Checking cosmetics for allergenicity: biochips instead of mice
Researchers of the company Hurel Corporation, working together with specialists of the cosmetics company L'Oreal, have developed the main component of a microfluidic biochip, which in the future will allow cosmetics manufacturers to do without conducting allergic tests on animals. Despite the fact that there is still a lot of work to be done to create a full-fledged device suitable for commercial use, the researchers consider their latest development an important step towards achieving the ultimate goal.
According to Robert Freedman, Chief Executive Officer of Hurel Corporation, one of the important advantages of abandoning animal testing is to reduce the cost of production. An allergic test for small animals costs the company about $ 1,000, while using a chip will significantly reduce these costs and save the lives of 25 animals. In addition, the use of human cells will reduce the number of possible errors. We should not forget about the ever-growing political pressure to abandon animal testing in general. This factor is especially important for the European market, where a complete ban on the sale of cosmetic products that have passed animal safety testing will come into effect in 2013.
The chip being developed is designed to replace the test, called the "regional lymph node test" and is often used to test new chemical compounds used in the manufacture of cosmetics. Currently, such tests are usually carried out on female mice, although some laboratories prefer an older version of the method using guinea pigs.
Chad Sandusky of the Committee of Physicians for Responsible Medicine notes that it is almost impossible to name the exact number of animals used in conducting allergic tests, since rodents are not protected by the animal welfare law in the United States and the state does not receive reports on their use. However, the committee estimates that in the United States this figure is at least 10,000 animals annually.
When an animal develops a skin allergy, dendritic skin cells move through the lymph to the lymph node, where they stimulate T-lymphocytes, thus triggering an allergic reaction. Researchers observe the resulting external manifestations, such as skin irritation.
The device being developed by Hurel Corporation will allow reproducing the interaction between the skin and the lymphatic system that develops in response to exposure to a chemical compound. The device will include two tissue structures grown in laboratory conditions (a lymph node and a fragment of skin) interconnected by a microfluidic system consisting of microchannels filled with a medium in which the chemical gradient of the compound attracting activated dendritic cells will be maintained in a special way.
The tested chemical product will need to be applied to artificial skin. In the event of an allergic reaction, dendritic cells will move to the lymph node and stimulate the T-lymphocytes located there.
The first step has already been taken: in a series of photos and (much better) in a short video, you can see how dendritic cells in a microfluidic device move along a chemical gradient. Now the developers will have to create an artificial skin and a lymph node and ensure that all components of the system work together.
In addition to creating fabric components of the device, developers will have to choose the most appropriate method for registering test results. Possible options are monitoring the proliferation of T-lymphocytes and/or changes in the concentration of molecules secreted by them. However, they hope to create the first fully functioning prototype of the device by 2011.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of TechnologyReview: Cosmetics Testing without Animals.
21.01.2010