August 15, 1941
Dr. Karl Landsteiner
The Rockefeller Institute for Medical Research
66th Street and York Avenue
New York, New York
Dear Dr. Landsteiner:
I have nothing much new to report regarding our serological experiments. Dr. Dan Campbell is now back at work here, and he
and Dr. Pressman are beginning to obtain some new results. One result of interest is the analysis of a precipitate formed
by substances like resorcinol or phloroglucinol with two attached groups. These precipitates all have the molecular ratio
of antibody to antigen equal approximately to one, which indicates strongly that the antibodies are bivalent, since the antigens
are bivalent.
I have just returned from a stay at the Stanford University Hospital with Dr. Thomas Addis. I learned from him that he thinks
that nephritis following scarlet fever or other infection is perhaps the result of some abnormality in immunological mechanism.
I asked if anyone had ever observed the incidents of nephritis or similar kidney damage in rabbits or other experimental animals
after injection with ordinary antigens or with azoproteins. He thought that no such observation had been reported, but he
felt that it would be wise to ask you about this. There is no good way of inducing nephritis in animals at present, and
if Addis is right in thinking that the immunological mechanism is responsible and if also it is found possible to produce
nephritis by injection of antigens, a study of this phenomenon might well lead to some significant results with regards to
the proper treatment of scarlet fever patients to avoid subsequent nephritis. With best regards, I am
Sincerely yours,
Linus Pauling
