Lecture 10: Innate cells Flashcards
What are autoimmune diseases
Immune system starts attacking your own body
What are hypersensitivity diseases?
Allergies and asthma
What is the hygiene hypothesis?
We are so clean today we aren’t expose to enough irritants
Name all the cells of the innate immune system (9)
- macrophage
- dendritic cell
- mast cell
- natural killer cells
- complement protein
- granulocytes
- neutrophils
- eosinophil
- basophil
List all of the cells of the adaptive immune system (6)
- B cell
- T cell
- Antibodies
- CD4+ T cell
- CDB+ T cell
- natural killer T cell
Which cell do both adaptive and innate share
Natural killer T cell
Where do all the cells come from?
Pluripotent hematopoietic stem cell
Where do pluripotent hematopoietic stem cells come from?
Bone marrow
How are more stem cells made?
They’re self renewing
What do stem cells respond to?
Colony stimulating factors and cytokines
What are colony stimulating factors
Proteins that bind to receptors on stem cells and tell them to differentiate
What is differentiation mediated by
Transcription factors
What is the rate of hematopoiesis for a normal body and an infected body?
Normal steady rate then can increase 10-20 fold
Do pluripotent stem cells directly differentiate or do they have intermediate types?
They have intermediate types and pass through different stages of differentiation
Can cells at each stage give rise to any cell?
No, they can give rise to multiple cells but not all cells
What are common progenitor cells?
The intermediate stages between a stem cell and an immune cell
How do transcription factors and cytokines and colony stimulating factors create cell differentiation?
- moving between different stages is due to cytokines and CSF
- this causes changes in transcription factor activity
- this transcription factor activity induces developmental changes in cell differentiation
What are monocytes/macrophages
A monocyte differentiates into a macrophage once entering tissue
Where are monocytes before they become macrophages?
Blood
What do macrophages do?
- detect pathogens via PRR or TLRs
- phagocytosis
- present pathogens to T cells (APC)
- activate adaptive immune system
- shape adaptive immune response via cytokines
- inflammation
What is phagocytosis
Capturing and killing pathogens, eating
What are antigen presenting cells?
Cells that present antigens to the adaptive immune system
What changes do a monocyte go through to become a macrophage?
- enlargen
- increase organelles
- increase phagocytic ability
- increased hydrolytic enzymes
How do macrophages increase inflammation
- isolate pathogen
- secrete cytokines
- raise body temperature
- recruit additional cells
What are the 1st class of phagocytes
macrophages
What are the 2nd class of phagocytes
dendritic cells
What are dendritic cells
Unusually shaped phagocytic cells
What do dendritic cells express high levels of?
MHCII
What is MHCII
Cell surface molecule required to present antigens to CD4+ T cells
Are dendritic cells antigen presenting cells?
Yes
What are dendritic cells the single most important for
Activation of naive T-cells
Is there just one kind of dendritic cell?
No, many subsets
What are the two different flavours of dendritic cells?
- non-lymphoid dendritic cells
- lymphoid dendritic cells
What are non-lymphoid dendritic cells called in skin and other organs respectively?
- Langerhans cells
- Interstitial dendritic cells
