Iv - University of Salford Institutional Repository

Immunotherapy is an experimental technique that takes advantage of
the body's natural defenses against tumour cells. Cells often display
new surface antigens called tumour-specific antigens. These antigens
can be recognised by the body's immune system jus as the body can
recognize and destroy f_nvading bacteria. The white blood cells of the
body recognize invading bacteria as foreign and destroy them. White
blood cells also appear able to recognize tumour cells and are able to
destroy them. For some not well understood reasons, in some
individuals the body's immune system does not function properly. A
poorly functioning immune system could increase the likelihood that the
individual will develop cancer or of developing persistent forms of
infectious diseases. Immunotherapy is based upon the idea that cancer
may be controlled by stimulating the immune system, in much the same
way as the Salk vaccine protects against polio. Various laboratories
around the world are experimenting with immunotherapy as a treatmeit
for cancer. Patients used in these studies are usually those how have
little chance of recovery using conventional treatments. These
patients are usually inoculated with a substance that acts as a
generalised stimulus of the immune system, or with a combination of
such substances with living or dead tumour cells or tumour cell surface
antigen material. The substance usually used as a generalized stimulus
of the immune system is BCG (Bacillus of Calmette and Guerin), a
weakened strain of tuberculosis bacteria that has been used to treat
tuberculosis.
This material appears to activate the immune system.
Vaccines are also made with living or dead tumour cells, or parts of
tumour cells.
Immunotherapy seems to be potentially promising for
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