Lecture 8: Flashcards
(27 cards)
T cell development
From Bone marrow > migrating from blood > leave thymus by blood stream
- Thymocytes/T cells go to other organs (from the thymus)
Functions of NK cells
Natural killer cells
Kill various infected or transformed cells (pre-cancerous cells e.g. tumour cells)
Types of T cells
- T helper cells (Th) - these cells help B cells & control isotope switching
- T regulatory (suppressor) cells (T REG; Tregs)
- Cytotoxic T cells (Tc)
How can we identify T cell subpopualtions?
Using monoclonal antibody phenotypic markers
Summary of some monoclonal antibodies and their cell specificity
- E.g. CD2 cells against mouse reacts with T cells, thymocytes, NK cells in mice
- CD4 reacts with TH1 & TN2 cells and monocytes/macrophages
- CD8 reacts with TC cells
Therefore, TH cells could be described as CD4+ CD8-
Summary of some monoclonal antibodies and their cell specificity
Separation of cells using mabs
PANNING (like panning for gold)
- trying to separate different types of cells using monoclonal antibodies
- in this example uses immobilised monoclonal antibody CD4
- TH cells will bind to dish other non-reactive cells will not
- if want to get TH cells off, increase salt concentration slightly and they will dislodge
Further sub populations of TH cells
TH0, TH1, TH2, TH3, TH17
TH0 precursors for TH1 & TH2 etc
TH1 subset generate mainly IL-2 & IFNy & interact with macrophages. They:
- enhance antigen presentation
- enhance Fc receptor expression
…..
Further sub populations of TH cells
TH2 cells produce mainly IL-4, IL-5, & IL-10
- they promote IgE production & eosinophil generation
TH3 cells produce mainly IL-4, IL-10 & TGFβ
- they suppress immune response in mucosal areas & may induce immune tolerance
TH17 cells mainly produce IL-17
- amplify innate immune system
….
Overall
- TH1 cells are involved in TYPE 1 IMMUNITY mainly against extracellular bacteria & viruses
-TH2 cells are involved in TYPE 2 IMMUNITY against metazoan parasites
..
Allergies idea
Out of balance type 1 and type 2 leads to allergy state
Innate lymphoid cells
- group 1 ICLs (NK cells & ILC1s) both are cytotoxic.
- they produce type 1 cytokines (IFNƳ, TNF)
- …..
NK cell development
Part of innate immune system
………
NK cells - morphology
Not able to recognise
Innate lymphoid cells
- group 2 ICLs
- secrete Type 2 cytokines
……
Innate lymphoid cells
- group 3 ILCs (ILC3s etc)
- produce IL-17A and/or IL-22
- ICL3s assist in maintaining microbiota balance in GI tract
Disbiosis - ……
Cell types in mammalian immune system: MONONUCLEAR PHAGOCYTES (monocytes/macrophages)
Cell types in mammalian immune system: MONONUCLEAR PHAGOCYTES (monocytes/macrophages
Monoblast & promoncytes in bone marrow > monocyte in blood vessels> Matures into a macrophage in tissues
Cell types in mammalian immune system: MONONUCLEAR PHAGOCYTES (monocytes/macrophages
Monocyte morphology
Distribution of macrophages
- LUNG - alveolar macrophages
- in connective tissue histiocytes
- Osteoclasts in bone (if damage ur bone they remodel bone, ingest the damaged bone by releasing enzymes)
- kupffer cells in liver sinusoids (purple is nucleus, pink is cytoplasm) (e.g. dead red blood cell they pull them up and recirculate the material from it)
Distribution of macrophages
- spleen & lymph nodes - free & fixed macrophages
- bone marrow - sinusoidal ling cells, macrophages
- serious cavity - peritoneal macrophage
