IMMUNOLOGY Flashcards
What is a granuloma?
- collection of MACROPHAGES and LYMPHOCYTES
How does a granuloma come about?
- non-specific inflammatory response triggered by antigenic agents
- activates T-lymphocytes and macrophages
- —-failure of REMOVAL of stimulus==> OVER PRODN of activated cytokines
- —> results in organised collection of persistently activated cells
DDX. of lung granuloma?
- SARCOIDOSIS
- mycobacterial disease (TB/leprosy)
- berylliosis, silicosis and other dust diseases
- chronic stage of hypersensitivity
- Foreign bodies
How do antibody deficiencies present as?
- RECURRENT BACTERIAL INFECTIONS:
- recurrent UPPER and LOWER respiratory tract infections
- RECURRENT GI infections
- common organisms
- viral: less common but still - Ab mediated autoimmune diseases (AHA/ ITP)
Which Ab is often deficient?
IgA
—–“Selective IgA deficiency”; 2/3s are asymptomatic—-1/3 with recurrent respiratory tract infection
Iary causes of hypogammaglobinaemia?
- Common Variable Immune Deficiency
- Specific Ab def.
- bruton’s agammaglobinaemia (NO B cells)
IIary causes of hypogammaglobinaemia?
- protein loss (enteropathy OR nephrotic syndrome)
- Failure of protein synthesis
- —CLL
- –MYELOMA
- –NHL
Which organ in our body is responsible for complement production?
- LIver produces these proteins to ACT as a sticky coat for intruders in order to turbo-boost immediate immune defense
What are the properties of NK cells?
- don’t need antigen specificity
- NO long-term memory
- fxn: Kills cells that LACK MHC molecules of the surface
What occurs with NK cell defects?
- recurrent VZV, HSV, CMV, HPV,
What specific pathological cell, does the NK cell also eliminate?
Cancer cells
What acts as our bodies’ own BUILT-IN BURGLAR alarm for microbes?
TLR’s expressed on phagocytes and dendrites
“toll-like receptors”
What occurs with ACTIVATION of TLR?
- pro-inflammatory cytokines and type 1 interferon secretion
What occurs with TLR dysfxn?
- leads to IMMUNODEFICIENCY or AUTOIMMUNITY
What occurs with TLR activators?
- used to BOOST immunity
- —seen in anti-skin cancer creams—-IMIQUIMOD
What occurs in HYPERACUTE REJECTION of a transplant?
- thrombosis and NECROSIS
- Typer II hypersensitivity
—-occurs within MINs to hours
Any rx for hyperacute organ rejection>
NO
How to treat acute cellular rejection?
Immunosuppression
Which transplant rejections types occur within 1 month?
- Acute CELLULAR rejection
2. Acute Vascular rejection
How does the chronic allograft failure occur?
- by immune and non-immune mechanisms
- FIBROSIS and SCARRING occurs
What occurs with pathologically with acute vascular failure?
by De novo Ab-complement fixation
—-causing VASCULITIS and TYPE II hypersensitivity
What occurs pathologically with acute cellular failure?
- CD4 and CD8 T-cells activation ….results in cellular infiltration and type IV hypersensitivity
Pros of inactivated vaccines
- made quickly
- elicit GOOD antibody responses
- easy to store (NO FRIDGE needed)
- safe
Disadvantages of inactivated vaccines
NOT VERY potent
- –doesn’t stimulate clonal expansion of Band T cells (so requires multiple vaccinations)
- Ab titres DIMINISH over time; so given BOOSTER shots
- —many killed organisms don’t stimulate good immune response
Name fractional, toxoid vaccines.
Tetanus
Diphtheria
Name fractional, subunit vaccines.
- Hep B
- Influenza
- Acellular pertussis
- HPV
- Anthrax
What kinda vaccine is H. Influenza type B?
fractional vaccines
– pure polysaccharide vaccines
When are whole organisms used for vaccines?
- polio
- Hep A
- Rabies
- Cholera
- Plague
- Pertussis
Examples of LIVE attentuated vaccines for viruses.
- VIRUSES: MMR/ Chickenpox/ yellow fever/ rotavirus/ smallpox/ polio
Name live attentuated vaccines for bacteria.
BCG
Oral typhoid
