VEI Check · NK Cell Activity

Seeing how immune cells respond
in measurable numbers

The NK cell (natural killer cell) activity test is a blood test that measures how strongly the NK cells in your blood respond to a stimulus. It does not diagnose any specific disease. It is a reference marker we read together with your history, symptoms and other test results to look at your current status.

VEI Clinic, Gangnam — VEI Check · NK Cell Activity

What the Test Is

Results are often reported as the amount of interferon gamma (IFN-γ) that NK cells release after a standardized stimulus, and the exact method depends on the assay.

We do not judge your health from this test alone. It is one piece of information about cell-mediated immune activity, interpreted together with your history, symptoms and other tests.

Who This Is For

People who want a baseline of NK cell activity and to track changes over time
People who want to check their current status after illness, major stress or lifestyle changes
People who need reference information alongside an existing treatment plan (in consultation with their care team)

Factors That Can Affect Results

These factors can change the results, so the specialist reviews test timing and your medications together.

Acute infection, lack of sleep, heavy stress, dehydration
Recent intense exercise or alcohol
Certain medications and supplements, such as steroids and immunomodulators

Before Your Test

A morning blood draw is preferred when possible
Avoid alcohol for 24 hours and intense exercise for 12 to 24 hours before the test
Come well hydrated. Some assays require about 8 hours of fasting, which we explain case by case
Please bring a list of your medications and supplements
Let us know about any recent infection or vaccination

Visit Flow

Results usually take about 3 to 7 business days. We explain the reference range, factors that may have affected the result and whether retesting makes sense.

Consultation: we review your symptoms, goals and medications
The blood draw takes only a few minutes
Related tests are added when needed
We explain the results and guide you on lifestyle care and next steps

How VEI Clinic Works and Precautions

An internal medicine specialist decides whether and when to test after your consultation. What the results mean can vary from person to person, and the specialist decides after your consultation whether further care is needed.

This test is not an emergency service. If you have chest pain, severe shortness of breath, heavy bleeding, confusion, signs of stroke or a high fever with dehydration, call 119 or go to an emergency room.

FAQ

Frequently asked questions

Can this test tell me whether my immunity is good or poor?

It is one reference marker of NK cell response. We do not judge from this result alone, and interpret it together with your history, symptoms and other tests.

What if my result is low?

We first look at factors that can affect the result, such as sleep, stress or a recent infection. If needed, we discuss retesting under suitable conditions.

Do I need to fast?

Some assays require about 8 hours of fasting, and we will let you know when you book.

When will my results be ready?

Usually in about 3 to 7 business days, depending on the assay and the lab.