September 2, 1971
Dear Dr. Phillipson:
I am sorry to have missed your phone call, but I was obliged to spend more time than anticipated outside the New York area.  When I returned, I found you had already left for Boston and Sweden.
However, I have been recently persuaded by my own confusing data that the best way for us to approach the study of transformed mammalian cells is to infect our own cells with our own virus, monitoring carefully for transformation, contaminating C-type particles, gs antigen, and virus recovery by cell fusion.  I feel our biochemistry has outdistanced our biology, and I am trying to rectify this situation by examining freshly transformed lines we are capable of establishing and checking ourselves.
I am, of course, still interested in your cell lines, but at present, I do not have time to grow and work with them. Perhaps when the project has progressed further, I could ask you for some.
Again, thanks for your interest in helping us.
Yours,
Harold E. Varmus, M.D.