Defence Cells Flashcards
What is microbial dysbiosis?
Caused by dental plaque build up
What are some examples of innate immune cells?
Monocytes/macrophages, mast cells, neutrophils, eosinophils and basophils
What are thrombocytes responsible for?
Clotting of blood
What are mast cells?
Granulocytes
Early responders to infection or tissue damage
protect against pathogens
role in allergy
What is the function of monocytes and macrophages?
Circulate in blood- monocytes
Migrate into tissues and differentiate into macrophages
early responders to infection or tissue damage
Phagocytose and present antigen
What are neutrophils?
Phagocytic granulocytes
most numerous
move to tissue when required
contain numerous granules
They produce NETS, extracellular structure to capture microbes
What’s the function of basophils and eosinophils?
Granulocytes
Less abundant
Degradative enzymes and antimicrobials
Both contribute to allergy
What do eosinophils play a major role in defence against?
Parasites, as larger than neutrophils
What do all defence cells derive from?
Precursor in bone marrow
What can defence cells differentiate into?
Myeloid or lymphoid
What are examples of innate and adaptive like immunity cells?
Dendritic cells, natural killer cells and innate lymphoid cells
What are dendritic cells?
Antigen Presentation
Derived from myeloid and lymphoid lineage
Activate B and T cells
What is an example of a dendritic cell?
Langerhan Cell
What is one of the main roles of dendritic cells?
Memory generation
What is a natural killer cell? (NK cells)
Large cells with granules
Recognise and kill abnormal cells/tumours/viral infected cells
Important role in holding back virus infections until adaptive immunity kicks in
What’s the function of innate lymphoid cells?
Link innate and adaptive immune immunity
What is examples of adaptive immune cells?
T cells and B cells
Where do T cells Mature?
Thymus
What is the function of T cells?
Give rise to cellular immunity
Directing antibody production
Recognise antigens through the receptors of t cell receptor
What are the different types of T cells?
T helper cells CD4+ ( help and support other immune cells)
Cytotoxic T cells CD8+( destroy our own cells which have become infected)
Regulatory T cells -Tregs- ( regulate or suppress other cells in immune system )
Naïve T cell, can differentiate into other T cells
What are the three signals for the CD4+ T Cell?
1’ MHC-TCR interaction
2’ co-stimulatory molecules interactions (CD80/CD86 and CD40 on DC —- CD40L and CD28 on T cell)
3’ signal dictates what T helper cell the naïve cell becomes.
Function of CD4+ T cells? (subsets)
TH1 cells support macrophages to destroy intracellular microbes
TH2 cells produce cytokines which recruit and activate mast cells, eosinophils and promote barrier immunity at mucosal surfaces
TH17 cells secrete IL-17 family cytokines that induce local non-professional immune cells to release cytokines and chemokines
TFH cells induce specific B cell responses (promote opsonising antibody response)
Treg cells suppress T cell activity to prevent autoimmunity
Function Of B cells
-Communicate with T cells
-Have a specific B cell receptor for antigens
-B cells produce antibodies
-Plasma cells are great big antibody factories
-Memory B cells are important to mount a quicker antibody response to any subsequent infections
