From: Billi Goldberg <bigoldberg@igc.org>
Subject: SV40 info
Note: non-commercial reproduction.
Archive-Number: 4854
Organization: UCLA, Computer Science Department
Date: Tue, 14 Apr 92 08:57:38 PDT

Many comments have been made on sci.med.aids and by public "experts" 
concerning the monkey kidney cell cultures used in the preparation
of the polio vaccines used in the late 50s and early 60s.

The following is from "6.  DETECTION OF A "NON-DETECTABLE" SIMIAN VIRUS 
(VACUOLATING AGENT) PRESENT IN RHESUS AND CYNOMOLGUS MONKEY-KIDNEY CELL 
CULTURE MATERIAL.  A PRELIMINARY REPORT" by B.H. Sweet and M.R. Hilleman 
of the Division of Virus and Tissue Culture Research, Merck Institute 
for therapeutic Research, West Point, Pennsylvania in the report of the 
Second International Conference on Live Poliovirus Vaccines held in 
Washington, D.C., 6-10 June 1960 (pp. 79-89).  This Scientific 
Publication No. 50 was published by the Pan American Health Organization 
and the World Health Organization.

************************************************************************

page 79.

The simian virus of monkey kidney origin present a real problem in the 
virus application of the cell culture technique.  Thus, indigenous 
simian virus may contaminate or even exclude the inoculated virus on 
passage in monkey-kidney cell culture.  Virus-infected culture fluids 
used to prepare killed poliomyelitis or adenovirus vaccine are commonly 
contaminated with simian agents and assurance must be provided for the 
inactivation of both the intended and the simian viruses in these 
vaccines.  Testing for such "intruding" viruses may be further 
complicated by the presence of such agents in the cultures used to 
perform the tests.  Finally, such simian viruses must be definitively 
excluded from any live virus vaccine intended for routine use in man 
since the long-term effect of human infection with theses agents is 
unknown and since data on short-term effect are either meager or 
entirely lacking.

All of the presently reported simian viruses derived from monkey-kidney 
cell culture have been detected in kidney-cell cultures of the same 
monkey species, either in the primary culture itself or on further 
passage.  Thus, all of the agents previously reported have been readily 
detectable and can be excluded on the basis of rigid testing in monkey 
cell cultures.  The question has often been raised concerning 
hypothetical "non-detectable" simian viruses, i.e., those agents which 
might be present in monkey kidneys but which cannot be detected by 
current procedures.

During the past two years, our virus research work has repeatedly 
uncovered what appears to be a new simian virus of Rhesus and Cynomolgus 
monkey kidney origin and which does not cause significant cytopathic 
change in kidney-cell cultures of these same species.  the agent does, 
however, cause very marked and distinctive cytopathic changes in kidney-
cell cultures of these same species.  The agent does, however, cause 
very marked and distinctive cytopathic changes in kidney-cell cultures 
of the African green monkey, Cercopithecus aethiops, obtained from 
equatorial East Africa.  In our laboratory, we have referred to this 
virus as the "vacuolating agent", because of the prominent cytoplasmic 
vacuolation seen in infected cell cultures.  Dr. Hull has suggested this 
vacuolating virus be designated S.V. 40 and be included in Hull's C.P.E. 
Group 4."

page 85.

The vacuolating agent appears to be just "one more" of the troublesome 
simian agents to be screened for and eliminated for and eliminated from 
virus seed stocks and from live virus seed stocks and from live virus 
vaccines.  Lack of antibody response in human subjects fed polio vaccine 
containing vacuolating agent suggest lack of massive proliferation of 
the virus under the conditions employed although absence of human 
infection to some degree could not be excluded.  

The detection in green monkey kidney of this common inapparent virus 
infection of Rhesus and Cynomolgus monkey kidney represents the first 
instance of demonstration of a "non-detectable" indigenous agent in the 
monkey-kidney culture system.  Although new to simian viruses and monkey 
kidney, it is neither new nor unique to other viruses and cell culture 
systems.  Demonstration of the vacuolating agent raises the question of 
possible presence of other indigenous and inapparent monkey kidney 
agents which might be detected under different methods of testing.  It 
also raises the question of the extent to which proliferation of viruses 
inoculated into monkey-kidney cell cultures may be interfered with owing 
to the presence of such inapparent indigenous viral agents.

************************************************************************