Bio 328 Immunology

Immunoglobulins: structure and Function

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Albumin

globulin

globulin

globulin

Origin

Inflammation Normal Normal Myeloma

Arne Tiselius and Elvin Kabat 1939.

2014)

1972 Noble Prize in Medicine.

Porter et al.

Nisonoff et al.

Edelman et al.

Goat anti-Human Fab binds to both L- and H-chain; goat antiHuman Fc binds

only to H-chain.

Angiotensin ll

Van der Waals surface contact between angiotensin ll and Fab fragment.

Flu virus antigen and antibody

Fab and Influenza virus antigen

Anti-HIV protease Fab

+ peptide

Fab different anti-hen egg lysozyme

Fab different small epitopes

Unbound Ag-bound

Induced-fit

Unbound Ag-bound

Anti-hemagglutinin Fab and peptide.

Antibody –Mediated Effector Functions

1.Ab-medicated clearance of pathogensa) Neutralizationb) Opsonizationc) Complement activationd) ADCC

2.Ab isotypes or classes mediate different functions3.Fc Receptors

How do Antibodies kill Cancer Cells?

1.Binding to cell surface receptors and preventing their activation.2.Interference with vascularization.3.Induction of apoptosis.4.Induction of ADCC.5.Induction of Complement fixation.6.Delivery of toxins.

IgG, IgA, IgD IgM, IgE

CH1/CH1CH1/CH1

Hinge regionCH2/CH2

CH2/CH2CH3/CH3

CH3/CH3CH4/CH4

1921 K. Prausnitz and H. Kustner1966 K and Y Ishizaka

Immunoreceptor Tyrosine Activation Motifs

B-cell Linker Protein

Bruton’s tyrosine kinase

X-linked agammaglobulinemia

The End