Blood Groups, Blood Typing and Blood Transfusions Blood Groups, Blood Typing and Blood Transfusions The discovery of blood groups Experiments with blood transfusions, the transfer of blood or blood components into a person's blood stream, have been carried out for hundreds of years. Many patients have died and it was not until 1901, when the Austrian Karl Landsteiner discovered human blood groups, that blood transfusions became safer. Mixing blood from two individuals can lead to blood clumping or agglutination. The clumped red cells can crack and cause toxic reactions. This can have fatal consequences. Karl Landsteiner discovered that blood clumping was an immunological reaction which occurs when the receiver of a blood transfusion has antibodies against the donor blood cells. Karl Landsteiner's work made it possible to determine blood groups and thus paved the way for blood transfusions to be carried out safely. For this discovery he was awarded the Nobel Prize in Physiology or Medicine in 1930. What is blood made up of? An adult human has about 4–6 liters of blood circulating in the body. Among other things, blood transports oxygen to various parts of the body.

Blood consists of several types of cells floating around in a fluid called plasma. The red blood cells contain hemoglobin, a protein that binds oxygen. Red blood cells transport oxygen to, and remove carbon dioxide from, the body tissues. The white blood cells fight infection. The platelets help the blood to clot, if you get a wound for example. The plasma contains salts and various kinds of proteins. What are the different blood groups? The differences in human blood are due to the presence or absence of certain protein molecules called antigens and antibodies. The antigens are located on the surface of the red blood cells and the antibodies are in the blood plasma. Individuals have different types and combinations of these molecules. The blood group you belong to depends on what you have inherited from your parents. There are more than 20 genetically determined blood group systems known today, but the AB0 and Rh systems are the most important ones used for blood transfusions. Not all blood groups are compatible with each other. Mixing incompatible blood groups leads to blood clumping or agglutination, which is dangerous for individuals.

Nobel Laureate Karl Landsteiner was involved in the discovery of both the AB0 blood group (in 1901) and Rh blood group (in 1937). AB0 blood grouping system According to the AB0 blood group system there are four different kinds of blood groups: A, B, AB or 0 (null). Blood group A If you belong to the blood group A, you have A antigens on the surface of your red blood cells and B antibodies in your blood plasma. Blood group B If you belong to the blood group B, you have B antigens on the surface of your red blood cells and A antibodies in your blood plasma. Blood group AB If you belong to the blood group AB, you have both A and B antigens on the surface of your red blood cells and no A or B antibodies at all in your blood plasma. Blood group 0 If you belong to the blood group 0 (null), you have neither A or B antigens on the surface of your red blood cells but you have both A and B antibodies in your blood plasma. Rh factor blood grouping system Many people also have a so called Rh factor on the red blood cell's surface.

This is also an antigen and those who have it are called Rh+. Those who haven't are called Rh-. A person with Rh- blood does not have Rh antibodies naturally in the blood plasma (as one can have A or B antibodies, for instance). But a person with Rh- blood can develop Rh antibodies in the blood plasma if he or she receives blood from a person with Rh+ blood, whose Rh antigens can trigger the production of Rh antibodies. A person with Rh+ blood can receive blood from a person with Rh- blood without any problems. Blood group notation According to above blood grouping systems, you can belong to either of following 8 blood groups: A Rh+ Do you know which blood group you belong to? Blood typing – how do you find out to which blood group someone belongs? 1. You mix the blood with three different reagents including either of the three different antibodies, A, B or Rh antibodies. 2. Then you take a look at what has happened. In which mixtures has agglutination occurred? The agglutination indicates that the blood has reacted with a certain antibody and therefore is not compatible with blood containing that kind of antibody.

If the blood does not agglutinate, it indicates that the blood does not have the antigens binding the special antibody in the reagent. 3. If you know which antigens are in the person's blood, it's easy to figure out which blood group he or she belongs to! A person with A+ blood receives B+ blood. The B antibodies (yellow) in the A+ blood attack the foreign red blood cells by binding to them. The B antibodies in the A+ blood bind the antigens in the B+ blood and agglutination occurs. This is dangerous because the agglutinated red blood cells break after a while and their contents leak out and become toxic. What happens when blood clumps or agglutinates? For a blood transfusion to be successful, AB0 and Rh blood groups must be compatible between the donor blood and the patient blood. If they are not, the red blood cells from the donated blood will clump or agglutinate. The agglutinated red cells can clog blood vessels and stop the circulation of the blood to various parts of the body. The agglutinated red blood cells also crack and its contents leak out in the body.

The red blood cells contain hemoglobin which becomes toxic when outside the cell. This can have fatal consequences for the patient. The A antigen and the A antibodies can bind to each other in the same way that the B antigens can bind to the B antibodies. This is what would happen if, for instance, a B blood person receives blood from an A blood person. The red blood cells will be linked together, like bunches of grapes, by the antibodies. As mentioned earlier, this clumping could lead to death. Blood transfusions – who can receive blood from whom? Of course you can always give A blood to persons with blood group A, B blood to a person with blood group B and so on. But in some cases you can receive blood with another type of blood group, or donate blood to a person with another kind of blood group. The transfusion will work if a person who is going to receive blood has a blood group that doesn't have any antibodies against the donor blood's antigens. But if a person who is going to receive blood has antibodies matching the donor blood's antigens, the red blood cells in the donated blood will clump.

People with blood group 0 Rh - are called "universal donors" and people with blood group AB Rh+ are called "universal receivers." Rh+ blood can never be given to someone with Rh - blood, but the other way around works. For example, 0 Rh+ blood can not be given to someone with the blood type AB Rh -. Blood Types: A, B, AB and O A, B, AB and O Blood Types. Steve Dunwell / Getty Images Blood transfusions can save lives, especially in patients with shock . However, you can't just go hooking up intravenous lines between any two people willy-nilly. Patients' blood comes in multiple blood types and different types can be less compatible than Apple and Android. The most basic blood typing is to categorize blood based on its genetic makeup and a protein antigen that will be present on the outside of the red blood cells. This is known in the medical community as the ABO system and it uses markers for two antigens. ABO Groups There are four basic blood types in the ABO typing system: Type A blood has the Group A antigens and makes antibodies to fight Group B blood. Type B blood has the Group B antigens and makes antibodies to fight Group A blood.

Type AB blood has both Groups A and B antigens, but doesn't make antibodies for either one. Type O blood doesn't have either type of antigen. Donating or receiving blood is complicated by the fact that there are four types of blood. Type O blood, since it doesn't have antibodies or antigens for either type, can be donated to recipients with all four types of blood. Type AB, on the other hand, since it has both A and B antigens and also does not create antibodies for either antigen, can receive blood from all four types, but can only donate to other AB recipients. But, wait! There's more! There's another antigen present on red blood cells that can affect how nice a recipient's blood is to the donor's blood. It's called the Rhesus factor (also known as the Rh factor). 2 Rh Factor Besides the ABO typing system, there are other proteins in the blood that can affect compatibility between a donor and a recipient. The most common is known as the Rhesus factor or the Rh factor. Named for the Rhesus monkeys where it was first discovered (and the first test was developed), Rh factor refers to a protein antigen that can live on the red blood cells.

Those who have the protein are known as Rh positive and those who do not have the protein are known as Rh negative. Rh Antibodies Antibodies will be created to fight the protein in recipients who do not have the proteins in their blood naturally. So a patient with Rh- blood cannot receive a transfusion from a donor with Rh+ blood because the recipient's body will attack the Rh+ blood on contact. Donating and Receiving Previously, we discussed how a patient with Type O blood can receive A, B or AB types through transfusion. Taking into account Rh factor means that O negative blood can theoretically be transfused to any type of patient. Type O- blood is known as the universal donor. AB+ blood, on the other hand, is blood with all the proteins already in it. AB+ patients are known as universal recipients because their bodies will accept all types of blood. 3 What Does "Type & Cross" Mean? Doctors on TV say it all the time: "Nurse, I need you to type and cross the patient." You probably know that it has something to do with blood, but what does it really mean? First, you ought to know that "type & cross" is short for type and cross match.

It refers to tests that blood typically goes through before a transfusion. Typing As we discussed, blood types are based on several different kinds of proteins and antibodies that can be present in any individual's blood. In the terminology, ​type simply refers to the testing process to determine a patient's blood type. Cross Matching Just because the tests all match up and the patients appear to have compatible blood types doesn't mean a transfusion will always work. Cross matching is a test where a bit of the patient's blood is introduced to a bit of the donor's blood to see how they get along. Ideally, the blood samples will hit it off like old friends. If they mix well and settle in for a card game and a beer, all is well. On the other hand, if they start throwing punches, It's time to go back to the drawing board (or at least to the blood bank). If incompatible blood is transfused from one person to another, the reactions can be anything from anaphylactic shock to bleeding disorders. Just to muddy the bloody waters a bit more, a positive test is not a good thing, but a negative test is.

In typical medical fashion, the terminology of a positive or negative test is not referring to the preferred outcome, but to the presence or absence of a reaction. So, a positive test means that the blood did, indeed, have a reaction. Usually that reaction is for the recipient's blood to attack and kill the donor's blood. A raging battle in one's bloodstream significantly distracts from the blood's ability to actually perform its work. A negative test, however, means that the two blood samples are truly keen on each other and will work together like old partners. Continue Reading The Blood Typing Game - Tutorial 1: What is a blood type? Tutorial 1 What is a blood type? Before Nobel Prize awarded Karl Landsteiner discovered the ABO human blood groups in 1901, it was thought that all blood was the same. This misunderstanding led to fatal blood transfusions. Later, in 1940, Landsteiner was part of discovering another blood group, the Rh blood group system. There are many blood group systems known today, but the ABO and the Rh blood groups are the most important ones used for blood transfusions.

The designation Rh is derived from the Rhesus monkey in which the existence of the Rh blood group was discovered. What is blood made up of? An adult human has about 4–6 liters of blood circulating in the body. Among other things, blood transports oxygen to various parts of the body. Blood consists of several types of cells floating around in a fluid called plasma. Image source: National Cancer Institute, USA. Photo: Bruce Wetzel and Harry Schaefer This is a scanning electron microscope image of human blood. The red blood cells contain hemoglobin, a protein that binds oxygen. Red blood cells transport oxygen to, and remove carbon dioxide from, the body tissues. The white blood cells fight infection. One type of infection-fighting white blood cells fight disease by producing antibodies and thus destroying foreign materia. The platelets help the blood to clot, if you get a wound for example. The plasma contains salts and various kinds of proteins. How do the blood types differ? Our blood types are determined by heredity. People belong to either of eight different blood types: A Rh+, A Rh-, B Rh+, B Rh-, AB RH+, AB Rh-, 0 Rh+, or 0 Rh- .

The eight blood types have different combinations of certain molecules, antigens, on the surface of the red blood cells. The A and B antigens are sugars and the Rh antigens are proteins. The antigens expressed in the red blood cells determine an individual's blood type. Also the combination of some other molecules floating around in the blood plasma differs between the eight blood types, the so called antibodies. You can have A or/and B or/and Rh antigens or none of them. You can have A or/and B or/and Rh antibodies or none of them. All eight blood types Antigens (on the surface of the red blood cells): A indicates there are A antigens. (Rh- indicates there are no Rh antigens) Antibodies (in the blood plasma): B antibodies. Rh antibodies. (If there are A antigens but no B nor Rh antigens, the antibodies in the blood plasma are B and Rh antibodies.) The blood type notation A Rh- indicates which antigens and antibodies are present in the blood. Blood type A Rh+ Antigens (on the surface of the red blood cells): A indicates there are A antigens. Rh+ indicates there are Rh antigens.

Antibodies (in the blood plasma): B antibodies. If there are A and Rh antigens but no B antigens, the antibodies in the blood plasma are B antibodies. The blood type notation A Rh+ indicates which antigens and antibodies are present in the blood. Blood type B Rh- Antigens (on the surface of the red blood cells): B indicates there are B antigens. (Rh- indicates there are no Rh antigens.) Antibodies (in the blood plasma): A antibodies. Rh antibodies. (If there are B antigens but no A nor Rh antigens, the antibodies in the blood plasma are A and Rh antibodies.) The blood type notation B Rh- indicates which antigens and antibodies are present in the blood. Blood type B Rh+ Antigens (on the surface of the red blood cells): B indicates there are B antigens. Rh+ indicates there are Rh antigens. Antibodies (in the blood plasma): A antibodies. If there are B and Rh antigens but no A antigens, the antibodies in the blood plasma are A antibodies. The blood type notation B Rh+ indicates which antigens and antibodies are present in the blood.

Blood type AB Rh- Antigens (on the surface of the red blood cells): AB indicates there are both A and B antigens. (Rh- indicates there are no Rh antigens.) Antibodies (in the blood plasma): Rh antibodies. (If there are A and B antigens but no Rh antigens, the antibodies in the blood plasma are Rh antibodies.) The blood type notation AB Rh- indicates which antigens and antibodies are present in the blood. Blood type AB Rh+ Antigens (on the surface of the red blood cells): AB indicates there are both A and B antigens. Rh+ indicates there are Rh antigens. Antibodies (in the blood plasma): No antibodies! (If all possible antigens are present, A, B and Rh antigens, there are no antibodies in the blood plasma.) The blood type notation AB Rh+ indicates which antigens and antibodies are present in the blood. Blood type O Rh- Type O blood gets its name because it has neither A nor B antigens! In other languages O is often pronounced as "null". Antigens (on the surface of the red blood cells): No antigens!

(O indicates there are neither A nor B antigens.) (Rh- indicates there are no Rh antigens.) Antibodies (in the blood plasma): A antibodies. B antibodies. Rh antibodies. (If there are no antigens at all on the surface of the red blood cells, all three possible antibodies are present in the blood plasma: A, B and Rh antibodies.) The blood type notation O Rh- indicates which antigens and antibodies are present in the blood. Blood type O Rh+ Type O blood gets its name because it has neither A nor B antigens! In other languages O is often pronounced as "null". Antigens (on the surface of the red blood cells): (0 indicates there are neither A nor B antigens.) Rh+ indicates there are Rh antigens. Antibodies (in the blood plasma): A antibodies. B antibodies (If there are Rh antigens but no A nor B antigens, the antibodies present in the blood plasma are A and B antibodies.) The blood type notation O Rh+ indicates which antigens and antibodies are present in the blood.

Disclaimer: The fact that people with Rh- blood do not naturally have Rh antibodies in the blood plasma (as one can have A or B antibodies, for instance) is not taken into consideration in this game. In reality a person with Rh- blood can develop Rh antibodies in the blood plasma if he or she receives blood from a person with Rh+ blood. The received blood cells with Rh antigens can trigger the production of Rh antibodies in an individual with Rh- blood. In the game one has to pretend that all patients with Rh- blood type has received Rh+ blood in previous blood transfusions. Also, the antibodies are here referred to as A antibodies, B antibodies and Rh antibodies. These are also commonly referred to as anti A antibodies, anti B antibodies, and anti Rh antibodies. Blood Typing: The Test Blood Typing Also known as: Blood Group; Rh Factor Formal name: ABO Group and Rh Type Is there anything else I should know? How is it used? Blood typing is used to determine an individual's blood group, to establish whether a person is blood group A, B, AB, or O and whether he or she is Rh positive or Rh negative.

Blood typing may be used to: Ensure compatibility between the blood type of a person who requires a transfusion of blood or blood components and the ABO and Rh type of the unit of blood that will be transfused. Blood typing is often done in conjunction with other tests such as an RBC antibody screen and a crossmatch to determine what type of blood or blood components the person can safely receive. A potentially fatal transfusion reaction can occur if a unit of blood containing an ABO antigen to which the blood recipient has an antibody is transfused to the recipient. For example, people with blood group O have both anti-A and anti-B antibodies in their blood. If a unit of blood that is group A, B, or AB is transfused to this person, the antibodies in the recipient's blood will react with the red blood cells, destroying them and causing potentially serious complications. Similarly, if an Rh-negative individual is transfused with Rh-positive blood, it is likely that the person will produce antibodies against Rh-positive blood. Although this situation does not cause problems for the recipient during the current transfusion, a future transfusion with Rh-positive blood could result in a serious transfusion reaction. Determine compatibility between a pregnant woman and her developing baby (fetus).

Rh typing is especially important during pregnancy because a mother and her fetus could be incompatible. If the mother is Rh negative but the father is Rh positive, the fetus may be positive for the Rh antigen. As a result, the mother's body could develop antibodies against the Rh antigen. The antibodies may cross the placenta and cause destruction of the baby's red blood cells, resulting in a condition known as hemolytic disease of the fetus and newborn (HDFN) . To prevent development of Rh antibodies, an Rh-negative mother is treated with an injection of Rh immune globulin during her pregnancy and again after delivery if the baby is Rh-positive. The Rh immune globulin binds to and "masks" the fetus's Rh antigen during pregnancy and delivery and prevents the mother from developing antibodies against the Rh antigen. Determine the blood group of potential blood donors at a collection facility. Units of blood collected from donors are blood typed and then appropriately labeled so they can be used for people that require a specific ABO group and Rh type. Determine the blood group of potential donors and recipients of organs, tissues, or bone marrow , as part of a workup for a transplant procedure.

Along with HLA testing , ABO blood typing is used to identify and match organ and tissue transplant donors with recipients who have the same or an acceptable number of matching HLA genes and antigens. ^ Back to top When is it ordered? ABO grouping and Rh typing are performed on all donated blood. They are also performed when people require blood transfusion. Conditions or situations that may warrant a transfusion include: Secretors and Non-secretors An overview and preview of the new saliva-based secretor test Introduction In the book Eat Right 4 Your Type, Dr. D'Adamo introduced readers to the concept of Secretors/Non-secretors. By now you are familiar with the concept that your ABO blood type is controlled by your genetics. The gene coding for your blood type lies on chromosome 9q34. However, a separate gene actually interacts with your blood type gene, determining your ability to secrete your blood type antigens into body fluids and secretions. In the genetics of the secretor system two options exist. A person can be either a Secretor (Se) or a Non-secretor (se). This is completely independent of whether you are a blood type A, B, AB, or O.

This means that someone can be an A Secretor or an A Non-secretor, a B Secretor, or a B Non-secretor etc. In a simplified sense, a Secretor is defined as a person who secretes their blood type antigens into body fluids and secretions like the saliva in your mouth, the mucus in your digestive tract and respiratory cavities, etc. Basically what this means is that a secretor puts their blood type into these body fluids. A Non-secretor on the other hand puts little to none of their blood type into these same fluids. As a general rule, in the U.S. about 20% of the population are Non-secretors (with the remaining 80% being Secretors). The Secretor Edge With respect to the ABO blood types, it is very difficult to state that one type is more advantageous than another. Each blood type has its own strengths and characteristic weaknesses. However, this does not appear to be the case with the Secretor gene. As a generality, being a Non-secretor (based on all of the available information) does actually appear to be a potential health disadvantage.

At a very basic level, being able to secrete blood type into your saliva, mucus, etc. allows for an added degree of protection against the environment, particularly with respect to microorganisms and lectins. An additional advantage of being a Secretor might be a generalized tendency to promote a stabilized, blood-type friendly intestinal bacterial ecosystem. Many of the friendly (probiotic) bacteria in your digestive system actually use your blood type as one of their preferential foods. Since Secretors have a steady supply of blood type in the mucus that lines the digestive tract, their bacteria have a much more constant food supply. Metabolic Differences Between Secretors and Non-Secretors Similar to the ABO blood types, it appears additional genetic information must be linked to the Secretor gene, because predictable trends in non-blood type aspects of physiology have a close association with Secretor/Non-secretor status. Aspects of physiology such as the relative activity of an enzyme called intestinal alkaline phosphatase; propensities toward clotting, reliability of some tumor markers, and generalized performance of your immune system have predictable trends depending upon your Secretor status. The activity of intestinal and serum alkaline phosphatase is strongly correlated with secretor phenotypes.

Basically, Non-secretors, independent of their ABO blood groups, have lower alkaline phosphatase activity (as you might remember type O's have the highest alkaline phosphatase activity and type A's the least). It has been estimated that the serum alkaline phosphatase activity of Non-secretors is only about 20% of the active in the secretor groups. As was mentioned in Eat Right 4 Your Type, blood type impacts the clotting ability to a significant degree. In fact, it has been estimated that a significant fraction (30%) of the genetically determined variance in plasma concentration of the von Willebrand factor antigen (vWf) is directly related to ABO blood type. As a rule, it is blood group O individuals who have the lowest amount of this clotting factor and the tendency for the lowest degree of clotting/platelet aggregation. In the Secretor/Non-secretor world, Secretors have the slowest clotting while Non-secretors have shorter bleeding times and a tendency towards higher factor VIII and vWf. ABO and Secretor genetics actually further interact to influence blood viscosity.

In essence what this means is that an A Non-secretor will be at the far end of the spectrum with the slowest bleeding times, thickest blood viscosity, and the most probability to have high platelet aggregation. On the other end on the continuum will be O Secretors, who will have the longest bleeding time, thinnest blood, and least tendency for platelet aggregation. Because of this, Non-secretors (especially the type A's) tend to be at the highest risk for future atherothromboti and heart disease. Disease Susceptibility among Secretors and Non-secretors: Digestive System As a general rule, a higher intensity of oral disease is found among Non-secretors. This includes dysplasia (precancerous changes to the tissue) and an increase in cavities. Statistically speaking, blood type A Secretors have the lowest number of cavities. Non-secretors also tend to have more digestive problems. Several studies have indicated that Non-secretors have a significantly higher rate of duodenal and peptic ulcers. Non-secretors are also less resistant to infection by Helicobacter pylori (a microbe associated with ulcers).

It appears that this organism can colonize more readily and generate more inflammation in individual's incapable of secreting their blood type into the digestive tract. Non-secretors are at an increased risk for development of celiac disease (up to 48% of patients with celiac disease have been reported to be Non-secretors). Respiratory System With regards to aspects of lung function, being a Non-secretor takes its usual place as a health disadvantage. Several researchers have suggested that being a Non-secretor might predispose an individual to damaging effects, while being a secretor might add a degree of protection against harmful environmental assaults to our lungs. Among coal miners, asthma was significantly related to Non-secretor phenotype. Secretors also appear to receive a degree of protection against some of the deleterious effects of cigarette smoking. Evidence suggests that the ability to secrete ABO blood type antigens might decrease the risk of Chronic Obstructive Pulmonary Disease (COPD). Being a Non-secretor also offers a slight increase risk for having a problem with habitual snoring.

Autoimmune Disease Non-secretors appear to have an increase in the prevalence of a variety of autoimmune diseases including ankylosing spondylitis, reactive arthritis, psoriatic arthropathy, Sjogren's syndrome, multiple sclerosis, and Grave's disease. Diabetes, Heart Disease, & Metabolic Syndrome X Non-secretors are at a greater risk of developing diabetes (especially adult onset diabetes); and they might be at a greater risk of developing complications from diabetes. Data allows the conclusion that Non-secretors are a risk factor for myocardial infarction and heart disease (note: this is particularly true for men). Several different researchers have noted a connection between a metabolic syndrome called "Syndrome X" and Non-secretor blood types. Syndrome X is a clustering of metabolic problems comprised of insulin resistance (your cells do not respond effectively to the insulin that you create), elevated plasma glucose (high blood sugar), lipid regulation problems (elevated triglycerides, increased small low-density lipoproteins, and decreased high-density lipoproteins), high blood pressure, a prothrombic state (tendency to clotting), and obesity (especially central obesity or a predisposition to gaining weight in the abdomen).

This cluster of metabolic disorders seem to interact to promote the development of diabetes (adult onset type II), atherosclerosis, and cardiovascular disease. And while insulin resistance might lie at the heart of the problem, all of these metabolic disorders appear to contribute to health problems. Alcoholism Alcoholism has been associated with the Non-secretor blood type. On the positive side, alcohol consumption appears to exert a protective effect on lung function and to lower the risk of heart disease more in Non-secretors than in Secretors. The key principle with the use of alcohol is for Non-secretors (and everybody actually) is moderation. Bacteria Urinary Tract Infections Non-secretors are at a greater risk for recurrent UTI's, have a greater tendency to increased inflammation, and are much more likely to develop renal scars. Being a blood type Secretor on the other hand offers a degree of protection; cutting your risk of recurrent UTI's by greater than 50% and dramatically decreasing the likelihood you will have renal scars develop.

Candida infection Based upon this tendency of Non-secretor saliva to not only fail to prevent attachment of Candida, but maybe actually promote the binding of Candida to your tissue, we would expect that research would show higher tendency to Candida problems among Non-secretors. This is what we find to be true. Non-secretors are much more likely to be carriers of Candida and to have problems with persistent infections. Blood type O Non-secretors might be the most affected of the Non-secretor blood types, since Candida also appears to have an easier time colonizing (attaching to) the blood type O antigen. Antibody levels Secretors are known to have higher levels of IgG and IgA antibodies. The lack of IgA antibodies perhaps explains the link between non-secretor status and an increased frequency of heart valve problems secondary to bacteria infection. Because IgA functions much like the way a rampart or palisade wall protects a town from invasion, most if not all non-secretors have problems with gut permiability ("leakygut").

Blood Grouping Experiment (Theory) : Immunology Virtual Lab I : Biotechnology and Biomedical Engineering : Amrita Vishwa Vidyapeetham Virtual Lab To understand the basic concept of Blood Grouping. Principle: It was in 1901, that Austrian-American immunologist and pathologist Karl Landsteiner discovered human blood groups. Karl Landsteiner's work helps to determine blood groups and thus opened a way for blood transfusions which can be carried out safely. He was awarded the Nobel Prize in Physiology or Medicine in 1930 for this discovery. Death of the patient was the result in most cases before 1900, when blood transfusion was attempted. Blood transfusion was made much safer by the discovery of blood groups, as blood of the same ABO group could be chosen for each patient. However, there were still many cases of unexplained blood transfusion reactions. Biologists still went in search of these unexplained questions. In 1902, the fourth main type, AB was found by Decastrello and Sturli.

It was the observations of Levine and Stetson in 1939, and Landsteiner and Weiner in 1940, that laid the foundations of our knowledge about the remaining major blood group- the Rhesus system. Once reliable tests for Rhesus grouping had been established, transfusion reactions became rare! For this discovery Landsteiner was awarded the Nobel Prize in Physiology or Medicine in 1930. The Components of Blood The circulatory system distributes about 4-6 liters of blood to the adult human body. The blood mainly has 2 portions: the Plasma and the Blood Cells. Plasma is mainly composed of water, but contains different types of proteins and other chemicals such as: enzymes, glucose, fat particles, salts ,hormones , antibodies etc. It constitutes about 60% of the blood. Blood cells can be observed under a microscope on staining. The formation of blood cells occur in the bone marrow by the 'Hematopoietic stem cells'. They can be divided into 3 basic cell types: Erythrocytes- Red Blood Cells (RBC): As the name suggests, these red coloured cells give blood its red colour.

(The word erythrocyte is from erythro-Gk.meaning red and Latin-cytos meaning cell.) 1 ml of blood contains approximately 5 million RBCs! The proportion of blood occupied by red blood cells is referred to as the hematocrit, and is normally about 45%. Mature RBCs are biconcave in shape, lack a Nucleus and many other organelles. They circulate in the system for about 120 days, carrying out their job, i.e., to supply oxygen. This function is carried out by them most efficiently. since they are rich in an Iron-containing biomolecule called haemoglobin. Haemoglobin has high affinity for oxygen, thus binds to it and is transported from the alveoli (in lungs) to every part of the body. There is constant replenishment of RBCs in order to remove old cells that break down. (This process is carried out in organs like the liver, also producing by-products like bile pigments.) Millions of cels are released into the bloodstream from the bone marrow each day. Leukocytes- White Blood Cells: These cells are key players in our immune system.

They are of different types such as neutrophils, lymphocytes, eosinophils, monocytes, basophils. Each of them have a variety of functions in our immunity. 1 ml of blood of an adult human contains about 4,000-11,000 leukocytes. Basically, they destroy and remove old or aberrant cells and clear cellular debris, as well as attack foreign substances and infectious agents (pathogenic entities). Thrombocytes- Platelets: The coagulation or blood clotting process is taken care of by them. They act on clotting proteins like Fibrinogen, converting it into Fibrin. They create a mesh onto which RBCs collect and form a clot. This prevents excessive blood loss and also checks the entry of pathogens into the body. 1 ml of blood of an adult human contains about 200,000-500,000 platelets. The observations that led to the discovery of blood groups: At times, it was observed that mixing blood from two individuals led to blood clumping or agglutination.

Later it was understood that the agglutinated red cells can clog blood vessels and stop the circulation of the blood to various parts of the body. The agglutinated red blood cells also crack and their contents leak out in the body. The RBCs contain haemoglobin which becomes toxic when outside the cell. This must have been the phenomena that occurred in the blood transfusion cases that ended up with fatality of the patient at the receiving end. Karl Landsteiner discovered that blood clumping was an immunological reaction which occurs when the receiver of a blood transfusion has antibodies against the donor blood cells! People learned that, compatibility of blood groups needed to be checked before anything else was done. If they are not, the red blood cells from the donated blood will agglutinate. This can have fatal consequences for the patient. ABO blood grouping system: According to the AB0 blood group system there are four different kinds of blood groups: A, B, AB and O (null). Rh factor Rh (Rhesus) factor is found on the RBC's surface in most people. Like A and B, this is also an antigen and those who have it are called Rh+.

Those who lack the antigen on the surface of RBCs are called Rh-. A person with Rh- blood does not have Rh antibodies naturally in the blood plasma. But a person with Rh- blood can develop Rh antibodies in the blood plasma if he or she receives blood from a person with Rh+ blood, whose Rh antigens can trigger the production of Rh antibodies (as the immune system is triggered by the presence of an unknown antigen in the system). A person with Rh+ blood can receive blood from a person with Rh- blood without any problems. Blood groups for each individual are determined by genes or alleles (small packets of information in cells contained in the DNA) which are inherited from both parents. Genes for the Rh-ve and O groups from one parent are masked (i.e., they are recessive) by the presence of Rh+ve and A or B genes from the other parent. That is, O and Rh negative genes only produce an effect when there is a "double dose" of such genes, i.e., one from each parent (homozygous condition). Thus, people who are apparently A or B Rh+ve may also carry genes for the O and Rh-ve blood groups which can be inherited by their children.

Principle behind blood tests: Blood clumping or Agglutination observation. Compatibility between the blood groups of donor and recipient determines the success of a blood transfusion. The AB0 and Rh blood groups are looked at while conducting the test. In a diagnostic lab, Monoclonal antibodies are available for A, B and Rh antigen. Monoclonal antibody against Antigen A (also called Anti-A), comes in a small bottles with droppers; the monoclonal suspension being BLUE in colour. Anti-B comes in YELLOW colour. Anti-D (monoclonal antibody against Rh) is colourless. All the colour codes are universal standards. When the monoclonal antibodies are added one by one to wells that contain the test sample (blood from patient), if the RBCs in that particular sample carry the corresponding Antigen, clumps can be observed in the corresponding wells. A drop of blood is left without adding any of the antibodies; it is used as a control in the experiment. The monoclonal antibody bottles should be stored in a refrigerator. It is recommended to tilt the bottle a couple of times before use in order to resuspend the antibodies that have settled at the bottom of the bottle.

Rh Disease - Health Encyclopedia - University of Rochester Medical Center Rh Disease What is Rh disease? Rh disease occurs during pregnancy. It happens when the Rh factors in the mom’s and baby’s blood don’t match. It may also happen if the mom and baby have different blood types. What causes Rh disease? Each person has a blood type (O, A, B, or AB). Everyone also has an Rh factor (positive or negative). The Rh factor is a protein on the covering of the red blood cells. If the Rh factor protein is on the cells, the person is Rh positive. If there’s no Rh factor protein, the person is Rh negative. A baby may have the blood type and Rh factor of either parent, or a combination of both parents. There can be a problem when an Rh negative mother has a baby with an Rh positive father. If the baby's Rh factor is positive, like his or her father's, this can be an issue if the baby's red blood cells cross to the Rh negative mother. When this happens, the mom becomes sensitized to Rh positive blood. This often happens at birth when the placenta breaks away. But it may also happen any time the mom’s and baby's blood cells mix.

This can occur during a miscarriage or fall. It may also happen during a prenatal test. These can include amniocentesis or chorionic villus sampling. These tests use a needle to take a sample of tissue. They may cause bleeding. The Rh negative mom’s immune system sees the baby's Rh positive red blood cells as foreign. Your immune system responds by making antibodies to fight and destroy these foreign cells. Your immune system stores these antibodies in case these foreign cells come back again. This can happen in a future pregnancy. You are now Rh sensitized. Rh sensitization normally isn’t a problem with a first pregnancy. Most issues occur in future pregnancies with another Rh positive baby. During that pregnancy, your antibodies cross the placenta to fight the Rh positive cells in your baby's body. As the antibodies destroy the cells, your baby gets sick. Your baby could have jaundice, heart failure, and enlarged organs. Who is at risk for Rh disease? Women who are Rh negative and are pregnant with a baby whose father is Rh positive are at risk for this condition. Your risk is much higher if you’ve been pregnant before. There is normally no risk for Rh disease during a first pregnancy, unless you’ve been sensitized before pregnancy.

What are the symptoms of Rh disease? A mother has no signs of Rh disease. But your baby can have problems if you develop antibodies. Symptoms can occur a bit differently in each pregnancy and child. During pregnancy, symptoms may include: A yellow coloring of amniotic fluid. This color may be because of bilirubin. This is a substance that forms as blood cells break down. Your baby may have a big liver, spleen, or heart. There may also be extra fluid in his or her stomach, lungs, or scalp. These are signs of hydrops fetalis. This condition causes severe swelling (edema). Rh disease can cause problems in your newborn. The condition caused by Rh disease in babies is called hemolytic disease of the newborn (HDN). Your baby may have the following symptoms: Yellow coloring of the skin and whites of the eyes (jaundice) Pale-coloring because of anemia Swelling under the skin Large abdomen The symptoms of Rh disease may look like symptoms of other conditions. See your healthcare provider for a diagnosis. How is Rh disease diagnosed? Your healthcare provider may suspect Rh disease if you had an Rh positive baby in a past pregnancy. Your healthcare provider will ask you about your health history.

He or she will also give you an exam. You may need the following tests to check for Rh disease: Testing for Rh positive antibodies in your blood. Ultrasound. This test can show enlarged organs or fluid buildup in your baby. Amniocentesis. This test checks the amount of bilirubin in the amniotic fluid. In this test, a needle is inserted into your abdominal and uterine wall. It goes through to the amniotic sac. The needle takes a sample of amniotic fluid. Percutaneous umbilical cord blood sampling or fetal blood sampling. In this test, a blood sample is taken from your baby’s umbilical cord. Your child’s healthcare provider will check this blood for antibodies, bilirubin, and anemia. How is Rh disease treated? Treatment will depend on your pregnancy and general health. It will also depend on how severe the condition is. Intrauterine blood transfusion This test puts red blood cells into your baby's circulation. In this test, a needle is placed through your uterus. It goes into your baby’s abdominal cavity to a vein in the umbilical cord. Your baby may need sedative medicine to keep him or her from moving.

You may need to have more than one transfusion. Early delivery If your baby gets certain complications, he or she may need to be born early. Your healthcare provider may induce labor once your baby has mature lungs. What are the complications of RH disease? Complications from Rh disease in your baby may include: Anemia. In some cases, anemia is severe. Your baby’s spleen and liver may be enlarged. Jaundice Hydrops fetalis. This happens when your baby's organs aren’t able to handle the anemia. Your baby’s heart will start to fail. This will cause large amounts of fluid buildup in your baby's tissues and organs. Babies with this condition are at risk for being stillborn. After birth, your baby may have the following: Severe jaundice. Your baby’s liver can’t handle the large amount of bilirubin. This causes your baby’s liver to grow too big. He or she will still have anemia. Kernicterus. The most severe form of too much bilirubin. It’s due to the buildup of bilirubin in your baby’s brain. This can cause seizures, brain damage, and deafness. It can even cause death.

Can Rh disease be prevented? Rh disease can be prevented. Almost all women will have a blood test to learn their blood type early in pregnancy. If you’re Rh negative and have not been sensitized, you’ll get a medicine called Rh immunoglobulin (RhoGAM). This medicine can stop your antibodies from reacting to your baby’s Rh positive cells. You’ll get RhoGAM around week 28 of pregnancy. You may get it earlier if you have vaginal bleeding, trauma, or amniocentesis before 28 weeks. If your baby is Rh positive, you’ll get a second dose of medicine within 72 hours of giving birth. If your baby is Rh negative, you won’t need a second dose. When should I call my healthcare provider? Call your healthcare provider if you’re Rh negative and have vaginal bleeding or trauma during your pregnancy. Your healthcare provider may give you RhoGAM. Key points about Rh disease Rh disease occurs during pregnancy. It happens when the Rh factors in the mom’s and baby’s blood don’t match. If the Rh negative mother has been sensitized to Rh positive blood, her immune system will make antibodies to attack her baby.

When the antibodies enter your baby's bloodstream, they will attack the red blood cells. This causes them to break down. This can lead to problems. This condition can be prevented. Women who are Rh negative and haven’t been sensitized can receive medicine. This medicine can stop your antibodies from reacting to your baby’s Rh positive cells. Next steps Blood Types (Blood Group) | myVMC Blood Types (Blood Group) Implications of Rhesus blood groups during pregnancy Introduction to blood types All cells, including those that make up blood, have a combination of substances known as antigens on their surfaces that is inherited. Antigens function to enable our immune system to distinguish the body’s own cells from foreign invaders. When invaders are recognised, they are destroyed by antibodies, which are also produced by the immune system. In blood typing, antigens on the surfaces of red blood cells (RBCs) are also known as agglutinogens and the antibodies that react against them are also called agglutinins. Antibodies in the blood are found in the plasma. Information on re-publishing of our images The ABO blood group The ABO blood groups are made up of 4 types of blood – A, B, AB and O.

An individual’s ABO blood type is determined by the hereditary presence or absence of the antigens A and B on the surfaces of RBCs. Antibodies of the ABO group appear in the plasma 2-8 months after birth mainly in response to the bacteria that inhabit the intestines. However, antibodies cross-react with RBC antigens that are different to those present on the individual’s own RBCs. This cross-reaction can be fatal and therefore has great significance in blood transfusions. Identifying ABO blood types People with type A blood have the antigen A on the surface of their RBCs, while people with type B blood have the B antigen. Individuals with type AB blood have both A and B antigens, whereas people with type O blood have no antigens present (there is no antigen O). The antibody that reacts against antigen A is called anti-A, and is found in the plasma of people who do not possess antigen A on their own RBCs – that is, people with type O or type B blood. The antibody that reacts against antigen B is called anti-B and is present in those who do not possess antigen B in their RBCs – people with type O or type A blood.

Importance of ABO blood groups in transfusions An antibody can attach to several RBCs at once and bind them together. Agglutination is the clumping of RBCs bound together by antibodies. In giving transfusions, it is very important that the donor’s RBCs not agglutinate as they enter the recipient’s bloodstream. For example, if type B blood (with B antigens) were transfused into a type A recipient (with anti-B antibodies), the recipient’s anti-B antibodies would immediately agglutinate the donor’s RBCs, causing a transfusion reaction where the agglutinated RBCs block small vessels and release their haemoglobin (Hb) over the next few hours to days. This free Hb can block the kidney tubules and cause death from kidney failure within a day or so. Therefore, a person with type A (anti-B) blood cannot receive B or AB blood, a person with type B (anti-A) blood cannot receive A or AB blood, and a person with type O (anti-A and ant-B) blood cannot receive A, B or AB blood.

Type AB blood is sometimes called the universal recipient because it lacks both anti-A and anti-B antibodies, so it will not agglutinate donor RBCs of any ABO type. Type O may sometimes be called the universal donor, because since there is no “anti-O” antibody, recipients of any ABO type may receive type O blood. Type O None The Rhesus blood group The Rhesus or Rh blood group is named after the rhesus monkeys in which they were first discovered. Individuals either belong to the Rh-positive (Rh+) or Rh-negative (Rh-) Rhesus blood group. People with the Rh+ blood group have D antigens on the surface of their red blood cells, while Rh- individuals do not. In contrast to the ABO group, anti-D antibodies that react against D antigens are not usually present in the blood under normal conditions. They only form in Rh- individuals who are exposed to Rh+ blood. If an Rh- receives an Rh+ transfusion, the recipient produces anti-D antibodies. Since anti-D does not form instantaneously, there is little danger in the first mismatched transfusion.

However, because the recipient will now start producing anti-D, a subsequent Rh+ transfusion could agglutinate the donor’s RBCs. Implications of Rhesus blood groups during pregnancy A related condition can occur when a Rh- woman is pregnant with a Rh+ foetus. The first pregnancy is generally uneventful since anti-D does not form right away, so that even if the mother is exposed to Rh+ foetal blood via miscarriage or placental tearing at the time of birth, there is no danger to her first Rh+ child. However, she does begin to produce anti-D antibodies upon her first exposure to Rh+ foetal blood, although this does not occur instantaneously. If she becomes pregnant again with a Rh+ foetus, her anti-D antibodies can pass through the placenta and agglutinate the foetal RBCs. Agglutinated RBCs haemolyse (release their Hb), and the baby is born with a severe anaemia called haemolytic disease of the newborn (HDN) , which may kill the infant or leave brain damaged. HDN is relatively easy to prevent, while very difficult to treat.

A Rh- mother is at risk of having a Rh+ baby if the baby’s father is Rh+. As a result, it is now common to give immune globulin at 28-32weeks gestation and at birth to any pregnancy involving a Rh- mother and a Rh+ father. Immune globulin binds foetal RBC antigens so that they cannot stimulate the mother’s immune system to produce anti-D, hence preventing HDN. References Saladin KS. Anatomy and physiology – the unity of form and function. 3rd ed. New York: McGraw-Hill; 2004. Sherwood L. Human physiology – from cells to systems. 5th ed. Belmont, Calif: Brooks/Cole; 2004.

Question: What fluid has groups called A, B, AB and O?
Answer: Blood