184 research outputs found
Priming App Information Privacy Concerns in Mobile Ecosystems
In the course of experiential computing privacy is entering personal space. Due to the implementation of all kinds of sensors and computing in everyday life of users, their privacy is at high risk. The high risk of privacy is strengthened by the classification of mobile app download decisions in mobile ecosystems as low effort processes. The article follows the call of Dinev et al. (2015) to investigate the influences of behavioral economics on privacy decisions. The paper provides the development of an app information privacy concern and six independent experiments in the field of priming information privacy with altogether 1954 participants. The results support the assumption of app decision-making as low effort process and indicate the influence of priming on individuals' information privacy concerns. This research contributes to increasing importance of understanding individuals' behavior in digital ecosystems
App Information Privacy Concerns
Due to the new technological developments and solutions a new user of information systems evolved. Smart Mobile Devices (SMD) and software in form of mobile applications (apps) diffused into the everyday life of users. The download and usage of apps became ubiquitous and by giving away personal data while using apps, individuals put their privacy at risk. Privacy concerns are generally used to measure information privacy. However, privacy is highly context dependent and needs to be adapted to the investigated environment. Therefore, the authors developed a measurement for app information privacy concerns (AIPC), based on existing literature. A data set of 269 participants was analyzed. For the AIPC three first-order dimensions (anxiety, personal attitude, and requirements) were revealed
Anomalous Immunogenic Properties of Serine Proteases
It has previously been shown that a similar to 27 kDa serine protease of Schistosoma mansoni larvae, the cercarial elastase (CE), was a poor immunogen in as much as it failed to induce an antibody response. The CE has a critical role in enabling schistosome larvae to penetrate the skin of their definitive hosts, so the apparently poor immunogenicity of this enzyme is clearly of interest. To understand its lack of immunogenicity better and in particular to determine whether it is related to its proteolytic activity, we have measured antibody responses of mice to three different serine proteases. Groups of mice were immunized with porcine pancreatic trypsin (TRY), chymotrypsin (CHY) or elastase (ELA) and the resulting antibody response compared with antibody responses to two non-protease antigens, chicken egg albumin (OVA) and Schistosoma japonicum glutathione S-transferase (GST), all being administered with alum as an adjuvant. Of 12 mice that were injected five times at 14 day intervals with TRY, only one produced antibody reactive with this enzyme in ELISA. Immunizations with CHY or ELA induced somewhat better antibody responses than TRY, but the responses to the first and second injections of these two proteases nevertheless seemed comparatively lower than the responses to GST. Induction of antibody responses by OVA and GST was not affected when TRY was injected concomitantly. Thus, the antibody response to one of the serine proteases used in this study, mammalian trypsin, was anomalous
An Experiment Series on App Information Privacy Concerns
The diffusion of smart mobile devices and therewith apps into everyday life comes along with the permanent disclosure of sensitive and personal data. Despite the concerns individuals have regarding their information privacy, they act oppositional. However, through the permanent disclosure of sensitive and personal information, privacy of individuals is at risk. The risk of privacy is intensified by the classification of the mobile app download and the usage decision processing as low effort processes without much deliberation. Therefore, the article follows the call of Dinev et al. (2015) to consider principles from behavioural economics and social psychology to investigate its influences on privacy decisions. This is operationalised with six independent experiments to examine the influence of cognitive biases on app information privacy concerns. The results support the underlying assumption of app decision-making as a low effort process and confirmed that different stimuli do influence privacy concerns of individuals. This research contributes to the increasing importance of understanding individ-uals’ behaviour in digital ecosystems
A new role for complement C3: regulation of antigen processing through an inhibitory activity.
International audienceIncreasing evidence underlines the involvement of complement component C3 in the establishment of acquired immunity which appears to play a complex role and to act at different levels. As antigen proteolysis by antigen presenting cells is a key event in the control of antigen presentation efficiency, and consequently in the quality of the immune response, we investigated whether C3 could modulate this step. Our results demonstrate for the first time that C3 can interfere with antigen proteolysis: (i) proteolysis of tetanus toxin (TT) by the lysosomal fraction from a human monocytic cell line (U937) is impaired in the presence of C3, (ii) this effect is C3-specific and involves the C3c fragment of the protein, (iii) C3c is effective even after disulfide disruption, but none of its three constitutive peptides is individually accountable for this inhibitory effect and (iv) the target-protease(s) exhibit(s) a serine-protease activity. The physiological relevance of our results is demonstrated by experiments showing a subcellular colocalisation of TT and C3 after their uptake by U937 and the reduction of TT proteolysis once internalised together with C3. These results highlight a novel role for C3 that broadens its capacity to modulate acquired immune response
Human cytomegalovirus infection of langerhans-type dendritic cells does not require the presence of the gH/gL/UL128-131A complex and is blocked after nuclear deposition of viral genomes in immature cells
Human cytomegalovirus (CMV) enters its host via the oral and genital mucosae. Langerhans-type dendritic cells (LC) are the most abundant innate immune cells at these sites, where they constitute a first line of defense against a variety of pathogens. We previously showed that immature LC (iLC) are remarkably resistant to CMV infection, while mature LC (mLC) are more permissive, particularly when exposed to clinical-strain-like strains of CMV, which display a pentameric complex consisting of the viral glycoproteins gH, gL, UL128, UL130, and UL131A on their envelope. This complex was recently shown to be required for the infection of immature monocyte-derived dendritic cells. We thus sought to establish if the presence of this complex is also necessary for virion penetration of LC and if defects in entry might be the source of iLC resistance to CMV. Here we report that the efficiency of LC infection is reduced, but not completely abolished, in the absence of the pentameric complex. While virion penetration and nuclear deposition of viral genomes are not impaired in iLC, the transcription of the viral immediate early genes UL122 and UL123 and of the delayed early gene UL50 is substantially lower than that in mLC. Together, these data show that the UL128, UL130, and UL131A proteins are dispensable for CMV entry into LC and that progression of the viral cycle in iLC is restricted at the step of viral gene expression
CK1δ in lymphoma: gene expression and mutation analyses and validation of CK1δ kinase activity for therapeutic application
The prognosis of lymphoid neoplasms has improved considerably during the last decades. However, treatment response for some lymphoid neoplasms is still poor, indicating the need for new therapeutic approaches. One promising new strategy is the inhibition of kinases regulating key signal transduction pathways, which are of central importance in tumorigenesis. Kinases of the CK1 family may represent an attractive drug target since CK1 expression and/or activity are associated with the pathogenesis of malignant diseases. Over the last years efforts were taken to develop highly potent and selective CK1-specific inhibitor compounds and their therapeutic potential has now to be proved in pre-clinical trials. Therefore, we analyzed expression and mutational status of CK1δ in several cell lines representing established lymphoma entities, and also measured the mRNA expression level in primary lymphoma tissue as well as in non-neoplastic blood cells. For a selection of lymphoma cell lines we furthermore determined CK1δ kinase activity and demonstrated therapeutic potential of CK1-specific inhibitors as a putative therapeutic option in the treatment of lymphoid neoplasm
VARIATION OF PROTEOLYTIC CLEAVAGE SITES TOWARDS THE N-TERMINAL END OF THE S2 SUBUNIT OF THE NOVEL SARS-COV-2 OMICRON SUBLINEAGE BA.2.12.1
The prevalence of novel SARS-CoV-2 variants is also accompanied by an increased turnover
rate and additional cleavage sites at the positions necessary for priming the Spike (S) protein. Of
these priming sites, the proteolytically sensitive polybasic sequence of the activation loop at the
S1/S2 interface and the S20 location within the S2 subunit of the S protein are cleaved by furin and
TMPRSS2, which are important for the infection of the target cell. Neutrophils, migrating to the site
of infection, secrete serine proteases to fight against pathogens. The serine proteases encompass
neutrophil elastase (NE), proteinase 3 (PR3), and cathepsin G (CatG), which can hydrolyze the peptide
bond adjacent to the S1/S2 interface. SARS-CoV-2 might take the opportunity to hijack proteases
from an immune response to support viral entry to the cell. The region near S704L within the S2
subunit, a novel amino acid substitution of SARS-CoV-2 Omicron sublineage BA.2.12.1, is located
close to the S1/S2 interface. We found that NE, PR3, and CatG digested the peptide within this
region; however, the S704L amino acid substitution altered cleavage sites for PR3. In conclusion,
such an amino acid substitution modifies S2 antigen processing and might further impact the major
histocompatibility complex (MHC) binding and T cell activation
Design of protease-resistant myelin basic protein-derived peptides by cleavage site directed amino acid substitutions
Multiple Sclerosis (MS) is considered to be a T cell-mediated autoimmune disease. An attractive strategy to prevent activation of autoaggressive T cells in MS, is the use of altered peptide ligands (APL), which bind to major histocompatibility complex class II (MHC II) molecules. To be of clinical use, APL must be capable of resisting hostile environments including the proteolytic machinery of antigen presenting cells (APC). The current design of APL relies on cost- and labour-intensive strategies. To overcome these major drawbacks, we used a deductive approach which involved modifying proteolytic cleavage sites in APL. Cleavage site-directed amino acid substitution of the autoantigen myelin basic protein (MBP) resulted in lysosomal protease-resistant, high-affinity binding peptides. In addition, these peptides mitigated T cell activation in a similar fashion as conventional APL. The strategy outlined allows the development of protease-resistant APL and provides a universal design strategy to improve peptide-based immunotherapeutics
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