Lyme disease can be challenging to diagnose in some cases because of the way it affects the body. Initially, people may develop flu-like symptoms without realizing they have contracted Lyme disease. If that occurs, the bacterial infection will continue to take hold within the body, causing further health issues (acute vs chronic Lyme differ in the problems they may cause).
People who know they have Lyme disease early on can take a course of antibiotics, and there’s a good chance this will rid the body of bacteria. That said, no two cases of Lyme disease are ever the same. The infection can progress at different stages depending on how long ago a person contracted it. Many times, the plethora of symptoms that develop because of Lyme disease mimic other health disorders and conditions. Called the “great imitator,” and sometimes undetectable by early signs alone, Lyme disease requires new testing is needed to ensure that when a person contracts it, they can be diagnosed and treated quickly and effectively.
One specific test, the ELISpot test, can be used in the diagnostic process for Lyme disease. But what is an ELISpot test, and can it detect Lyme disease at all stages? Let’s investigate.
What is an ELISpot test?
The ELISpot test is an enzyme-linked immunosorbent spot. It’s a form of highly flexible assay test that utilizes antibodies and enzymes to measure how much of a specific substance can be found within the testing solution.
In response to an infection, the immune system creates antibodies – blood proteins that respond to particular antigens, or toxins, that set off alarm bells. When an antibody is created to combat a specific antigen, it seeks it out and aims to destroy it to protect the body from harm. During an ELISpot test, lab technicians look for antibodies linked to specific enzymes, which are proteins that regulate chemical reactions within the body.
Cytokines, the small proteins involved in the cell signaling process, help the ELISpot test work effectively. These proteins are secreted by cells in the immune system, and higher levels indicate infection. When the test is being conducted, researchers can look for cytokine-secreting cells, the number of antigen-specific cells, or the activation of immune cells to let them know how immunity responds to that specific pathogen.
When do you use ELISpot?
The ELISpot test is used to monitor the immune system. It does this in a couple of ways. The first has to do with infection. When a pathogen, such as a virus or bacteria, enters the body, the immune system is alerted to the threat. That alert system sets off a chain reaction in the body, producing specific immune cells that learn to recognize a particular pathogen (these cells are the antibodies mentioned above).
Using Lyme disease as an example: the immune system gets into high gear when Lyme bacteria enter the body and start to cause infection in the cells. The affected cells can then be used by the ELISpot test to determine whether an infection is occurring.
A similar process uses the ELISpot test to measure vaccine efficacy and how the body responds to vaccines. When a person receives a vaccine, it sets off another chain reaction in the immune system designed to give immune cells a preview of what’s possibly to come. Essentially, the vaccine tricks the body into creating antigen-specific cells in response to an infection the body doesn’t yet have. This makes it easier for the immune cells to fight off a virus or other pathogen if the body does contract it down the road. The ELISpot test measures the antibodies linked to enzymes in both situations to determine how the immune system responds.
Other possible uses for the ELISpot test include:
- Checking for allergy responses
- Transplant diagnostics
If the immune system is activated, the ELISpot can help to determine exactly what actions it’s taking.
How do the ELISpot results work in acute vs. chronic Lyme disease?
In Lyme disease, ELISpot results can help determine the levels of immune activity in the body in response to the infection. However, it’s not always that straightforward.
This highly sensitive test looks for T-cells that have reacted to the bacteria that causes Lyme disease, even if the levels are incredibly low. For example, the infection may go dormant in the body at some point; when that happens, there is no immune response to investigate. Because of the ever-changing levels of activated T-cells, ELISpot results will differ throughout the course of the disease.
The ELISpot will be most helpful in cases of Lyme disease when the infection response in the body is at its highest. That means that, regardless of whether it is acute or chronic, a Lyme infection will be detectable with an ELISpot if there is any T-cell activity.
This can help at both the acute and chronic stages because, during the acute phase, it can determine that a person has an active Lyme disease infection. If someone develops the symptoms of chronic Lyme disease even after treatment, they may be unsure whether they have contracted some other illness or developed a disease, but the ELISpot test can determine if the bacterial infection has reactivated within the body.
The ELISpot test is an added diagnostic tool that, when used effectively, can help determine if a person has an active Lyme disease infection, regardless of the stage of illness.
Featured image by Nguyen Hiep on Unsplash