Blood banking Exam 1

A Caucasian patient is determined to have anti-Fya. What
is the likelihood of finding compatible blood? All you know
is that the gene frequency for Fya is 0.43 in Caucasians.

Fyb = 1-Fya =0.57 You need to find homozygous Fyb
units (aka Fya negative). Frequency of Fyb
homozygous units is 0.57x0.57 = 0.32. The likelihood
of finding a Fya negative unit is 32% assuming a
Caucasian donor base.

A patient is found to have anti-Fya and anti-K. What is the
likelihood of finding compatible blood? Gene frequency
for K is 0.04 and k is 0.96 among Caucasian donors. likely hood of finding an Fya negative unit is 32%.

The likelihood of finding a K negative unit is (k)(k) or
0.96x0.96 = 0.92 or 92%. The likelihood of finding
Fya and K antigen negative units are 0.92x0.32 =
0.29 or 29%

If a patient has anti-Fya and anti-K (29%) how many
RBCs do you have to test to find 2 compatible
units?

2/0.29= 6.89...7 RBCs

Patient MK has anti-K and anti-S and
they are preop for surgery 2 days from now. The
doctor has ordered 4 RBCs to be on hold. How
many RBCs need to be screened if the frequency
of the antigens are: K=9% and S = 55%.

Doctor wants 4 RBCs

Negative frequencies:

K = 91%

S = 45%

Number of units desired/ product of the negative frequencies=

4/ (0.91 x 0.45) =

4/ (0.4095) = 9.77 à 10 RBCs

A patient has anti-Jka, -K, -c, and –Fyb and the doctor wants to have 3 RBCs on hold for surgery. Assuming the tech is searching in ABO compatible inventory calculate the number of units he/she will have to screen to find antigen negative RBCs. The frequency of the antigens in the caucasian population is: Jka =76%, K=9%, c=80%, and Fyb=83%.

So the doctor wants 3 RBCs.

Negative frequencies: 1- (positive frequency) = negative frequency.

Jka = 24%

K = 91%

Little c = 20%

Fyb = 17%

3/ (0.24 x 0.91 c 0.2 x 0.17) =

3/ (0.007) = 428.6à 429 RBCs 

very low likely hood

What is the inheritance pattern?

Autosomal dominant: Blood group B and O

Why: Trait appears in every generation and typically in a 3:4 ratio and sex doesn’t matter

Based on the ABO groups of the children, the father I-1 would have to be a B/O genotype since II-6 and 7 are O/O.

What is the inheritance pattern?

Autosomal recessive

Why: : traits appear in the 2^nd generation at a 1:4 ratio and unaffected by sex.

The mating between  II-3 and II-4 serves to demonstrate that Lu is recessive Lua and Lub and that the presence of the silent Lu allele is masked by the product of Lua or Lub at the phenotypic level.

What is the inheritance pattern?

Autosomal Codominant:

Why:Sex doesn’t matter. Usually present in every generation.

An individual carrying 2 unlike alleles for any given trait may show the effects of only one of them, or of both (zygosity).

What is the inheritance pattern?

Sex-linked dominant

Why:Affected males transmit the trait to all daughters and to no son’s (no X to give to boys only Ys)

Affected females (heterozygous) transmit to half of their children either sex

Affected females (homozygous) transmit to all of their children

What is the inheritance pattern?

Sex linked recessive

Why: incidence of the trait is much higher in males then females. Rare to have homozygous females

Trait is passed from affected male to all daughters

All daughters who are carriers will affect half of their subsequent sons

Trait is never passed directly from father to son only through female carriers

Where does mitosis occur

everywhere but the ovaries and testicles

Where does meiosis occur?

ovaries and testicles

what is an Amorph?

An allele that does not code for a useable protein

cis

same side

trans is

opposite side

Cis orientation lends itself to a protein that puts the C antigen a bit farther away from the D antigen, meaning?

its not adding steric hindrance

Trans location results in D and C antigens being close together which results in a weaker expression of the D antigen due to…

Steric hinderance

Suppressor

affects the expression of another gene, or genes, through gene interaction by mechanisms that are not fully understood

Regulator

a gene that codes for a product that is required before another gene’s product can be expressed. This may be a precursor

first line of defense in innate and natural immunity

• intact skin

• mucous membranes

• cilia

• cough reflex

• secretions

• ph

second line defense in natural and innate immunity

• phagocytic cells

• complement-alternative pathway

• cytokines

• acute inflammatory reaction

Third line of defense also known as aquired and adaptive immunity

• lymphocytes

• B cells

• antibodies

• complement-classic

• Cytokines

IgM

cold reacting at Room temp

Rarely causes hemolysis

IgG

React best at 37C

can cause hemolysis

IgA

allergic reactions

IgE

Hypersensitivity reactions

IgD

Antibody isotype on immature B cells

what makes IgM special

• IgM is large and cant cross placenta

• IgM is the first antibody detected

• IgM can agglutinate red cells in saline

What makes IgG special

• small

• can cross the placentas

• can bind complement and needs two igG

• cannot agglutinate RBC in saline

• reacts best at 37C

label a drawing of IgG

What does igM look like in vivo

Which phenotype(s) could NOT result from the mating of a Fy(a+b+) individual and Fy(a-b+) individual? Select all that apply. 

Fy(a-b-) and Fy(a+b-)

T/F, Translation is the process by with DNA is copied into RNA. 

False

T/F, Mitosis ends in 4 non-identical gametes each containing only 23 chromosomes.

False

Given the following antithetical pair. Determine the most probable zygosity.

Homozygous

+0 is

homozygous

++ is

heterozygous

Given the following antithetical pair. Determine the most probable zygosity.

heterozygous

Given the following antithetical pairs (color coded). Determine the zygosity. for Fya, Kpa, and P

Fya=homozygous

Kpa=heterozygous

P= not applicable

Complement is activated by all of the following except?

IgG4

Sarah has a trait that neither her two brother nor parents express. Sarah's three daughters also do not express the trait. What is the inheritance pattern?

Autosomal recessive

A patient is making antibodies against K, E, and Fya antigens. If this patient is making the antibody, the most common scenario is that the patient lack the antigens and was exposed to them by either transfusion or pregnancy. Which of the following phenotypes could this patient have?

E-e+, K-k+, Fy(a-b+)

Justin expresses a trait that his brother doesn't have. Justin's father and mother also do not express it but his maternal grandfather did. What is the possible inheritance pattern?

X-linked recessive

Which of the following are found on antigen presenting cells?

Class II MHC

A patient needs 3 RBCs that are negative for the K antigen and the Fyb antigen. The frequency of the K antigen is 9% and the frequency of the Fyb antigen is 83%. How many RBCs do you have to test in order to find the 3 RBCs?

20

All of the following are involved in the acquired or adaptive immune response except?

Phagocytosis

Innate or natural immunity involves which of the following?

All answers are correct

Which of the following IgG subclasses is best at activating the complement cascade? 

3

T/F, IgM is the most efficient immunoglobulin at activating the complement cascade.

True

In a primary immune response, which antibody is developed first?

IgM

Complement binds to what part of an IgG molecule?

CH2

T/F, A mature B cell or plasma cell can make antibodies against several different epitopes

False

T/F, It takes two IgG molecules to activate complement.

True

T/F, The complement cascade remains activated in an EDTA tube. 

False

Which immunoglobulin(s) can activate the classic pathway of the complement cascade?

IgG1, IgG3, and IgM

All of the following are lymphocytes except _______?

PMNs

Step one of the complement cascade

Antibody (2xIgG or IgM) binds to antigen

Step 2 of the complement cascade

C1qrs binds to two Fc regions of the antibody(ies)

Step 3 of the complement cascade

C1q catalyzes C1r which activates C1s

step 4 of the complement cascade

C1s acts on C2 and C4 to form C4b2a (C3 convertase)

step 5 of the complement cascade

C3a is released and C4b2a3b (C5 convertase) is formed

step 6 of the complement cascade

C5-->C5b-->C6-->C7-->C8-->C9 = C5b6789 (MAC)

Two drops serum and one drop A1 cells, and two drops serum and one drop B cells are added to two tubes and centrifuged. The two tubes show reactivity when read macroscopically. This is an example of: 

reverse type

Mixed field agglutination in ABO forward grouping may be caused by...

A3 subgroup and transfusion of the wrong blood type to someone

T/F, Antibody-antigen reactions are irreversible chemical reactions.

False

T/F, IgG antibodies can cross the placenta.

True

A new tech makes a cell suspension that is 50%. The suspension is dripped to perform the forward grouping. Plasma is also dripped for the back grouping along with reagent red cells. The results are as follows. This is an example of _______.

Post zone

What do LISS, PEG, Albumin, and enzymes have in common? 

All answers are correct

This blood group types as an O and reacts negatively when tested with lectin Ulex europaeus. What is it?

type Oh, or Bombay

A patient has the following reactions in his front and back groupings. What terminal sugar does this patient have on his precursor substance?

N-acetylgalactosamine

If you were to describe the percentage of A1 types to A subgroups it would be....?

80% A1 and 20% A subgroup

A donor has the following genotype: A/O, Hh, and Sese. What will the donor have in his secretions?

H and A type 1 precursor substance

antigen

substance that is recognized as foreign, can cause an immune response

antibody

protein secreted by a plasma cell in response to interaction with an antigen

alloantibody

an antibody produced in one individual against the RBC antigens of anther individual

autoantibody

antibody reactive toward ones own RBC antigen

what can cause agglutination enhancements

• concentration

• centrifugation

• pH

• temperatue

• antibody isotype

• ionic strength

• law of mass action

igm is an _____ spin phase

immediate

igG is a ______ phase (37C)

antiglobulin

least sensitive potentiators

• saline

• albumin

Medium sensitive potentiators

• LISS

• PEG

• GEL/Solid phase

highest sensitivity potentiator and its issue

enzymes

issue: destroys some antigens

steps for agglutination reaction

1. sensitization

2. opsonization

3. lattice formation

4. agglutination

Prozone

antibody excess

Equivalence

optimum proportions of antigen and antibody

post zone

antigen excess

post zone

A 50% RBC suspension would cause what to be in excess?

antigen

If a patient has anti-Fya and anti-Jka how many RBCs do you have to test to find 2 compatible units? (Frequency Fya+ = 66%, Jka = 77%)

26

If a patient has anti-K and anti-Fyb and anti-s how many
RBCs do you have to test to find 2 compatible units? (Frequency K+= 9%, Fyb+ = 83%, s+ =89% )

118

H antigen sugar

L-Fucose

H antigen transferase

L-Fucosyltransferase

A antigen transferase

N-Acetylgalactosaminyltransferase

A antigen sugar

N- Aceltylgalactosamine

B antigen transferase

D-galactosyltransferase

B antigen sugar

D-galactose

List H from greatest to least…

0 > A2> B> A2B> A1> A1B

Oh, A 2, B you are meAnt 2 Be, A one and only, A1B

AB is the universal

plasma donor

O is the universal

RBC donor

Which of the following situations is most likely to cause
intravascular hemolysis when an incompatible transfusion
is given?

Group B packed cells to a group O recipient