Microbes-L10-Adaptive Immunity- Antibodies and Immunisation

what did Edward Jenner discover?

milkmen who were exposed to cowboy didn’t get smallpox- they’re exposed to something not as severe and were protected

what is important about a successful vaccination

we need to not only activate the innate system but the adaptive as it gives us memory!!

what makes up the adaptive immune system?

1. t cells

2. b cells- make the antibodies

what do vaccines need to do?

need to activate T and B cells

• T helper cells- activate other immune cells including cytotoxic T cells

• cytotoxic T cells- recognise and kill- CD8

• specific antibodies- reocgnise and bind to antigenic epitopes- plasma cells make this

what is the innate immune system comprised of?

• antigen presenting cells- such as dendritic cells and macrophages

• antigen presenting cells express- PRR’s- pattern recognition receptors

• PAMPs- pathogen associated molecular patterns- can be used in vaccines along with antigens!

difference between primary and secondary immune response

• new virus- activates everything

• infected again- reaction is bigger as you have memory bu won’t have ILLNESS! kills it straight away

what do vaccines do to your immune response?

induces a primary response- not very big but provides you with MEMORY

• can prevent you from getting ill as you have a bigger response to the “real” bug

what is the adaptive immunity comprised of?

• mediated by antigen presenting cells: dendritic cells(myeloid phagocytotic cells)

  • antigen is presenting in lymph node

• T lymphocytes- CD4

• B lymphocytes-Plasma cells

what is a B lymphocyte receptor consist of?

• antigen binding subunit- binds to a viruses antigen- highly specific that triggers immune

• 2 heavy 2 light chains- variable regions to recognise many types

• transmembrane region

• signalling unit

what are B lymphocytes and plasma cells?

• plasma cells differentiate from B lymphocytes

• B lymphocytes express antigen specific B cell receptors- secrete antibodies

• antigen specific B cells can becoming plasma cells which make antibodies and memory B cells

difference between B cells and antibodies?

same structure but B cells receptors are stuck to the membrane

• when they shed- its an antibody

B cell responses to immunisation

primary: first infection

• B cells become activated- produce antibodies- IgG and IgM

• when infection clears-get long lived plasma cells in the bone marrow and memory B cells

what is an antigen, epitope and antibody

antigen- infectious agent and is specific

epitope- specific bit hat antibodies bind to

antibody- secreted by B cells and plasma and binds to antigen

5 classes of antibodies

1. IgG- main blood antibody- mother to baby- whopping cough vaccine given to make this

2. IgM- initial immune system defence

3. IgA- as monomers- respiratory infections- in the mucous

4. IgD- also prevention in respiratory tract infections

5. IgE- immunity to parasites

what do antibodies do?

1. neutralisation of pathogens or toxins- neutralise it.

   • toxin come in through endocytosis and antibodies bind to toxin

2. opsonisation

   • innate-macrophages phagocytose and degrade them

   • in adaptive- coats pathogen in antibody to make macrophage find it

3. complement action

   • reaction of all proteins

   • cause cell lysis ad cause opsoniation

   • rpomote pro inflammatory

   • cascade