33 research outputs found
The Effect of spatial separation in distance on the intelligibility of speech in rooms
The influence of spatial separation in source distance on speech reception thresholds (SRTs) is investigated. In one scenario, the target was presented at 0.5 m distance, and the masker varied from 0.5 m distance up to 10 m. In a second scenario, the masker was presented at 0.5 m distance and the target distance varied. The stimuli were synthesized using convolution with binaural room impulse responses (BRIRs) measured on a dummy head in a reverberant auditorium, and were equalized to compensate for distance-dependent spectral and intensity changes. All sources were simulated directly in front of the listener. SRTs decreased monotonically when the target was at 0.5 m and the speech-masker was moved further away, resulting in a SRT improvement of up to 10 dB. When the speech masker was at 0.5 m and the target was moved away, a large variation across subjects was observed. Neither short-term signal-to-noise ratio (SNR) improvements nor cross-ear glimpsing could account for the observed improvement in intelligibility. However, the effect might be explained by an improvement in the SNR in the modulation domain and a decrease in informational masking. This study demonstrates that distance-related cues can play a significant role when listening in complex environments.11 page(s
Vorbereitung des Uebergangs koerperbehinderter Jugendlicher von der Schule ins Arbeitsleben Forschungsprojekt 1.5.1990 bis 30.11.1994
IAB-96-520-53 BC 701 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman
Anti-CD28 mAb increase the induction of CD2 mediated apoptosis of lamina propria T lymphocytes in vivo
CAR T Cells with Enhanced Sensitivity to B Cell Maturation Antigen for the Targeting of B Cell Non-Hodgkin's Lymphoma and Multiple Myeloma
Autologous T cells genetically modified with a chimeric antigen receptor (CAR) redirected at CD19 have potent activity in the treatment of B cell leukemia and B cell non-Hodgkin's lymphoma (B-NHL). Immunotherapies to treat multiple myeloma (MM) targeted the B cell maturation antigen (BCMA), which is expressed in most cases of MM. We developed a humanized CAR with specificity for BCMA based on our previously generated anti-BCMA monoclonal antibody. The targeting single chain variable fragment (scFv) domain exhibited a binding affinity in the low nanomolar range, conferring T cells with high functional avidity. Redirecting T cells by this CAR allowed us to explore BCMA as an alternative target for mature B-NHLs. We validated BCMA expression in diffuse large B cell lymphoma, follicular lymphoma, mantle cell lymphoma, and chronic lymphocytic leukemia. BCMA CAR T cells triggered target cell lysis with an activation threshold in the range of 100 BCMA molecules, which allowed for an efficient eradication of B-NHL cells in vitro and in vivo. Our data corroborate BCMA is a suitable target in B cell tumors beyond MM, providing a novel therapeutic option for patients where BCMA is expressed at low abundance or where anti-CD19 immunotherapies have failed due to antigen loss
An NK Cell Perforin Response Elicited via IL-18 Controls Mucosal Inflammation Kinetics during Salmonella Gut Infection
Salmonella Typhimurium (S. Tm) is a common cause of self-limiting diarrhea. The mucosal inflammation is thought to arise from a standoff between the pathogen's virulence factors and the host's mucosal innate immune defenses, particularly the mucosal NAIP/NLRC4 inflammasome. However, it had remained unclear how this switches the gut from homeostasis to inflammation. This was studied using the streptomycin mouse model. S. Tm infections in knockout mice, cytokine inhibition and -injection experiments revealed that caspase-1 (not -11) dependent IL-18 is pivotal for inducing acute inflammation. IL-18 boosted NK cell chemoattractants and enhanced the NK cells' migratory capacity, thus promoting mucosal accumulation of mature, activated NK cells. NK cell depletion and Prf(-/-) ablation (but not granulocyte-depletion or T-cell deficiency) delayed tissue inflammation. Our data suggest an NK cell perforin response as one limiting factor in mounting gut mucosal inflammation. Thus, IL-18-elicited NK cell perforin responses seem to be critical for coordinating mucosal inflammation during early infection, when S. Tm strongly relies on virulence factors detectable by the inflammasome. This may have broad relevance for mucosal defense against microbial pathogens
CXCR5 CAR-T cells simultaneously target B cell non-Hodgkin's lymphoma and tumor-supportive follicular T helper cells
CAR-T cell therapy targeting CD19 demonstrated strong activity against advanced B cell leukemia, however shows less efficacy against lymphoma with nodal dissemination. To target both B cell Non-Hodgkin's lymphoma (B-NHLs) and follicular T helper (Tfh) cells in the tumor microenvironment (TME), we apply here a chimeric antigen receptor (CAR) that recognizes human CXCR5 with high avidity. CXCR5, physiologically expressed on mature B and Tfh cells, is also highly expressed on nodal B-NHLs. Anti-CXCR5 CAR-T cells eradicate B-NHL cells and lymphoma-supportive Tfh cells more potently than CD19 CAR-T cells in vitro, and they efficiently inhibit lymphoma growth in a murine xenograft model. Administration of anti-murine CXCR5 CAR-T cells in syngeneic mice specifically depletes endogenous and malignant B and Tfh cells without unexpected on-target/off-tumor effects. Collectively, anti-CXCR5 CAR-T cells provide a promising treatment strategy for nodal B-NHLs through the simultaneous elimination of lymphoma B cells and Tfh cells of the tumor-supporting TME. CAR-T cell therapy targeting CD19 is not as efficient to treat lymphoma with nodal dissemination as it is for B cell leukaemia. Here, the authors generate CAR-T cells against CXCR5 and show they inhibit tumour growth by depleting both B and follicular T helper cells in lymphoma models
Mesenchymal stromal cells but not cardiac fibroblasts exert beneficial systemic immunomodulatory effects in experimental myocarditis.
Systemic application of mesenchymal stromal cells (MSCs) in inflammatory cardiomyopathy exerts cardiobeneficial effects. The mode of action is unclear since a sufficient and long-acting cardiac homing of MSCs is unlikely. We therefore investigated the regulation of the immune response in coxsackievirus B3 (CVB3)-induced acute myocarditis after intravenous application of MSCs. Wildtype mice were infected with CVB3 and treated with either PBS, human MSCs or human cardiac fibroblasts intravenously 1 day after infection. Seven days after infection, MSCs could be detected in the spleen, heart, pancreas, liver, lung and kidney, whereby the highest presence was observed in the lung. MSCs increased significantly the myocardial expression of HGF and decreased the expression of the proinflammatory cytokines TNFα, IL1β and IL6 as well as the severity of myocarditis and ameliorated the left ventricular dysfunction measured by conductance catheter. MSCs upregulated the production of IFNγ in CD4+ and CD8+ cells, the number of IL10-producing regulatory T cells and the apoptosis rate of T cells in the spleen. An increased number of CD4+CD25+FoxP3 could be found in the spleen as well as in the circulation. In contrast, application of human cardiac fibroblasts had no effect on the severity of myocarditis and the systemic immune response observed after MSCs-administration. In conclusion, modulation of the immune response in extracardiac organs is associated with cardiobeneficial effects in experimental inflammatory cardiomyopathy after systemic application of MSCs