June 27, 1944

Dear Dr. Hanson:

I have received notice of the action of the Executive Committee of The Rockefeller Foundation in providing support for the work in immunology being carried out under the direction of Professor Sturtevant and myself for another year. I am glad to express to you my thanks for your help in making it possible for us to carry on this work, which is, I think, going along very well.

I am very much encouraged by the progress which has been made in recent years in the study of proteins, as shown, for example, by Neurath’s review article on denaturation. The use of quantitative methods is providing us with a body of reliable information, and, although proteins are so complex that we can not hope that a final and complete solution of the problem of their structure will ever be obtained, we can, I think, look forward to getting, in our lifetime, a reasonably good insight into the general principles of protein structure.

I have continued to think about your tentative plan for a post-war congress on proteins. Such a congress would be very valuable indeed, in more than one way.

Sincerely yours,

Linus Pauling

June 27, 1944

Dr. Dan H. Campbell

Linus Pauling

Immunizing antigens

I suggest that we make an effort to find an immunizing antigen of known structure. Let us first take a synthetic resin of suitable nature, grind it up into very fine particles, and couple the particles with arsanilic acid or some similar group. These coupled particles would then be tested with anti-B serum, which should agglutinate them. If it does, some of the coupled resins could be injected into rabbits and guinea pigs to test immunizing antigenicity.

Perhaps the amberlites would be good resins to try in this way.

I think also that some dyes with very large molecular weight, such as Bismarck brown and nigrosine, should be coupled with arsanilic acid and tried in this way.

Linus Pauling

LP:jr

cc to David Pressman