During crime scene investigations, numerous traces are secured and may be used as evidence for the evaluation of source and/or activity level propositions. The rapid chemical analysis of a biological trace enables the identification of body fluids and can provide significant donor profiling information, including age, sex, drug abuse, and lifestyle. Such information can be used to provide new leads, exclude from, or restrict the list of possible suspects during the investigative phase. This paper reviews the state-of-the-art labelling techniques to identify the most suitable visual enhancer to be implemented in a lateral flow immunoassay setup for the purpose of trace identification and/or donor profiling. Upon comparison, and with reference to the strengths and limitations of each label, the simplistic one-step analysis of noncompetitive lateral flow immunoassay (LFA) together with the implementation of carbon nanoparticles (CNPs) as visual enhancers is proposed for a sensitive, accurate, and reproducible in situ trace analysis. This approach is versatile and stable over different environmental conditions and external stimuli. The findings of the present comparative analysis may have important implications for future forensic practice. The selection of an appropriate enhancer is crucial for a well-designed LFA that can be implemented at the crime scene for a time- and cost-efficient investigation.
Knowledge of the time of deposition is pivotal in forensic investigations. Recent studies show that changes in intrinsic fluorescence over time can be used to estimate the age of body fluids. These changes have been attributed to oxidative modifications caused by protein–lipid interactions. This pilot study aims to explore the impact of these modifications on body fluid fluorescence, enhancing the protein–lipid model system for age estimation. Lipid and protein oxidation markers, including protein carbonyls, dityrosine, advanced glycation end-products (AGEs), malondialdehyde (MDA), and 4-hydroxynonenal (HNE), were studied in aging semen, urine, and saliva over 21 days. Surface plasmon resonance imaging (SPRi), enzyme-linked immunosorbent assay (ELISA), and fluorescence spectroscopy were applied. Successful detection of AGE, dityrosine, MDA, and HNE occurred in semen and saliva via SPRi, while only dityrosine was detected in urine. Protein carbonyls were measured in all body fluids, but only in saliva was a significant increase observed over time. Additionally, protein fluorescence loss and fluorescent oxidation product formation were assessed, showing significant decreases in semen and saliva, but not in urine. Although optimization is needed for accurate quantification, this study reveals detectable markers for protein and lipid oxidation in aging body fluids, warranting further investigation.
MULTIFILE
From teh UU repository: "Background: Oral immunotherapy (OIT) is a promising therapeutic approach to treat food allergic patients. However, there are some concerns regarding its safety and long-term efficacy. The use of non-digestible oligosaccharides might improve OIT efficacy since they are known to directly modulate intestinal epithelial and immune cells in addition to acting as prebiotics. Aim: To investigate whether a diet supplemented with plant-derived fructo-oligosaccharides (FOS) supports the efficacy of OIT in a murine cow's milk allergy model and to elucidate the potential mechanisms involved. Methods: After oral sensitization to the cow's milk protein whey, female C3H/HeOuJ mice were fed either a control diet or a diet supplemented with FOS (1% w/w) and received OIT (10 mg whey) 5 days a week for 3 weeks by gavage. Intradermal (i.d.) and intragastric (i.g.) challenges were performed to measure acute allergic symptoms and mast cell degranulation. Blood and organs were collected to measure antibody levels and T cell and dendritic cell populations. Spleen-derived T cell fractions (whole spleen-and CD25-depleted) were transferred to naive recipient mice to confirm the involvement of regulatory T cells (Tregs) in allergy protection induced by OIT + FOS. Results: OIT + FOS decreased acute allergic symptoms and mast cell degranulation upon challenge and prevented the challenge-induced increase in whey-specific IgE as observed in sensitized mice. Early induction of Tregs in the mesenteric lymph nodes (MLN) of OIT + FOS mice coincided with reduced T cell responsiveness in splenocyte cultures. CD25 depletion in OIT + FOS-derived splenocyte suspensions prior to transfer abolished protection against signs of anaphylaxis in recipients. OIT + FOS increased serum galectin-9 levels. No differences in short-chain fatty acid (SCFA) levels in the cecum were observed between the treatment groups. Concisely, FOS supplementation significantly improved OIT in the acute allergic skin response, %Foxp3+ Tregs and %LAP+ Th3 cells in MLN, and serum galectin-9 levels. Conclusion: FOS supplementation improved the efficacy of OIT in cow's milk allergic mice. Increased levels of Tregs in the MLN and abolished protection against signs of anaphylaxis upon transfer of CD25-depleted cell fractions, suggest a role for Foxp3+ Tregs in the protective effect of OIT + FOS. "
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Pre-eclampsia (PE) is a common and severe pregnancy complication and is associated with substantial perinatal morbidity and mortality in mothers and infants. The disease is often characterized by a non-specific presentation which makes it challenging for physician to diagnose PE during regular pregnancy check-ups. To date, there are no diagnostic tests on the market for detection of PE early in pregnancy (first trimester). In this project, we will develop a platform to sensitively analyse calcium-binding proteins (CBPs) which will unlock the full potential of CBPs as predictive PE markers. The technology will also be applicable for other diseases (e.g., dementia and cancer) where CBPs are also known to play a key role in disease pathophysiology. We will develop with phage display antibodies that can recognize calcium binding to specific motifs in proteins. To this end we will synthesize peptide motifs with and without calcium to select antibodies that are specific for calcium bound proteins. These antibodies will be validated for their clinical use. For this goal we will use serum samples from the Improved studie (EU subsidised study) to determine if we can recognize pre-eclampsia in a very early stage. This knowledge can lead to a better treatment of pregnant women suffering from this disease and also will probably increase the well-being for the baby born and the development further in life.
The missing link in diagnostic testing for rheumatoid arthritis (RA) is an agglutination assay, easy to perform and dedicated to decentralized testing. Approximately 75% of RA patients produce autoantibodies to citrullinated proteins (ACPA), which can be detected using an agglutination-based diagnostic test. Such a diagnostic test will be cheaper, less laborious and faster than current tests and does not require sophisticated equipment. Novio Catalpa is developing this alternative test for ACPA in collaboration with Radboud University. To develop this test, specifically tagged and citrullinated nanobodies are needed, but the production is still challenging. Current methods for the production of ACPA diagnostics involve chemical synthesis, in which a variety of toxic chemicals are used in each step. The alternative assay involves nanobodies fused with RA-biomarker target entities, which can be completely produced by ‘green synthesis’ in the yeast Pichia pastoris using the expertise of HAN BioCentre. The yeast P. pastoris has proven to be able to produce nanobodies and is a fast and cost-effective platform that often results in high protein yields. Goal of the project is therefore to determine the feasibility and best green route to produce purified nanobodies tagged with citrullinated ACPA targets that can be used for developing an agglutination assay for RA. P. pastoris does not produce endogenous PAD enzymes which are needed for citrullination of the nanobodies in order to be able to use it in a RA agglutination test. Therefore, PAD enzymes from other sources need to be tested and applied. The project results will be directly used by Novio Catalpa to further develop the innovative test for RA. This project will contribute to and finally result in a single-step agglutination assay suitable for both point-of-care testing and automation in clinical laboratories.
Biotherapeutic medicines such as peptides, recombinant proteins, and monoclonal antibodies have successfully entered the market for treating or providing protection against chronic and life-threatening diseases. The number of relevant commercial products is rapidly increasing. Due to degradation in the gastro-intestinal tract, protein-based drugs cannot be taken orally but need to be administered via alternative routes. The parenteral injection is still the most widely applied administration route but therapy compliance of injection-based pharmacotherapies is a concern. Long-acting injectable (LAI) sustained release dosage forms such as microparticles allow less frequent injection to maintain plasma levels within their therapeutic window. Spider Silk Protein and Poly Lactic-co-Glycolic Acid (PLGA) have been attractive candidates to fabricate devices for drug delivery applications. However, conventional microencapsulation processes to manufacture microparticles encounter drawbacks such as protein activity loss, unacceptable residual organic solvents, complex processing, and difficult scale-up. Supercritical fluids (SCF), such as supercritical carbon dioxide (scCO2), have been used to produce protein-loaded microparticles and is advantageous over conventional methods regarding adjustable fluid properties, mild operating conditions, interfacial tensionless, cheap, non-toxicity, easy downstream processing and environment-friendly. Supercritical microfluidics (SCMF) depict the idea to combine strengths of process scale reduction with unique properties of SCF. Concerning the development of long-acting microparticles for biological therapeutics, SCMF processing offers several benefits over conventionally larger-scale systems such as enhanced control on fluid flow and other critical processing parameters such as pressure and temperature, easy modulation of product properties (such as particle size, morphology, and composition), cheaper equipment build-up, and convenient parallelization for high-throughput production. The objective of this project is to develop a mild microfluidic scCO2 based process for the production of long-acting injectable protein-loaded microparticles with, for example, Spider Silk Protein or PLGA as the encapsulating materials, and to evaluate the techno-economic potential of such SCMF technology for practical & industrial production.