This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend 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 Hersh, E. M. Articles by Drewinko, B. Search for Related Content PubMed PubMed Citation Articles by Hersh, E. M. Articles by Drewinko, B.

Specific Inhibition of Lymphocyte Blastogenic Responses to Mitogens by a Factor Produced by Cultured Human Malignant Lymphoma Cells¹

Departments of Developmental Therapeutics and Clinical Pathology, The University of Texas M. D. Anderson Hospital and Tumor Institute at Houston, Houston, Texas 77025

A glass-adherent human lymphoma cell line was found to produce an inhibitor of human in vitro lymphocyte blastogenic responses. The responses to mitogens, antigens, and allogeneic leukocytes were inhibited over 90%, as assayed by DNA synthesis or morphology. The effect was not associated with cytotoxicity and was reversible by washing the inhibited cells. The material was a nondialyzable, heat-stable protein. Its activity was not affected by its deoxyribonuclease and ribonuclease but was destroyed by Pronase. Most important, the inhibitor was species and tissue specific; it did not inhibit mouse lymphocytes or a variety of human tissue culture cell lines. The relationship of this material to regulation of lymphoid function and to the etiology and pathogenesis of cancer is discussed.

¹ Supported by Contract PH 43 68 949 from the Collaborative Research Program, Transplantation Immunology Branch, National Institutes of Allergy and Infectious Diseases, NIH, Bethesda, Md. 20014.

Received 4/ 2/73. Accepted 9/28/73.