Immunology Flashcards
What is a granuloma?
Collection of activated macrophages and lymphocytes
What does a granuloma activate?
T lymphocytes
Lung granuloma differential
Sarcoid
TB
Leprosy
Silicosis
Hypersensitivity pneumonitis
Foreign bodies
Presentation of antibody deficiencies
Recurrent bacterial infections
Antibody mediated autoimmune diseases
Primary antibody deficiency example (2)
CVID
IgA deficiency
What is CVID?
Low IgG, M, A
Recurrent bacterial infections -> associated with autoimmune disease
Are IgA deficiency people symptomatic?
only 1/3 are
Differential of recurrent bacterial infections and hypogammaglobulinaemia
Primary: antibody deficiency, CVID, IgA, etc
Secondary: protein loss: nephritic syndrome, failure of protein synthesis: CLL, myeloma, non-hodgkins
What are complement proteins?
Proteins secreted by the liver to act as a sticky coat for intruders in order to turbo-boost immediate immune defence
Complement deficiency predisposes to
Bacterial infection
IgGs are broken down by
Endothelial cells and recycled to have longer half life (NOT BROKEN DOWN BY LIVER!!!)
What are NK cells?
Kill cells that lack MHC
No long term memory
Can you give biologics to someone with liver cirrhosis ?
Yes, because not metabolized by the liver
Biologics are essentially the same as
Antibodies
NK cell defects predispose to
VZV, HSV, CMV, HPV
What immunity are NK cells apart of
Innate
Remove cancer cells
How does the innate recognition of invaders work?
They are Toll-Like-Receptors (TLRs)
Respond to PAMPS: pathogen associated molecular patterns
TLRs are expressed on
Phagocytes and dendrites
Outcome of TLR activation
Pro-inflammatory and type 1 interferon secretion
TLR dysfunction
Too little: immunodeficiency
Too much: autoimmunity
TNFa inhibitors block
Pro-inflammatory cytokines
TNFa is an
Immediate early fire alarm signal in response to many stressors
What cells activate TNFa
Macrophages
Neutrophils
Tcells
Endothelium
Mast cells
Biologic drugs are artificial
Antibodies
Biologic drugs act as passive/active immunization
Passive
How are biologics administered?
By injection every couple of weeks
4 types of transplant rejection
Hyperacute, acute cellular, acute vascular, chronic allograft
Hyperacute is within
Minutes to hours
T2 hypersensitivity, antibody and compliment fixation
Acute cellular rejection happens within
5-30 days
Type IV hypersensitivity, CD4 and 8 cells
Treat with immunosupression
Acute vascular rejection is within so long?
What type of hypersensitivity?
5-30 days
II hypersensitivity
De novo antibody and complement fixation
NEEDS LOTS OF IMMUNOSUPRESSION
Chronic allograft failure time
What is it due to?
> 30 days
Fibrosis, scarring
Vaccination produces memory in
B and T cells
What are created during primary immune responses?
Long-lived memory B cells
What reactivates in response to a second encounter with the antigen?
Memory B cells
Vaccination simulates
Rare naive T cells
–> become effector T cells which either
1. die due to apoptosis in absence of persisting antigen
2. memory T cells are maintained at low frequency
5 types of vaccines
Inactivated
Live
RNA
DNA
Viruses
Example of inactivated
Polio, Hep A, Hep B
HPV, Diphtheria, H influenza B, etc
5 in 1 vaccine includes
Innactivated
Polio
Pertussis
Diptheria
Tetanus
H inf B
Live vaccines
MMR vaccine
Chickenpox is
Live
DNA/RNA vaccines direct
Assembly of the antigenic protein inside the host cell
Example of DNA/RNA vaccines
COVID
Virus vaccines are
Empty shells (capsids) made from viruses that have no DNA/RNA
Examples of VLP vaccines
HPV and Hep B vaccines
