CLASS I vs CLASS II MOLECULES

CLASS I vs CLASS II MOLECULES - while class II molecules...

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

View Full Document Right Arrow Icon
CLASS I vs CLASS II MOLECULES While class I and class II molecules appear somewhat structurally similar and both present antigen to T-cells, their functions are really quite distinct. First, class I molecules are found on virtually every cell in the human body. Class II molecules, in contrast, are only found on B-cells, macrophages and other "antigen-presenting cells" (APCs). Second, class I molecules present antigen to cytotoxic T-cells (CTLs) while class II molecules present antigen to helper T-cells (TH-cells). This specificity reflects the third difference, the type of antigen presented. Class I molecules present "endogenous" antigen
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: while class II molecules present "exogenous" antigens. An endogenous antigen might be fragments of viral proteins or tumor proteins. Presentation of such antigens would indicate internal cellular alterations that if not contained could spread throughout the body. Hence, destruction of these cells by CTLs is advantageous to the body as a whole. Exogenous antigens, in contrast, might be fragments of bacterial cells or viruses that are engulfed and processed by e.g. a macrophage and then presented to helper T-cells. The TH-cells, in turn, could activate B-cells to produce antibody that would lead to the destruction of the pathogen....
View Full Document

This note was uploaded on 11/05/2011 for the course BIOLOGY MCB2010 taught by Professor Jessicadigirolamo during the Fall '10 term at Broward College.

Page1 / 2

CLASS I vs CLASS II MOLECULES - while class II molecules...

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