Dr. Wallace P. Rowe 
3/29/79 
The problem is that to date it is unlikely that any single antigen can be 
identified as a unique or major component of such complexes. Immune complex 
disease may result from antibody responses to bacterial or viral antigens or a 
variety of autologous antigens as well as drug conjugates. 
I do not think that it is reasonable to expect that the creation of 
bacterial strains producing hum&h proteins will automatically result in disease 
conditions. However, even if this proved to be the case, such an organism would 
not be a greater danger for mankind than E.typhosa or P. pestis or other virulent 
organisms grown in experimental or reference laboratories. 
The issue as I see it in every human endeavour is that there is no such 
thing as a riskless activity. Do the benefits outweight the risks is the major 
consideration. These have to be considered individually. 
In the case of insulin, for instance, in terms of immunity to the hormone, 
the present situation is that millions of human beings suffering from diabetes 
are treated with antigenic foreign insulin against which they can and do form 
antibodies. Furthermore, foreign insulins have such close similarities with 
human insulin that such immune responses would be classified as potentially 
hazardous in that respect as well. Such patients would be largely benefited 
by the existence of commercially available human insulin with weaker or no 
antigenicity for humans. 
In summary, I am happy to be on record favoring the continuation of work 
in this area with appropriate caution based upon technical expertise and I feel 
that far worse consequences would result from stopping the research than 
continuing it. 
With best personal regards, 
Yours sincerely, 
Baruj Benacerraf, M.D. 
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