What are the granulocytes?
Eosinophils, Basophils and Nuetrophils
What are the agranulocytes?
Lymphocytes and macrophages
How can you identify basophils?
Can’t see the nucleus due to dark-purple staining granules
How can you identify neutrophils?
Multi-lobes nucleus, stain light purple
How can you identify Eosinophils?
Stain RED!! Bi-lobed nucleus
How can you identify Lymphocytes?
Small (same size as RBC’s)
How can you identify Monocytes
BIG!! Kidney bean shaped nucleus
What are the antigen-presenting cells?
Dendritic cells, macrophages and B Lymphocytes.
Where is Major Histocompatibility Complex Class-I found and what does it present to?
It is present on all nucleated cells and presents to CD8+ cytotoxic T cells.
Where is Major Histocompatibility Complex Class-II found and what does it present to?
Class II is restricted to dendritic cells, macrophages, B cells etc. i.e. APCs. Class II presents only to CD4 T Lymphocytes.
What is the function of Basophils?
- Prevent Blood Clotting - By releasing Heparin.
- Mediating allergic reactions: Basophils release histamine during allergic reactions. Basophils are also thought to play a role in causing the body to produce the antibody called immunoglobulin E (IgE).
What is the function of Neutrophils?
They destroy pathogens by phagocytosis and release of hydrolytic enzymes.
What is the function of Eosinophils?
Their primary function is to combat parasitic infection.
What is the function of B Lymphocytes?
B Lymphocytes are the mediators of humoral immunity. B cells produce antibodies that serve as receptors that recognise antigens and initiate a process of activation of the cells.
What is the function of Cytotoxic T Lymphocytes (CD8+)?
Cytotoxic T lymphocytes kill cells harbouring intracellular microbes.
What is the function of T Helper Lymphocytes (CD4+)?
When T helper cells are activated, they produce cytokines which promote activation of macrophages, inflammation proliferation and differentiation of T and B Lymphocytes. They are activated by MHC Class II
What do Lymph nodes do?
- The Lymph nodes collect antigens from the periphery to present to naive T lymphocytes to activate the adaptive immune system.
- APCs (dendritic cells) will always travel to the nearest lymph node for presentation. Therefore antigens arrive via different routes to different lymphoid tissue.
What are the 5 types of antibodies?
IgA, IgD, IgGE IgG, IgM
Where is IgA found and what does it do?
- Found in saliva, tears, mucus, breast milk and intestinal fluid.
- IgA protects against ingested and inhaled pathogens.
Where is IgD found and what does it do?
- IgD is found on the surface of your B cells.
- Though its exact function is unclear, experts think that IgD supports B cell maturation and activation.
Where is IgE found and what does it do?
- IgE is found mainly in the skin, lungs and mucous membranes.
- IgE antibodies cause your mast cells (a type of white blood cell) to release histamine and other chemicals into your bloodstream. IgE antibodies help fight off allergic reactions.
Where is IgG found and what does it do?
- This is the most common antibody, making up approximately 70% to 75% of all immunoglobulins in your body. It’s found mainly in blood and tissue fluids.
- IgG antibodies help protect your body from viral and bacterial infections.
Where is IgM found and what does it do?
- IgM is found in your blood and lymph system.
- IgM antibodies act as the first line of defence against infections. They also play a large role in immune regulation.
What are Pathogen-Associated Molecular Patterns (PAMPs)?
- Pathogens have molecules that humans don’t have and they’re called pathogen-associated molecular patterns or PAMPs.
- PAMPs are recognized by Pattern Recognition Receptors or PRRs which are receptors on various immune cells including macrophages, neutrophils, eosinophils, basophils and mast cells.
