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recombinant proteins in combination with diagnostic tests to limit their use to
patients where they are least likely to induce immune reactions.
Another approach to protein therapy is in vivo production of proteins by geneti-
cally engineered cells where the delivery of proteins can be matched to the needs of
the patient and in vivo production and controlled delivery might reduce adverse
effects.
Therapeutic Monoclonal Antibodies
Compared with small-molecule drugs, antibodies are very specifi c and are less
likely to cause toxicity based on factors other than the mechanism of action. Orally
available small molecules have many targets but they may also hepatotoxic and are
involved in drug-drug interactions. They may interfere with cytochrome P-450.
From the point of view of a clean safety profi le, antibodies are extremely attractive.
They can be designed to be very specifi c with high affi nity for the target.
Antibodies have for many decades been viewed as ideal molecules for cancer
therapy. Genetic engineering of antibodies to produce chimeric or humanized
monoclonal antibodies (hMAbs) has greatly advanced their utility in molecular tar-
geting therapies. These will be described in more detail in the section on personal-
ized cancer therapy in Chap. 8. Many molecular biological and immunological
studies have revealed the targeting properties of the host immune system and the
biological mechanisms of cancer cells for a more specifi c anticancer effect. Many
clinical trials of MAbs as a single agent, or in combination protocol with current
standard chemotherapy or immunoconjugates have shown promise in the treatment
of specifi c diseases. Furthermore, novel MAb designs and improved understanding
of the mode of action of current MAbs lend great hope to the future of this therapeu-
tic approach. The accumulating results from many basic, clinical and translational
studies may lead to more individualized therapeutic strategies using these agents
directed at specifi c genetic and immunologic targets.
Cell Therapy
Cell therapy is the prevention or treatment of human disease by the administration
of cells that have been selected, multiplied and pharmacologically treated or altered
outside the body (ex vivo). The aim of cell therapy is to replace, repair or enhance
the function of damaged tissues or organs. The cells used can originate from the
patient or from a donor or from another species. Other sources include cell lines and
cells from patients’ tumors to make cancer vaccines. Cells can be encapsulated in
selectively permeable membranes that block entry of immune mediators but allow
outward diffusion of active molecules produced by the cells. Genetic engineering of
9 Personalized Biological Therapies