Oral Everolimus for Treatment of a Giant Left Ventricular Rhabdomyoma in a Neonate—Rapid Tumor Regression Documented by Real Time 3D Echocardiography

The presented case reports on successful treatment with everolimus in a neonate with left ventricular giant rhabdomyoma. The authors used a different dosage regime compared to literature and documented rapid tumor regression by 3D echocardiography.     

Isolation of DNA from the centromere of human chromosome 7 by microdissection

Centromeres remain the least characterized regions of human chromosomes because they have a very high content of repetitive DNA. Here, we describe a micro-dissection library from the centromeric region of human chromosome 7 and its use for generating sequence tagged sites (STSs). The library contains about 1500 clones with an average insert size of 150 bp and only about 15% of the clones harbour repetitive human DNA. Seven clones hybridizing to alphoid DNA were found to correspond to a fragment of the D7Z2 alphoid array on chromosome 7, thus confirming the origin of the library. A number of clones not containing known repetitive DNA were used to generate STSs that identified yeast artificial chromosomes (YACs) and in turn allowed the STSs to be placed on the physical map. One STS is located between the two Genethon genetic markers closest to the centromere on the q side. Another STS was located 3–4 cM away in 7q11.2, while a third identified YACs containing both low-copy and alphoid sequences that are not yet mapped but are clearly centromeric. The library therefore comprises a collection of sequences from the centromeric region of chromosome 7 that can be used to generate STSs and to map the entire centromeric region.This revised version was published online in November 2005 with corrections to the Cover Date.     

Immune responses to weakly immunogenic virally induced tumors II. Suppressive effects of the in vivo carried tumor YAC

Unprimed spleen cells from A and C57BL/6 mice could not produce cytotoxic responses to their syngeneic tumors: a Moloney virus-induced in vitro subline YAC-1 and a Rauscher virus-induced in vitro subline RBL5, respectively. Spleen cells from A and C57BL/6 mice immunized with YAC-1 or RBL5 (which cross-react serologically) generated significant syngeneic cytotoxicities after cultivation in vitro. The in vivo carried tumor of A mice, unlike the in vitro sublines, could not stimulate a priming effect. In contrast, YAC stimulated the formation of suppressor cells in both A and C57BL/6 mice. The suppressor cells abrogated the priming effect of the syngeneic tumors, but not the priming effect of the allogeneic tumors. Furthermore, YAC did not suppress normal allogeneic anti-tumor responses. The theoretical and the practical implications of these studies are discussed.     

Active detachment involves inhibition of cell-matrix contacts of malignant melanoma cells by secretion of melanoma inhibitory activity

Melanoma inhibitory activity (MIA) has been identified as a small protein secreted from malignant melanoma cells. Recent results revealed a direct interaction of MIA and epitopes within extracellular matrix proteins including fibronectin. The aim of this study was to analyze functional consequences mediated by this interaction. Here we show that MIA interferes specifically with attachment of melanoma cells to fibronectin, a phenomenon we refer to as active detachment. Antibodies inhibiting binding of alpha4beta1 and alpha5beta1 integrins to fibronectin cross-react specifically with MIA, suggesting that MIA shares significant structural homology with the binding pockets of these integrins and thereby masks the respective epitopes on extracellular matrix molecules. Several peptides derived from fibronectin and from a phage display screening were tested with respect to a potential MIA-inhibitory effect. In vitro tests identified two peptides affecting MIA function; both inhibited growth of melanoma metastases in vivo. In summary, we conclude that MIA may play a role in tumor progression and spread of malignant melanomas via mediating active detachment of cells from extracellular matrix molecules within their local milieu. Further, our results suggest that inhibiting MIA functions in vivo may provide a novel therapeutic strategy for metastatic melanoma disease.     

Evidence for a calcium regulated, bidirectional intronic promoter in the murine TCR V{alpha}1 gene

Previous studies of the TCR chain gene have located promoterelements 5' to the start of the various V genes. The only fullycharacterized enhancer for the entire chain gene (V, J andC genes) has been located {small tilde}3 kb from the 3' endof C. We now report the existence of additional regulatory elementslocated in the introns of several murine V genes (V1, V3 andVB6.2.16). In the case of V1, this element appears to be a promoterwith bidirectional activity that is not T cell specific. Interestingly,upstream of the promoter in the antisense strand, an open readingframe has been found that codes for a small molecular weightprotein ({small tilde}60 amino acids) that contains a prollne-richregion and a tyrosine-isoleucine motif that has homology toIgß (the B29 gene product). A rabbit antiserum madeagainst this sequence has confirmed its existence by Westernblot and immunoprecipitation. Thus this V1 intronic promoterhas the potential not only to induce the formation of a truncatedV1 gene product, but also regulates the expression of a smallmolecular weight protein that may be involved in lymphocyteantigen receptor signaling. The activity of this promoter isregulated by changes in intracellular calcium. In the presenceof ionomycin the promoter is down-regulated in the sense directionand its activity is enhanced in the antisense direction. Thisresult suggests that this promoter can act differentially toproduce two very different gene products. The bidirectionalV1 promoter appears to be the first in the Ig superfamily toinduce potentially functional proteins in both directions.     

Characterization of the epitope recognized by a mAb that reacts differentially with murine suppressor T cells

Although reliable antibodies are available that distinguishhuman suppressor T (T_s) cells from CTL and other T cells, feware available for murine T_s cells. We have developed a mAb (984D4.6.5)that, in the presence of complement, depletes alloantigen-specificT_s cells but not CTL. This antibody recognizes activated TT_scells but not their precursors. In these studies, flow cytometricanalysis demonstrates that 984D4.6.5 reacts with several T_scell hybridomas, cloned T_h cell lines and WEHI-3 (a myelomonocytictumor cell line). Reactivity was not detected with BW5147, T_hcell hybridomas, cloned T_h cells, CTL lines and hybridomas,B cell lines, thymocytes, splenocytes, bone marrow cells nora variety of tumor cells. Among 984D4.6.5 positive lines, expressionis heterogeneous and the number of cells expressing high levelsof the epitope is increased when the hybridomas are maintainedat a relatively high cell density. Neuriminidase and pronasedeplete the epitope recognized by mAb 984D4.6.5. Protein synthesisand glycosylation inhibitors also reduce expression of thisepitope. These observations suggest that the epitope recognizedby 984D4.6.5 is a carbohydrate linked to a polypeptide. Thisantibody was tested by ELISA for binding to a large panel ofcarbohydrates and glycollpids coupled to BSA. The only one thatbound 984D4.6.5 was LS tetrasaccharide c (NeuNAc2-6Galpß1-4GIcNAcß1-3GaIß1-4Glc),an O-linked carbohydrate. Comparative analysis shows that boththe sequence and the linkage of these sugars are essential tothe reactivity with the 984D4.6.5 antibody. This epitope isexpressed by a glycoprotein of-200 kDa, as shown by Westernblots. The identity of this glycoprotein remains to be determined,but indirect evidence suggests that it is not CD45.     

Orbital surgery – perioperative problems and results

Fragestellung: Orbitotomien nehmen innerhalb der Ophthalmochirurgie auf Grund der involvierten anatomischen Strukturen und des daraus resultierenden Spektrums m?glicher perioperativer Probleme eine Sonderstellung ein. Um einen überblick über die Art und H?ufigkeit intra- und postoperativer Probleme bei Orbitotomien zu erhalten, führten wir eine retrospektive Auswertung an unserer Klinik durchgeführter Orbitotomien durch. Patienten und Methode: Es wurden 48 Orbitotomien bei 46 Patienten berücksichtigt, die zwischen 08/1995 und 02/1998 operiert wurden. Ergebnisse: Schwerwiegende intraoperative Komplikationen waren mit zwei transfusionspflichtigen Blutungen und einer Liquorfistel selten. Sie wurden interdisziplin?r behandelt. Postoperativ traten vorübergehende funktionelle St?rungen mit guter Rückbildungstendenz wie Visusminderungen (35 %), Motilit?tsst?rungen mit oder ohne Doppelbildwahrnehmung (20 %) und Lidfehlstellungen auf. Ihnen liegt v. a. die postoperative ?dem- und H?matombildung zugrunde. Persistierende Funktionseinschr?nkungen waren dagegen selten (10 %). Schlu?folgerung: Unsere Untersuchung zeigt, da? perioperativ bei Orbitotomien v. a. vorübergehende funktionelle Einschr?nkungen auftreten, die sich rasch zurückbilden. Schwere Komplikationen sind dagegen selten, treten v. a. intraoperativ auf und k?nnen eine interdisziplin?re Therapie erfordern.      

Immunosuppressive Compounds Exhibit Particular Effects on Functional Properties of Human Anti-Aspergillus TH1 Cells

Allogeneic hematopoietic stem cell transplant (HSCT) recipients are at high risk for invasive aspergillosis. Whereas adoptive immunotherapy transferring donor-derived anti-Aspergillus T_H1 cells has been shown to be beneficial for HSCT recipients suffering from invasive aspergillosis, little is known about the impact of commonly used immunosuppressants on the functional properties of anti-Aspergillus T_H1 cells. Anti-Aspergillus T_H1 cells were coincubated with different concentrations of methylprednisolone, cyclosporine (CsA), mycophenolic acid (MPA), the active component of mycophenolate mofetil, and rapamycin. Immunosuppressants were tested in concentrations reflecting common target levels in serum and in significantly lower and higher concentrations. Apoptosis of anti-Aspergillus T_H1 cells, as well as proliferation and production of gamma interferon (IFN-γ) and CD154 upon restimulation, was evaluated in the presence and absence of immunosuppressive compounds. All dosages of CsA, MPA, and methylprednisolone significantly decreased the number of viable anti-Aspergillus T_H1 cells in the cell culture, which was due partly to an impaired proliferative capacity of the cells and partly to an increased rate of apoptosis. In addition, CsA significantly decreased the number of IFN-γ-producing cells and had the highest impact of all immunosuppressants on IFN-γ levels in the supernatant. CsA also significantly decreased the expression of CD154 by anti-Aspergillus T_H1 cells. Variant dosages of immunosuppressants exhibit particular effects on essential functional properties of anti-Aspergillus T_H1 cells. Our findings may have an important impact on the design of clinical trials evaluating the therapeutic benefit of anti-Aspergillus T_H1 cells in allogeneic HSCT recipients suffering from invasive aspergillosis.