1S [LEC]: Intro + History Flashcards
In 1492, blood was taken from three young men and given to the stricken ___ in the hope of curing him
Pope Innocent VII
In 1869, ___ recommended sodium phosphate as a safe anticoagulant
Braxton Hicks
In 1901, ___ discovered the ABO blood groups
Karl Landsteiner
___ carried out vein-to-vein transfusion of blood by using multiple syringes and a special cannula for puncturing the vein through the skin
Edward E. Lindemann
___ designed his syringe-valve apparatus that transfusions from donor to patient by an unassisted physician became practical
Unger
In 1914, ___ reported the use of sodium citrate as an anticoagulant solution for transfusions
Hustin
In 1915, ___ determined the minimum amount of citrate needed for anticoagulation and demonstrated its nontoxicity in small amounts
Lewisohn
Mechanism of action of citrate as an anticoagulant
Chelates calcium
In 1916, ___ and __ introduced a citrate-dextrose solution for the preservation of blood
Rous and Turner
The function of glucose in RBC metabolism was not understood until the ___
1930s
In February 1941, ___ was appointed director of the first American Red Cross blood bank at Presbyterian Hospital
Dr. Charles Drew
In 1943, ___ and ___ of England introduced the formula for the preservative acid-citrate-dextrose (ACD)
Loutit and Mollison
In July 1947, what journal on blood preservation was published?
Journal of Clinical Investigation
In 1957, ___ introduced an improved peservative solution called citrate-phosphate dextrose (CPD)
Gibson
A citizen seeking spiritual rebirth descended into a pit, or fossa sanguinis
Taurobolium
The ___ bathed in blood to resuscitate the sick and rejuvenate the old
Egyptians
In 1666, ___ was the first to successfully transfuse blood from one animal to another (dogs)
Richard Lower
In 1667, ___ performed animal (sheep) to man transfusion
Richard Lower
The first man to received blood from an animal (sheep)
Arthur Coga
In 1667, ___ is documented as the first one to perform animal to man transfusion
Jean-Baptiste Denis
In 1667, ___ successfully transfused sheep blood into a 15 y/o with long-standing fever
Jean-Baptiste Denis
Substance that reacts to antibody
Antigen
The product of antigenic stimulation
Antibody
T/F: All blood groups are immunogen
True
Most immunogenic blood antigen
A, B
Second most immunogenic blood antigen
RhD
Third most immunogenic blood antigen
K (Kell)
Foreign molecules that bind specifically to an antibody or a T-cell receptor
Antigen
Antigen in its role of eliciting an immune response
Immunogen
Glycoprotein that recognizes a particular epitope on an antigen and facilitates clearance of that antigen
Antibody
The component of an immunoglobulin that connects the monomers
J chain
The name of the immunoglobulin depends on the ___
Heavy-chain composition
The agglutinating antibody
IgM
How many molecules of IgM are needed to activate complement?
1
Temperature of binding of IgM
20-24C or colder
The immunoglobulin capable of passing through the placenta
IgG
Temperature of binding of IgG
37C (body temp)
How many molecules of IgG is needed to activate complement?
2
The coating antibody
IgG
Light-chain composition of the antibodies
Kappa and Lambda
The smallest antibody
IgG
The ratio of kappa to lambda
2:1
Identify the antibody:
Capable of destroying transfused antigen-positive RBCs
IgG
Identify the antibody:
Predominant Ab produced in the secondary response
IgG
Subclass of IgG that is best in passing through placenta
IgG1
Subclass of IgG that is the worst in passing through placenta
IgG2
Subclass of IgG that is best in complement activation
IgG3
Subclass of IgG that is the worst in complement activation
IgG4
Identify the antibody:
Rh, Duffy, Kidd, Kell
IgG
Identify the antibody:
Most commonly encountered naturally occurring Ab (ABO system)
IgM
Identify the antibody:
Produced in response to commonly occurring antigens such as intestinal flora and pollen grains
IgM
Identify the antibody:
ABO, Lewis, Ii, P, MN
IgM
Identify the antibody:
Can interfere with detecting IgG by masking their reactivity
IgM
Can exist in monomeric or pentameric form with J chain
IgM
The IgM form present in the surface of B cells
monomeric
The IgM form present in serum
pentameric
Identify the antibody:
Exist as monomer, dimer, or trimer joined by J chain
IgA
Identify the antibody:
For mucosal immunity and secretions
IgA
Identify the antibody:
30% of anti-A and anti-B
IgA
Identify the antibody:
May cause severe anaphylaxis
IgA
Identify the antibody:
Can increase the effect of IgG-induced RBC hemolysis
IgA
Identify the antibody:
May cause urticaria if transfused in patients with severe allergic reactions
IgE
Identify the antibody:
Releases histamines
IgE
Form of IgE most commonly seen in secretions
dimer
Identify the antibody:
Least significant in blood banking
IgD
Identify the antibody:
Found in the surface of B cells
IgD
Identify the antibody:
Not able to cross placenta and activate complement
IgD
Antibodies derived from more than one antibody-producing parent cell
Polyclonal
Produced in response to a single antigen with more than one epitope
Polyclonal
Heterogenous antibody against the same antigen
Polyclonal
Antibodies derived from a single ancestral antibody-producing parent cell
Monoclonal
Preferred in testing; highly specific, well-characterized, and uniformly reactive
Monoclonal
The antigen-binding site
Epitope
The antibody-binding site
Paratope
Type of alloantibody:
Found in individuals without previous exposure to RBC antigens from transfusions, injection, or pregnancy
Naturally occurring
Type of alloantibody:
ABH, Hh, Ii, Lewis, MN, P
Naturally occurring
Type of alloantibody:
Mostly IgM cold agglutinins
Naturally occurring
Type of alloantibody:
Needed for serum typing
Naturally occurring
Type of alloantibody:
Found in individuals with previous exposure to transfusion, injection, and pregnancy
Immune
Type of alloantibody:
Mostly IgG
Immune
Type of alloantibody:
Rh, Duffy, Kidd, Kell, Ss
Immune
Type of serological test done in naturally occurring alloantibody
Indirect/ Reverse/ Backward
Type of serological test done in immune alloantibody
Direct/ Forward
Type of alloantibody:
Reacts in saline at ambient room temp or at 4C
Naturally occurring (IgM antibody)
Type of alloantibody:
May cause hemolysis at 37C
Naturally occurring (IgG antibody)
Type of alloantibody:
Reacts best at 37C
Immune
Type of alloantibody:
Requires AHG (Coomb’s) sera for detection
Immune
Type of antibody:
Produced after exposure to non-self antigens
Alloantibodies
Type of antibody:
Produced in response to self-antigens
Autoantibodies
Type of antibody:
Transfused px with undetectable alloAb may elicit a stronger immune response against previous Ags and cause severe transfusion rxns
Autoantibodies
Type of antibody:
Positive autocontrol or direct antiglobulin test (DAT)
Autoantibodies
Type of antibody:
Targets antigen absent to px’s red cell
Alloantibodies
Type of antibody:
Targets antigen present to px’s red cell
Autoantibodies
This test differentiates alloantibody from autoantibody
Autocontrol
Components of autocontrol testing
px’s red cell + px’s serum
Positive result for autocontrol test
Agglutination
The antigen-antibody or immune complex is also called as ___
epitope-paratope complex
Complex of one or more antibody molecules bound to an antigen
Immune complex
The extend of the reciprocal relationship (fit) between the antigen and its binding site on the antibody
Lock and key mechanism
Factors influencing antigen-antibody reactions
- intermolecular binding forces
- antibody properties
- host factors
- tolerance
Intermolecular binding force:
Attraction between two molecules on the basis of opposite charge
Electrostatic forces (ionic binding)
Intermolecular binding force:
A positively charged region of a molecule is attracted to the negatively charged region of another molecule
Electrostatic forces (ionic binding)
Intermolecular binding force:
Attraction of two negatively charged groups (X-) for a H+ atom
Hydrogen binding
Intermolecular binding force:
Weak bonds formed as a result of the exclusion of water from the antigen-antibody complex
Hydrophobic bonding
Intermolecular binding force:
Attraction between the electron cloud (-) of one atom and the protons (+) within the nucleus of another atom
van der Waals forces
Antibody property:
Strength of the binding between a single antibody and an epitope of an antigen
Affinity
Antibody property:
Overall strength of reaction between several epitopes and antibodies; depends on the affinity of antibody, valency, and noncovalent attractive forces
Avidity
Antibody property:
Number of epitopes per molecule of antigen
Valency
High avidity = ___ dissociation
Low
One of the most important characteristics of an antibody that is related to its relative avidity for antigen
Specificity
A characteristic of an antibody that produces a reaction to similar antigen
Cross reactivity
Defined as the lack of an immune response or an active immunosuppressive response
Tolerance
Exposure to an antigen during fetal life
Chimera
Presence of different populations of cells in a single individual
Chimera
Prevents D-negative mothers from developing anti-D antibodies after delivering Rh-positive infants
Tolerance
The most common complement pathway where there is an antigen-antibody reaction
Classical pathway
A complement pathway where the membrane property of a microorganism is involved
Alternative pathway
The antigen-antibody complex is removed from the body’s circulation through the ___
Mononuclear phagocyte system
In vitro RBC Ag-Ab reactions are detected by visible ___
Agglutination (hemagglutination) or hemolysis
Result of complement activation
Lysis (hemolysis)
Stage of hemagglutination:
Attachment of Ab to corresponding Ag on RBC membrane
Sensitization
Stage of hemagglutination:
Combination of antibody and a multivalent antigen to form crosslinks
Lattice formation
Lattice formation is improved by ___
Centrifugation
Factors that influence agglutination
Centrifugation
Ag-Ab ratio
pH
Temperature
Ig type
Enhancement media
Factors that influence agglutination:
Enhances agglutination reactions
Centrifugation
Factors that influence agglutination
Decreases reaction time by increasing the gravitational forces on the reactants to bringing reactants closer together
Centrifugation
Ag-Ab ratio:
Excess Ag
Postzone (false neg)
Ag-Ab ratio:
Excess Ab
Prozone (false neg)
Ideal pH for Ag-Ab reactions
6.5-7.5
T/F:
Anti-M and Anti-Pr (Sp1) reacts at a higher pH
False (lower pH)
Ig type:
Can readily agglutinate RBCs in saline than IgG
IgM
Ig type:
Has more Ag-combining sites
IgM
Ig type:
Cold reacting
IgM
Ig type:
ABO Abs
IgM
Ig type:
Warm reacting
IgG
Ig type:
Rh Abs
IgG
A biphasic antibody, causing Donath-Landsteiner hemolytic anemia
autoanti-P
Difference in negative charge between the inner and outer surfaces of the cloud
Zeta potential
Higher zeta potential = ___ Distance
Higher
T/F: The higher the zeta potential, the more difficult for RBCs to agglutinate
True
Decreases ZP by increasing dielectric constant or adding more cations
Protein media
Protein media:
Cheapest but longest incubation time
Bovine serum albumin (BSA)
Protein media:
Removes excess water and doesn’t need centrifugation
Polyethylene glycol (PEG)
If centrifugation is done when using PEG as a protein media, there is a possibility of ___ in the result
false positive
Protein media:
Most commonly used with shortest incubation time of 5-15 mins; ave. 10 mins
Low ionic strength solution (LISS)
NaCl concentration of LISS
0.2%
In using LISS as a protein media, the higher the rate of Ab uptake = ___ incubation time
lower
In using LISS as a protein media, when the rate of Ab uptake is increased the incubation time is improved from ___ to ___ mins
30-60 mins to 5-15 mins
Incubation time of PEG
10-30 mins
Mechanism of action of proteolytic enzymes as enhancement media
Cleaves sialic acid from RBC membrane
Identify the proteolytic enzyme used in BB:
Isolated from fig plants
Ficin
Identify the proteolytic enzyme used in BB:
From papaya
Papain
Identify the proteolytic enzyme used in BB:
From pig stomach
Trypsin
Identify the proteolytic enzyme used in BB:
From pineapple
Bromelin
Blood antigens enhanced by proteolytic enzymes
Rh, Kidd, P1, Lewis, I Ags
Blood antigens depressed by proteolytic enzymes
MNSs, Duffy Ags
An enhancement media that determines if RBCs are coated with Ab and/or complement
Anti-human globulin (AHG) reagents
An enhancement media that acts as a bridge
Anti-human globulin (AHG) reagents
T/F: In using AHG reagents, small IgG can both sensitize and cause agglutination
False (they rarely cause agglutination and cannot overcome zeta potential)
Components of LISS
0.2% NaCl
Glycine (to prevent cell lysis)
Introduced direct blood transfusion using two silver cannulae
James Aveling
