CD56
Private CD56 blood test in London for £136, measuring one natural killer cell-associated marker with results expected in around 1 business day.
Turnaround time
1 business day
Biomarkers count
1
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Overview of the CD56 Blood Test
The CD56 blood test measures CD56, a cell-surface marker strongly associated with natural killer cells, also known as NK cells.
The test contains 1 biomarker: CD56.
CD56 is also known as neural cell adhesion molecule, or NCAM.
Natural killer cells are specialised lymphocytes that form part of the innate immune system.
Unlike conventional T and B lymphocytes, NK cells can recognise and respond to selected infected or abnormal cells without requiring the same type of prior antigen-specific activation.
They contribute to immune surveillance and can release cytotoxic molecules that help destroy selected virus-infected or abnormal cells.
CD56 is expressed on most natural killer cells, although it is not completely specific to NK cells.
Small populations of T lymphocytes and other immune cells can also express CD56.
The marker is typically assessed using specialist immunophenotyping techniques such as flow cytometry, which distinguishes cells according to proteins present on their surface.
CD56 testing can provide information about the number or proportion of CD56-expressing cells within the blood.
It is important to distinguish cell quantity from cell function.
A CD56 measurement does not directly determine how effectively NK cells can recognise or kill target cells.
Functional NK-cell investigations require different laboratory methods.
CD56 is therefore most informative when interpreted alongside other immune-cell markers, particularly CD3, CD16, broader Lymphocyte Subsets and the total lymphocyte count.
An abnormal CD56 result does not independently diagnose an immune deficiency, autoimmune disease or another specific disorder.
What Does the CD56 Blood Test Check?
This test measures 1 biomarker.
CD56
Measures a surface marker expressed predominantly on natural killer cells and on selected other lymphocyte populations, supporting specialist assessment of cellular immune composition.
Who May Benefit From the CD56 Blood Test?
CD56 measurement is generally most useful during a specialist immunology or immune-cell assessment.
People undergoing natural killer cell assessment - CD56 is one of the principal markers used to identify NK-cell populations.
People with previously abnormal Lymphocyte Subsets - Individual markers can provide additional information about which immune-cell populations are altered.
People with recurrent or unusual infections undergoing specialist investigation - More detailed immunophenotyping may be appropriate when an immune deficiency is suspected.
People with unexplained lymphopenia - Flow-cytometry markers can help determine which lymphocyte populations account for a reduced total count.
People receiving immune-modifying treatment - Selected therapies can significantly alter immune-cell populations.
People undergoing haematological or immunological monitoring - CD56 may contribute to specialist immune phenotyping.
People with a previous abnormal CD56 result - Repeat testing can determine whether a change persists over time.
People requiring more detail than a Full Blood Count provides - A standard FBC measures total lymphocytes but does not identify specific NK-cell-associated markers.
People specifically advised to obtain CD56 testing - The test is most clinically meaningful when requested for a defined immunological question.
How to Prepare
Do not stop immune-modifying treatment solely to change a CD56 result.
For serial monitoring, testing under reasonably similar clinical conditions can make changes easier to interpret.
Symptoms and Reasons to Consider the CD56 Blood Test
There is no symptom pattern specific to an abnormal CD56 result. Testing is usually considered because of recurrent infections, abnormal immune results or specialist monitoring.
Recurrent infections requiring further investigation - Repeated infection can occasionally prompt detailed immune-cell assessment.
Unusually severe infections - Significant or atypical infections may warrant broader immunology testing when clinically appropriate.
A previous low lymphocyte count - Flow cytometry can provide more detailed information about individual lymphocyte populations.
An abnormal previous Lymphocyte Subset result - CD56 measurement can help further characterise natural killer cell-associated populations.
Monitoring during immune-modifying treatment - Some medicines can alter lymphocyte subsets and may require specialist follow-up.
Persistent immune-related concerns under specialist care - CD56 may be included within a broader cellular immune investigation.
A known immunological condition requiring monitoring - Repeat immune-cell phenotyping can provide information about changes over time.
A family history of selected immune disorders where specialist testing has been advised - Targeted immune investigations may occasionally be appropriate.
Recurrent infections and fatigue have many common causes and should not be attributed to an abnormal CD56 result without broader clinical assessment.
CD56 measurement provides information about an immune-cell marker but does not diagnose an immune disorder or directly measure NK-cell killing ability.
How to Book Your CD56 Blood Test in London
CD56 testing requires an appropriate blood specimen for specialist cellular analysis.
Choose the CD56
Select the individual CD56 blood test online.
Select your sample collection option
Choose an appropriate in-clinic or professional home or hotel collection option capable of meeting cellular sample requirements.
Attend your appointment
A trained healthcare professional collects the venous blood specimen.
Laboratory analysis
Your sample undergoes specialist immunophenotyping for CD56 expression.
Receive your results securely
Your authorised result is delivered securely and can be reviewed with a GP, immunologist or other relevant specialist.
When Will I Receive My Results?
The current expected turnaround for CD56 is approximately 1 business day after your sample reaches the laboratory.
Although CD56 is a specialist immune-cell marker, the laboratory can generally complete the analysis rapidly when the sample is received in suitable condition.
Cellular specimens are more time-sensitive than many routine serum tests, which means correct transport and prompt laboratory receipt are particularly important.
Once analysis, quality control and authorisation are complete, your report is released securely.
Occasionally, sample viability, technical quality or the need for repeat flow-cytometry analysis may extend reporting beyond the usual 1-business-day timeframe.
Understanding Your Results
The report may express CD56 according to the laboratory methodology, such as an absolute cell number, percentage of lymphocytes or another flow-cytometric measure.
A reduced CD56-associated population can occur in several different clinical settings.
It does not by itself prove that NK-cell function is impaired.
Likewise, an increased result can reflect altered immune-cell distribution, immune activation or selected haematological conditions and is not diagnostic of one specific disease.
CD56 is also present on some T cells, meaning that it is not an entirely NK-cell-specific marker.
The result is therefore best interpreted alongside CD3, CD16, other Lymphocyte Subsets, the total lymphocyte count, age, medication and clinical history.
A normal CD56 result does not exclude every immune disorder.
An abnormal result does not automatically confirm an immune deficiency.
Where actual natural-killer-cell activity is the concern, specialist functional testing may be required because CD56 measurement alone assesses phenotype rather than cytotoxic function.
Why Book With London Blood Tests?
Private CD56 testing in London - Access specialist immune-cell marker testing privately.
Natural killer cell-associated assessment - CD56 provides information about an important innate immune-cell population.
Specialist immunophenotyping - Cellular analysis can provide detail beyond a routine Full Blood Count.
Useful alongside Lymphocyte Subsets - Additional markers can provide a broader picture of immune-cell composition.
Appropriate for specialist monitoring - Repeat testing can support selected immunology pathways.
Fast results - Current turnaround is approximately 1 business day after laboratory receipt.
Secure reporting - Receive your authorised immune-cell result securely.
Clear pricing - The CD56 blood test costs £136.
Private CD56 Blood Test in London
London Blood Tests provides private CD56 blood testing in London for people requiring specialist assessment of a natural killer cell-associated immune marker.
The test costs £136 and measures one biomarker: CD56.
Results are expected approximately 1 business day after laboratory receipt.
CD56 provides phenotypic information about CD56-expressing immune cells but should not be interpreted as a direct standalone measurement of natural killer cell function.