Immune system clinical trials

VI. Effect of Intestinal Microbiota on the Immune System Clinical Trials... 

Adjuvants are substances which can modify the immune response of an antigen (139,140). With better understanding of the functions of different arms of the immune system, it is possible to explore the effects of an adjuvant, such that the protective efficacy of a vaccine can be improved. At present, aluminum salt is the only adjuvant approved for use in human vaccines. New adjuvants such as QS-21, 3D-MPL, MF-59, and other liposome preparations are being evaluated. Several of these adjuvants have been in clinical trial, but none have been approved for human use. IL-12 has been proposed as an adjuvant which can specifically promote T-helper 1 ceU response, and can be a very promising adjuvant for future vaccine development. 

The theoretical complications posed by random chromosomal integration became a medical reality in 2002, when two children who had received retroviral-based gene therapy 2 years previously developed a leukaemic-like condition. The initial clinical trial aimed to treat X-linked severe combined immunodeficiency (SCID-X1), a hereditary disorder in which T-lymphocytes and NK cells in particular do not develop, due to a mutation in the gene coding for the yc cytokine receptor subunit. The clinical consequence is near abolition of a functional immune system. 

Alzheimer s Disease The vaccine being tested contains a small protein called jS-amyloid (AjS). This protein forms abnormal deposits, or plaques, in the brains of people with Alzheimer s disease. Researchers believe that Kji deposition causes loss of mental function by killing the brain neurons. The strategy of Aji vaccination is to stimulate the immune system to clean up plaques and prevent further A deposits. Although preclinical and Phase I studies showed the potential of the vaccine, the Phase II clinical trial was halted because 15 of 360 patients developed severe brain inflammation. Further studies showed that the A did generate the desired... 

Although IL-2 has not been approved to treat HIV/AIDS, many clinical trials using IL-2 are being conducted. The strategy is to complement the anti-HIV therapy by boosting the immune system with IL-2. The replacement... 

Early animal experiments have underlined the potential of vaccinia-based vector vaccines. Vaccinia virus-housing genes from HIV have clearly been found to elicit both humoral and cell-mediated immune responses in monkeys. Similar responses in other animals have been reported when surface polypeptides from a variety of additional pathogens have been expressed in recombinant vaccinia systems (Table 10.16). Human clinical trials are now in progress. 

Large-scale clinical trials are likely to be the only way by which any HIV vaccine may be properly assessed. In addition, a greater understanding of the molecular interplay between the viral and immune system may provide clues as to the development of novel vaccine and/or therapeutic products, e.g. a small proportion of infected individuals remain clinically... 

Wright, Karen. A Shot of Sanity You ll Get No Kick from Cocaine if Yau Take this New Vaccine. Discover, June 1999, pp. 47-48. Reports on clinical trials of a vaccine that triggers an immune system reaction that blocks the absorption of cocaine. However, while the vaccine blocks the effect of the drug, it does not block the craving. Users may be able to circumvent the vaccine by taking very high doses of cocaine or they may simply decide to stop taking the vaccine. 

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