Flashcards in Lecture 45: B Cells and Antibodies Deck (19)
B Cells are important because they make _______.
B Cells recognise whole (native) _____ _____ whereas T Cells recognise _____ / ___ Complexes.
- Protein Antigens
- Peptide / MHC Coomplexes
B cells are activated by (only secrete antibodies if):
- Recognition of antigen
- CD4+ Help
B Cells are _____ that develop in the ____ _____. They are the only cell that secretes ______. They express unique antigen receptors. Plasma cells are activated by __ Cells that secrete antibody. Memory B Cells provide '_____'.
- Bone marrow
Mature B and T Cells tend to be sent to the ___ ____.
- Lymph node
Just like T Cells, B Cells express a unique __ ____ _______. This enables the recognition of a wide variety of antigens. BCR gene __________ is responsible for this.
- B Cell Receptor
In The B Cell receptor has 2 _______ regions, changing them changes the antibodies _______.
Three functions of antibody:
- Complement Activation`
- Ab binds to surface strustures on microbes, blocking their ability to attach to host cells
- Binds to toxins preventing them from
- Bind to surface of pathogen
- Facilitates uptake by phagocytes
- Have two binding sites and can agglutinate bacteria, this increases the efficiency of uptake
- IGA / IGM etc.
What's so important as IgG?
- It's the most abundant Ig class in blood.
- Opsonises / Neutralises
- Ig class that crosses placenta: provides 'passive immunity'.
- Targets virus / bacteris
- Present in secretion such as tears, saliva, mucus, and breast milk
- Defence of mucous membranes, esp. gut
- Present in breast milk
- 'Passive Immunity'
- Present in blood at low concentrations
- Immunity to multicellular parasites
- Allergic reactions
- e.g. Penicillin modifies cell proteins, IgE responses to penicillin-modified proteins can induce hives or anaphylactic shock
- Expressed on naive B Cells
- Together with IgM, acts as antigen receptor (BCR)
- Specific function unknown
- First Ig class produced after initial exposure to antigen.
- Expressed on naïve B cells
- Very effective inactivating Complement Function
- Targets extracellular bacteria
- Acts as antigen receptor (BCR)
Humoral immunity is:
- Antibody mediated immunity
The basic antibody unit is made up:
- 2 identical heavy chains, and 2 identical light chains