Fundamentals of Immunology & Serology in Blood Banking Flashcards
It is the science that embodies the study of blood group antigens and antibodies.
Immunohematology
It is defined as the study of a host’s reactions when foreign substances are introduced into the body.
Immunology
It is the laboratory study of antigen-antibody reactions.
Serology
It includes tissues, organs, cells, and biological mediators that coordinate to defend a host organism against intrusion by a foreign substance or abnormal cells of self-origin.
Immune System
It confers protection from nonself and abnormal self-elements.
Immunity
It refers to anything that is derived from the host genome
Self
It refers to anything outside the host
Nonself
Characteristics of natural or innate immunity
- Resist infection by means of normally present body functions
- Nonadaptive and nonspecific
- Immediately available
- No memory
Natural immunity is made up of:
Physical & Biochemical barriers
Examples of physical barriers:
Intact skin
Mucous membranes
Cilia lining the mucous membranes
Cough reflexes
Examples of biochemical barriers:
bactericidal enzymes, fatty acids, sweat, digestive enzymes in saliva, stomach acid, and low pH
Cell that remove invading organisms by engulfing and digesting them with vesicle enzymes
Phagocytes
Two major phagocytic cells
Polymorphonuclear and mononuclear cells
Plasma components that coat pathogens and facilitate phagocytosis
Opsonins
Enzymes that are normally found in the plasma in a proenzyme inactive state
Complement system
3 major roles of complement system in immunity
- Final lysis of abnormal and pathogenic cells (binding of antibody)
- Opsonization and phagocytosis
- Mediation of inflammation
It is a type of resistance that is characterized by specificity for each individual pathogen or microbial agent.
Secondary (Adaptive, acquired immunity)
Type of immunity that is present only in vertebrates.
Secondary (Adaptive, acquired immunity)
Adaptive immunity relies on the formation of
Antigen-antibody complexes
It is mediated by various IS cells, such as macrophages, T cells, and dendritic cells.
Cellular immunity
Effector molecules that activate and deactivate different cells, which allows cells to communicate throughout the host body.
Lymphokines
It consists of the fluid parts of the immune system such as antibodies and complement components.
Humoral immunity
Physical components of natural immunity
Intact skin
Mucous membranes
Cilia
Cough reflex
Biochemical components of natural immunity
Sweat Tears Saliva Mucus Acid pH of vagina Stomach acid
Cellular components of natural immunity
Macrophages
Monocytes
PMNs
NK cells
Most potent macrophage
Dendritic cells
Humoral component of natural immunity
Complement proteins Cytokines (interferons, interleukins) Properdin Beta lysin Tumor necrosis factor Inflammation Fever
Cellular components of adaptive immunity
Lymphocytes (T cells, T helper, T cytotoxic, T memory cells B cells (B memory cells, plasma cells)
Humoral component of adaptive immunity
Immunoglobulins
It refers to foreign molecules that bind specifically to an antibody or a T-cell receptor.
Antigen
It refers to cells or tissue from a genetically different individual.
Allogenic
It refers to cells or tissue from self.
Autologous
It refers to small-molecular-weight particle that requires a carrier molecule to be recognized by the immune system.
Haptens
These are lymphocytes that mature in the bone marrow
B lymphocytes (B cells)
Cells that produce antibody
Plasma cells
These are lymphocytes that mature in the thymus and produce cytokines
T-lymphocytes (T cells)
What is the function of cytokines
To activate immune cells
Cells that increase or decrease cell proliferation, antibody production, and inflammation reactions.
Cytokines
Large granular lymphocytes that kills virally infected cells and tumor cells
Natural Killer cells
Other names of natural killer cells
Large granular lymphocytes
3rd population lymphocytes
Null lymphocytes
Non-B & Non-T lymphocytes
These are cells produced after the first exposure that remain in the circulation and can recognize and respond to an antigen faster.
Memory B cells
These are sites on an antigen that are recognized and bound by a particular antibody
Epitopes
It refers to family of cells or organisms having constitution.
Clone
It refers to an antigen that is capable of eliciting an immune response.
Immunogen
What are the best immunogens?
Proteins
Degree of foreignness is inversely proportional to immunogenicity. True or False?
False
Ideal size of immunogen
> 10,000D
It is a glycoprotein secreted by plasma cells that binds to specific epitopes on antigenic substances.
Immunoglobulins
Immunoglobulins that are not antibodies are called
Paraproteins
Classification of immunoglobulins
- IgA ([alpha] heavy chain)
- IgD ([delta] heavy chain)
- IgE ([epsilon] heavy chain
- IgG ([gamma] heavy chain)
- IgM ([mu] heavy chain)
Most abundant antibody in blood
IgG
Most abundant antibody in the body
IgA
Least abundant antibody
IgE
It is the basic unit of an antibody structure.
Domain
Domain is composed of
Two identical light chains and two identical heavy chains
Light chain and heavy chain of an antibody is linked by
Cysteine residues by disulfide bonds
Antibody heavy chains
Alpha, gamma, delta, mu, or epsilon chains
Antibody light chains
Kappa or lambda chains
It holds both the light and heavy chains together
Disulfide bonds (cysteine residues)
It refers to the carboxyl (-COOH) terminal region of an antibody
Constant region
It refers to the amino (-NH2) terminal regions of both light and heavy chains of immunoglobulins
Variable region
Structure that provides the heavy chain a degree of flexibility enabling it to change its shape.
Hinge region
The portion of the Ig molecule from the carboxyl region to the hinge region.
Fc fragment
The portions of the Ig from the hinge region to the amino terminal.
FAB (antigen-binding fragments)
Enzyme that can cleave an antibody into 3 parts
Papain
Enzyme that can cleave an antibody into 2 parts
Pepsin
Location of cleavage by papain
Above hinge region
Location of cleavage by pepsin
Below hinge region
IMMUNOGLOBULIN VARIANTS
It is the dominant type found on the immunoglobulins of all normal persons.
Isotype
IMMUNOGLOBULIN VARIANTS
It is present primarily in the constant region and sometimes in variable region; not all variants occur in all members of a species.
Allotype
IMMUNOGLOBULIN VARIANTS
It is located in the variable part of the antibody associated with the hypervariable regions that form the antigen-combining site.
Idiotype
Only immunoglobulin subclasses that are capable of attachment to phagocytic receptors.
IgG1 and IgG3
Phagocytic cells with Fc receptors
Neutrophils
NK cells
Mature B cells
Most significant immunoglobulin in blood banking
IgG, IgM, and IgA
Form of IgG
Monomeric form
IgG reacts best at what temperature
37 degree Celsius
Important antibody in HDN
IgG
Abundant antibody secondary immune response
IgG
Major antibody in precipitation
IgG
IgG subclass that cannot cross placenta
IgG2
IgG subclass that cannot activate complement
IgG4
Most efficient IgG subclass in activating complement
IgG3
Most commonly encountered as naturally occurring antibodies in the ABO system.
IgM
IgM exists in
Both monomeric and polymeric forms
IgM reacts best at
22°C to 24°C
Most efficient isotype in activating complement
IgM
Secretory IgA is usually found in
Mucosal tissues of the body
Monomeric IgA is found in
Serum
It refers to the immune response induced by initial exposure to the antigen.
Primary Immune Response
First antibody produced in primary immune response
IgM
Predominant antibody in secondary immune response
IgG
Secondary Immune Response is also called
Anamnestic response
Antibodies found in the serum of individuals who have never been previously exposed to RBC antigens by transfusion, injection, or pregnancy
Naturally occurring antibodies
Most naturally occurring antibody
IgM
Naturally occurring antibodies are also called
Isoagglutinins
Antibodies found in the serum of individuals who have been transfused or pregnant.
Immune antibodies
Most immune RBC antibodies
IgG
Also called irregular or atypical antibodies
Unexpected antibodies
Produced after exposure to genetically different, or nonself, antigens such as different RBC antigens after transfusion
Alloantibodies
Antibodies produced in response to self-antigens.
Autoantibodies
It is the ability of a particular antibody to combine with a particular antigen.
Specificity
Reaction between similar epitopes
Specific reaction
Occurs when certain epitopes of one antigen are shared by another antigen and the same antibody can react with both antigens
Cross-reaction
It is produced when the antigen and antibody combine.
Immune complex
It is the strength of the binding between a single antibody and an epitope of an antigen.
Affinity
It is the overall strength of reaction between several epitopes and antibodies
Avidity
Refers to the number of epitopes per molecule of antigen
Valency
Location of red cell antigen
Surface of red blood cells
Location of red cell antibodies
Plasma or serum
Order of complement discovery
C1 2 3 4 5 6 7 8 9
Order of complement activation
C1 4 2 3 5 6 7 8 9
Complement pathway that is initiated by antigen-antibody complexes
Classical pathway
Complement pathway that is initiated by foreign cell-surface constituents
Alternative pathway
Function of membrane attack complex
Mediate cell lysis in the target cell
Disease due to defects in the immune system
Immunodeficiency
Inflammatory response to a foreign antigen
Hypersensitivity
Type I reaction:
Anaphylaxis or immediate hypersensitivity
Type II reaction:
Cytotoxic hypersensitivity
Type III reactions:
Immune complex hypersensitivity
Type IV reaction:
Delayed or Cell Mediated hypersensitivity
It results from a single clone of lymphoid-plasma cells producing elevated levels of a single class and type of immunoglobulin
Monoclonal Gammopathy
It is classified as a secondary disease and characterized by the elevation of two or more immunoglobulins
Polyclonal Gammopathy
Represents a breakdown of the immune system’s ability to discriminate between “self” and “nonself”.
Autoimmune Disease
Results when the maternal IS produces an antibody directed at an antigen present on fetal cells but absent from maternal cells.
Hemolytic Disease of the Newborn
Severe HDN is most often associated with what antibodies
IgG1
Detection of the A, B, and D antigens
Forward / Direct ABO & Rh typing
Detection of ABO antibodies
Reverse / Indirect ABO typing
The detection of preformed antibodies to red cell antigens as a result of previous exposure to red cells through transfusion and pregnancy
Antibody screen
Determination of the red cell antibody specificity after detection with the antibody screen.
Antibody identification
Serologic check of the donor unit and patient compatibility before transfusion
Crossmatch
Major crossmatching
Donor cells; Recipient serum
Minor crossmatching
Donor serum; Recipient cells
Produced from several different clones of B cells that secrete antibodies of different specificities
Polyclonal antibody-based products
Produced from single clones of B cells that secrete antibodies of the same specificity
Monoclonal antibody-based products
Hybrid cells formed by the fusion of myeloma cells and antibody-producing cells
Hybridomas
NK cells kills target using
Granzymes & perforins
NK cell kills target lacking
MHC restrictions
NK cells are identified thru
Flow cytometry
CD markers of NK cells
CD16 CD56
Cardinal signs of inflammation
Rubor - Redness Calor - Heat Dolor- Pain Tumor - Swelling Functio laesa- Loss of function
Hallmark of inflammation
Increased vascular permeability
First cell to arrive during inflammation
Neutrophils
Second cell to arrive during inflammation
Monocytes
Movement of leukocytes from center to periphery of blood
Migration
Transient adhesion of leukocytes to the endothelial cells
Rolling
Firm attachment of the leukocytes to the endothelial cells
Adhesion
Migration of leukocytes through the endothelium into the tissues
Transmigration / Diapedesis
Unidirectional or targeted movement of the leukocytes towards antigen/bacteria in response to certain chemical
Chemotaxis
Coating of the bacteria so that they are easily phagocytosed
Opsonization
Process by which bacteria are killed/eaten up by the white blood cells
Phagocytosis
Final stage of resolution and repair is associated with
Fibroblast proliferation
Fibroblast proliferation may result in:
Totally repaired
Formation of abscess with loss of function
Granuloma formation
Stage of phagocytosis
Initiation
Chemotaxis
Engulfment
Digestion
Phagocytosis is initiated as a result of
Tissue damage
Activated phagocyte has increased surface receptor for adherence of
Complement receptor 3
Laminin receptor
Lencyl, formyl, methionyl, phenylalanine
Cell motion without chemotaxis
Random
Example of chemotaxins
Complement 3a, 5a, IL-8
Fusion of phagosome and lysosome
Phagolysosome
Production of reactive oxygen species which are toxic to bacteria
Respiratory burst
Enzymes involved in respiratory burst
NADPH Oxidase
Catalase
Superoxide dismutase
Disorder associated with impaired NADPH Oxidase
Chronic Granulomatous Disease
Family of glycoproteins produced by all animal cells that exert a virus-nonspecific but host-specific antiviral activity
Interferon
Type I interferons include
IFN alpha
IFN beta
Type II interferon include
IFN gamma