II. B cells and T cells

bone marrow form multipotent stem cells go on to become

• lymphoid (b/t) or myeloid stem cells (red, white, platelet))

B cells

• Membrane contain y shaped receptors

• 4 polypeptides: 2 heavy, 2 light chains

  • Chains connected through covalent bonds, forming disulfide bridges

• Constant (C ) (sequence of amino acids usually constant) and variable (V) regions (sequence of amino acids can vary)

• Epitope (antigen binding sites) 

• When activated, receptors secreted as antibodies (immunoglobulins) 

T Cells

• Also have Ag receptors

• a and B chains (alpha and beta)

• V and C regions

• Don't target pathogens directly, only bind Ag on surface of host cells

• (kinda like water soluble cells)

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