3 Transfusion
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- Bu səhifədəki naviqasiya:
- Procedure Part I: Blood Typing
- People with : Have: Type A blood Type A carbohydrate antigen
- Blood transfusions — who can receive blood from whom
- Blood Group Antigens on red blood cells Antibodies in plasma
- Blood Phenotype Blood Genotypes
- Genetics of Blood Types
- Father (Type AB) Mother (Type O)
- Father (Type B) Mother (Type A)
- Blood Sample A B O Rh
- Part II: Genetics of Blood Type
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Name ___________________________________ 
Transfusion Confusion – 60 Informal Points Introduction Jane Doe is in the hospital recovering from a car crash. She needs blood, but the blood bank is extremely low. Members of her family have offered to donate, but none of them know their blood type. Jane’s brother Tom, sister Mary, mother Harriett, and Grandpa Ed (her mom’s father) are local and are all willing to be tested. Jane’s other sister Sue is away at college, but she is going to have her blood tested at school and have the results sent to the hospital. Jane’s father, John and Grandmother Mona (her mom’s mother) have passed away. Their blood types remain unknown. There are four types of human blood – type A, type B, type AB and type O. Only certain blood types are compatible with one another and can be safely transferred from person to person in a transfusion. In this activity, you will learn what controls blood type as well as what determines if your blood will “mix well” with that of another person’s. The body has an innate need to protect itself and if something foreign is introduced, it will attack. Anything that is foreign to the body and gets your immune system fired up is referred to as an antigen. Antibodies are proteins in blood and lymph that seek out and bind to specific antigens. These specialized proteins are one of the primary defenders in your body’s army of immunity. Your body contains tons of antibodies, each designed to target and destroy a specific antigen. Our red blood cells have antigens on their surface that act to identify the type of cell. A person with blood type A has A antigens on his/her red blood cells. What antigens do you think you would find on the red blood cells of a person with B blood? Someone who has the A antigen on his/her blood cells would not have Anti-A antibodies circulating in his/her plasma, the liquid portion of blood. If he/she did, the Anti-A antibodies would find and attack the red blood cells marked with the A antigen. When this happens, the blood agglutinates or clumps. A person with the A antigen does, however, have circulating anti-B antibodies. These antibodies do not attack the red blood cells with the A antigen. But what if you introduced B blood cells into the system? In the lab, you will use the rules of antigen/antibody interactions and the presence of visible clumping to determine blood type. Much of this is a review of last year, but this year we are also adding in the concept of the Rh factor (Rhesus Factor.) Rh-positive is the dominant trait whereas Rh- negative is the recessive trait. When a person is Rh-positive they have additional antigens on their red blood cells. However, the immune response is a little different than for blood type. For example, a person with blood type O naturally has both anti-A and anti-B antibodies in his or her blood, meaning if he or she were ever given A, B, or AB blood it will be rejected and kill the patient. However, a person that is Rh-negative does not naturally have antibodies for the positive antigen, instead the immune system first manufactures them only after having been exposed to the positive antigen. For this reason a person that is Rh-negative may safely, without side effects, be given Rh-positive blood one time. However, this initial exposure will cause the body to begin producing Anti-positive antibodies which will last the remainder of their lives. If the person is given Rh-positive a second time then there will be an attack and ill side effects will occur. These side effects are serious, but rarely deadly, like being given the wrong blood type. For this reason, in an extreme emergency with extenuating circumstances it is permissible to give an Rh-negative patient the positive blood. This is also the reason why an Rh-negative woman pregnant with a Rh-positive baby can carry the first baby to full term without any issue, but a second Rh-positive baby would be miscarried without medical intervention. Luckily, modern medicine has discovered the Rh immune globulin (RhIg) that can be injected into the mother and keep both her and her baby safe even if their blood types are not compatible. In this activity, you will type the simulated blood of your patient as well as the blood of her family members. You will analyze the results and use your knowledge of antigen/antibody interactions to determine who is a potential blood donor for Jane. Accurate blood typing is essential for safe blood transfusions. Using information from your blood typing tests, you will create a family pedigree for blood type and use information on this genetic family tree to determine the blood type of those you could not test. As you complete this task, you will learn about the interactions between antigens and antibodies, and you will review basic principles of genetics and inheritance. Procedure Part I: Blood Typing 1.Follow your teacher’s lead to review blood basics. There are many different ways to classify blood types, but the most common blood type classification system is the ABO (said "A-B-O") system. There are four blood types in the ABO system: Type A, Type B, Type AB, and Type O. These blood types refer to different versions of carbohydrate molecules (complex sugars,) which are present on the surface of red blood cells.
The Type A and Type B carbohydrate molecules are called antigens because they stimulate the body to produce an immune response, including antibodies. This means that if you have A and/or B antigens on your red blood cells then the immune system will NOT generate antibodies towards it and they are okay to be in your body. However, if a person does not have the A and/or B antigens then the immune system would attack this type of blood if it every entered the body because it would see the blood as a foreign substance. Antibodies are special proteins that travel in the blood and help our bodies to destroy viruses or bacteria that may have infected our bodies (see figure below.) 
Normally, we do not make antibodies against any molecules that are part of our own bodies. Thus, antibodies help to defend against invading viruses and bacteria, but normally antibodies do not attack our own body cells. For example, people with Type A blood do not make antibodies against the Type A antigen, which is present on their red blood cells, but they do make antibodies against the Type B antigen. Test your understanding of blood groups by filling in the blanks in the chart.
Blood transfusions — who can receive blood from whom?: If you are given a blood transfusion that does not match your blood type, antibodies present in your blood can react with the antigens present on the donated red blood cells. For example, if a person who has Type A blood is given a Type B blood transfusion, then this person's anti-B antibodies will react with the Type B antigens on the donated red blood cells and cause a harmful reaction. This reaction can cause the donated red blood cells to burst and/or clump together and block blood vessels. This type of transfusion reaction is illustrated in the figure below. 
Transfusion reactions can be fatal. To prevent this from happening, doctors test whether a person's blood is compatible with the donated blood before they give a transfusion. A person can only be given donated blood with red blood cells that do not have any antigen that can react with the antibodies in the person's blood. Test your understanding of blood groups by completing the table below.
Now, let’s get a little more specific and add in Rh factors. Positive is dominant and negative is recessive. Fill in the following chart:
Which blood type would be considered a universal donor (someone who can give blood to anyone)? Type O since it is recessive and has no antigens to be fought by the immune system, making it safe for anyone! Which blood type would be considered a universal acceptor (someone who can take blood from anyone)? Type AB since is it codominant and a person with type AB blood has no antibodies. Without antibodies there are no fighter molecules to reject any blood so a person with AB blood can take anything! What about the Rh factor? What does Rh have to do with donating and receiving? OO-- is the absolute best blood to donate because it is recessive in both blood type as well as Rh factor meaning anyone can safely take this blood as many times as needed without any consequences! Genetics of Blood Types: Your blood type is established before you are born, by specific genes inherited from your parents. You receive one blood type gene from your mother and another from your father. These two genes determine your blood type by causing the presence or absence of the Type A and Type B antigen molecules on the red blood cells. In a heterozygous AO person, which allele is dominant, A or O? Explain your reasoning. A because it produces antigens on the blood cells whereas O does not. Codominance refers to inheritance in which two alleles of a gene each have a different observable effect on the phenotype of a heterozygous individual. Thus, in codominance, neither allele is recessive—both alleles are dominant. Which one of the genotypes shown on the last page results in a phenotype that provides clear evidence of codominance? Give the genotype and draw a picture of a red blood cell for this genotype to illustrate how both alleles influence blood type in this case. AB since both alleles show up in the blood type. Each biological parent gives one of their two ABO alleles to their child. For example, a father who has blood type AB has the genotype AB, so he can give either an A or a B allele to a child of his. If the mother has blood type O, her genotype must be OO, and she can only give an O allele to a child. A Punnett Square is a table showing the genotypes of all possible children a couple can create given their genotypes. Below is a punnett square shows the possible genotypes for the children of these parents. Write in the blood type for each genotype to show the possible blood types for the children of these parents.
Next, suppose that a mother has blood Type A and genotype AO and the father has blood Type B and genotype BO. Draw a Punnett square to show the possible genotypes for their children. What blood phenotype would each genotype result in.
2.Put your knowledge of antigen and antibody interactions to the test as you help Jane Doe find a blood donor. Work with a partner to test the blood of each family member and determine blood type based on agglutination.
*Note: Agglutination means “clumping.” Sometimes this is apparent by particle appearing after mixing or just a general cloudiness. 3.Starting with Jane and working one sample at a time, place two drops of simulated blood in the A and the B wells of a clean blood typing slide. 4.Place two drops of Anti-A serum in the well labeled A. 5.Place two drops of Anti-B serum in the well labeled B. 6.Using a separate mixing stick for each well, mix the simulated blood and antiserum for approximately ten seconds. 7.Carefully examine each well to see if the blood has clumped. If agglutination has occurred, place a “+” in the appropriate box in the table. Remember that you will only see agglutination if a specific antibody meets up with its specific antigen. Record your observations and use the information to determine blood type. 8.Using a fresh tray for each sample, repeat the blood typing steps to determine the blood type of the other family members. 9.Using information from the lab, determine who is able to donate blood to Jane and list in the space below. Note that Sue just called in to let everyone know that she is blood type O. Part II: Genetics of Blood Type 10.Remember that pedigrees are diagrams of family relationships that illustrate how a particular trait is passed from person to person. With your teacher, review the structure of pedigrees using the Pedigree Resource Sheet. 11.In the space below, draw a pedigree that shows the distribution of blood type in the Doe family. Remember that in a pedigree, men are represented by squares and women are represented as circles. 12.Write the name of the individual underneath each square or circle in the pedigree, and write the blood type inside of the shape. 13.Work with your partner to analyze your pedigree and to determine blood type for John and Mona. You did not test their blood, but the pedigree will give you many clues. You may be able to narrow it down to just one blood type or you may find that there is more than one possibility. That is OK – take it as far as you can. Mona would have to be AO and John would have to be BO. 
Conclusion Questions
Type AB since is it codominant and a person with type AB blood has no antibodies. Without antibodies there are no fighter molecules to reject any blood so a person with AB blood can take anything!
Jane is blood type A, meaning she has Anti-B antibodies. Mary has AB blood so if Jane were to take Mary’s blood there would be B-antigen in her body and her Anti-B antibodies would attack and kill the cells, killing Jane.
The antibody is a fighter molecule and would attack the antigen, killing the blood cell and the person.
John must have a genotype of BO and a blood type of B. We know this because his daughter Sue is type O so she must have gotten an O allele from each of her parents. Johns daughter Mary is Type AB and had to have gotten the A from mom which means dad must have a B to have given her. 14.Explain why blood is classified as a type of connective tissue. Blood connects the body systems together bringing the needed oxygen, nutrients, hormones and other signaling molecules, and removing the wastes. 15.Explain how blood type contributes to your identity. Each person is one of four blood types, A, B, AB or O. Blood type can never change so it is part of a person’s identity. Yüklə 61,07 Kb. Dostları ilə paylaş:
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