https://padlet.com/2039832/idwivveoxtj3zzqe Made with panache en-us 2021-11-23 07:10:34 UTC 2021-11-23 08:52:08 UTC hello@padlet.com 2039832 https://padlet.com/2039832/idwivveoxtj3zzqe/wish/1907763919 What we know?

1. There are 3 pathways of complement activations, alternative, lectin, classical pathway. 
2. The key components in all 3 pathways are different, however, the end product may be C3 convertases. 
3. Opsonisation is also known as "Tagging"

Want to know?

1.  What triggers the activation of pathways?
2.  Where do the enzymes (convertases) produced?
3.  What are the final effects on the host?

What we learned?

1.  C3b and C5b convertases are the final product that induces 4 results of complement activation.
2.  C3b - opsonisation and endocytosis of bacterium by macrophages.
3.  C3b - phagocytosis of immune complex in spleen and liver.
4.  C5b-9 - MAC adheres to the infected cell membrane, causing osmotic swelling and lysis.
5.  C3a & C5a- phagocytes migrate to the infection site and cause inflammation.

]]> 2021-11-23 07:11:23 UTC https://padlet.com/2039832/idwivveoxtj3zzqe/wish/1907763919 2039832 https://padlet.com/2039832/idwivveoxtj3zzqe/wish/1907768795 What we know?

1.  B cells are responsible in order to produce antibodies that will bind with antigen.
2.  There are 5 types of antibodies which are IgA, IgE, IgG, IgD, and IgM.
3.  B cells also function as antigen-presenting cells.
4.  There are 2 types of activation of B cells which are T cell-independent and T cell-dependent activation.

Want to know?

1.  Where and how does the process of clonal expansion take place and what is needed for the process to occur?
2.  How do antibodies help to clear and eliminate antigen out of the body?
3.  What is the 3 signal process involved in T cell dependent activation of B cells?
4.  What happens during isotype switching？ 

What we learned?

1.  B cells release IgM antibodies initially before changing to IgG, IgA, or IgE after the stimulation of cytokines by Th2 cells.
2.  B cells produce specific antibodies with the help of IL- 5 and IL-6 after undergoing clonal expansion.
3.  3 signal processes that are involved in T cell dependent  activation of B cells:
   - Antigen recognition and binding by B cell
   - Interaction of B cell and T cell
   - Cytokines released by T helper cell 
4.  Memory B cells are derived from the clones of B cells making the highest-affinity antibodies. They can last in the body for decades. 
5.  IL-4 cytokine secreted by CD4 Th2 cell helps in initiating the proliferation and clonal expansion of B cells. 

]]> 2021-11-23 07:14:36 UTC https://padlet.com/2039832/idwivveoxtj3zzqe/wish/1907768795 2039832 https://padlet.com/2039832/idwivveoxtj3zzqe/wish/1907769007 What we know?

1. T-cell has only surface receptors.
2. T-cells interact with antigen via MHC molecules.
3. Antigens need to be processed into peptides
4. CD4 T cells will differentiate into either Th1 or Th2
5. CD8 T cells will differentiate into Cytotoxic T cell

Want to know?

1. What do T cells require for activation?
2. What happens when T cells are activated?
3. What mediators are released when T cells are activated?
4. What are the roles of T cells in immune response?

What we learned?

3 signals to activate T cells:

1. Antigen Recognition
2. Co-stimulators
3. Cytokines (IL-2)

Activation of CD8 T cells:

1. Direct activation by APC
   APC with high expression of B7 and MHC1 antigen complexes --> Activate naive T cell --> Cytotoxic T cell
2. Helper T cell-assisted activation
   APC with low expression of B7 need assistance from Th cell --> Th cell interact with APC to increase its expression of B7
3. Activation by cytokines
   Activated Th cell secretes IL-2 & APC secreting IL-12--> activate and proliferate cytotoxic T cells

]]> 2021-11-23 07:14:44 UTC https://padlet.com/2039832/idwivveoxtj3zzqe/wish/1907769007