W Hamann

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Secretion of the potentially antileukaemic cytokines IFN-gamma and TNF-alpha was investigated for CD4+ and CD8+ TCR alpha beta + T-cell clones derived from 4 leukaemia patients 3-6 weeks after allogeneic BMT. We investigated cytokine secretion in response to the activation signal accessory cells+phytohaemagglutinin+Interleukin 2. All clones derived after(More)
In this paper we reproduce the shape of X-ray emission lines observed in single non-magnetic O stars using a clumped wind model. The Chandra HETGS/MEG spectra of ζ Pup, ξ Per, ζ Ori, and ζ Oph are analyzed. From the line ratios of He-like ions the X-ray line formation regions are constrained to be located in the acceleration part of the stellar winds. To(More)
In an attempt to explore T-cell functions shortly after allogeneic bone marrow transplantation more fully, IL2- and IL4-dependent proliferation was assessed on CD4+ TCR alpha beta+ T-cell clones derived 4-6 weeks after transplantation. Both allogeneic pooled peripheral blood mononuclear cells and Epstein-Barr virus-transformed B-cell lines (BCL) could(More)
Modeling expanding atmospheres is a difficult task because of the extreme non-LTE situation, the need to account for complex model atoms, especially for the iron-group elements with their millions of lines, and because of the supersonic expansion. Adequate codes have been developed e.g. by Hillier (CMFGEN), the Munich group (Puls, Pauldrach), and in Potsdam(More)
Spectral lines formed in stellar winds from OB stars are observed to exhibit profile variations. Discrete Absorption Components (DACs) show a remarkably slow wavelength drift with time. In a straightforward interpretation , this is in sharp contradiction to the steep velocity law predicted by the radiation-driven wind theory, and by semi-empirical profile(More)
Inhomogeneous Wolf-Rayet type stellar winds are modeled in a first-order approximation, assuming that small-scale clumps are distributed with a constant volume filling factor within an interclump space which is void. Model calculations as well as analytical considerations show that the main spectral features, i.e. the strength of the emission lines, are(More)
Secretion of different cytokines may be an important T-cell effector mechanism for bone marrow engraftment, graft versus host disease and graft versus leukaemia effects after allogeneic bone marrow transplantation (BMT). Cytokine secretion and autocrine proliferative capacity of T-cell clones derived from leukaemia patients 3-6 weeks after allogeneic bone(More)