However, while impaired CTL-function may be a drawback in cancer therapy, it is evident that the suppression of CTLs would be of profound benefit in the treatment of autoimmune diseases and other CD8+ T cell-associated diseases, such as COPD (chronic obstructive pulmonary disease) [47] and even more, in transplantation medicine. This evidence concerns the gene CD8A and chronic obstructive pulmonary disease.