The nude mouse is ham without a thymus.In most vertebrates the thymus constitutes a vital part of the immune system. If the thymus is surgically removed from adult mice, no immediate changes can be observed in immune responses, - even if present day refined laboratory techniques can demonstrate alterations in the function of lymfjhocytes of such animals. If the thymus 2's surgically removed from mice within 24 hours of birth, however, there is rapid marked impairment in the animals’ cell—mediated immune responses, and in the formation of humoral antibodies to a number of antigens.
Now, the nude mouse is born without a thymus. This would make one suppose that the made mouse does represent a base line for study of thymic function in the immune system. And furthermore, that the absence of the thymus could be exploited in studies of other biological systems, e.g. malignant tumour tissue, transplanted in the nude mouse.
In the following we summarize some of the evidence in favour of this
