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Terry E. Garner garter at unicomp.net
Mon Nov 23 22:32:29 EST 1998

I do not intend for this to be perceived as being derogatory, however your
question is from a very vague and ambiguous perspective.  Meaning that
there are several different aspects of the body's immune response to an
antigen(bacteria).  There are two basic types of immune responses,
antibody-mediated(humoral) responses and cell-mediated responses.
    The humoral immune response employs several assistants to carry out
the immune response.  This involves the myeloid system which are derived
from the bone marrow.  First the neutrophils are the first line defense in
the myeloid system and they are the most abundant leukocyte in the
blood(60-75%).  They are phagocytic(meaning cell eating) and are attracted
to the peptides which the bacteria produce.  The neutrophils are
short-lived and are rapidly exhausted, yet during this time chemical
triggers are being sent to recruit more antibody assistance.  Assistance
may come from eosinophils and/or basophils both of which are part of the
myeloid system.
The next humoral system is the mononuclear-phagocytic system which employs
the use of the macrophage.  This macrophage is also a cell eater, but it
is not short lived and will continue to function until its life span is
exceeded which ranges from weeks to a few months.  These macrophages also
secrete many enzymes and proteins which assist in antigen destruction by
either messengers to other antibody cells or to penetrate the antigen and
destroy it from the inside out.  B-cells come into play in
antibody-mediated responses by producing memory cells that are programmed
to respond to that particular antigen if it is ever encountered again.
    Cell-mediated response inlists the response of the T-cells.  T-cells
come in different forms the cytotoxic T-cell and the helper T-cell each
with there own functions.  B-cells also play a part in cell-mediated
immune responses.  In short the cell-mediated immune response is performed
just the way it sounds.  The cells in the body excrete chemical antibody
activators and produce chemicals that remain within the cell, but attach
to transmembrane proteins that signal and activate either B-cells or
T-cells depending on which is needed and which specific receptor is
signaled.  Each cell the B and T have their own particular transmembrane
receptor proteins to bind to in order to receive a signal.
This is just a very brief overview of the immune response, but it may
assist you in giving you a direction in which to proceed.
    As for bacteria they are simply spherical or rod-shaped prokaryotic
organisms with a simple basic structure.  They have a cytoplasm that
contain enzymes and ribonucleoprotein with no nucleus, they have a single
layer membrane covered by a cell wall, and some bacteria are
encapsulated.  Bacteria are considered antigens to the human body because
they are foreign and also destructive.  They can inter the body by
inhalation, ingestion, or through a wound.
Bacteria cause many illness some of which are: pneumonia, meningitis,
gonorrhea, syphylis, tuberculosis, tetanus, sinusitis, strep-throat,
typhoid fever, and the recently publicized "flesh eating bacteria".
    I hope this information has been helpful.

Syed Jamil AHMED wrote:

> I'm doing an essay in biology so I need help.Please can anyone tell me
> immune system's reaction to bacterial and what are antibodies?
>  Thankyou very much in advance!
>  Sabrina

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