Immunology Flashcards
Cells that are in the innate immune system
Mast cells, macrophages, NK cells, Neutrophils, Complement
With regards to immune deficiency, what does SPUR refer to?
S - serious infectionsP - Persistent infectionsU - Unusual infectionsR - Recurrent Infections
Features that may indicate a primary immune deficiency (6)
Weight loss/Failure to thriveSevere skin rashesChronic diarrhoeaMouth UlcerationUnusual Autoimmune DiseaseFamily History
The main difference between primary and secondary immune deficiencies is…
that primary only tends to involve one component of the immune system, secondary tends to involve multiple
Examples of Secondary Immune Deficiencies
HIV, Malignancy, nutrition disorder, infection, treatment interventions
Cells in the Innate Immune system (4)
MacrophagesNeutrophilsMast cellsNK cells
Phagocytes of the innate immune system (2)
Macrophagesneutrophils
Proteins of the innate immune system (3)
ComplementCytokinesAcute Phase Proteins
What does the innate immune system stimulate?
Rapid clearance of micro-organismsAcquired Immune response
What does the innate immune system recognise in infectious organisms?
PAMPs
Cells of Acquired Immune Response (2)
B LymphocytesT lymphocytes
Proteins of acquired immune response (1)
Antibodies
Which immune system is NOT genetically encoded?
Acquired
Functions of Phagocytes (5)
Initiation and amplification of inflammatory responseScavenging of cellular and infectious debrisIngest and kill micro-organismsResolution and repairProduce inflammatory molecules regulating immune system
TRUE OR FALSE - phagocytes are particularly important in the defence against viruses and bacteria
FALSE - they are important in the defence against bacteria and fungi
In phagocyte deficiencies it is not uncommon to see the following infections…
Common - staph. aureusUnusual - burkholderia cepaciaMycobacteriaFungi - candida, aspergillus
TRUE OR FALSE - phagocytes are important in reducing the numbers of infections as can be seen in stem cell transplant recipients
TRUE
Reticular Dysgenesis is characterised by an absence of _____ and other myeloid cells with almost complete deficiency of _______ in peripheral blood.
neutrophils, lymphocytes
In reticular dysgenesis, a lack of both innate and adaptive immune response is due to a failure of ______ ______ differentiating along a ______ lineage
stem cells, myeloid
Kostmann syndrome is a rare autosomal ______ disorder
recessive
Kostmann syndrome is a severe, chronic _____ where normal levels of ______ are >3000µL and in sufferers is <200µL
neutropenia, neutrophils
G-CSF is
granulocyte colony stimulating factor which assist the maturation of neutrophils
In a condition where issues arise in the ability to bind endothelial adhesion markers, you may see…
increased levels of neutrophils with recurrent bacterial and fungal infections.There can be deep infections with no pus formation
Why does a loss of function of a receptor or antigen recognition marker not cause severe disease?
there is usually other receptors or antigens which can be picked up
Example of a disease where there is failure of oxidative killing mechanisms
Chronic Granulomatous disease
consequences of chronic granulomatous disease
failure to degrade chemoattractants and antigens as well as disease –> accumulation of neutrophils, macrophages and lymphocytes
Test for chronic granulomatous disease?
Nitroblue tetrazolium test –> looking for release of H2O2
Describe the IL-12 –> IFNy network
infected macrophages produce IL-12IL-12 induces Th1 cells to secrete IFNyIFNy feeds back to macrophages and neutrophils Leads to production of TNF –> NADPH oxidaseOxidative pathways
Defects in IL-12:IFNy network may increase susceptibility to…
mycobacterial infections and IC bacteria
Where do T lymphocytes arise from?
haematopoetic stem cells
TRUE or FALSE - T lymphocytes defend against intracellular pathogens and bacteria
FALSE - against intracellular pathogens and viruses
The CD4+ T Lymphocyte has immunoregulatory functions - give some examples (3)
Provides co-stimulatory signals for CD8 and B lymphocytesProduces cytokinesRegulates other lymphocytes and phagocytes
The CD4+ lymphocyte recognises peptides present on HLA class __ molecules?
II - 2
CD8+ lymphocytes recognise peptides present on HLA class __ molecules?
I - 1
CD8+ lymphocytes are specialised killer cells…give examples (3)
Production of pore-forming molecules - perforintriggering of apoptosis of targetsecretion of cytokines i.e. IFNy
Where are mature B lymphocytes typically found? (3)
bone marrow, lymphoid tissue, spleen
When a B lymphocyte is activated, what happens?
Undergoes complex genetic rearrangement, forms memory cells and plasma cells
Function of antibodies (3)
Identification of pathogensRecruitment of other immune system components for pathogen removalNeutralisation of toxins
X-Linked SCID is involved with a mutation in which cytokine receptor?
IL-2
What is IL-2 involved in?
ability to respond to other cytokinesT cell and NK developmentproduction of B cells
Is it advisable to give vaccines to X-linked SCID patients?
No - there is a defect in acquired immune response so could actually produce more problems than solutions
DiGeorge patients suffer from immune deficiencies, which organ fails to develop sufficiently?
thymus
What level of B cells would you expect in a DiGeorge patient?
Normal or increased B cells
What sort of recurrent infections would you expect to see in B cell deficiencies?
Bacterial Resp. tract, GI
What does common variable Immune deficiency indicate?
low levels of IgG, IgA, IgE recurrent bacterial infectionsautoimmune diseases
T cells mature in the ______ gland
thymus
Which cells provide immunity to extracellular bacteria, fungi and parasites?
neutrophils, macrophages, complement system, antibodies, cytotoxic T cells, NK cells
Where are basophils and eosinophils found?
circulating the blood
Th2 cells contribute to which hypersensitivity reaction?
Type 1 Hypersensitivity
T helper cells recognise which MHC class
Class II
What is the lymphatic system?
a system of vessels draining fluid from body tissues with lymph nodes positioned regularly to trap pathogens
What are the kupffer cells?
macrophages in the liver
Most abundant immunoglobulin
IgG
Common antibodies involved in Type II hypersensitivity
IgG and IgM
B cells differentiate into _____ cells
plasma cells
Type III hypersensitivity reactions result in the accumulation of which cell types?
neutrophils, macrophages
What is the complement system?
a family of approx. 30 proteins produced in the liver and circulating the blood as inactive precursors
B cells mature in the ____ _____
bone marrow
What is an antigen?
any substance which can stimulate an adaptive immune response i.e. lipids, proteins, carbohydrates
where are monocytes found?
circulating the blood - move into peripheral tissues and differentiate into macrophages
CD4 cells differentiate into what upon activation?
Th1 and TH2 cells
What is the function of CRP?
Opsonisation
What are antibodies?
proteins that are produced in response to an antigen and bind specifically to that antigen
C3b activates the rest of the complement cascade which is…
C5 - C9
Ig which can cross the placenta?
IgG
What is the purpose of phagocytic cells?
they ingest and clear debris from the body including dead/dying apoptotic cells