immunoglobulin-G4 (IgG4)

Function: - generally binds to polysaccharid antigens - does NOT bind complement Pathology: - major subclass of antibasement membrane antibody in bullous pemphigoid - IgG4 disease Pharmacology: - natalizumab is a recombinant humanized IgG4-kappa monoclonal antibody Laboratory: - IgG4 in serum increased in autoimmune pancreatitis & pancreatic cancer (IgG4 disease) - IgG4 Ag in tissue

Related

IgG4 Ag in tissue IgG4 disease IgG4 in serum

Properties

SIZE: MW = 150 kD COMPARTMENT: plasma SECRETED-BY: plasma cell SUBUNITS: Ig-gamma (2) MOTIF: Ig heavy chain variable region NAME: Ig heavy chain variable region heavy chain constant region-1 MOTIF: cysteine residue {CH1.SITE1} MODIFICATION: cysteine residue {CH1.SITE2} cysteine residue {CH1.SITE2} MODIFICATION: cysteine residue {CH1.SITE1} cysteine residue {C-TO-CH1} MODIFICATION: cysteine residue {C-TO-CL} hinge region MOTIF: cysteine residue {HINGE1} MODIFICATION: cysteine residue {HINGE1} cysteine residue {HINGE2} MODIFICATION: cysteine residue {HINGE2} heavy chain constant region-2 MOTIF: cysteine residue {CH2.SITE1} MODIFICATION: cysteine residue {CH2.SITE2} cysteine residue {CH2.SITE2} MODIFICATION: cysteine residue {CH2.SITE1} heavy chain constant region-3 MOTIF: cysteine residue {CH3.SITE1} MODIFICATION: cysteine residue {CH3.SITE2} cysteine residue {CH3.SITE2} MODIFICATION: cysteine residue {CH3.SITE1} immunoglobulin light chain (2) MOTIF: Ig light chain variable region NAME: Ig light chain variable region light chain constant region MOTIF: cysteine residue {CLSITE1} MODIFICATION: cysteine residue {CL.SITE2} cysteine residue {CL.SITE2} MODIFICATION: cysteine residue {CL.SITE1} cysteine residue {C-TO-CL} MODIFICATION: cysteine residue {C-TO-CH1}

References

Medical Knowledge Self Assessment Program (MKSAP) 11, American College of Physicians, Philadelphia 1998

Components

immunoglobulin gamma chain (Ig-gamma) immunoglobulin light chain