What does HLA mean in a blood test?
HLA-B27 is a specific protein (termed a human leukocyte antigen or HLA) that is found on cell surfaces. The term HLA-B27 is also used to refer to the gene that codes for the HLA-B27 protein. The HLA-B27 test determines the presence or absence of HLA-B27 protein on the surface of a person's white blood cells.
What diseases are associated with HLA?
Molecular interaction: MHC-peptides and autoimmune diseasesRheumatoid arthritis (RA) ... Multiple sclerosis (MS) ... Systemic lupus erythematosus (SLE) ... Type 1 diabetes mellitus (T1D) ... Sjögren's syndrome (SS) ... Celiac disease (CD) ... Ankylosing spondylitis (AS)
What causes HLA?
Human leukocyte antigen (HLA) sensitisation occurs after transfusion of blood products and transplantation. It can also happen spontaneously through cross-sensitisation from infection and pro-inflammatory events.
What does it mean to be HLA negative?
A negative result means you don't have HLA-B27 in your blood. A positive result means HLA-B27 was found in your blood. You may have a higher-than-average risk of certain autoimmune diseases, such as ankylosing spondylitis and reactive arthritis.
Is HLA an autoimmune disease?
Human leukocyte antigen (HLA) is the main genetic factor related to autoimmune diseases, accounting for a half of known genetic predisposition [6].
Is HLA hereditary?
The HLA system is inherited in a Mendelian manner and extensively polymorphic; its recombination rate is low; mutation has not been observed in family studies; and antigen frequencies are known for many different ethnic groups.
Which autoimmune disease is associated with HLA genes?
Strong association between the HLA region and autoimmune disease (AID) has been established for over fifty years. Association of components of the HLA class II encoded HLA-DRB1-DQA1-DQB1 haplotype has been detected with several AIDs, including rheumatoid arthritis, type 1 diabetes and Graves' disease.
What do the HLA testing results show?
Specific HLA genes or antigens are identified during HLA testing to ensure solid organ or hematopoietic stem cell transplant compatibility. The typing result of the recipient is compared to those of the potential donor. Results indicate how many antigens match and how many antigen mismatches are present.
What does high HLA mean?
People with certain HLA antigens are more likely to develop certain autoimmune diseases, such as type I diabetes, ankylosing spondylitis, rheumatoid arthritis, celiac disease, SLE (systemic lupus erythematosus), myasthenia gravis, inclusion body myositis, Sjögren syndrome, and narcolepsy.
How common is HLA antibodies?
The prevalence of any HLA antibody was similar in non-transfused (n=1138) and transfused (n=895) men, 1.0 vs. 1.7% (p=0.16). HLA antibodies were detected in 17.3% of all female donors (n=5834) and in 24.4 % of those with a history of previous pregnancy (n=3992).
Is HLA-B27 positive serious?
What Abnormal Results Mean. A positive test means HLA-B27 is present. It suggests a greater-than-average risk for developing or having certain autoimmune disorders. An autoimmune disorder is a condition that occurs when the immune system mistakenly attacks and destroys healthy body tissue.
Do HLA antibodies go away?
Unfortunately once you have anti-HLA antibodies, they do not go away on their own. Antibodies can be difficult to remove from the body, although different treatments have been tried. Antibody levels can temporarily increase in the setting of infection, vaccination, or transplantation.
What disease has highest incidence of association of HLA?
HLA is the strongest genetic factor for type 1 diabetes (Nerup et al., 1974). Current data suggest that HLA-DQ heterodimers represent the factor of highest risk for islet autoimmunity rather than the onset of hyperglycemia (Graham et al., 2002; Krischer et al., 2015).
What diseases are caused by HLA-B27?
With lower frequency, the presence of the HLA-B27 allele has correlated with inflammatory bowel disease, psoriatic arthritis, and reactive arthritis.
Why does HLA cause autoimmune disease?
The development of protease inhibitors designed to alter the antigen presenting properties of HLA molecules, by blocking the presentation of potentially auto-antigenic peptides, could direct the immune system away from a particular antigenic motif and in turn the autoimmune disease process [37].
How many HLA types does a person have?
There are three general groups of HLA, they are HLA-A,HLA-B and HLA-DR. There are many different specific HLA proteins within each of these three groups.
What Is the HLA System?
The HLA system refers to a group of related genes that play an important role in the immune system. Together, the proteins made from these genes form something called the major histocompatibility complex (MHC). These proteins are attached to almost all of the cells of your body (excluding red blood cells).
Why do people type HLA?
By far, the most common reason for HLA typing is to help determine which people can provide the safest tissue transplants ( solid organ or hematopoietic stem cell transplantation ). 1 Potential tissue recipients must have the typing, as must anyone who might potentially want to donate tissue.
Why do you need to have HLA after a transplant?
Some people may also need to have a component of HLA typing performed after transplant, to see if their body is making antibodies to the transplanted tissue. This might be one sign that organ rejection is taking place, and the transplant may not be a success.
How many chances do siblings have of being HLA identical?
There is also about a one in two chance that siblings will share half of the HLA markers and be a half-match. Because siblings only have a one in four chance of being HLA identical, it’s not uncommon for people not to have anyone in their family that is a close match. 5 .
What is HLA typing?
Tissue Registries. HLA typing is a kind of genetic test used to identify certain individual variations in a person’s immune system. The process is critical for identifying which people can safely donate bone marrow, cord blood, or an organ to a person who needs a transplant. HLA stands for human leukocyte antigen, ...
What happens if you have antibodies against HLA?
If a person already has an antibody against an HLA protein (i.e., if it already is primed to attack a certain color string), it may attack that protein if it is transplanted. This may cause the transplant to fail.
What happens if an immune cell notices an orange protein string?
If an immune cell notices a cell with an orange HLA protein string, it would send off alarm bells. That warns the cell that it might be seeing something potentially dangerous, like a virus. This might trigger the immune system to attack the cell. The HLA system plays an important role in immune defense.
What does it mean if you have a positive HLA-B27?
If you are HLA-B27 positive, then it means that you are at increased risk than others for some autoimmune conditions like reactive arthritis and ankylosing spondylitis. (1, 2) White people are more likely to have a HLA-B27 positive test. (4)
What is the HLA B27 test?
The HLA-B27 test is also done if a person is having a tissue or organ transplant.
Why is the HLA B27 test done?
The HLA-B27 test is done if your doctor suspects you are suffering from autoimmune disease, such as Ankylosing spondylitis. The HLA-B27 test is done to look for the presence of HLA-B27 that is present on the surface of white blood cells. The HLA-B27 are proteins and if you test positive for it, ...
Is there a factor that affects the results of the HLA-B27 test?
There aren’t any particular factors that affect the results of HLA-B27 test.
Are There Any Other Tests That Need To Be Done With The HLA-B27 Test?
After a positive HLA-B27 antigen test, other tests need to be done to confirm the diagnosis of an autoimmune disease and these tests include: C-reactive protein,
Why is the HLA test important?
The HLA test has also been used to identify these diseases. HLAs play an important role in protecting you from infections. But they also make organ transplantation more complex. HLAs are protein markers found on nearly all of your body's cells.
What do my test results mean?
Test results may vary depending on your age, gender, health history, the method used for the test, and other things. Your test results may not mean you have a problem. Ask your healthcare provider what your test results mean for you.
What is this test?
This test checks your blood for antibodies against a cell marker called a human leukocyte antigen (HLA). The test is done if you need an organ transplant, to help find a donor organ that will work in your body. Different forms of the HLA antibody are involved in autoimmune diseases. These are diseases in which the body attacks its own tissues. The HLA test has also been used to identify these diseases.
Why do I need this test?
You may need this test if you need an organ transplant from someone else. if your kidney, lung, or other organ is no longer able to work properly. This test helps give you the best possible chance that the transplant will work well in your body. You may also need this test if your healthcare provider thinks that you have an autoimmune disease.
What will your results show after a transplant?
Your results will show if you have certain types of antibodies that could cause a problem after a transplant. Some people have these antibodies, and some don't. Your results will affect the search process for a transplant.
What can affect your blood test results?
Past pregnancies, blood transfusions, and transplants can affect your results.
How is this test done?
The test is done with a blood sample. A needle is used to draw blood from a vein in your arm or hand.
What is the HLA antibody?
These antibodies are called human leukocyte antigen (HLA) antibodies. They are more common in the blood of people who have had a blood transfusion or those who have been pregnant. Some people may have these antibodies for other reasons as well.
How long does it take for HLA antibodies to come back?
It may take several weeks for your test results to be available. If your blood doesn’t contain the HLA antibodies (a negative test result), you will not be contacted and you can continue donating as you had before. If your blood does contain the HLA antibodies (a positive test result), you will receive a letter in the mail.
Is HLA antibody harmful?
If HLA antibodies are in your blood, they are not harmful to you. These antibodies are your body’s natural response to your baby’s blood if you’ve been pregnant. They also are a natural response to a donor’s blood if you’ve had a transfusion.
What is the normal range for an HLA-B27 test?
The test will indicate either the presence or the absence of HLA-B27, i.e. it will indicate a positive or negative result. The doctor will interpret the results in association with the symptoms, age, the gender of the patient and health history.
How many people test positive for HLA B27?
In general, a significant section of the population ranging around 6 to 8% will test positive for this protein. In some cases, the HLA-B27 protein can cause the immune system to attack the otherwise healthy cells of the body resulting in auto-immune diseases. In terms of statistics, only 10 to 15% of the individuals carrying this protein will end up ...
What is the price of an HLA-B27 test in India?
The price for the test in India ranges between INR 1000 to INR2000 depending on the center and the facilities.
What is the HLA B27 test?
What is the HLA-B27 test? The HLA-B27 is a blood test that is used to determine the level of a particular protein called human leukocyte antigen B27 (HLA-B27), which is also a genetic marker. The protein is an antigen that is found on the surface of white blood cells that are fighting infection in the body.
What are the symptoms of HLA B27?
The following symptoms are generally associated with an auto-immune disorder related to HLA-B27. – Inflammation of urethra accompanied by skin lesions. – Swelling or stiffness of the vertebrae in the spine, neck or in the chest area. – Recurring inflammation and swelling of the middle of the eye.
What is the effect of HLA-B27 on the immune system?
In some cases, it is believed that the similarity between the HLA-B27 antigen and the antigens found on the cellular surface of the invading microorganisms trigger the immune system to act against both the healthy and disease-causing cells.
Is HLA B27 positive for ankylosing spondylitis?
But almost 80-90% of people with ankylosing spondylitis are found to be positive for HLA-B27. It is also to be noted that around 10-20% of patients with proven ankylosing spondylitis will test negative for HLA B27. So the negative results of a test do not indicate that someone is free from the disease. Each person has a distinct combination of HLA ...
What is the purpose of HLA?
Human leukocyte antigens (HLAs) are proteins commonly found on white blood cells. These antigens help your immune system identify the differences between healthy body tissue and foreign substances that may cause infection. Although most HLAs protect your body from harm, HLA-B27 is a specific type of protein that contributes to immune system ...
What does a negative HLA B27 test mean?
A negative test indicates the absence of HLA-B27 in your blood.
What does HLA B27 do to your body?
Although most HLAs protect your body from harm, HLA-B27 is a specific type of protein that contributes to immune system dysfunction. The presence of HLA-B27 on your white blood cells can cause your immune system to attack those otherwise healthy cells. When this occurs, it can result in an autoimmune disease or immune-mediated disease, ...
What is HLA B27 associated with?
Monitoring disease progression. The presence of HLA-B27 is associated with certain autoimmune and immune-mediated diseases, including: ankylosing spondylitis, which causes inflammation of the bones in your spine. reactive arthritis, which causes inflammation of your joints, urethra, and eyes, and sometimes lesions on your skin.
How is the HLA B27 test done?
A healthcare provider in a doctor’s office or a clinical lab administers it. They usually take the blood sample from your arm using a small needle. Your blood is collected in a tube and sent to a lab for analysis.
Can you have HLA B27 in your blood?
Sometimes people with autoimmune disorders don’t have HLA-B27 on their white blood cells. If the test is positive, this means that HLA-B27 is present in your blood. Although a positive result may be cause for concern, the presence of the antigen doesn’t always mean that an autoimmune disorder will develop. Diagnosis of an autoimmune disorder must ...
Is the HLA B27 blood test positive?
The takeaway. The HLA-B27 blood test is one step in the process of diagnosing a potential autoimmu ne disorder . Neither positive nor negative results to the test should be taken as confirmation of whether you have an autoimmune disorder or not.
Purpose of HLA Typing
What Is The HLA System?
- The HLA system is a group of genes that play an important role in the immune system. Together, the proteins these genes make form the major histocompatibility complex(MHC). The proteins are attached to almost all of the cells of your body. Red blood cells are the only cells the proteins are not found on. There are many possible variations in these ...
The Process of HLA Typing
- HLA typing looks at the HLA genes that you have inherited. It might help to think about them as colored strings. There are a number of different HLA genes and different variations of these genes. That means there are many possible color combinations. Together, the variations make up your specific HLA type.1
Interpreting Results
- The results from HLA typing are not likely to mean much to you on their own. It can be hard to make sense of them because the HLA proteins have very technical names. However, your healthcare provider may talk to you about how your HLA type compares to that of a potential donor. For example, if your sibling needs a stem cell transplant, the test can tell you if the two of …
HLA Typing and Tissue Registries
- Information about your HLA type is included in databases that link potential donors to recipients. For example, the United Network of Organ Sharing determines who gets organs from deceased donors in the United States. It uses information about donors’ and recipients’ HLA types to calculate the best matches for these organs. It is one of many factors that determine who receiv…
Summary
- HLA (human leukocyte antigen) typing is used to figure out who will be a good match for a person who needs a transplant. People who need stem cells or solid organs for a transplant do better when they "match up" in certain ways with donors. One way is their HLA type, which looks at genes and proteins in the immune system. HLA typing can also be used after a transplant has been do…
A Word from Verywell
- If you are learning about HLA typing because you or a loved one needs a transplant, you might feel overwhelmed by all the information. It's important to ask your healthcare provider questions to make sure that you understand how the testing works. HLA typing is an important step for people who need transplants. Finding a good match gives them the best chance of a successful transpl…