Immune System Test

Why should I take the Immune System Test?

The immune system is constantly active – otherwise, we would not survive in a world full of pathogens. But in certain situations, our defence systems are weakened or overstrained.

By looking at the number of lymphocytes, you can identify signs of infection and better assess the state of your immune system. For example, there are fewer defence cells present when you have an infection, such as the flu or a cold.

Researchers have discovered an interesting correlation between lymphocyte tests and Covid-19. According to them, you should take an immune system test when you suspect a Covid-19 infection along with a test designed to detect the virus, such as the cerascreen® Coronavirus PCR Test. If the PCR test is positive and the immune system test shows an insufficient number of lymphocytes, the risk of a severe coronavirus infection may be higher.

Talk to your doctor about any abnormal results. Be sure to contact your GP by phone first if you suspect Covid-19.

Who should take the test?

The cerascreen® Immune System Test can provide exciting insights for anyone who wants to learn more about their own health.

It is particularly interesting for people who suspect they have problems with their immune system or whose immune system is frequently challenged by pathogens.

For example, people who have young children or work with children often struggle with infections such as colds. In such cases, it may be worthwhile to check the functioning of the immune system and strengthen it, if necessary.

A weakened immune system can manifest itself through frequent infections, but also, for example, through wounds healing slowly, hair loss, frequent skin irritation and herpes, and frequent fatigue.

How does the test work?

For the immune system test, take a small blood sample from your fingertip using a lancet. Only a few drops of blood are needed for this. Collect the drops on a dry blood card – this way, you only have to take a very small amount of blood, and the sample has a long shelf life.

Send in the sample is free of charge by return envelope to a specialist medical laboratory. The laboratory analyses the proportion of the five tested lymphocytes in the total number of white blood cells.

After the analysis is complete, you will receive a notification to access the results report via logging in on the cerascreen website or the My cerascreen® app.

How long does the analysis take in the laboratory?

Once your sample has arrived at the laboratory, it will be analyzed there by specialists. How long the analysis takes depends on the exact measuring method and the processes in the laboratory.

If the sample is sent on the correct days (Sunday to Tuesday), this makes it easier for the laboratory to adhere to the times.

For the Immune System Test, the laboratory analysis is usually completed within 5 working days after the sample is received in the laboratory.  

When should I take the test?

The results of immune testing are strongly influenced by whether you are healthy at the time of the measurement or have an infection, for example, the flu or a cold.

If your values are normal when healthy, it may be worth keeping another test handy that you can take if symptoms of an illness emerge in the future.

What do the results tell me?

The Immune System Test results report shows you the number of each lymphocyte that the laboratory has detected in your blood.

The results are presented as percentages. They represent the proportion that the respective lymphocyte has in the total number of white blood cells. You are given reference ranges of healthy people between the ages of 18 and 71 with which you compare your values. For example, the normal range for T cells (CD3+) is 11.30 to 33.17 per cent.

Which recommendations will I receive?

If you have lymphocyte values that are significantly outside the reference ranges, we recommend that you contact your doctor.

If values are just outside the reference range, this may indicate that you have a cold or the flu. In this case, another test may be useful to check the values again once the infection has cleared up.

In your results report, you will also receive a whole range of tips and recommendations that you can use to strengthen your immune system in everyday life.

What are lymphocytes?

Lymphocytes are a type of white blood cells (leukocytes). They are among the most important building blocks of the human immune system.

Lymphocytes include various types of T cells, B cells and natural killer cells.

These immune cells have different tasks in the immune system. For example, they ensure that antibodies are produced, slow down the growth of tumour cells and can identify and fight pathogens.

Which lymphocytes are tested?

The laboratory analyses five different lymphocytes. They are all important components of the immune system and have different tasks:

• T cells (CD3+) fight off pathogens and inhibit the growth of cancer cells
• T cells (CD4+), the T helper cells, recognise antigens (proteins of pathogens) and ensure that messenger substances are released that call defence cells into action.
• T cells (CD8+), the cytotoxic T cells, destroy infected or degenerated body cells after antigens have been identified in them.
• B cells (CD19+) are involved in the formation of antibodies.
• NK cells (CD16+ CD56dim), the natural killer cells, eliminate pathogens and cancer cells and kill harmful body cells.

How are lymphocytes and Covid-19 linked?

Many people who suffered from severe Covid-19 infections had strikingly low numbers of lymphocytes in their blood, especially T cells. Chinese researchers found this in studies early on during the coronavirus pandemic.

This is not entirely unusual. Infectious diseases often lead to lymphocytopenia, a low number of lymphocytes. You could say that the infections cause your immune system to use up more of its defence cells. Once the illness has subsided, the number of lymphocytes usually recovers.

But with Covid-19, there is wide variation in how severe lymphocytopenia is. There seems to be a correlation between a low lymphocyte count and the severity of the disease. Some scientists have therefore suggested using lymphocyte levels to identify high-risk patients at an early stage – for example, in hospital. This way, those affected can be monitored more carefully, and the hospital’s resources can be better managed.

How can I strengthen my immune system?

A fully functioning immune system helps prevent you from getting infections and stay healthy in the long term. It therefore always makes sense to support your immune system in everyday life.

Your lifestyle plays an important role in this. The following recommendations will help you keep your immune system strong:

• Have a varied diet: Be careful not to develop nutrient deficiencies. Eat plenty of fruits and vegetables and check your vitamin D levels regularly.
• Exercise regularly: Exercise several times a week and take advantage of opportunities to walk and cycle in your daily routine.
• Get sufficient sleep: Lymphocytes are formed during sleep – a lack of sleep leads to an increased susceptibility to infections.
• Reduce stress: Try to take the pace out of your everyday life when it gets too much. Relaxation techniques such as yoga and meditation can also help.
• Avoid alcohol and nicotine or reduce consumption: The two substances interfere with the formation of immune cells.

You can find more detailed tips on this in your cerascreen® Immune System Test results report.

Why are children under 18 not allowed to take the test?

Our tests are not suitable for underage children and adolescents under the age of 18. Under 18s cannot activate the tests online and therefore cannot receive a test result. We ask that you do not administer the tests to your children either.

Children and adolescents need much closer supervision and counselling regarding medical tests and their interpretation. Testing with lancets and chemicals is not without risk and would need to be closely supervised by guardians. In addition, the reference values we give are always based on adult data. In the case of children, the risk of misinterpreting the results would be very high.

We want to fulfil our responsibility as a provider of medical products and ensure that children and adolescents are not unsettled by measurement results that are difficult for them to interpret. Since we cannot control whether the minors' legal guardians actually consent to the test being carried out and supervise them, we exclude tests for under 18s altogether.

If you are under 18 and have purchased a test, please contact our customer support.

Why does it take up to a week for the sample to reach the lab?

Please bear in mind that your results will not be analyzed in the UK but in Germany. For that reason, it can take up to a week for the sample to arrive at the lab. This does not affect the stability of the samples, as the method we are using is optimized for long transports.

Initially, your sample is sent to our collection center in the UK. From there, it is shipped to our central sample sorting facility in Germany, which then distributes samples to our partner laboratories. Once your sample is analyzed there, you will receive a notification and can access your result online.

Please check your mailbox regularly. We will notify you as soon as your sample is sent, arrives, or is analyzed.