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Manfred Kneilling,
Reinhard Mailhammer,
Lothar Hültner,
Tanja Schönberger,
Kerstin Fuchs,
Martin Schaller,
Daniel Bukala,
Steffen Massberg,
Christian A Sander,
Heidi Braumüller,
Martin Eichner,
Konrad L Maier,
Rupert Hallmann,
Bernd J Pichler,
Roland Haubner,
Meinrad Gawaz,
Klaus Pfeffer,
Tilo Biedermann, Martin Röcken
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ABSTRACT: Signaling through tumor necrosis factor receptor 1 (TNFR1) controls bacterial infections and the induction of inflammatory Th1 cell-mediated autoimmune diseases. By dissecting Th1 cell-mediated delayed-type hypersensitivity responses (DTHRs) into single steps, we localized a central defect to the missing TNFR1 expression by endothelial cells (ECs). Adoptive transfer and mast cell knockin experiments into Kit(W)/Kit(W-v), TNF(-/-), and TNFR1(-/-) mice showed that the signaling defect exclusively affects mast cell-EC interactions but not T cells or antigen-presenting cells. As a consequence, TNFR1(-/-) mice had strongly reduced mRNA and protein expression of P-selectin, E-selectin, ICAM-1, and VCAM-1 during DTHR elicitation. In consequence, intravital fluorescence microscopy revealed up to 80% reduction of leukocyte rolling and firm adhesion in TNFR1(-/-) mice. As substitution of TNF(-/-) mice with TNF-producing mast cells fully restored DTHR in these mice, signaling of mast cell-derived TNF through TNFR1-expressing ECs is essential for the recruitment of leukocytes into sites of inflammation.
Blood 07/2009; 114(8):1696-706. · 9.90 Impact Factor
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ABSTRACT: Experimental tumor vaccination and adoptive T-cell therapies show that interferon-gamma (IFN-gamma)-producing CD4(+) T helper cells (Th1) can be highly effective in tumor prevention and therapy. Unexpectedly, first vaccine trials in humans revealed that tumor immune therapy may not only be protective, but, on the contrary, even promote tumor progression. Here, we analyzed T-cell immune responses to the epithelial cell adhesion molecule (EpCAM), one of the most common tumor-associated antigens (TAA) serving as immune target in colon cancer patients. Th-cell priming against EpCAM inevitably resulted in interleukin-4 (IL-4)-dominated Th2 responses, even under most stringent Th1-inducing conditions. These EpCAM-reactive Th2 cells rather promoted growth of EpCAM-expressing tumors. To analyze the role of IL-4 in tumor immune evasion, we generated EpCAM-reactive Th1 cells from IL-4.ko mice. These Th1 cells provided tumor-specific protection and established highly protective Th1 memory responses, even in naive BALB/c mice. Inhibition of tumor growth by Th1 cells resulted in intra-tumoral expression of cytokines of the IL-12 family and of IFN-gamma. Preventing activation-associated death of Th1 cells further increased intratumoral IFN-gamma expression and improved therapeutic efficacy. Thus, human TAA may promote tumor immune evasion by strongly favoring Th2 development.
Blood 03/2009; 113(15):3494-502. · 9.90 Impact Factor
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Archives of dermatology 06/2008; 144(5):692-3. · 4.76 Impact Factor
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Clinical Infectious Diseases 09/2007; 45(3):352, 395-6. · 9.15 Impact Factor
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ABSTRACT: It is established that primary malignant melanomas (pMM) can be infiltrated by T-cell populations with predominantly one T-cell clone. As pMM generally express multiple tumor-associated antigens (TAA), here we used laser-capture microdissection (LCM) to isolate different tumor-infiltrating lymphocyte (TIL) clusters in order to determine whether pMM are infiltrated only by one single clone or whether the TAA may attract various T-cell populations. As T-cell receptor (TCR) clonality is a useful tool for the demonstration of specific T-cell clones, we analyzed 56 pMM, three cutaneous melanoma metastases, and 15 pairs of pMM with a sentinel lymph node (SLN) for clonal rearrangements of the (TCR) gamma chain gene. We detected the clonality of TCR gamma chain gene in 25 of 56 pMM, and in 10 of 17 SLN studied. In four of the 15 pairs of primary tumor and SLN, we found clonal TCR gamma in both the melanoma and the SLN, with two pairs harboring the identical clone. As we detected different clones in pMM and the corresponding SLN, we subsequently performed LCM in 21 malignant melanomas with multiple lymphocytic clusters for the presence of focal clonal T cells in different regions of the melanoma. In seven melanomas, both clusters of TILs showed the same rearranged TCR gamma chain gene and in five of the seven biopsies the clonal rearrangement occurred in different variable (V) regions of the TCR gamma chain gene. These tumors showed infiltration by more than one clone. In 10 biopsies TCR clonality was restricted to one cluster, while the second microdissected sample of the infiltrate was polyclonal. In conclusion, within one primary malignant melanoma several T-cell clones with different rearrangements may occur. The balance between these clones may decide on the progress of melanoma.
Journal of Investigative Dermatology 03/2006; 126(2):393-8. · 6.31 Impact Factor
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ABSTRACT: Replacement of mycophenolate mofetil, cyclosporine, or tacrolimus by sirolimus results in regression of Kaposi's sarcoma (KS) in organ transplant recipients.1- 3 In these patients, clearance from KS might result either from reduced immunosuppression or from the direct antiangiogenic effects of sirolimus.1 +
Archives of Dermatology 144(5):692-693. · 3.89 Impact Factor