Effect of synthesized constituents in the L-tryptophan product on the differentiation of eosinophils and the induction of IL-6: a possible cause of eosinophilia-myalgia syndrome.

While the pathogenesis of eosinophilia-myalgia syndrome (EMS) remains obscure, the ingestion of L-trypophan (LT) and possibly certain constituents in the LT product might be associated. We investigated the effect of chemically synthesized substances, 1,1'-ethylidene bis[tryptophan] (EBT) and its decomposition product, 1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid (MTCA) recently identified in the implicated LT, on the eosinophil differentiation and the induction of IL-1 and IL-6. EBT and MTCA alone did not support colony formation.

IL-1-induced production of IL-2 and IFN-gamma in subclones of human T-cell derived leukaemia HSB.2 cells: regulation by phytohaemagglutinin-mediated (poly)phosphoinositide breakdown and cyclic AMP.

A human T-leukaemic cell line, HSB.2-C5B2, which produces high levels of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) when stimulated with phytohaemagglutinin (PHA) plus IL-1, was recloned to obtain spontaneous variants in IL-2 production in response to the stimuli. In these subclones, the ability of one clone to produce IL-2 correlated well with that to produce IFN-gamma.

Interleukin 1 regulation of interleukin 2 and interferon-gamma gene activation in a human leukemic HSB.2 subclone.

The role of interleukin 1 (IL1) in causing IL2 and interferon-gamma (IFN-gamma) production and their associated gene activation has been studied in a human leukemic HSB.2 subclone. One of the subclones, HSB.

Signal requirement for interleukin-1-dependent interleukin 2 production by a human leukemia-derived HSB.2 subclone.

We have previously established subclones from human leukemia-derived HSB.2 cell line that produced high levels of interleukin (IL) 2 when stimulated with phytohemagglutinin (PHA) and IL-1. Herein, we investigated the signal requirement for IL-2 production, particularly concerning the role of IL-1 in this system.

Effects of anti-Tac antibody on the response of large granular lymphocytes to interleukin-2.

Large granular lymphocytes (LGL), which consist of a unique population comprising almost all of the natural killer (NK) cell activity, were separated from peripheral blood mononuclear cells by sequential depletion of monocytes and conventional discontinuous Percoll density gradient sedimentation. The LGL populations thus obtained exhibited significant levels of interferon-gamma (IFN-gamma) production and proliferation, as well as augmentation of NK cell activity in response to interleukin-2 (IL-2). Among these IL-2-driven phenomena, only IFN-gamma production was markedly inhibited by the monoclonal anti-Tac antibody, which presumably recognized the IL-2 receptor, whereas the proliferative response and the augmentation of NK cell activity were only minimally affected by the same antibody, even at the higher concentration.