FIVE CLASSES OF IMMUNOGLOBULIN1 - together by a polypeptide...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
FIVE CLASSES OF IMMUNOGLOBULINS   These are: IgG IgM IgA IgD IgE   Each class has a different role in the immune response. IgGs, IgDs, and IgEs have the Y-shaped  structure. IgMs and IgAs are usually two or more monomers joined together.    See  TABLE 17.1 P 487  for a sketch of the structures and a summary of the characteristics.      1. IgG—these antibodies account for about 80% of the antibodies circulating in blood. They  can cross the walls of blood vessels and enter tissue fluids. They can cross the placenta to give  passive immunity to the fetus. Functions: Protects against circulating bacteria and viruses Neutralizes bacterial toxins Triggers the complement system Enhances phagocytosis      2. IgM—5 - 10% of circulating antibodies. One IgM molecule consists of five monomers held 
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: together by a polypeptide called a J chain. This produces a large molecule which generally is too big to leave blood vessels. Functions: • Type involved in reactions to “wrong” ABO group blood cells • Aggregates antigens (lumps them together) • Triggers complement system • Enhances phagocytosis Overall, these antibodies are less effective than IgG antibodies, but IgMs can be produced quickly in response to a first encounter with an antigen. . IgD---only tiny amounts of this class are found in serum (0.2% of circulating antibodies). These are found in blood and lymph, and on the surface of B cells. Functions: • Act as antigen receptors on the surface of B cells • No known function in serum...
View Full Document

This note was uploaded on 01/23/2012 for the course MCB MCB2010 taught by Professor Smith during the Fall '09 term at Broward College.

Page1 / 2

FIVE CLASSES OF IMMUNOGLOBULIN1 - together by a polypeptide...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online