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 HighWire Citing Articles via Google Scholar Google Scholar Articles by Okamura, S. Articles by Mak, T. W. Search for Related Content PubMed PubMed Citation Articles by Okamura, S. Articles by Mak, T. W.

Heterogeneity of Human Thymocytes and a Malignant T-Lymphoblast Cell Line, MOLT-3¹

Ontario Cancer Institute and Department of Medical Biophysics, University of Toronto, Toronto M4X 1K9 [S. O., C. L., T. W. M.], Harold Tennebaum Research Department, Mount Sinai Hospital, Toronto M5G 1X5 [B. E. C.], and Division of Immunology, Research Institute, Hospital for Sick Children, Toronto, Ontario, M5G 1X8 [E. W. G.] Canada

The purpose of this paper was to study the heterogeneity of human thymocytes and leukemic cells of the T-cell line MOLT-3 by velocity sedimentation. Analysis of the subpopulations of thymocytes demonstrated that they represent a heterogeneous population of cells with respect to their size, proliferative activity, and presence and quantities of terminal deoxynucleotidyl transferase and human thymus leukemia-associated antigen, a thymic isozyme of adenosine deaminase (HThy-L/ADA). Only a minor subpopulation of thymocytes (large cells) was in active cycle. The highest level of HThy-L/ADA was associated with the main subpopulation of thymocytes sedimenting at 3 to 4 mm/hr while low amounts of the HThy-L/ADA antigen (enzyme) were found in the minor fractions of the small and large cells. The distribution of terminal deoxynucleotidyl transferasepositive cells indicated that most, but not all, thymocytes contain the enzyme.

Analysis of the T-cell line MOLT-3 showed that these cells could be separated into subpopulations with different biochemical and biological properties. More than one subpopulation of cells was capable of DNA synthesis. In contrast to the thymocytes, all fractions of MOLT-3 cells contained high amounts of HThy-L/ADA. The proportion of terminal deoxynucleotidyl transferase-positive cells as a function of sedimentation velocity was also quite constant although there was a slight but reproducible drop in the percentage of these cells in the slowly sedimenting fractions. The percentage of cells with receptors for sheep erythrocytes also remained high in fractions separated on the basis of size, although a consistently higher percentage was found in smaller cells. These studies indicated that thymus cells as well as the malignant T-cell line MOLT-3 can be separated on the basis of sedimentation velocity into subpopulations with different biological and biochemical properties. The data also indicated that the heterogeneity of MOLT-3 line cannot be explained solely on the basis of volume changes due to cell cycle, suggesting that they may represent heterogeneous populations of cells.

¹ Supported by the Ontario Cancer Treatment and Research Foundation, the National Cancer Institute of Canada, and the Medical Research Council of Canada.

² Present address: First Department of Internal Medicine, Kyushu University, Japan.

³ To whom requests for reprints should be addressed, at Ontario Cancer Institute, 500 Sherbourne Street, Toronto, Ontario, Canada M4X 1K9.

Received 6/16/80. Accepted 1/29/81.

This article has been cited by other articles:

				T. Ishida, S. Iida, Y. Akatsuka, T. Ishii, M. Miyazaki, H. Komatsu, H. Inagaki, N. Okada, T. Fujita, K. Shitara, et al. The CC Chemokine Receptor 4 as a Novel Specific Molecular Target for Immunotherapy in Adult T-Cell Leukemia/Lymphoma Clin. Cancer Res., November 15, 2004; 10(22): 7529 - 7539. [Abstract] [Full Text] [PDF]