Immunology Flashcards
(25 cards)
How may neutrophils kill bacteria?
Degranulation, reactive oxygen species, phagocytosis, NETosis
Describe positive feedback in neutrophils.
Cytokines
What two conditions may excess neutrophil degranulation cause?
Abscess, sepsis
What component of immune cells is vital for recognising pathogens?
PRRs - Pattern recognition receptors
Which non-specific pathogen component is recognisable by immune cells?
PAMPs - pathogen associated molecular pattern
What are macrophages? Which key immune components do they play a role in creating?
Phagocytes. TNF alpha (pro-inflammatory, mast cells), MHC class II
What is MHC?
Major histocompatability complex - activates other (specific) immune cells
How can degranulation of mast cells prevent further inflammation?
Releases TNL - an anti-inflammatory chemical
Name the main natural/physical barriers.
Skin, cilia, mucus
Which specific bacterial component can activate the complement system?
Mannose (and mannose binding lectin)
Describe the two major complement system reactions.
C3 -> C3a + C3b. C3b converts C5 -> C5a + C5b
What is the purpose of the complement system protein, C5b?
Creates the MAC (membrane attack complex), which kills pathogens by osmolality. Also activates mast cells
Where do the lymphocytes originate from?
Primary lymphoid tissues -> B in bone marrow, T in thymus
Describe how lymphocytes migrate from the primary lymphoid tissues.
Transendothelial migration to high endothelial venules
Which three immune components are required to activate B lymphocytes?
Helper Ts, PAMPs, antigens
Describe the first antibody produced and its main purposes.
IgM -> virus neutralisation and agglutination
After IgM is stopped in production, which antibodies are then produced?
IgG, IgA, IgD, IgE
Describe what waning of IgG and sIgA may cause in the foetus/newborn.
Transient hypogammaglobulinaemia
Apart from virus neutralisation and agglutination, what are the other functions of IgG and IgM?
Opsonisation, classical activation of the complement system
What are the two main types of T cell?
CD4+ (helpers), CD8+ (cytotoxic)
Which chemical causes proliferation of undifferentiated T cells?
IL-2 (interleukin 2)
Describe the differentiation of CD4+ cells.
IL2 -> TH0 -> Tfh + TH1
What are the purposes of Tfh and TH1 cells?
Tfh activate B lymphocytes, TH1 releases cytokines
What do natural killer cells do?
Initiate apoptosis
