Induction of IL-4 secretion by the radiation leukemia virus (RadLV): Role in autocrine growth stimulation of RadLV infected pre-leukemic cells
✍ Scribed by Eitan Yefenof; Catherine Ela; Moshe Kotler; Ellen S. Vitetta
- Publisher
- John Wiley and Sons
- Year
- 1992
- Tongue
- French
- Weight
- 598 KB
- Volume
- 50
- Category
- Article
- ISSN
- 0020-7136
No coin nor oath required. For personal study only.
✦ Synopsis
lntrathymic inoculation of radiation-leukemia virus (RadLV) into C57BL/6 mice induces a population of pre-leukemic (PL) T cells which progress into clonal, mature thymic lymphomas after a latency period of 3 to 5 months. In order to understand how PL cells are retained in the thymus for a prolonged period of time we determined whether RadLV infected cells secrete and/or respond to a T-cell growth factor that may be involved in the long-term maintenance of a thymic PL-cell pool. We have previously found that in vitro proliferation of RadLV-infected PL cells is IL-4-dependent. Here we show that RadLV induces IL-4 secretion and IL-4 receptor (IL-4R) expression in normal thymic lymphocytes. RadLV-infected PL thymocytes express IL-4R and secrete IL-4. Their IL-4 secretion could be enhanced if incubated in the presence of RadLV and this enhancement was inhibited by anti-RadLV antibodies. Several RadLV-induced lymphoma lines secreted IL-4 and/or expressed L 4 R , but these features were not essential for their continuous growth. The results suggest that RadLV induces IL-4-dependent autocrine growth which maintains a population of PL T cells in the thymus. Transition from a PL state to overt thymic lymphoma involves emancipation of a PL cell from IL-4 dependency.