Humoral and Cellular Immunity

[smen]

I have this homework assignment and I can't figure out the answer to 2 of the questions. I've read all the chapters and still am lost. Could someone please guide me or give me an idea of what the answer is?

 

 

1. Describe the elements of humoral and cellular immunity that are involved in immune responses to viral infections.

 

2. What mechanisms have infectious agents evolved to defeat these elements?

 

Thank you in advance,

May

[jimmydasaint]

Are you not on holiday yet? Anyway, try here and if it does not help, give us a message.

http://www.revision-notes.co.uk/revision/271.html

 

I quote:

 

B-cells are produced in the bone marrow and are distributed through the body in the lymph nodes. B-cells respond to the ‘foreign’ antigens of a pathogen by producing specific antibodies. Antibodies are complex proteins that are released into the blood and carried to the site of infection. B-cells do not fight pathogens directly.

 

 

 

An antibody, or immunoglobulin, is a y-shaped protein molecule that is made by a B-lymphocyte in response to a particular antigen. Antibodies interact with the antigen and render it harmless. When a pathogen tries to invade the body for the first time, each of its antigens activates B-cell, which divides rapidly to produce a large population of cells. All the new cells are identical: we say they are clones, and they all secrete antibodies specific for the invading pathogen. When the infection is over, most of the newlymade B-cells die. This sequence of events is the primary immune response.

 

 

 

So that the body can respond more quickly next time, some of the activated B-cells persist in the body for several years. These memory cells ‘remember’ what the pathogen is like and, if it tries to invade again, they all divide rapidly to produce an even greater number of active B-cells, all capable of secreting specific antibody. This response is called a secondary immune response and is very much quicker and more effective than the primary response.

 

 

Dude, you have to watch these brilliant animations:

 

http://www.learner.org/channel/courses/biology/archive/animations/hires/a_hiv1_h.html

Edited July 26, 2008 by jimmydasaint
adding link to animations