Introduction Flashcards
Who discovered the A, B, O blood groups?
Karl Landsteiner
What does the extracellular surface of the RBC membrane consist of?
Proteins
Glycoproteins
Glycolipids
Blood group antigens are important in what circumstances
(5)
Immune destruction of rbcs in allogeneic transfusions
Foeto-maternal incompatability
Autoimmune Haemolytic Anaemia
Organ transplantation
Genetic, forensic and anthropologic investigations
How many blood products are there
53 different products
What happened in the first human transfusion
The patient died
What were the A, B, O blood groups originally called?
A, B and C
What big advancements were made in transfusion after the discovery of ABO blood grouping
Cross matching began in 1907
Why was there advancements in transfusion in 1914
WWI
Anti-coagulants began to be used
Blood needed to travel large distances without clotting
Sodium citrate was used
What discovery was made in 1940?
The Rh blood group system was discovered (Reses blood group)
What began to happen in the 1960s
(3)
Labs began making other blood products such as plasma
Labs began to pool blood together
Diseases such as Hep A and HIV were found in these and infected patients -> huge controversy
How many blood group systems are there
39
How many of the 39 blood groups are clinically significant
7/8 can cause transfusion reactions
What is an allogeneic transfusion?
Foreign to self transfusion
What happens in autoimmune haemolytic anaemia?
Rbc lysis
How are blood groups used in anthropologic investigations
Study of populations
No B in Aboriginals
A in Vikings
B in Spanish
Describe the genetics of the ABO group
Controlled by a single locus on each chromosome e.g. an A on one and a B on the other = AB blood group
How does the blood group systems differ genetically
ABO -> products of alleles at a single locus
Rh or MNSs are closely linked -> very close to each other
Explain why transfusions will never be perfect
We find a new blood group every year
Its impossible to completely match a donor to a recipient
Up to 400 different antigens
What molecules are responsible for the negative charge on rbcs
GPA and GPB
What are the two ways a person can produce antibodies against rbcs antigens
Transfusion
Pregnancy
What happens to rbcs which have been opsonised -> coated in antibodies i.e. after an imperfect transfusion
They will be removed by the spleen or they will lyse in circulation (complement)
Where are naturally occurring antibodies against rbc antigens found and explain how they occur
(3)
Found in the plasma of blood
You will have antibodies against the ABO type you don’t have e.g. a type A will have anti-B antibodies
These antibodies are induced by commensals with very similar antigens in the gut
What does the IBTS do
Collects blood and makes blood products
Screens blood for different virus and bacterial contamination
Quality assurance of produce
Issues products to hospitals
Recruits, selects and retains donors
Blood grouping
What does a hospital blood bank do?
(4)
Screen patients for antibodies
Crossmatches patient serum and transfusion rbcs
Liaison with clinical and nursing staff
Acceptance of specimens from patients and blood grouping
