Antibodies Against Mimotopes of Simian Virus 40 Large T Antigen, the Oncoprotein, in Serum Samples from Elderly Healthy Subjects

Simian Virus 40 (SV40), a monkey polyomavirus, was administered to human populations by early anti-poliomylitis vaccines contaminated by this small DNA tumor virus. Data on SV40 infection in humans remain controversial. Elderly subjects represent an interesting cohort to investigate, because they were not immunized with SV40-contaminated vaccines. Taking advantage of the Italian population, the second oldest worldwide, elderly subjects (n¼237) up to 100 years old were enrolled in this study. Their sera were analyzed, by ELISA tests with synthetic peptides mimicking the viral epitopes, for IgG antibodies reacting with SV40 large Tumor antigen (Tag), the viral oncoprotein. An overall seroprevalence of 22% was revealed in subjects aged 66–100 years, ranging from 19% in individuals 66–74 years old, to 24% in subjects 82–100 years old, with a lower SV40 titer detected in the oldest group. Our data show that: (i) SV40 infection is not frequent in old individuals; (ii) the infection rate increases in elderly with the age; (iii) the antibody titer of SV40 Tag decreases with the age. In conclusion, SV40 infection seems to spread in old subjects independently from SV40-contaminated vaccines. This study seems to confirm that SV40 is also a human virus.