Robert...I always enjoy your informative posts.  I was surprised that you
didn't mention the term "killed virus" vaccine (that Rusmir referred to as a
"disabled" virus in his post above yours), versus a "live virus" vaccine
(which can be risky - especially with people who have compromised immune
systems).  I believe the vast majority of vaccines for the public are
"killed" (eg influenza), with exceptions like the "live" anthrax vaccine for
our troops (please correct me if I'm wrong).

Could you elaborate a little on how they "kill" or "disable" a virus so it
can be used with a high degree of safety in a vaccine.  You don't have to
get into too many details - just a rough description, would be okay.  I have
always wondered about this.  Thanks...Pete

Single organisms have been around longer than man has. They have adapted and
have learned to evade host immune systems.
There is specific and non-specific immunity. What ever the end result is
depends on the host and the bug interactions.
They don't know the specifics of why or how the immune system produces
certain antibodies or cells or cytokines and under what circumstances those
might be. If they did we would have an AIDS vaccine by now or a malaria
vaccine etc.
With influenza we have a virus that changes and thus evades immunity. With
parasites you have the worm wraping itself with host tissue and becomes
stealth. With TB you have the bug living in a cell, macrophage, actually
living and growing in a cell intended to kill bugs. You have bacteria
secreting coagluase enzyme that walls off itself from host immune cells.
The body has sensors that detect an invader and generate a wide array of
cells that go to work. It is broad and as well as specific in the hopes of
destroying the bug.

Yes. It's called passive immunity. The CDC went into the field against Ebola
virus with plasma from people who survived the infection. The limiting
factor is the amount of antibodies and the quality of protection, both of
which are unknown.
Immune globulin is injected all the time with hepatitis A exposure and with
other virus exposures such as hepatitis B.
Synthetic antibodies ie monoclonal antibodies from clonal tissue cells
hybridomas are used clinically for testing and used as carriers for drug
delivery in cancer.
If they had a monoclonal antibody already then that would mean they already
had a vaccine as that is what a vaccine is or at least have a neutralizing
antibody.

To greatly oversimplify, a mammal's immune systems has a bunch of
templates that it 'tries' when it encounters (and 'recognizes') a
foreign protein.  When one matches, it begins to produce the antibody
in massive quantities.  You asked earlier why a disease like smallpox
can kill, despite the immune sytem producing antibodies against it.
The answer is that the disease organism can sometimes do a lot of
damage before the immune sytem can mount an effective response.

Again, greatly oversimplifying, the immune system 'remembers' an antigen
it has produced antibodies to in the past, so if it encounters the
same or a related antigen again, it can ramp up a defense much faster.
It also keeps a lower level of these antibodies around for varying
periods.  In the case of smallpox, this may be lifelong.  For other
diseases it may be months, years or decades.  This is the principle
behind vaccination.  Modern vaccines often contain only non-infective
material, like viral protein coats, that stimulate immunity without
any risk of disease.  Some vaccines target the protein toxin the disease
organism produces, rather than the microbe itself.  Diphteria and
tetanus vaccines work this way, preventing symptoms while other parts
of the immune system tackle the microbes by more generic methods.

There are some very intricate feedback systems that enable the immune
system to 'know' that the defense is working.

Biological systems, unlike designed or engineered ones, are ornately
complex, because, to use a programmer's metaphor, they grew by accretion,
patch on patch, kludge on kludge.  There are innumerable special cases,
unrelated redundant mechanisms, and just immense quantities of detail
and exceptions.  Note that autoimmune diseases, where the immune system
gets 'confused' and attacks normal body tissues, are very common and
include lupus, type I diabetes, rheumatoid arthritis and many others.
The immune system can also overreact and do more damage than the
invading organism, as in SARS and avian flu.

Nobody can give you a brief summary of how it works that's much more
informative than the above.  If you are interested, take the suggestion
already given to read Scientific American and similar sources.  You
can also try to find an immunology textbook or popular work that is
at a level that suits your interest.

This method has been in use for perhaps 100 years.  Until fairly
recently, antiserums were produced by vaccinating animals and
harvesting antibody-containing serums from their blood.  As described
to you before, this provides only a passive immunity that lasts at most
weeks to months.  Immunoglobulins collected from people who have
survived some disease are sometimes used in special cases, as with
Ebola virus.  If you get a dirty wound, you may be given tetanus
antitoxin to protect you until your own immune system can mount a
defense.  This used to be a serum collected from immunized horses, but
has no doubt been superseded by a less allergenic method of
production.

Also it should be noted that one can not necessarily naturally and
effectively  produce antibodies to all antigens.  It is somewhat dependent
upon the major histocompatibility complexes (MHC) gene complex that one
inherits or that is currently prevalent in the population.  Then there is
nature and oral tolerance.  Think about all that foriegn protein most of us
consumed for dinner this evening.  Thanks to the aggregates of lymphoid
patches located along the intestines (Peyer's patches) we are not all having
acute lower GI emergencies.