immune system Flashcards
The function of the immune system is to…
- prevent infections
- eradicate established infections
- detect and eliminate tumours as well as tolerate self
Congenital (primary) immune deficiencies
e.g. patients who completely lack key cells and molecules of the immune system
Acquired (secondary) immune deficiencies
e.g. HIV infection that leads to the eradication of key immune cells
The immune system is integrated with other systems…
gastrointestinal, cardiovascular, respiratory, nervous, endocrine, skin
Molecules of the immune system can act in a … matter
Autocrine
paracrine, or
endocrine (when secreted)
The cells and molecules of the immune system access most organ systems in the body by travelling via:
blood vessels
lymphatic vessels
Immune cells originate from…
bone marrow stem cells
central sites
often used to refer to lymphoid tissues or lymphoid organs
Primary lymphoid organs:
bone marrow, thymus
Secondary lymphoid organs:
spleen, lymph nodes, mucosal & cutaneous associated lymphoid tissues
Peripheral sites
all other tissues and systems
skin, liver, gut, heart, brain, CNS, muscle, lungs etc
Innate
Neutrophil
Basophil
Eosinophil
Monocyte
Adaptive
Lymphocyte
Hallmarks of the Innate Immune System
Speed - Early, rapid
Duration - short-lived
Repetitive - responds the same way each time a microbe is encountered
Interactive - with other cells of the innate immune system and with cells of the adaptive immune system
Non-reactive to the host
Lymphocytes
express receptors that specifically recognise a wider variety of molecules produced by microbes as well as noninfectious substances
lymphocytes expand and differentiate into…
Effector cells
Memory cells
how does innate immune system tell the difference between self and non-self?
Different Microbes express different “patterns”
Our own cells do not express these microbial patterns
Epithelial, Endothelial and Resident Immune Cells express receptors on their surface that allow them to sense danger
Phagocytes
neutrophils & macrophages
scavengers that ingest microbes