This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Levinthal, J. D. Articles by Eaton, M. D. Search for Related Content PubMed PubMed Citation Articles by Levinthal, J. D. Articles by Eaton, M. D.

The Effect of Cortisone and Thymic Extract in Mouse Viral Leukemia^{1, 2,}

Department of Bacteriology and Immunology, Harvard Medical School, Boston, Massachusetts

Highly susceptible, newborn F₁ hybrids of AK/Jax x C3Hf/Bi/Gs/L³ strain mice, referred to as AK/Z, received Gross Passage A virus i.p., and the leukemogenic process was altered by 2 forms of intervention affecting the target organ, the thymus.

Death from leukemia was delayed but not prevented by monthly courses of cortisone, 1 mg s.c. daily for 3 days. The delay was inversely proportional to the age at which the hormone injections were begun. Delay was possible even when these were begun during the period in which the leukemogenic process was already completed or nearly complete, as judged by previous studies of pathogenesis.

In mice thymectomized at 5 weeks of age, the interrupted leukemogenic process could not be reinitiated by i.p. injections of thymic extract from 1–2 normal mice every 6–7 days, continued for 5 months. Injections of normal mouse thymus in normal newborn AK/Z mice resulted in early lymphocytic lymphoma in 4 of 20 mice.

¹ Presented before the American Association for Cancer Research at the annual meeting in Toronto, May 23, 1963.

² This research was supported by a grant from the USPHS, National Cancer Institute, No. CA-04965.