Immunity, infection, malignancy and aging: possible immunity restoration and tumor prevention

The incidence and gravity of infectious diseases in aged humans were known and feared before the age of antibiotics. Today the phenomenon, even if forgotten, still exists in old people's hospices where cross-infection flourishes. Although death in the elderly as a result of hospice-induced pneumonia may not attract public attention, a proportion of the public is still affected by death from cancer in the old. Their reaction is understandable, as it is at about 40 years of age that aging-related spontaneous tumors start to appear, after which their incidence tends to increase. The same phenomenon has been observed for spontaneous tumors in mice, in which they appear after 16 months of age. After this age, we have observed the decrease of T- and B-lymphocyte immune functions and their possible restoration parallel to tumor appearance prophylaxis, with the application of bestatin after the said 16 months. This cell regulator is also able to restore the CD4+ CD8- lymphocyte count in humans (possibly lowered after the age of 40 yr), but only if the CD4- CD8+ count is also reduced. A trial on the possible prevention or retardation of human tumor appearance by application of bestatin after the age of 40 yr is indicated.