Разработка алгоритмического и программного обеспечения для дозиметрического планирования курсов лучевой нейтронной терапии онкологических заболеваний

Выпускная квалификационная работа направлена на разработку и программную реализацию алгоритма, предназначенного для дозиметрического планирования лучевой нейтронной терапии онкологических заболеваний. В результате исследования были изучены алгоритмы расчета поглощенных доз нейтронов. Была разработана программа на основе изученных алгоритмов. Для визуализации распределения доз нейтронов была построена топографическая карта.The final qualification work is aimed at the development and software implementation of an algorithm designed for dosimetric planning of radiation neutron cancer therapy. As a result of the study, the algorithms for calculating the absorbed doses of neutrons were studied. The program was developed based on the studied algorithms. A topographic map was built to visualize the distribution of neutron doses

TGF-β inhibitor Smad7 regulates dendritic cell-induced autoimmunity

TGF-β is an anti-inflammatory cytokine whose signaling is negatively controlled by Smad7. Previously, we established a role for Smad7 in the generation of autoreactive T cells; however, the function of Smad7 in dendritic cells (DCs) remains elusive. Here, we demonstrate that DC-specific Smad7 deficiency resulted in elevated expression of the transcription factors Batf3 and IRF8, leading to increased frequencies of CD8(+)CD103(+) DCs in the spleen. Furthermore, Smad7-deficient DCs expressed higher levels of indoleamine 2,3-dioxygenase (IDO), an enzyme associated with tolerance induction. Mice devoid of Smad7 specifically in DCs are resistant to the development of experimental autoimmune encephalomyelitis (EAE) as a result of an increase of protective regulatory T cells (Tregs) and reduction of encephalitogenic effector T cells in the central nervous system. In agreement, inhibition of IDO activity or depletion of Tregs restored disease susceptibility. Intriguingly, when Smad7-deficient DCs also lacked the IFN-γ receptor, the mice regained susceptibility to EAE, demonstrating that IFN-γ signaling in DCs mediates their tolerogenic function. Our data indicate that Smad7 expression governs splenic DC subset differentiation and is critical for the promotion of their efficient function in immunity

Intralesional TLR4 agonist treatment strengthens the organ defense against colonizing cancer cells in the brain

Brain metastasis in breast cancer remains difficult to treat and its incidence is increasing. Therefore, the development of new therapies is of utmost clinical relevance. Recently, toll-like receptor (TLR) 4 was correlated with IL6 expression and poor prognosis in 1 215 breast cancer primaries. In contrast, we demonstrated that TLR4 stimulation reduces microglia-assisted breast cancer cell invasion. However, the expression, prognostic value, or therapeutic potential of TLR signaling in breast cancer brain metastasis have not been investigated. We thus tested the prognostic value of various TLRs in two brain-metastasis gene sets. Furthermore, we investigated different TLR agonists, as well as MyD88 and TRIF-deficient microenvironments in organotypic brain-slice ex vivo co-cultures and in vivo colonization experiments. These experiments underline the ambiguous roles of TLR4, its adapter MyD88, and the target nitric oxide (NO) during brain colonization. Moreover, analysis of the gene expression datasets of breast cancer brain metastasis patients revealed associations of TLR1 and IL6 with poor overall survival. Finally, our finding that a single LPS application at the onset of colonization shapes the later microglia/macrophage reaction at the macro-metastasis brain-parenchyma interface (MMPI) and reduces metastatic infiltration into the brain parenchyma may prove useful in immunotherapeutic considerations

T Cell-Dependence of Lassa Fever Pathogenesis

Lassa virus (LASV), the causative agent of Lassa fever (LF), is endemic in West Africa, accounting for substantial morbidity and mortality. In spite of ongoing research efforts, LF pathogenesis and mechanisms of LASV immune control remain poorly understood. While normal laboratory mice are resistant to LASV, we report that mice expressing humanized instead of murine MHC class I (MHC-I) failed to control LASV infection and develop severe LF. Infection of MHC-I knockout mice confirmed a key role for MHC-I-restricted T cell responses in controlling LASV. Intriguingly we found that T cell depletion in LASV-infected HHD mice prevented disease, irrespective of high-level viremia. Widespread activation of monocyte/macrophage lineage cells, manifest through inducible NO synthase expression, and elevated IL-12p40 serum levels indicated a systemic inflammatory condition. The absence of extensive monocyte/macrophage activation in T cell-depleted mice suggested that T cell responses contribute to deleterious innate inflammatory reactions and LF pathogenesis. Our observations in mice indicate a dual role for T cells, not only protecting from LASV, but also enhancing LF pathogenesis. The possibility of T cell-driven enhancement and immunopathogenesis should be given consideration in future LF vaccine development

Die Diversität TLR4-getriggerter Reaktionen in Mikroglia der Maus

Mikroglia repräsentieren den vorherrschenden Immunzelltyp im ZNS. Während der steten Überwachung der Mikroumgebung sind diese Zellen jederzeit bereit, vom ruhenden in einen aktivierten Status zu wechseln. Dies geschieht insbesondere nach dem aufspüren von "Gefahr"-assoziierten Signalen, wie dem plötzlichen Auftreten von bestimmten Faktoren, deren abnormaler Konzentration oder unregelmäßiger molekularer Konformation. Neben einer Vielzahl von Rezeptoren verwenden Mikroglia Toll-like Rezeptoren (TLRs), welche sowohl exogene als auch endogene "Gefahren" erkennen. Die Stimulation der mikroglialen TLRs resultiert in einer angeborenen Immunreaktion, welche den Schutz des ZNS sowie die Unterstützung von Reparaturprozessen an geschädigten Geweben zum Ziel hat. Innerhalb der TLR Familie nimmt der TLR4 eine besondere Stellung ein. Dies ist in erster Linie durch die duale Benutzung der beiden TLR Signalwegsassoziierten Adaptermoleküle MyD88 und TRIF gekennzeichnet. Die vorliegende Arbeit beschäftigte sich mit der mikroglialen Reaktion nach Stimulation mit bakteriellem LPS, dem prototypischen Agonisten des TLR4. Wir fanden heraus, dass die Zellen unterschiedlich auf strukturelle Varianten des LPS, stellvertretend für unterschiedliche Bakterienstämme, reagieren. In diesem Prozess zeigte der Korezeptor CD14 einen entscheidenden Einfluss. Weiterhin konnten wir zeigen, dass die Aktivierung mikroglialer TLRs und die daraus resultierenden Reaktionen hochkomplex organisiert sind und von der "Signalstärke" abhängen. Darüber hinaus stellten wir fest, dass diese mikroglialen Reaktionen durch sekundäre Signale sowohl immunologischen als auch nicht-immunologischen Ursprungs moduliert werden können. Schließlich konnten wir zeigen, dass sich der mikrogliale TLR(4)-Signalweg während der Entwicklung/Reifung des ZNS reorganisiert, und dass er ein individuelles Funktionsprofil in unterschiedlichen anatomischen Regionen und Populationen des ZNS annimmt. Zusammenfassend argumentieren diese Daten für die Vielseitigkeit des mikroglialen TLR4-Sign alwegs. Dabei ist dieser stark reguliert und (re)organisiert, was die speziellen Anforderungen des ZNS als Umgebung widerspiegelt

Proteomic analysis of stratum corneum in Cutaneous T-Cell Lymphomas and psoriasis

Stratum corneum collected by tape stripping from 10 and 24 subjects with cutaneous T-cell lymphomas (CTCL) or psoriasis, respectively, were compared using quantitative label-free mass spectrometry analysis. A non-supervised statistical analysis (Posneg NMF) based on 352 differentially expressed proteins in both CTCL and psoriasis samples was able to separate the two disease groups and finally able to identify a set of 112 proteins that contributed most and significantly to the separation when compared to non-lesional samples. In addition, Luminex assay revealed that the increase in the amount of chemokines related to the inflammatory response, and immune cell infiltration and recruitment in lesional stratum corneum in CTCL, including CXCL8, CXCL9, CXCL10, CCL27, TNF and sICAM-1 was in agreement with published data on entire skin biopsies. Proteome analysis using quantitative methods including mass spectrometry and Luminex technology offered the possibility to investigate the relevant protein signature in CTCL and may be helpful to diagnose and investigate the efficacy of treatments in clinical investigations using non-invasive methods in future

Manipulation of host hepatocytes by the malaria parasite for delivery into liver sinusoids

The merozoite stage of the malaria parasite that infects erythrocytes and causes the symptoms of the disease is initially formed inside host hepatocytes. However, the mechanism by which hepatic merozoites reach blood vessels (sinusoids) in the liver and escape the host immune system before invading erythrocytes remains unknown. Here, we show that parasites induce the death and the detachment of their host hepatocytes, followed by the budding of parasite-filled vesicles (merosomes) into the sinusoid lumen. Parasites simultaneously inhibit the exposure of phosphatidylserine on the outer leaflet of host plasma membranes, which act as eat me'' signals to phagocytes. Thus, the hepatocyte-derived merosomes appear to ensure both the migration of parasites into the bloodstream and their protection from host immunity.Bernhard Nocht Inst Trop Med, D-20359 Hamburg, GermanyInst Pasteur, Dept Parasitol, F-75724 Paris 15, FranceUniversidade Federal de São Paulo, Dept Biochem, BR-04044020 São Paulo, BrazilUniv Hamburg, Hosp Eppendorf, Dept Hepatobiliary Surg, D-20246 Hamburg, GermanyUniversidade Federal de São Paulo, Dept Biochem, BR-04044020 São Paulo, BrazilWeb of Scienc