CZECHOSLOVAK ACADEMY OF SCIENCES AH

BIOLOGICAL INSTITUTE
NA CVICISTI 2 - PRAHA 6

Czechoslovakia

Tro Jo Lederberg

Department of Ganeties
Stanford University

Medicel Center

Palo Alto, California

January 7, 1961

Dear Dr. Lederberg,

Se Oe Rene OS TO SU ae SY ee A ae eS SO ee ee OE Om ee HR Se ane Sos Om we ME men OO ee Oe ee nee Oe Oe Ee ee me Ow

The Czechoslovak Academy of Sciences readily agreed to our proposal to hold an
international symposium on "Mechanisms of Immunological Tolerance" in 1961 which
would be timed in relation fo the symposium on “tansplantation" organized by the
Ciba Foundation in London, November 1961, to provide an opportunity for more
detailed discussion of various questions. It was agreed in advance with Professor
Medawar (the Ciba Foundation Symposium is being organized an his suggestion) to
discuss some problems at the London Symposium and some problems in Prague in the
manner that a duplicity would be excluded and on the contrary, the two Symposia
would form one broader whole.

Membership to the symposium on mechanisms of immunological tolerance will be
limited to a maximum of 50. We shall be very pleased and interested to receive
offers of contributions regarding such que stions as :

induction of tolerance in embryos and newborn snimals;

tolerance-like phenomena in adukts (involving immunological parelysis,
radiation=induced tolerance, antigen overloading, Sulzberger-Chase
phenomenon, exhaustive sensitization, enhancement);

the fate of antigen in unresponsive organisms;

partial tolerance;

specificity of tolerance.
The programme of the syxuposium is, however, not limited by the above-mentioned
subjects and other suggestions will be appreciated, The communications presented
may include either the most recent experimental findings of one’s ow work or may
follow more general views and deal with attempts of a theoretical interpretation
of the phenomena of immunological tolerance and unresponsive states in a broader
sense. We would like to accomplish that this symposium should deal with the present
state of the questions mentioned above and arrive to conclusions in the form of

working hypotheses which would open new approaches to further experimental analysise

St 11 - 4780 59
‘I am now writing to invite fou to be a menber of the symposium which will be held
on Wednesday, Sth, Thursday, 9th, and Friday, 10th November, 1961, at the House of
the Czechoslovak Academy of Sciences in Liblice, in the vicinity of Praguee The sym-
posium will follow the style of five to six half-day sessions over the three days and
ample time will be allowed for discussion of the papers presented. It is necessary to
have @ full text of the pregentations to the end of August 1961 at the latest so that
each member of the symposium could receive copies of the speakers’ papers in advance.
The complete record of the commnications including discussions will be published in
the form of a monography on the symposium, in English.

The Czechoslovak Academy of Sciences will expect that you will be guest of the
Academy during your stay in Czechoslovakia. The funds available for this purpose
being limited, I regret that your travelling expenses cannot be provided for, but
I hope that it will be possible for you to cover them from other sources.

I would very much appreciate your personal participation and hope that you will
find it possible to come and take an active part in this symposium, in November 1961.
I would be grateful for an early reply to this invitation indicating at the same time
a tentative title of your paper.

I look very much forward to hearing that you will be with us on this occasion.

In the near future, I shall send you full details of the programme and the particie
pants.

With best regards,

Yours sincerely,

Milan HaSek