PROGRAM AREA REPORTS

CANCER IMMUNOLOGY PROGRAM

The focus of the Cancer Immunology Program Area has continued to be the immunotherapy of cancer. Immunotherapy is currently at a critical stage of development with many groups working on protocols for treatment of a number of tumors. It is very important that scientists and physicians working in this field have a thorough understanding of each others’ reagents. These include antigen-antibody systems, immunoadjuvants, and preparative techniques. In addition, details of clinical protocols must be well worked out to ensure maximum comparability and reproducibility among independent groups. These demands of the current field of immunotherapy are demonstrated in the Cancer Immunology Program Area.
The two annual scientific meetings of this program area focused on the “Immunotherapy of Cancer and its Basis in Fundamental Research.” An important topic in both seminars was the definition and description of immunoadjuvants and their immunophysiologic properties. These agents included BCG, newer preparations of BCG cell-wall skeletons, cell-wall skeletons of other micro-organisms, and synthetic analogues. Emphasis was placed on improved adjuvant properties with decreased toxicity. The role of cellular immunity in tumors and the mechanisms by which cellular immunity can be modified were thoroughly discussed. Finally, a number of investigators reviewed results of immunotherapy in tumors of a number of sites and the prospects for improved results based on the properties of newer adjuvants.
In addition to these two scientific meetings, three U.S. scientists were invited to the “International Symposium on Cancer Immunotherapy and its Immunological Basis” at Osaka, May 28-29, 1977. The proceedings of this symposium were published as GANN monograph on Cancer Research, Volume 21, April 1978, by Tokyo University Press.
As a result of these scientific meetings, active exchanges of both resources and personnel have been undertaken.
Because of the importance of the reagents used to the results in basic and clinical immunotherapy research, exchange of resources has focused on these reagents. The U.S. side has received from Japan quantities of BCG and BCG cell-wall skeleton as well as Nocardia rubra cell-wall skeleton for use in experimental models. The Japanese have received from the U.S. two breeding pairs of strain-2 guinea pigs as well as a quantity of DTIC for use in an immunochemotherapy protocol.
During this two-year period, two American and three Japanese exchange visitors spent periods from one month to one year working in host country laboratories. The focus of the longer visits was work with techniques and systems similar to those used by the visitor in his home laboratory. These visits allowed actual laboratory experiences to develop working understandings of similarities and differences in methods and results between laboratories involved. The shorter visits focused on the development of understanding necessary for undertaking cooperative or parallel clinical trials in immunotherapy.
Already, parallel independent clinical trials in immunotherapy with BCG, BCG cell-wall skeleton, and other adjuvants have been initiated. In support of these and future clinical trials, exchange of information on planning and implementation of clinical trials in both countries and collaboration on evaluating the comparative efficiency of BCG cell-wall skeleton and whole BCG vaccines in a guinea pig hepatoma model have been actively pursued.
The plans for the future development of the Cancer Immunology Program Area involve two parallel efforts. The highly productive exchange of laboratory personnel will continue. The immediate future will see emphasis on exchange of techniques for intrapleural immunotherapy with BCG cell-wall skeleton. The second, longer term effort will see continued development of cooperative and collaborative design of clinical trials of immunotherapy. Because of the need for large numbers of patients to evaluate changes in the immunoadjuvants used, this program of cooperative trials allows the evaluation of techniques and results in the shortest possible time. In addition, the exchange of immunoadjuvants that are chemically more defined and purified will ensure interinstitutional reproducibility.