BL- Immunohemotology ABO/Rh Flashcards Preview

BL/DD USMLE and Basics > BL- Immunohemotology ABO/Rh > Flashcards

Flashcards in BL- Immunohemotology ABO/Rh Deck (38):
1

Red cells do not carry MHC antigens in humans, and the antigens they do carry are much less __________ in the population

polymorphic

(that is, many fewer alleles).

2

H substance

Sugar on all red cells

*this is all O has

3

____________catalyse the transfer of activated carbohydrate moieties from donor molecules to an acceptor molecule.

Glycosyltransferases

4

Red cells do not carry:

MHC

5

A-morph

gene that does not code for protein

The O allele is an “amorph;”

6

_________assemble the basic “core” sugar chain which almost everybody has, it is called
the “H” antigen.

Glycosyltransferases

7

Group A blood have a glycosyl transferase allele which puts an additional sugar on the H antigen, and people who are B have a different allelic form of this enzyme which adds a___________

different sugar

8

There are some people who lack the transferase gene that puts the final sugar on the “core”, and thus do not express even the H antigen, so there is no substrate for the A or B glycosyltransferases to modify.

Blood type?

This is the Bombay phenotype (Oh,) and it is rare

9

Can bombay blood groups have blood transfusions?

only from Bombay, cannot accept O

10

Group A and B blood group genotypes can include

O geneotype

ex: you may be AA or AO

11

A blood make anit____

anti b

12

B blood make anit___

anti a

13

O blood make anit___

anti a and anti b

14

AB blood make anit___

Nothing, no anti's

15

Bombay makes anti_____

everything, A B O
Needs xfuision from bombay

16

The second most important blood group system is _______, so called because it was discovered by workers studying rhesus monkeys.

Rh

17

Rhesus (Rh) factor is an inherited trait that refers to a specific protein found on the surface of red blood cells. If your blood has the protein, you're Rh positive — the most common Rh factor. If your blood lacks the protein, you're Rh _____

negative

18

ISOHEMAGGLUTININS

substances that agglutinate the red blood cells of others of the same species, are also found in humans.

Thus, there are four main blood groups, which differ with respect to two antigens, A and B, in the red blood cells and two isohemagglutinins, anti-A and anti-B, in the serum. T

19

Isohemagglutinins are of the______class

IgM

Must be IgM due to placenta crossing

20

Dd

important Rh protin
D= intact
d= amorph

21

DD

Rh +

22

Dd

Rh+

23

dd

Rh -

24

Rh - makes AB against

Rh + blood

25

Red cells live

120 days

26

Do people get blood transfusions for volume?

No

27

If there is no hemolysis or agglutination, the blood and the recipient are considered _______

“compatible”

28

Do we give whole blood?

Generally not, because plasma stuffs can react to recipient cells

We usually give just RBCs

29

is there antibody already on these cells I am
interested in? You rinse off the cells and add antiglobulin to find out.

direct antiglobulin test (DAT)

The direct test detects cells
that were coated with antibody in vivo.

30

is there unexpected antibody to red cell antigens in the plasma of this potential recipient?

take red cells, add the plasma, rinse the cells, and then add antiglobulin.

If cells agglutinate, must have been AB to them in the plasma, because antiglobulin alone won’t react

indirect antiglobulin test (IAT)

31

IgG attack the RBC in the fetal circulation; the red blood cells are broken down and the fetus can develop reticulocytosis and anemia.

occurs in Rh(D)+ babies of Rh(D)- mothers

Hemolytic disease of the newborn

32

A newborn has a high bilirubin. He’s Rh(D)+
and mother is Rh(D)-

Hemolytic disease of the newborn is possible, but there are other causes of:

hyperbilirubinemia

33

HEMOLYTIC DISEASE OF THE NEWBORN (HDN) Rx

Give mother IgG antibody to Rh(D) Rh-immune globulin

basically causing autoimmune destruction of the AB you do not want

34

RhoGAM

used to prevent the immunological condition known as Rh disease (or hemolytic disease of newborn).

35

medicine is a solution of IgG anti-D (anti-RhD) antibodies that take out any fetal RhD-positive erythrocytes which have entered the maternal blood stream from fetal circulation, before maternal immune system can react to them, thus preventing maternal sensitization

RhoGAM

36

Anti-Rh antibodies are usually IgG (being anti-proteins), and do cross the:

placenta

37

HETEROPHILE ANTIBODIES

antibodies induced by external antigens

Some cross-react with self-antigens. For example, in rheumatic fever

38

RhoGAM is a solution of IgG anti-D (anti-RhD) antibodies that take out any fetal RhD-positive erythrocytes which have entered the maternal blood stream from fetal circulation, before maternal immune system can react to them, thus preventing _________

maternal sensitization