What is Chemotaxis? Help!

Question

I know it is involved with the immune reaction, but I'm not clear on it. If you also know about a.) a simple explanation of complement protein action, and b.) the difference between Phagocytosis and Antibody Mediated immunity (AMI), that would be fabulous.

If not, I'd LOVE to hear about Chemotaxis. Thanks.

Answer 1

chemotaxis is the excretion of chemicals from a male speciaes in response to a female species.. something like that

Phagocytosis is the process in wich phagocytes engulf bacteria and take the usefull substances and destroy it

Answer 2

chemotaxis, in the context of immunology, is used to describe the movement of neutrophils (a type of white blood cell) toward inflammation (from tissue injury) as a direct result of chemicals released by the tissue to attract the neutrophils towards it (the chemicals would be called "chemoattractants" because they chemically attract the neutrophils toward them)

Neutrophils have the ability to phagocytose any microorganism that may be hanging around the tissue injury. This means that it can "eat" up the microbe and basically get rid of it.

Phagocytosis isn't specific to different microbes- for example, bacteria X and bacteria Y can both be eaten by the same neutrophil. there's no differentiation of "oh, this particular neutrophil can only eat X type bacteria and this can only eat Y". As opposed to this, antibody-mediated immunity involves having a specific antibody for a specific microbe. So an antibody for bacteria X is not the same as an antibody for bacteria Y. Also, an antibody does not phagocytose a microbe itself, rather it is involved in a complex process at the end of which a phagocyte is directed to eat up the microbe.

Besides specificity, another difference between regular old phagocytosis and antibody-mediated immunity is that in the latter, the system has the ability to create memories. So for example, if you were infected with chickenpox in your childhood, your antibody mediated immunity created antibodies specifically tailored for chickenpox. In the future if you are exposed to chickenpox again, your immune system will be able to whip up the antibodies against it superfast because it has saved that memory.

The complement system is another non-specific immune defense (which means that like the neutrophil, it will destroy a microbe regardless of what the microbe is) Basically, a complement protein recognizes an antigen-antibody complex (an antigen is basically a protein of the microbe) and goes through a cascade of events which ends with the phagocytosis of the antigen-antibody complex.

I hope this makes sense. Immunology is a pretty complex subject and it certainly isn't easy to explain! I know that some of my explanations aren't exactly in scientific lingo but this is how it all makes sense to me!

Answer 3

There are some wonderful videos in YouTube:

http://www.youtube.com/results?search_qu...

You should look for it in a Microbiology text book, or an Immunology text.