We demonstrate here that EL4-6.1 cells, a mouse thymoma that expresses high levels of membrane interleukin (IL)-l receptors, produce IL-IB as an autocrine regulatory factor. Endogenous IL-IB sustains both proliferation and apoptosis: during the exponential phase, it mainly promotes proliferation, while during the plateau phase of cell growth, it induces death by apoptosis. Additionally, we show...

Superoxide dismutase mimetic copper(II) complexes, such as copper(II)(3,5-diisopropylsalicylate)2 (CuDIPS), inhibit phorbol ester stimulated tumor promotion in mouse skin. Therefore, CuDIPS was tested as a potential inhibitor of another effect of phorbol esters, induction of interleukin 2 (IL2) synthesis, in the mouse thymoma cell line EL4. CuDIPS inhibited phorbol ester induced IL2 production ...

A modified model of adjuvant arthritis is described that permits simultaneous quantitative measurement of the humoral and the cellular immune response to a secondary immunogen (el4 cells) in the arthritic rat. Application of the new model system to mechanism studies is illustrated with cyclophosphamide. The drug is shown to suppress adjuvant arthritis by a combined anti-inflammatory and immunos...

It has been demonstrated previously that cannabinol (CBN) differentially modulates interleukin-2 (IL-2) protein secretion by T cells with a corresponding change in extracellular signal-regulated kinase activity. The objective of the present studies was to further investigate the molecular mechanism by which CBN enhances IL-2 gene expression using the EL4 T cell line. We demonstrate here that st...

A CD44 blockade drives leukemic cells into differentiation and apoptosis by dislodging from the osteogenic niche. Because anti-CD49d also supports hematopoietic stem cell mobilization, we sought to determine the therapeutic efficacy of a joint CD49d/CD44 blockade. To unravel the underlying mechanism, the CD49d(-) EL4 lymphoma was transfected with CD49d or point-mutated CD49d, prohibiting phosph...

Phorbol esters, acting via activation of the protein kinase C family of protein serine/threonine kinases, are able to exert profound effects on various cellular functions. In this study, we used the EL4 thymoma cell line to study the potential role of "downstream" protein serine/threonine kinases in cellular responses to phorbol esters. In wild-type EL4 cells, addition of phorbol ester caused a...

Sequential thymidine radiograms from rats labeled on days El3 and E14, and killed at daily intervals thereafter, were analyzed to trace the migratory route and settling pattern of neurons of the inferior olive. Longsurvival thymidine radiograms from perinatal rats injected on day El4 were used to subdivide the inferior olivary complex on the basis of neurogentic criteria. The inferior olivary n...

The tyrosine kinase inhibitor herbimycin A was found to block NF-kappa B stimulation in response to interleukin-1 and phorbol 12-myristate 13-acetate in EL4.NOB-1 thymoma cells and phorbol 12-myristate 13-acetate in Jurkat T lymphoma cells. The effect appeared not to involve inhibition of tyrosine kinase activation as neither interleukin-1 nor phorbol 12-myristate 13-acetate induced major chang...