Therapie mit Stammzellen

Therapeutic use of stem cells Here the hematopoetic system of blood‐ and immune cell renewal is reviewed. Curing of chronic leucemias and malignant lymphomas is the most successful stem cell based therapy up to date. However, mismatches of histocompatibility‐complexes (HLA‐types) between receiver and donor set narrow limits to such therapies. Whether other diseases such as Parkinson could be cured by infusion of stem cells is still in question.     

Motifier: An IgOme Profiler Based on Peptide Motifs Using Machine Learning

Antibodies provide a comprehensive record of the encounters with threats and insults to the immune system. The ability to examine the repertoire of antibodies in serum and discover those that best represent “discriminating features” characteristic of various clinical situations, is potentially very useful. Recently, phage display technologies combined with Next-Generation Sequencing (NGS) produced a powerful experimental methodology, coined “Deep-Panning”, in which the spectrum of serum antibodies is probed. In order to extract meaningful biological insights from the tens of millions of affinity-selected peptides generated by Deep-Panning, advanced bioinformatics algorithms are a must. In this study, we describe Motifier, a computational pipeline comprised of a set of algorithms that systematically generates discriminatory peptide motifs based on the affinity-selected peptides identified by Deep-Panning. These motifs are shown to effectively characterize antibody binding activities and through the implementation of machine-learning protocols are shown to accurately classify complex antibody mixtures representing various biological conditions.     

Methodologies for the isolation of alternative binders with improved clinical potentiality over conventional antibodies

The availability of binders to different functional domains of the same protein or to physiologically co-operating proteins allows for the simultaneous inhibition of independent downstream signaling pathways. This multi-target approach represents a promising therapeutic strategy, as demonstrated in the case of the synergistic effect of anti-Her2 treatment based on the combined use of the trastuzumab and pertuzumab monoclonal antibodies that induce cellular cytotoxicity and impair the receptor dimerization, respectively. Therefore, a reliable selection method for the recovery of epitope-specific antibodies is highly needed. Animal immunization with short peptides resembling the epitope sequence for raising conventional antibodies represents an alternative. Panning phage displayed libraries of recombinant antibodies such as scFvs and nanobodies or of other peptide collections is another option. Although recombinant antibodies can provide the same specificity as conventional antibodies, they offer at least two further advantages: i) the protocols for the selection of epitope-specific antibodies can be rationally designed, and ii) their expression as multivalent, bispecific and biparatopic molecules is feasible. This review will analyze the recent literature concerning technical aspects related to the isolation, the expression as multivalent molecules, and the therapeutic applications of binders able to interfere with antigen functional domains. The term binder will be preferred when possible to include those molecules, such as peptides or affibodies, with at least some proven practical uses.     

Identification of amino compounds synthesized and translocated in symbiotic Parasponia

We investigated the synthesis and translocation of amino compounds in Parasponia, a genus of the Ulmaceae that represents the only non-legumes known to form a root nodule symbiosis with rhizohia. In the xylem sap of P. andersonii we identified asparagine. aspartate. glutamine, glutamated significant quantities of a non-protein amino acid. 4-methylglutamte(2-amino-4-methylpentanedioic acid). This identification was confirmed by two methods, capillary gas chromatography (GC) electron ionization (El) mass spectrometry (MS) and reverse phase high pressure liquid chromatography (HPLC) analysis of derivatized compounds. In leaf, root and nodule samples from P. andersonii and P. parviflora we also identified the related compounds 4-methyleneglutamate and 4-methyleneglulamine. Using ¹⁵N₂ labelling and GC-Ms analysis of root nodule extracts we followed N₂ fixation and ammonia assimilation in P. andersonii root nodules and observed Label initially in glutamine and subsequently in glutamate, suggesting operation of the glutamine synthetase/glutamine:2-oxoglutarate aminotransferase (GS/GOGAT) pathway. Importantly, we observed the incorporation of significant quantities of ¹⁵N into 4-methylglutamate in nodules, demonstrating the de nova synthesis of this non protein amino acid and suggesting a role in the translation of N in symbioticParasponia.     

Structural characterization of KKT4, an unconventional microtubule-binding kinetochore protein

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LncRNA NEAT1 promotes docetaxel resistance in prostate cancer by regulating ACSL4 via sponging miR-34a-5p and miR-204-5p

Docetaxel resistance remains one of the main problems in clinical treatment of metastatic prostate cancer (PCa). Previous studies identified differently expressed lncRNAs in docetaxel-resistant PCa cell lines, while the potential mechanisms were still unknown. In the present study, we found NEAT1 was expressed at high levels in docetaxel-resistant PCa clinical samples and related cell lines. When knockdown NEAT1, cell proliferation and invasion in docetaxel-resistant PCa cells in vitro and in vivo were downregulated. Our further researches explained that NEAT1 exerts oncogenic function in PCa by competitively ‘sponging’ both miR-34a-5p and miR-204-5p. Inhibition of miR-34a-5p or miR-204-5p expression mimics the docetaxel-resistant activity of NEAT1, whereas ectopic expression of miR-34a-5p or miR-204-5p attenuates the anti-drug function of NEAT1 in PCa cells. Besides, we also found ACSL4 is a target of both miR-34a-5p and miR-204-5p, and ACSL4 was also inhibited by miR-34a-5p and miR-204-5p. Moreover, suppression of miR-34a-5p or/and miR-204-5p greatly restrained the expression of ACSL4 upon NEAT1 overexpression. Joint expression of miR-34a-5p and miR-204a-5p synergistically decreased the expression of ASCL4, indicating miR-34a-5p and miR-204a-5p collaboratively inhibit the expression of ACSL4. Innovatively, we concluded that NEAT1 contributes to the docetaxel resistance by increasing ACSL4 via sponging miR-34a-5p and miR-204-5p in PCa cells.     

Characterization of tubule and monomer derived from VP4 protein of infectious bursal disease virus

The VP4 protein of infectious bursal disease virus (IBDV) is a serine protease that processes the polyprotein for viral assembly. VP4 has been found to associate primarily with type II IBDV tubules that are 24 nm in diameter. In this study, a chimeric VP4, assigned as HS1VP4, was constructed with a VP4-autocleavage site inserted between the N-terminal His-tag and the VP4 sequence. The results showed that the VP4 forms tubules after the self-cleavage of HS1VP4 when expressed in Escherichia coli. Furthermore, a deletion of 28 amino acids at the C-terminus of VP4 resulted in monomers and dimers instead of tubule formation; mutants of S652A and K692A at active site destroyed the activity. The endopeptidase activity of these monomers and dimers was approximately 12.5 times higher than that of VP4 tubules. Additionally, the formation of tubules inhibited VP4 protease activity, as demonstrated through in vitro assays. The production and characterization of monomers or dimers that have greater endopeptidase activity and protease activity than tubules can provide further insight into VP4 tubule assembly and the regulation of VP4 activity in host cells; this insight will facilitate the development of new anti-IBDV strategies.     

Estimation of extremely small field radiation dose for brain stereotactic radiotherapy using the Vero4DRT system

The purpose of this study was a dosimetric validation of the Vero4DRT for brain stereotactic radiotherapy (SRT) with extremely small fields calculated by the treatment planning system (TPS) iPlan (Ver.4.5.1; algorithm XVMC). Measured and calculated data (e.g. percentage depth dose [PDD], dose profile, and point dose) were compared for small square fields of 30 × 30, 20 × 20, 10 × 10 and 5 × 5 mm² using ionization chambers of 0.01 or 0.04 cm³ and a diamond detector. Dose verifications were performed using an ionization chamber and radiochromic film (EBT3; the equivalent field sizes used were 8.2, 8.7, 8.9, 9.5, and 12.9 mm²) for five brain SRT cases irradiated with dynamic conformal arcs.The PDDs and dose profiles for the measured and calculated data were in good agreement for fields larger than or equal to 10 × 10 mm² when an appropriate detector was chosen. The dose differences for point doses in fields of 30 × 30, 20 × 20, 10 × 10 and 5 × 5 mm² were +0.48%, +0.56%, −0.52%, and +11.2% respectively. In the dose verifications for the brain SRT plans, the mean dose difference between the calculated and measured doses were −0.35% (range, −0.94% to +0.47%), with the average pass rates for the gamma index under the 3%/2 mm criterion being 96.71%, 93.37%, and 97.58% for coronal, sagittal, and axial planes respectively.The Vero4DRT system provides accurate delivery of radiation dose for small fields larger than or equal to 10 × 10 mm².