonly applied HIV testing methods – ELISA and Western Blot.
What Is Elisa?
The enzyme-linked immunosorbent assay, or ELISA, is a popular and inexpensive test for studying antibodies, antigens, proteins, and glycoproteins. It’s a popular choice for immune testing due to its high sensitivity and simplicity. ELISAs are frequently used by researchers to determine whether certain proteins are present in samples such as urine, blood serum, or cell cultures. HIV antibodies and antigens can be detected using ELISAs in blood samples.
The immune system produces antibodies, which aid our bodies in fighting disease. When foreign bodies, such as viruses, enter the body, our immune system responds by producing antibodies. Antigens, on the other hand, are any foreign material that the body encounters and to which the immune system responds.
What Is Western Blot?
Western blotting, also known as protein immunoblotting, is a common cell and molecular biology technique. It is used to determine whether certain proteins are present in a sample, as well as their size and relative strength, which can indicate the stage of HIV infection.
How Does Elisa HIV Testing Work?
ELISAs are commonly used to detect HIV antibodies by looking for proteins produced by the body in response to the virus. The viral protein antigen will be included in a cassette with the blood sample. If the blood contains HIV antibodies, they will bind to the antigen and change the colour of the cassette’s contents. This extremely sensitive test was the first widely used HIV test.
ELISAs, which are highly sensitive, were the first and are still the most widely used HIV diagnostic technique. ELISA tests are typically performed in 96 well test plates, which means that a large number of tests can be performed in each run, making it quick and cost effective. ELISA tests lend themselves well to automation, and many laboratories now use fully automated, robotic systems.
What Is The Role Of The Western Blotting Technique In Hiv Testing?
Typically, labs would run the Western blotting procedure following an ELISA to confirm a positive test result. However, since alternative tests have become more trustworthy and provide a speedier diagnosis, the Western blot test is less often recommended.
In this technique, the blood samples are taken in the same way as the ELISA tests, but the sample collected is then divided by an electrical current and transferred to blotting paper. Here, adding an enzyme results in colour alterations that indicate the presence of HIV antibodies.
As we established earlier, the detection of HIV in the first or the acute infection stage is critical as there lies a higher risk of HIV transmission from one individual to another during this period compared to confirmed HIV patients. Despite being a gold standard for molecular diagnostics in the past, Western blotting is less often recommended due to the following limitations:
- Inability to detect acute infection
- Potential misclassification of HIV-2 infection as an HIV-1 infection
- Delayed lab processes due to the need for batches or the need to outsource samples for testing
- Possibility of false-negative or inconclusive outcomes in acute and early stages of seroconversion.
- Difficulty in interpreting results.
Elisa vs Western Blotting for HIV Testing
When comparing ELISA and Western Blotting for HIV testing, ELISA assays are far superior to Western blotting testing in terms of blood screening, in terms of cost, efficiency and practicality.
With the number of diseases on the rise, one cannot stress more on the importance of testing which is the first step towards efficient health management of patients. If you are a lab or a lab technician, let us help you make your lab processes more accurate and efficient.
Call us now to find out more about our products.
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