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Birgit Ackermann

Publications and source records attributed to Birgit Ackermann.

3 recordsLinked to original sources

Leukemia vaccines.

Evidence that immunological effector mechanisms contribute to the elimination of leukemic blasts in allogeneic bone marrow transplantation supports the concept that the immune system plays a prominent role in the control of leukemic disease. For patients with high-risk acute leukemia, relapse prevention in the setting of minimal residual disease is paramount. This review discusses vaccine strategies aimed to stimulate a leukemia-specific immune response in vivo.

Cancer Vaccines↗

Rapid-cycle PCR and fluorimetry for detection of mycobacteria.

In this study we used LightCycler PCR amplification and product detection by fluorescence resonance energy transfer probes to identify mycobacteria and differentiate between Mycobacterium tuberculosis complex, Mycobacterium avium, and other nontuberculous mycobacteria. Targeting the 16S rRNA gene, three different probes specific for mycobacteria, M. tuberculosis complex, and M. avium were constructed. As few as five genome copies of target nucleic acid were detected by the probes, illustrating the high sensitivity of the system. All 33 mycobacterial species tested but none of the closely related actinomycetes and other bacteria produced a specific fluorescence signal. A specificity of 100% was also demonstrated for the M. tuberculosis complex-specific probe and the M. avium-specific probe. Within 45 min, the LightCycler method correctly detected mycobacteria and specifically identified M. tuberculosis complex and M. avium without any post-PCR sample manipulation. In view of future clinical studies, we also constructed and tested an internal control which could be used to assure successful amplification and detection of mycobacteria. Monitoring of PCR inhibition will be essential for evaluation of this system for direct detection of mycobacteria in clinical specimens. Finally, we tested our system on sputum seeded with mycobacteria and were able to detect as few as 10 organisms. At present, this system is the fastest available method for identification and differentiation of mycobacteria from culture-positive specimens and offers an excellent alternative to previously established nucleic acid amplification-based techniques for the diagnostic mycobacterial laboratory.

Bacterial Typing Techniques↗

Transgenic IL-2 expression in Ewing tumor cell lines after transfection with Starburst dendrimers and cationic liposomes.

Immunotherapy with IL-2-transduced cells requires efficient methods of gene transfer. Nonviral methods have been studied intensively in recent years. This study examined whether tumor and fibroblast cell lines established from Ewing tumor patients could be efficiently transfected with the IL-2 gene. Starburst dendrimers (Superfect), a novel transfection reagent, were chosen for a transfection study and optimal conditions for gene transfer were evaluated. Three Ewing tumor cell lines and 3 fibroblast cell lines obtained from Ewing tumor patients were analyzed. The concentration of IL-2 in the supernatant of transfected cells was measured by ELISA. All three Ewing tumor cell lines transfected by Starburst dendrimers yielded higher IL-2 levels than after lipofection. In contrast to lipofection, expression of IL-2 increased with time and peaked later. In one of three tested fibroblast cell lines, transfection using Superfect yielded higher IL-2 levels. IL-2 production was generally lower in fibroblasts as compared to Ewing tumor cell lines. Given the low toxicity of Superfect reagent and the high efficiency of transfection, this method seems to be ideal for clinical studies on the immunotherapy of Ewing tumors.

Cations↗