Fundamentals of Immunology (P) Flashcards
What is immunology?
It is the study of the immune system
What is the meaning of IS?
Immune system
What is the IS?
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
What are the fxns of the IS?
1) To recognize self from non-self
2) To defend the body against the non-self
What is immunity?
1) It refers to the process by w/c a host organism protects itself from attacks by external and internal organs
2) It is defined as resistance to disease, specifically, an infectious disease
What are the 2 major arms of the IS?
1) Innate immunity
2) Acquired immunity
What is the other term for innate immunity?
Natural immunity
What is the other term for acquired immunity?
Adaptive immunity
What is the fxn of innate and acquired immunity?
They work to prevent infection and damage cells from destroying the host
What are the characteristics of innate immunity?
1) It is present at birth
2) It is non-specific
3) It is considered as the 1st line of defense
Innate immunity is comprised of what?
1) Physical and biochemical barriers
2) Numerous cells (ex. neutrophils)
What is the mechanism of nonspecific characteristic of innate immunity?
It is the same response that is used upon repeated exposure to the same organism/s
What is the other term for acquired immunity?
Adaptive immunity
What are the characteristics of acquired immunity?
1) It is specific
2) It expresses immunologic memory
3) It is considered as the 2nd line of defense
What are the components of acquired immunity?
1) Lymphocytes (cellular component)
2) Abs (humoral component)
What is the mechanism of acquired immunity being specific?
It allows the body to recognize, remember and respond to a sp Ag
What is the mechanism of immunologic memory being expressed by acquired immunity?
It allows the organism to respond more effectively if reinfection w/ the same microorganism occurs
What are the 2 branches of acquired immunity?
1) Cell-mediated immunity
2) Humoral mediated immunity
What is the mechanism of HMI?
Antibody Mediated
What is the cell type present in HMI?
B cells
What is the mode of action of HMI?
Abs in serum
What is the purpose of HMI?
Primary defense against bacterial infection
What is the mechanism of CMI?
Cell mediated
What is the cell type in CMI?
T cells
What is the mode of action of CMI?
Direct cell-to-cell contact or soluble products secreted by cells
What is the purpose of CMI?
Defense against viral and fungal infections, intracellular organisms, tumor Ags, and graft rejection
What IS cells mediate cellular immunity?
1) Macrophages
2) T cells
3) Dendritic cells
What is the characteristic of cellular immunity?
It may be innate or adaptive
What are the fluid parts of IS that comprises humoral immunity?
1) Abs
2) Complement proteins
The fluid parts of IS are found where?
These are found in plasma, saliva, and other secretions
What is the characteristic of humoral immunity?
It may be innate or adaptive
Immunoglobulin is also called as what?
Antibody
What is antibody?
It is a complex protein produced by plasma cells, w/ specificity to Ags (or immunogens), that stimulate their production
What is the mechanism of action of Abs?
They act in response to sp foreign, non-self proteins, or other complex molecules not tolerated by the host
Abs are part of what type of immunity?
They are part of the HMI
What are the 5 classifications of Abs?
1) IgG
2) IgM
3) IgA
4) IgD
5) IgE
Out of 5 classifications of Igs, what Igs are the most impt in the blood bank section?
1) IgG
2) IgM
Answer the ff questions for the given Ab:
1) What is the MW of the given Ab?
2) What is the sedimentation coefficient of the given Ab?
3) What is the % of the given Ab in the total Ig present in the serum?
4) What is the classification of the given Ab?
5) Can the given Ab do complement fixation?
6) Can the given Ab cross the placenta?
Given Ab: IgG
1) 150,000 (smallest)
2) 7s
3) 70 - 75
4) Monomer (secondary immune response)
5) Yes
6) Yes
Answer the ff questions for the given Ab:
1) What is the MW of the given Ab?
2) What is the sedimentation coefficient of the given Ab?
3) What is the % of the given Ab in the total Ig present in the serum?
4) What is the classification of the given Ab?
5) Can the given Ab do complement fixation?
6) Can the given Ab cross the placenta?
Given Ab: IgM
1) 900,000 (largest)
2) 19s
3) 10
4) Pentamer (primary immune response)
5) Yes
6) No
Answer the ff questions for the given Ab:
1) What is the MW of the given Ab?
2) What is the sedimentation coefficient of the given Ab?
3) What is the % of the given Ab in the total Ig present in the serum?
4) What is the classification of the given Ab?
5) Can the given Ab do complement fixation?
6) Can the given Ab cross the placenta?
Given Ab: IgA
1) 160,000
2) 7s
3) 10 - 15
4) Dimer (secretory IgA) or monomer (serum IgA)
5) No
6) No
Answer the ff questions for the given Ab:
1) What is the MW of the given Ab?
2) What is the sedimentation coefficient of the given Ab?
3) What is the % of the given Ab in the total Ig present in the serum?
4) What is the classification of the given Ab?
5) Can the given Ab do complement fixation?
6) Can the given Ab cross the placenta?
Given Ab: IgD
1) 180,000
2) 7s
3) <1
4) Monomer (surface Ig)
5) No
6) No
Answer the ff questions for the given Ab:
1) What is the MW of the given Ab?
2) What is the sedimentation coefficient of the given Ab?
3) What is the % of the given Ab in the total Ig present in the serum?
4) What is the classification of the given Ab?
5) Can the given Ab do complement fixation?
6) Can the given Ab cross the placenta?
Given Ab: IgE
1) 190,000
2) 8s
3) 0.002
4) Monomer (parasitic infections)
5) No
6) No
What is the order of Abs in terms of volume / amt in % in the total Igs present in the serum?
G -> A -> M -> D -> E
What are the Abs that are monomer?
1) IgD
2) IgE
3) IgG
What is the Ab that is a dimer?
IgA
What is the Ab that is a pentamer?
IgM
Bet IgG and IgM, what Ab is the most impt in BB?
IgM
What Ig is considered as the most clinically significant Abs in BB?
IgG
IgG is commonly referred to as what?
Immune Abs
Why are IgG clinically significant?
Because these Igs react at 37 DC (body temp)
What is the fxn of IgG?
They are capable of destroying transfused Ag-(+) RBCs
The fxn executed by IgG causes what conditions?
1) Anemia
2) Transfusion rxns of various severities
Provide an ex of the result brought by the fxn of IgG
Hemolytic Disease of the Fetus and Newborn (HDFN)
What is the characteristic of IgG?
These Abs can cross the placenta w/c occurs during HDFN
What are the blood grp systems w/ clinically significant Abs (reactive at 37 DC)?
1) Rh blood grp
2) Kell blood grp
3) Duffy blood grp
4) Kidd blood grp
5) Lutheran blood grp
6) S blood grp
IgM are considered as what?
Naturally occurring Abs
What are the characteristics of IgM?
1) They are the most commonly encountered Abs in BB (ex. ABO blood grp Abs)
2) They are most commonly encountered as naturally occurring Abs in the ABO system
3) They are believed to be produced in response to commonly occurring Ags
4) They usually react best at ambient room temp
What are the exs of commonly occurring Ags where its presence stimulates IgM to occur?
1) Intestinal flora
2) Pollen grains
What are the other blood grps that may also produce IgM Abs other than ABO blood grp?
1) Lewis
2) Ii
3) P
4) MNS
What is the ambient room temp where IgM usually react optimally?
22 - 24 DC
What is the primary testing problem that is encountered w/ IgM?
IgM can interfere w/ the detection of clinically significant IgG
How can IgM interfere w/ the detection of clinically significant IgG?
By masking the reactivity of IgG
What is the characteristic of IgM?
They cannot cross the placenta
What are the blood grp systems w/ naturally occurring Abs?
1) ABO blood grp
2) Lewis blood grp
3) P blood grp
4) MN blood grp
What are the 2 classifications of Abs in BB?
1) Naturally occurring
2) Immune Abs
What are the Abs that are present under naturally occurring Abs?
1) ABO Abs
2) Lewis Abs
3) P blood grp Abs
4) Anti-M and Anti-N
What are the Abs present under immune Abs?
1) Rh Abs
2) Kell Abs
3) Kidd Abs
4) Lutheran Abs
5) Duffy Abs
6) Ss Abs
What is the other term for Ab rgnts?
Antisera
What is the fxn of antisera?
These are frequently used in the lab to detect blood grp Ags
Antisera can be either what?
Polyclonal or monoclonal
Bet polyclonal and monoclonal, what is more commonly used?
Monoclonal
What are the exs of antisera?
1) Anti-A
2) Anti-B
3) Anti-AB
4) Anti-D
Blood grp Abs are detected via what procedure?
Reverse blood typing / reverse grouping / serum typing
What are polyclonal Abs?
These are produced in response to a single Ag w/ more than 1 epitope
What is the characteristic of polyclonal Abs?
They are usually produced in vivo
What comprises an Ag?
It consists of numerous epitopes
What is the action of the epitopes present in an Ag?
It is the epitopes, not the entire Ag that a B cell is stimulated to produce Ab against
Therefore, these different epitopes on a single Ag induce the proliferation of a variety of B cell clones, resulting in a heterogenous population of serum Abs
True or False
Naturally occurring and immune Abs are both produced in rxn to encountered Ags
True
What are the characteristics of naturally occurring Abs?
1) These are Abs of IgM class
2) They usually react at room temp (22 - 24 DC)
3) They are found in the serum of individuals who have never been previously exposed to RBC Ags by transfusion, injection, or pregnancy
4) These Abs are probably produced in response to substances in the environment that resemble RBC Ags such as pollen grains and bacterial membranes
5) In BB, these commonly react w/ Ags of the ABH, Hh, Ii, Lewis, MN, and P blood grp systems
What test can be used to detect naturally occurring Abs?
Direct Coombs’ Test (DAT)
What are the characteristics of immune Abs?
1) These Abs are of the IgG class
2) They usually react at 37 DC (body temp)
3) These Abs are produced upon exposure to blood grp Ags not present in an individual (ex. Rh (-) pt transfused w/ Rh (+) blood)
Why are immune Abs considered as clinically significant?
Because when these Abs react w/ their respective Ags, it can cause hemolysis, thus leading to anemia (ex. HDFN)
What is the test used to detect immune Abs?
Indirect Coombs’ Test (IAT)
What is being utilized by IAT?
Anti-human globulin (AHG) rgnt
Abs can be either what?
Alloreactive or autoreactive
How are alloAbs produced?
These are produced after exposure to genetically diff, or nonself Ags such as diff RBC Ags after transfusion
When do alloAbs occur in the human body?
These occurs when a pt is transfused w/ blood components that contains Ags not present on the pt’s blood
Ex. An Rh (-) mother transfused w/ an Rh (+) PRBC, thus the mother will produce Anti-D in her serum
What is a potentially serious problem for blood bankers in connection to alloAbs?
Transfused pts who have alloAbs that are no longer detectable in the pt’s plasma or serum
If these individuals are transfused w/ the immunizing Ag again, they will make a stronger immune response against those RBC Ags, w/c can cause severe and possibly fatal transfusion rxns
Why are autoAbs produced?
These are produced in response to self-Ags
What are the characteristics of autoAbs?
1) These can cause rxns in the recipient if they have a specificity that is common to the transfused blood
2) These can react at a wide range of temps
3) Cold and warm autoAbs may occur in a single individual
4) These are implicated in autoimmune hemolytic anemia (AIHA)
How are monoclonal Abs produced?
These are produced in vitro via the utilization of hybridoma technology
What Abs are preferred in testing?
Monoclonal Abs
Why are monoclonal Abs preferred in testing?
Because they are:
1) Highly sp
2) Well characterized
3) Uniformly reactive
What are the Abs that are mostly used today in most rgnts?
Most rgnts used today are monoclonal in nature or are a blend of monoclonal antisera
