Animal models disadvantages

This section is devoted to the definition and comparison of the three nonrodent animal models (dog, ferret, and monkey) in terms of experimental procedures, environmental and dietary requirements, as well as advantages and disadvantages of use in safety assessment testing. 

Advantages and Disadvantages. Advantages of using monkeys in safety assessment studies include their phylogenetic proximity, as well as their physiological, behavioral, and, often, metabolic similarities, to humans (Table 16.13). An example is the similarity between the ovarian cycle of female monkeys and women (Mazue and Richez, 1982), which makes the monkey the ideal animal model for reproductive studies. Another advantage associated with most species of monkeys used in safety assessment studies is that they are much smaller than nonrodents such as the dog and, thus like the ferret, require less test compound. 

Compounds tested in a more physiological 3-D environment show increased predictability of in vivo responses and help to span the gap between 2-D tissue culture and animal models. There is also evidence that 3-D cultures can identify active compounds that would fail to show their potential in 2-D (56, 57). The complexity of 3-D cultures can be increased by the addition of one or more cell types (fibroblasts, endothelial cells) and/or culture with different media, substrates, or oxygenation conditions. However, a disadvantage is that there is still a lack of simple, standardized, and reliable 3-D protocols that allow their incorporation into the pre-clinical high-throughput validation and drug evaluation process, although there have been several advances in this area in recent years (30, 58-61). 

In addition to whole animal models, in vitro studies are generally used to complement and specify the data obtained using perfused organs, tissue or cell cultures, and microsomal preparations. The use of these models allows a more detailed or partial study of the effects of PAC and can decrease the ethical concerns, but it has disadvantages as well. For instance, the cells are often not easy to culture and maintain, which in turn results in diluted samples. 

Especially this latter disadvantage gave rise to the search for other screening methods, in a number of cases aimed at the induction of a depressive state in animals [7]. The realisation of such animal models, however, is laborious and their superiority to the commonly used techniques has still to be presented. The... 

In the following section, some of the most common in vitro models will be described with their advantages and disadvantages, some animal models will be briefly mentioned, and it will be explained why they are not in favor by the detergent industry. I will then discuss the tests performed on human volunteers with the existing methods developed to quantify the effect of surfactant on skin physiology. 

Advantage and Disadvantage of Animal and In Vitro Models of Immunotoxicity.. 74 References.75... 

ADVANTAGE AND DISADVANTAGE OF ANIMAL AND IN VITRO MODELS OF IMMUNOTOXICITY... 

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