BB Flashcards
is the study of blood group antigens and antibodies, HLA antigens and antibodies, pretransfusion testing, identification of unexpected alloantibodies, immune hemolysis, autoantibodies, drugs, blood collection, blood components, cryopreservation of blood, transfusion transmitted viruses, tissue banking and organ transplantation, blood transfusion practice, safety, quality assessment, records, blood inventory management, and blood usage review.
Immunohematology
foreign molecules that bind specifically to an antibody or a T-cell receptor.
Antigen
ells or tissue from a genetically different individual.
Allogeneic
cells or tissue from self.
Autologous
small-molecular-weight particle that requires a carrier molecule to be recognized by the immune system
Hapten
study of blood group antigens and antibodies.
Immunohematology
lymphocytes that mature in the bone marrow, differentiate into plasma cells when stimulated by an antigen, and produce antibodies.
B lymphocytes (B cells)
lymphocytes that mature in the thymus and produce cytokines to activate the immune cells including the B cell.
T lymphocytes (T cells)
secreted proteins that regulate the activity of other cells by binding to specific receptors. They can increase or decrease cell proliferation, antibody production, and inflammation reactions.
Cytokines
B cells produced after the first exposure that remain in the circulation and can recognize and respond to an antigen faster.
Memory B cells
antibody-producing B cells that have reached the end of their differentiating pathway.
Plasma cells
sites on an antigen that are recognized and bound by a particular antibody or T-cell receptor (also called epitopes).
Antigenic determinants
single antigenic determinants; functionally, they are the parts of the antigen that combine with the antibody.
Epitopes
family of cells or organisms having genetically identical constitution.
Clone
antigen in its role of eliciting an immune response.
Immunogen
simple sugars, such as monosaccharides and starches (polysaccharides).
Carbohydrates
fatty acids and glycerol compounds.
Lipids
is an antigen that provokes the immune response. Not all antigens are immunogens.
immunogen
glycoprotein (immunoglobulin) that recognizes a particular epitope on an antigen and facilitates clearance of that antigen.
Antibody
antibody; glycoprotein secreted by plasma cells that binds to specific epitopes on antigenic substances.
Immunoglobulin
larger polypeptides of an antibody molecule composed of a variable and constant region; five major classes of heavy chains determine the isotype of an antibody.
Heavy chains
smaller polypeptides of an antibody molecule composed of a variable and constant region; two major types of light chains exist in humans (kappa and lambda).
Light chains
one of five types of immunoglobulins determined by the heavy chain: IgM, IgG, IgA, IgE, and IgD.
Isotype
one of the two types of light chains that make up an immunoglobulin.
Kappa chains
one of the two types of light chains that make up an immunoglobulin.
Lambda chains
one of the two types of light chains that make up an immunoglobulin.
Lambda chains
amino-terminal portions of immunoglobulins and T-cell receptor chains that are highly variable and responsible for the antigenic specificity of these molecules.
Variable regions
non-variable portions of the heavy and light chains of an immunoglobulin.
Constant regions
variable part of an antibody or T-cell receptor; the antigen-binding site.
Idiotope
portion of the immunoglobulin heavy chains between the Fc and Fab region; provides flexibility to the molecule to allow two antigen-binding sites to function independently.
Hinge region
red cell destruction by phagocytes residing in the liver and spleen usually facilitated by IgG opsonization.
Extravascular hemolysis
number of epitopes per molecule of antigen.
Valency
red cell lyses occurring within the blood vessels usually by IgM activation of complement.
Intravascular hemolysis
having a combining power of two.
Bivalent
condition caused by destruction of fetal orneonatal red cells by maternal antibodies.
Hemolytic disease of the fetus and newborn
immune response induced by initial exposure to the antigen.
Primary immune response
method is necessary to detect antigen-antibody complexes involving IgG antibodies in vitro.
antiglobulin test
process of somatic mutations in the immunoglobulin gene causing the formation of variations in the affinity of the antibody to the antigen. B cells with the highest affinity are “selected” for the best fit, and the resulting antibody is stronger38. Secondary
immune response: immune response induced after a second exposure to the antigen, which activates the memory lymphocytes for a quicker response.
Affinity maturation
secondary immune response. Multiple stimulations of the immune system with the same antigen produce antibodies with increased binding strength as a result of affinity maturation.
Anamnestic response
complex of one or more antibody molecules bound to an antigen.
Immune complex
strength of the binding between a single antibody and an epitope of an antigen.
Affinity
overall strength of reaction between several epitopes and antibodies; depends on the affinity of the antibody, valency, and noncovalent attractive forces.
Avidity
compounds containing carbohydrate and protein molecules.
Glycoproteins
compounds containing carbohydrate and lipid molecules.
Glycolipids
visible clumping of particulate antigens caused by interaction with a specific antibody.
Agglutination
antibodies with specificities other than self; stimulated by transfusion or pregnancy.
Alloantibodies
test to determine the presence of alloantibodies.
Antibody screen test
group of serum proteins that participate in an enzymatic cascade, ultimately generating the membrane attack complex that causes lysis of cellular elements.
Complement system
C5 to C9 proteins of the complement system that mediate cell lysis in the target cell.
Membrane attack complex
lysis or rupture of erythrocytes.
Hemolysis
activation of complement that is initiated by antigen-antibody complexes.
Classical pathway
activation of complement that is initiated by foreign cell-surface constituents.
Alternative pathway
complement split products (C3a, C4a, and C5a) that mediate degranulation of mast cells and basophils, which results in smooth muscle contraction and increased vascular permeability.
Anaphylatoxins
products such as histamines released by basophils, mast cells, and platelets that act on the endothelium and smooth muscle of the local vasculature.
Vasoactive amines
movement of cells in the direction of the antigenic stimulus.
Chemotactic
substance (antibody or complement protein) that binds to an antigen and enhances phagocytosis.
Opsonin
molecules on the cell surface that have a high affinity for a particular ligand.
Receptors
system of mononuclear phagocytic cells, associated with the liver, spleen, and lymph nodes, that clears microbes and damaged cells.
Mononuclear phagocyte system
binding of antibody or complement components to a red cell.
Sensitization
combination of antibody and a multivalent antigen to form cross-links and result in visible agglutination.
Lattice formation
ratio of antigen on the red cell to antibody in the serum.
Serum-to-cell ratio
interpretation of agglutination reactions immediately after centrifugation and without incubation.
Immediate-spin
electrostatic potential measured between the red cell membrane and the slipping plane of the same cell.
Zeta potential
number of binding sites of multivalent antigen and antibody are approximately equal.
Zone of equivalence
excess antibody causing a false-negative reaction.
Prozone
excess antigen causing a false-negative reaction.
Postzone
fluid above cells or particles after centrifugation.
Supernatant
unresponsiveness to platelet transfusions owing to HLA-specific or platelet-specific antibodies or platelet destruction from fever or sepsis. Responsiveness is measured by posttransfusion platelet counts.
Refractoriness
set of linked genes inherited together because of their close proximity on a chromosome.
Haplotype
different forms of a gene present at a particular chromosomal locus.
Alleles
genetic system that expresses several possible alleles at specific loci on a chromosome.
Polymorphic
antibody destruction of a newborn’s platelets caused by antibodies formed from prior pregnancies and directed to paternal antigens.
Neonatal alloimmune thrombocytopenia
antibodies with specificities other than self; stimulated by transfusion or pregnancy.
Alloantibodies
antibody destruction of platelets after transfusion.
Posttransfusion purpura
First time a blood transfusion was recorded in history.
Pope Innocent VII
Sodium phosphate
Braxton Hicks
ABO blood groups
Karl Landsteiner
Vein to vein transfusion
Edward E. Lindemann
Syringe-valve apparatus
Unger
Sodium citrate
Hustin
Minimum amount of citrate needed for anticoagulation
Lewisohn
Citrate dextrose solution
Rous and Turner
Techniques in blood transfusion and blood preservation
Dr. Charles Drew
Introduced the formula for the preservative acid-citrate dextrose
Loutit and Mollison
Introduced citrate-phosphate dextrose
Gibson
The amount of whole blood in a unit has been______of blood
450 mL +/- 10%
For a____donor, a maximum of_____ can be collected
110 lb, 525 mL
Total blood volume for most adults
10 to 12 pints
Donors can replenish the fluid lost from the donation of
1 pint in 24 hours
The donor’s red cells are replaced within_____after donation.
1 to 2 months
A volunteer donor can donate blood every, every what week?
8 weeks
What are the units of the whole blood can be separated into three components?
Packed red blood cells, platelets, and plasma
The plasma can be converted by_______to a clotting factor concentrate that is rich in antihemophilic factor.
cryoprecipitation
A unit of whole blood-prepared RBCs may be stored for
21 to 42 days
THE DONATION PROCESS
Educational material that contains information on the risks of infectious diseases transmitted by blood transfusion, including the symptoms and sign of AIDS, is given to each prospective donor to read.
Step 1: Educational Materials
A uniform donor history questionnaire, designed to ask questions that protect the health of both the donor and the recipient, is given to every donor. The health history questionnaire is used to identify donors who have been exposed to diseases that can be transmitted in blood.
Step 2: The Donor Health History Questionnaire
The abbreviated physical examination for donors includes blood pressure, pulse, and temperature readings; hemoglobin or hematocrit level; and the inspection of the arms for skin lesions.
Step 3: The Abbreviated Physical Examination
Syphilis
1950’s
Hepatitis B surface antigen (HbsAg)
1971
Hepatitis B core antibody (anti-HBc)
1986
Hepatitis C virus antibody (anti-HCV
1990
Human immunodeficiency virus antibodies (anti- HIV-1/2)
1992
Human T cell lymphotropic virus
19972
NAT-nucleic acid amplification testing, **Initially under IND starting in
1999
Anti-HIV-1 testing implemented
1985
Anti-HTLV testing implemented
1988
Three areas of RBC biology are crucial for normal erythrocyte survival function:
- Normal chemical composition and structure of the RBC membrane
- Hemoglobin structure and function
- RBC metabolism
main lipid component of the membrane, arranged in a bilayer structure comprising the framework in which globular proteins traverse and move.
Phospholipids
The biochemical composition of the RBC membrane is approximately
52% protein, 40% lipid, and 8% carbohydrate.
The loss of RBC membrane is exemplified by the formation of spherocytes (no central pallor) and bite cells.
Deformability
Human immunodeficiency virus (HIV-1) (NAT)
Hepatitis C Virus (HCV) (NAT)
1999
Hepatitis C Virus (HCV) (NAT)
2004
Trypanosoma cruzi antibody (anti-T. cruzi)
2007
Hepatitis B virus (HBV) NAT
2009
Babesia microti antibody and NAT (recommended)
2012
Zika virus NAT
2016
The RBC membrane is freely permeable to water and anions.
* The RBC membrane is relatively impermeable to cations such as sodium and potassium
* The erythrocyte intracellular-to- extracellular ratios for Na+ and K+ are 1:12 and 25:1, respectively
Permeability
Goal of Blood preservation: To provide viable and functional blood components for patients requiring blood transfusion.
* To maintain optimum viability, blood is stored in the liquid state between 1oC and 6oC for a specific number of days, as determined by the preservative solution(s) used.
* The loss of RBC viability has been correlated with the “lesion of storage” which is associated with various biochemical changes.
RBC PRESERVATION
RBC Storage Lesion
CHARACTERISTIC
% Viable Cells
Glucose
ATP
Lactic Acid
pH
2,3-DPG
Oxygen Dissociation Curve
Plasma K+
Plasma hemoglobin
CHANGE OBSERVED
Decreased
Decreased
Decreased
Increased
Decreased
Decreased
Shift to the Left
Increased
Increased
Adenine supplemented blood can be stored at
1 to 6 degrees Celsius for 35 days
chelates calcium; prevents clotting 2.
Citrate
maintains pH during storage
Monobasic sodium phosphate
Substrate for ATP production
Dextrose
Production of ATP
Adenine
Acid Citrate-Dextrose
(formula A)*
ABBR. STORAGE TIME (DAYS)
ACD-A 21
Citrate-phosphate dextrose
ABBR. STORAGE TIME (DAYS)
CPD 21
Citrate-phosphate-double
dextrose
ABBR. STORAGE TIME (DAYS)
CP2D 21
Citrate-phosphate-dextrose adenine
ABBR. STORAGE TIME (DAYS)
CPDA-1 35
Preserving solutions that are added to the RBCs
after removal of the plasma with or without
platelets.
ADDITIVE SOLUTIONS
In additive solutions, how many hematocrit will decrease?
70% to 85% to around 50% to 60%
What are the benefits of RBC Additive Solutions?
- Extends the shelf-life of RBCs to 42 days by
adding nutrients - Allows for the harvesting of more plasma and
platelets from the unit - Produces an RBC concentrate of lower
viscosity that is easier to infuse
Used for autologous units and storage of rare
blood types.
* It involves the addition of a cryoprotective agent
to RBCs that are less than 6 days old
* Currently, the FDA licenses frozen RBCs for a
period of 10 years from the date of freezing; that
is, frozen RBCs may be stored up to 10 years
before thawing and transfusion.
RBC FREEZING
Rejuvenation of RBCs is the process by which ATP
and 2,3-DPG levels are restored or enhanced by
metabolic alterations.
* FDA-approved rejuvenation solution contains
phosphate, inosine, and adenine
* RBCs may be prepared up to three days after
expiration when stored in CPD, CPDA-1, and AS-
1 storage solutions.
RBC REJUVENATION
currently the only FDA approved
rejuvenation solution sold in the US.
Rejuvesol
- Platelets are involved in the blood coagulation
process and are given to treat or prevent
bleeding. They are given either therapeutically to
stop bleeding or prophylactically to prevent
bleeding. - Platelets are intimately involved in primary
hemostasis, which is the interaction of platelets
and the vascular endothelium in halting and
preventing bleeding following vascular injury. - The role of platelets in hemostasis includes:
1. initial arrest of bleeding by platelet plug
formation
2. stabilization of the hemostatic plug by
contributing to the process of fibrin formation
3. maintenance of vascular integrity.
PLATELET PRESERVATION
Platelets are stored at 20°C to 24°C with
maintaining continuous gentle agitation
throughout the storage period of 5 days
* The loss of platelet quality during storage is
known as the platelet storage lesion.
Platelet Storage Lesion
Factors to be considered when using 5-day plastic
storage bags
- Temperature control of 20°C to 24°C is critical
during platelet preparation and storage. - Careful handling of plastic bags during expression
of platelet-poor plasma helps prevent the platelet
button from being distributed and prevents
removal of excess platelets with the platelet-poor
plasma. - Residual plasma volumes recommended for the
storage of platelet concentrates from whole blood
(45 to 65 mL). - For apheresis platelets, the surface area of the
storage bags needs to allow for the number of
platelets that will be stored.
A platelet concentrate should contain a minimum
of
5.5 X 1010/L platelets in a volume routinely
between 45 and 65 mL that is sufficient to
maintain a pH of 6.2 or greater at the conclusion
of the 5-day storage period.
When platelet concentrates are pooled using an
open system, the storage time changes
to 4
hours.
Apheresis components contain
4 to 6 times as
many platelets as a PC prepared from whole
blood.
Platelet components are stored for
up to 5 days
at 20-24 C.
When necessary, as during shipping, platelets
can be stored without continuous agitation for up
to
24 hours at 20-24oC during a 5-day storage
period
Platelets are rarely stored at
1 to 6 degrees
Celsius.
If a platelet bag is broken or opened, the platelets
must be transfused within
4 hours when stored
at 20 to 24 degrees Celsius.
System for continuous
temp. monitoring and audible alarm
Blood storage refrigerators and freezers,
platelet incubators
compare against
thermometer daily. Calibrate as necessary.
Temperature recorder
Check high and low temp. of activation
quarterly
Alarms
Check temperature daily
Waterbath
Check temperature daily.
Periodically check each well
Heat blocks
Determine optimum speed and
time for different procedures upon receipt, after
repairs and periodically. Check timer every 3
months, RPM every 6 months (with tachometer).
Centrifuges
Check tube fill level daily, AHG
volume monthly. Verify time and speed quarterly.
Calibrate quarterly
Cell washers
Calibrate quarterly
Pipettes
Test with positive and negative
controls each day of use. Use heterozygous cells
for positive controls.
Antisera
Check for hemolysis. Test each
day of use with positive and negative controls.
Reagent Cells
Check anti-IgG activity
each day of use by testing Rh-pos cells sensitized
with anti-D.
Antihuman globulin
Study of transmission of inherited
characteristics.
Genetics
groups of related RBC antigens
inherited according to Mendelian genetics
Blood group systems
Physical, observable expression of inherited
traits; detectable products
Phenotype
Inherited genes; actual genetic makeup
Genotype
Visual map that displays a family history
and can display inheritance patterns for individual traits
Pedigree chart
Smallest unit of inheritance
Gene
Site on chromosome where specific
genes are located
Genetic locus
Alternative forms of a gene
Alleles
Opposite form of a gene, different allele
Antithetical
Having two or more possible alleles at a
locus
Polymorphic
Equal expression of both alleles in
phenotype
Codominant
Genes expressed with equal frequency in
males and females, on non-sex
chromosome
Autosomal
Set of genes inherited via one of the two
parental gametes
Haplotype
Genes that do not produce a detectable
product
Amorph
Identical alleles at the same gene locus
from both parents
Homozygous
Different alleles at the same gene locus
from each parent
Heterozygous
Agglutination reactions are generally
stronger for homozygous cells and slightly weaker for
heterozygous cells.
Dosage Effect
Genes are inherited on the same chromosome
Cis
Genes are inherited on separate chromosomes.
Genes inherited in transposition can weaken the trait’s
expression.
Trans
states that
factors for different characteristics are inherited in
dependent of each other if they reside on different
chromosomes.
Mendel’s law of independent assortment
is the process by which somatic cells divide, with
an end result of two identical daughtercells
Mitosis
is the cell division process that takes place in
germ cells that concludes in the production of haploid
gametes, with an end result of four unique daughter cells.
Meiosis
refers to any structural alteration of DNA in an
organism (mutant) that is caused by a physical or
chemical agent (mutagen) and can occur spontaneously.
Mutations
is an enzymatic process whereby genetic
information in a DNA strand is copied into an mRNA
complementary strand.
Transcription
is the complex process by which mRNA,
which contains a mobile version of the DNA template
encoding the genes for an organism
Translation
