
1368. immunologic competence and induction of neoplasms by
polyoma virus
thymectomy at 3 days of age in several
inbred strains of mice and in an f1 hybrid
resulted in a strikingly increased frequency
of neoplasms following infection with
polyoma virus.  age susceptibility was extended
to at least 30 days of age in highly
resistant c57bl mice.  the usual stigmata
associated with thymectomy at birth were
not found in the 3-day thymectomized mice.
nonetheless the methods used to restore
immunologically deficient thymectomized
neonates were also effective in restoring
the capacity to resist polyoma virus tumor
induction: adult syngeneic spleen cells,
thymus tissue in millipore diffusion chambers
and syngeneic thymus grafts.  growth
curves of polyoma virus in kidney, salivary
glands and liver were quite similar in
thymectomized and intact litter mates.
hemagglutination-inhibition antibodies deter-
mined periodically up to 30 days after
infection were also similar in both groups.
these results are discussed in terms of
a concept involving virus-specific 'tumor'
antigens and the immunologic status of the animal.
