Immunology Flashcards
Outline some non-specific pathogenic defences
Physical = skin, flow of fluid (e.g parotid)
Chemical = stomach acid
Inflammation
Compliment cascade
What happens during inflammation at microscopic level?
- vasodilation of blood vessels in area
- increased permeability of blood network to allow emigrate of WBCs into site
- chemotaxis (migration of white blood cells up a conc. gradient)
Name the 5 cardinal signs of inflammation
- Calor (heat)
- Rubor (Redness)
- Tumor (swelling)
- Dolor (Pain)
- Functio laesi (loss of function)
What do leukocytes do in inflammation
- secrete reactive substances (peroxide, oxygen radicals) to denature the pathogens
- phagocytes will engulf pathogenic/foreign material
- can become antigen presenting to trigger specific immune system
What is the compliment cascade?
A process used to compliment and enhance abilities of antibodies and phagocytic cells to ramp up inflammation
Made up by a cascade of small proteins in the liver
What are the effects of the compliment cascade?
activated compliment factors
- cell lysis
- inflammatory trigger
- opsonisation (covering a bacteria to label it for phagocytosis)
What is hereditary angiodema and how can you manage it?
disease causing recurrent episodes/attacks of severe swelling as the ‘check’ for C1 (classical pathway) is gone, so compliment cascade is activated uncontrollably
Management = give C1 esterase inhibitor
Define antigenic
Anything that has the capability to initiate a specific immune response
Different functions of antibodies
- mark an antigen to attract other cells
- blocking the action of the antigen
Define humoral immunity
aspect of immunity concerning production of antibodies by B lymphocytes (B cells)
antigens bind to B cells, which triggers B cell proliferation and production of antibodies
Describe the differences between Humoral immunity and cell-mediated immunity
Humoral = B cells, producing antibodies
Cell-Mediated = T cells, killing pathogens
What is cell-mediated immunity good at targeting?
More complex cellular structures than just antigens
- non-self cells
- tumour cells
- cells infected by viruses and as such as giving off abnormal antigens
outline cell-mediated immunity
T-cell receptor binds to an antigen, causes T-cell clonal expansion, activated cytotoxic T cells released cytotoxic chemicals, cytokines
How does adaptive immune memory work?
After exposure, specific lymphocytes with differentiate into memory cells, so on second exposure produces an exaggerated immune response
What is tetanus?
Infection from Clostridium Tetani bacteria, toxin causes uncontrolled muscle spasm, can lead to respiratory failure, trismus
Describe the difference between active and passive immunity
Active immunity = when our own body protects itself from a pathogen (this includes vaccinations as you build the response to the modified pathogenic material)
Passive immunity = protection from a pathogen from an outside source (ex. in tetanus, giving antibodies for the produced toxin straight into pt, that protects you but no immune system engagement)
What is MHC?
Major Histocompatibility complex
cell to cell interactions to allow immune system to identify self-from non-self
Describe actions of Graft vs Host disease in leukaemia
- chemo/radio is used to kill all blood cells and haematopoietic stem cells
- transplant of immunocompetent stem cell into bone marrow
- instead of host attacking transplanted cells, the ‘new immune system’ attacks the host cells
Oral signs of Graft vs Host disease
White patches in the mouth, that look like lichen planus, dry mouth, dry eyes, jaundice
