Immunological Principles Flashcards
Organs, cells, proteins, and other molecules comprise the ___________ ___________.
Immune system
True or false? The immune system is poor at adapting.
False
Which first line of defence does the following describe? ‘Also called the natural immune system, non-specific, with phagocytic cells and chemical mediators promote to an inflammatory response, and concentrates cells of immune system at requisite sites in the body. It has no memory’.
Innate immune system
State three features of the adaptive immune system.
Second line of defence, has memory, and produces highly-specific antibodies
Humeral immunity refers to the immune response mediated by ___________.
Antibodies
Cellular immunity is mediated directly by cells of the immune system, such as macrophages, ___-lymphocytes, and natural killer (NK) cells
T
__________ (immunogens) are substances that are capable of inducing a specific immune response
Antigens
True or false? The larger the antigen, the stronger its immunogenic properties are.
True
Antigens may have many epitopes, leading to antibodies with different specificity and sensitivity. What is the definition of an epitope?
Antigenic determinant
___ antigens are lipoproteins.
Rh
_________ (gammaglobulins or immunoglobins (Igs)) are substances that are produced in response to immunogenic stimulation, and are capable of specific interaction with the provoking antigen.
Antibodies
State the five classes of antibodies.
IgA, IgD, IgE, IgG, and IgM
True or false? Antibodies bind to a specific antigen.
True
____ (~80% of total serum Igs) is a monomer, and smaller than an IgM, with two binding sites. It appears later in the immune response, and can cross placentae, as well as being present in all body fluids.
IgG
___(~6% of total serum Igs) is shaped like a pentamer, and is larger than an IgG, with ten binding sites. It is a forerunner in immune response, and cannot cross blood, placentae, and lymph.
IgM
IgA is often found in _________.
Secretions
The basic immunoglobin unit is composed of _______ polypeptide chains; two are identical light chains, the other two are identical heavy chains.
Four
Heavy chains denote ____ classes.
Ig
Light chains have only two factions: ______ and lambda (Λ).
Kappa (k)
The _____ fragment is the part of the antibody that binds to antigens, and is also the site of variable amino acid sequence occurrences.
Fab
The ___ fragment is where complement binds, together with anti-human globulin serum (anti-IgG).
Amino acid sequences in this area are constant, and unchanging among antibodies.
Fc
The ________ immune response follows an initial exposure to an antigen, and is of short duration and low magnitude.
Primary
Secondary responses follow repeated exposure and are of longer duration and ________ magnitude.
Greater
IgG antibodies are the _____ clinically significant, together with those that react at 37 degrees Celsius
Most
____ antibodies found in transfusion science are often ‘naturally-occurring’.
IgM
_______ antibodies, such as those of environmental origin, include Anti-A and Anti-B.
Natural
Immune antibodies are formed following a ________ or a pregnancy, through an immune response.
Transfusion
________ antibodies are a mixture of antibodies, secreted against a specific antigen, each recognising a different epitope, and are made by a number of B-cell clones (heterogenous).
Polyclonal
True or false? Human-made antibodies against blood group antigens tend not to be polyclonal.
False
Monoclonal antibodies are identical _________, directed against a specific epitope on an antigen.
Antibodies
Complete antibodies are capable of agglutinating cells suspended in ________.
Generally, IgM are complete.
Saline
Incomplete antibodies attach to the cell surface, but do not cause agglutination;
______ are generally incomplete.
IgG
What component of the immune system plays a leading role in cell lysis, opsonisation (coating of a foreign substance with complement to facilitate phagocytosis), production of split products, and anaphylaxis?
Complement
Name the three pathways by which complement may be activated.
Classic, lectin, and alternative
‘Activation of C1 leads to activation of C2 and C4. This leads to the activation of C3 (forms C3a and C3b). This activates C. This leads to the activation of C6, C7, C8, and C9, and the formation of the MAC. The end result is lysis of the target cell, or if the entire pathway is not activated, sensitisation of the target cells will happen. Sensitisation is the coating of an RBC with an antibody, complement, or both’. Which pathway does the passage outline?
Classic
What does the acronym ‘MAC’ represent?
Membrane attack complex
True or false? For commencement, all three pathways require antigen-antibody interactions.
False; only the classic pathway requires such an interaction
Complement can cause the in vivo destruction of _____, following an incompatible transfusion, if the antibody involved can bind complement.
RBC
Very few antibodies, such as Anti-___ and Anti-B, together with some rare antibodies, can cause a complete activation of the MAC.
A
All blood group antibodies, except ___ and MN antibodies, can activate the initial steps of the complement cascade
Rh
Antigen-antibody interactions cause activation of the first component of the classical pathway, ____.
C1q
During a negative antigen-antibody interaction, in-vivo ________ occurs, whereby rupture of RBC in the bloodstream occurs intravascularly.
Haemolysis
Extravascular haemolysis occurs when _________ of RBC by macrophages occurs, and involves antibodies unable to activate the whole complement cascade
Phagocytosis
Haemagglutination occurs in two phases: __________ and agglutination.
Sensitisation
True or false? Zeta potential is the electric potential across a solid liquid interface.
True
‘In RBC, the net potential is produced by the negative charges on the cell surface, and the positive charges in a cloud of cations forming a layer over the surface. It is responsible for a repelling force between RBC that resists agglutination’. To which potential does this passage refer?
Zeta
Hydration and surface tension involves __________ heads of phospholipids, which attract and orient water molecules, creating a surface effect.
Hydrophilic
State four factors which impact antigen-antibody reactions.
Temperature, pH, ionic strength, and zygosity
