1,721,046 research outputs found
Immunohistochemical Staining of Plastic (Methyl-Methacrylate)-embedded Bone Marrow Biopsies Applying the Biotin-free Tyramide Signal Amplification System
Immunohistochemistry of trephine bone marrow biopsies plays a prominent role in diagnostic assessment of a broad spectrum of non-neoplastic and neoplastic hematologic and metastatic diseases. We tested the quality of immunohistochemical stainings in sections of methyl-methacrylate-embedded core biopsies prepared according to the so-called Hannover-method of cold polymerization using the novel biotin-free tyramide signal amplification system in comparison to the alkaline phosphatase-conjugated ' EnVision ' method. Examining a large panel of immunohistochemical markers, the amplification system proved to be a highly sensitive technique substantially superior to the EnVision-AP method in reliably detecting the antigenic determinants of the target cells and referred to the intensity of immunoprecipitations
Exophytic benign mixed epithelial stromal tumour of the kidney: case report of a rare tumour entity
Abstract Background Mixed epithelial and stromal tumour (MEST) represents a recently described benign composite neoplasm of the kidney, which predominantly affects perimenopausal females. Most tumours are benign, although rare malignant cases have been observed. Case report A 47-year-old postmenopausal female presented to the urologist with flank pain. A CT scan of the abdomen showed a 30-mm-in-diameter uniform mass adjacent to the pelvis of the left kidney. Surgical exploration showed a tumour arising from the lower anterior hilus of the left kidney. The tumour could be excised by preserving the kidney. By intraoperative frozen section the tumour showed characteristic features of MEST with epithelial-covered cysts embedded in an "ovarian-like" stroma. Additional immunohistochemistry investigations showed expression for hormone receptors by the stromal component of the tumour. Discussion MEST typically presents in perimenopausal women as a primarily cystic mass. Commonly, the tumour arises from the renal parenchyma or pelvis. The tumour is composed of an admixture of cystic and sometimes more solid areas. The stromal cells typically demonstrate an ovarian-type stroma showing expression for the estrogen and progesterone receptors. Conclusion MEST represents a distinctive benign tumour entity of the kidney, which affects perimenopausal woman. The tumour should be distinguished from other cystic renal neoplasms. By imaging studies it is difficult to distinguish between a benign or malignant nature of the tumour. Thus, intraoperative frozen section is necessary for conservative surgery, since the overall prognosis is favourable and renal function can be preserved in most cases.</p
Chemokine-mediated distribution of dendritic cell subsets in renal cell carcinoma
Abstract Background Renal cell carcinoma (RCC) represents one of the most immunoresponsive cancers. Antigen-specific vaccination with dendritic cells (DCs) in patients with metastatic RCC has been shown to induce cytotoxic T-cell responses associated with objective clinical responses. Thus, clinical trials utilizing DCs for immunotherapy of advanced RCCs appear to be promising; however, detailed analyses concerning the distribution and function of DC subsets in RCCs are lacking. Methods We characterized the distribution of the different immature and mature myeloid DC subsets in RCC tumour tissue and the corresponding normal kidney tissues. In further analyses, the expression of various chemokines and chemokine receptors controlling the migration of DC subsets was investigated. Results The highest numbers of immature CD1a+ DCs were found within RCC tumour tissue. In contrast, the accumulation of mature CD83+/DC-LAMP+ DCs were restricted to the invasive margin of the RCCs. The mature DCs formed clusters with proliferating T-cells. Furthermore, a close association was observed between MIP-3α-producing tumour cells and immature CCR6+ DC recruitment to the tumour bed. Conversely, MIP-3β and SLC expression was only detected at the tumour border, where CCR7-expressing T-cells and mature DCs formed clusters. Conclusion Increased numbers of immature DCs were observed within the tumour tissue of RCCs, whereas mature DCs were found in increased numbers at the tumour margin. Our results strongly implicate that the distribution of DC subsets is controlled by local lymphoid chemokine expression. Thus, increased expression of MIP-3α favours recruitment of immature DCs to the tumour bed, whereas de novo local expression of SLC and MIP-3β induces accumulation of mature DCs at the tumour margin forming clusters with proliferating T-cells reflecting a local anti-tumour immune response.</p
CD4+CD56+blastic tumor of the skin: cytogenetic observations and further evidence of an origin from plasmocytoid dendritic cells
We here report on a case of a blastic tumor, recently described to belong to a new entity sharing phenotypic similarities with blood derived plasmocytoid dendritic cells and formerly regarded as belonging to the group of natural killer cell lymphomas. Besides immunophenotypic characteristics such as the absence of T- cell markers and almost complete absence of markers of the myeloid lineage, these tumors express CD4, CD56 and CD123, the receptor for interleukin-3. Moreover, using the comparative genomic hybridisation technique, CGH, we demonstrate a gain of chromosome 7q, 22 and a loss of chromosome 3p and 13q. Since this type of hematologic disorder often shows its primary manifestation in the skin and often runs a rapidly fatal course, it is important to distinguish this from other types of primary cutaneous lymphomas
Aberrations of the CDKN2A network components p16, p14, p53 and Rb in primary cutaneous B-cell lymphomas: Rb phosphorylation status is a possible parameter for subgroup differentiation
Cold Storage Injury to Rat Small-bowel Transplants—Beneficial Effect of a Modified HTK Solution
Increased number of mature dendritic cells in Crohn's disease: evidence for a chemokine mediated retention mechanism
Background and aims: Activation of T cells by dendritic cells ( DC) is thought to play a pivotal role in induction and maintenance of Crohn's disease. Detailed analyses however concerning the phenotype and maturation of DC as well as the mechanisms underlying their recruitment are still lacking for Crohn's disease. Methods: Different myeloid and plasmacytoid DC subsets were characterised by immunohistochemistry. Expression of the so-called "lymphoid' chemokines CCL19, CCL20, and CCL21 was determined by real time reverse transcription-polymerase chain reaction in Crohn's disease and normal controls. Furthermore, expression of CCL19, CCL20, and CCL21 as well as their receptors CCR6 (for CCL20) and CCR7 (for CCL19 and CCL21) was characterised by immunohistochemistry and, in addition, their cellular localisation was determined by double immunofluorescence investigations. Results: Colonic tissue affected by Crohn's disease was characterised by an increased number of mature myeloid DC forming clusters with proliferating T cells. In keeping with their advanced maturation, DC possess the chemokine receptor CCR7. Increased expression of the CCR7 ligands CCL19 by DC themselves as well as CCL21 by reticular cells and lymphatic vessels was observed in Crohn's disease, thereby causing the matured DC to be trapped at the site of inflammation. Conclusion: Our results demonstrate that autocrine and paracrine actions of lymphoid chemokines in Crohn's disease may lead to increased numbers of mature DC away from their usual migration to lymphoid organs and result in the development of a tertiary lymphatic tissue within the bowel wall maintaining the autoimmune inflammation in Crohn's disease
Evidence for a role of Langerhans cell-derived IL-16 in atopic dermatitis
Background: The factors controlling infiltration of inflammatory cells into atopic dermatitis (AD) lesions remain to be fully explored. Recently, epidermal cells in lesional AD were reported to contain increased messenger (m)RNA levels of IL-16, a cytokine that induces chemotactic responses in CD4(+) T cells, monocytes, and eosinophils. Objectives: We sought to determine the expression of IL-16 in epidermal cells in normal skin and skin from AD lesions and to investigate whether Langerhans cell (LC)-derived IL-16 may contribute to the initiation of atopic eczema. Methods: The cutaneous expression of IL-16 was investigated by in situ hybridization and immunohistochemistry. Expression of IL-16 was also investigated in freshly isolated LCs and in keratinocytes by intracellular cytokine staining, quantitative real-time RT-PCR, and ELISA. Results: Low levels of IL-16 mRNA, but no stored IL-16 protein, were detected in keratinocytes and LCs isolated from normal skin. Synthesis, storage, and secretion of IL-16 could be induced in LCs, but not keratinocytes, by activation with phorbol ester and ionomycin. In normal skin (n = 10) neither keratinocytes nor LCs expressed IL-16. In contrast, IL-16 was contained in approximately 40% of CD1a(+) LCs in patients with active AD (n = 16). IL-16 expression in LCs in patients with AD correlated with the number of infiltrating CD4+ cells (r = .72, P = .0017) and was completely downregulated parallel to the clinical response of AD lesions to topical treatment with FK506. Conclusion: LC-derived IL-16 may participate in the recruitment and activation of inflammatory cells in AD
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