Abo-rh Blood Typing

Immunology and Virology

PRACTICAL ABO-Rh Blood Typing Objectives 1. Perform standard test used for blood type identification 2. Understand the importance of blood type identification and its uses 3. Understand the concept of haemagglutination Materials 1. Blood Test Card 2. Blood 3. Anti-Rh (D) serum 4. Anti-A serum 5. Anti-B serum 6. Mixing sticks (blue, yellow, white) Methodology 1. A Blood Test Card (or a glass slide) is obtained. A drop of Anti-A serum (blue) is placed in the circle labeled “Anti-A”. The cap is replaced on the Anti-A vial. The cap is always replaced on one vial before opening the next vial to prevent cross contamination. 2. A drop of Anti-B serum (yellow) is placed I the circle labeled “ Anti-B” and then the cap is replaced. 3. If the Rh typing is being done (if not, proceed to step 4), a drop of Anti-D serum (clear) is placed in the circle labeled “Anti-D”. The cap is replaced on the Anti-D vial. 4. The tip of middle finger is scrubbed with an alcohol-soaked swab (or if blood cells are supplied, a drop of blood cells are put in each “Blood” circle and proceeded to step 8. 5. A disposable sterile lancet, is removed from its wrapper. The middle finger is firmly pressed about 1 cm from the fingertip with the thumb of the same hand and the clean fingertip is punctured with the lancet. The lancet is discarded. A lancet should never be reused; someone else’s lancet should never be reused, 6. The finger is gently pressed to force out a drop of blood onto each of the circles labeled “Blood” on the Blood Test Card. 7. Any excess blood from the finger is wiped with the alcohol swab. In most cases, bleeding will stop 1 to 2 minutes. Should bleeding continue, the finger is covered with an adhesive bandage. 8. If Rh typing are being done (if not, proceeded to step 8), the white stirring stick is used to mix one drop of blood with the Anti-D serum. The blood and the serum mixture are carefully spread with the stirring stick until the mixture covers both connecting circles. The stirring stick is then discarded.

Immunology and Virology

9. The blue stirring stick is used to mix one drop of blood with the Anti-A serum. The blood and the serum mixture is carefully spread with the stirring stick until both connecting circles are covered by the mixture. Then the stirring stick is discarded. 10. The yellow stirring stick is used to mix one drop of blood with the Anti-B serum. The blood and the serum mixture is carefully spread with the stirring stick until both connecting circles are covered by the mixture. Then the stirring stick is discarded. Note: Careful precautions are taken to ensure no cross contamination occurs as even the slightest mixing will ruin the test results. 11. The test card is gently rocked back and forth for 1 minute. Each mixture is ensured to be in its circle. 12. The Blood Test Card is tilted, allowing he blood and the serum mixtures to drain to the side but not out of the circles. The appearance of thin blood films are compared with the illustration table in the manual. If a film remains uniform in appearance, there is no agglutination. If a film appears granular, agglutination has occurred. (Positive Rh reactions may take longer time than positive A and B reactions. Five minutes may be required to obtain an accurate Rh reading). 13. If the test results are not clear, steps 11 and 12 are repeated. 14. After the test sample is dry, a piece of cellophane tape is used to cover it. 15. The blood type is recorded on the Blood Test Card. Result xxx other groups

Immunology and Virology

Immunology and Virology

Discussion 1. Describe the components of blood. Component of Blood Erythrocytes Leukocytes Thrombocytes

Plasma

Description Red blood cells; biconcave discs without nuclei White blood cells; nucleated phagocytic cells Platelets; small cytoplasmic fragments Fluid portion of blood

Function Transport O2 and CO2 Provide immune responses Responsible for blood clotting Transporting nutrients, gases, and vitamins; regulating electrolyte and fluid balance; maintain a consistent blood pH

2. Explain how does red blood cell (RBC) can form agglutination when mix with the specific antibody against the correspond RBC? Agglutination occurs due to the reaction that is caused through the interaction of the proteins in the red blood cells and the antibodies present in the blood plasma. Example: Antibodies-b, also known as Anti-a sera, will clump red blood cells containing A-antigens, or type A blood. Anti-b sera will clump type B blood. Clumping will occur in both sera with type AB blood and in neither sera with type O blood. 3. Describe about Rhesus factor and complication to the fetus when the mother carry the Rh+ antigen. Rh factor is an antigen, a substance that stimulates the production of antibodies to fight foreign invaders, such as viruses, bacteria and transplanted organs. A given individual either

Immunology and Virology

has the antigen already in their blood (they are Rh positive), or they do not (they are Rh negative). A patient's Rh status effects how he or she handles blood transfusions or organ transplants. Rh-positive women does not having risk to have children with the Rhesus factor disease. As for woman with Rh-; they will not encounter any problem with their first child. The problem may arise after the birth of her first child. When the umbilical cord has been cut, and if the baby has the Rh+, little of the baby's blood will flow back into the mother's body. The mother's body will then become immune towards Rh+. When this happens, the subsequent pregnancy for Rh+ baby will not succeed as the baby may die prematurely in the womb or the mother undergoes miscarriages. But, if a Rh- woman is carrying a Rh- baby, it will not be a problem for the mother and the baby in her womb and also for the woman's subsequent pregnancy. Conclusion Through this experiment, we become familiar with standard test used for blood type identification; understand and appreciate the concept and importance of blood type identification and its uses.