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Nilsson, P.

Publications and source records attributed to Nilsson, P..

20 records · Page 2Linked to original sources

Rapid, specific detection and quantification of Yersinia pestis using a species-specific SNP in the ferric uptake regulator gene (furMAMA)

Yersinia pestis, the causative agent of plague, is responsible for about 700 human cases of bubonic and pneumonic plague each year. Yet the disease is far more prevalent within rodent reservoirs than in humans. One of the main means of outbreak prevention is extensive wildlife surveillance, where accurate and rapid detection is essential to prevent spillover into the human population from which, it may otherwise spread more rapidly and over larger distances. Moreover, detection and quantification of the agent aids in investigative studies to understand aspects of the pathogen such as transmission mechanics, pathology, contamination risk and more. Partially based on a previously developed assay by Gabitzsch et al. 2008 we designed a TaqMan(R) mismatch amplification mutation assay (TaqMAMA) where a primer leverages a species-specific SNP in the chromosomal single copy ferric uptake regulator gene of Yersinia pestis. The assay allows for specific, rapid detection and quantification of Yersinia pestis using only a single species-specific marker in a highly conserved virulence gene. This low-cost and simple modification of an existing assay eliminates the need for running multiple molecular markers for pathogen detection or performing time-consuming culturing and counting of colonies for quantification.

molecular biology↗

Mass spectrometry based qualification ofantibodies for plasma proteomics.

There is a strong need for procedures that enable context and application dependent validation of antibodies. Here we describe the foundation for a resource aiding more detailed assessment antibody selectivity for capturing endogenous proteins from human plasma. In 414 immunoprecipitation (IP) experiments with EDTA plasma, data was generated by mass spectrometry (LC-MS) with 157 antibodies (targeting 120 unique proteins). Out of a total of 1,313 unique proteins, 426 proteins (33%) were detected in > 20% of the assays and indicate a background comprised of mainly proteins from the complement system. For all proteins identified either in heat-treated or untreated EDTA plasma, frequencies of occurrence were derived. We determined z-scores for each IP as a measure of enrichment to annotate the antibodies into four categories (ON-target, CO-target, OFF-target and NO-target). For 45% (70/157) of the tested antibodies, the expected target proteins were enriched (z-score [≥]3) above background. There were 84% (59/70) of binders that co-enriched other proteins beside the intended target, either due to OFF-target binding or predicted interactions. Comparing several antibodies raised against IGFBP2, the established library allowed us to describe protein complexes in plasma, and we employed multiplexed sandwich immunoassays to confirm these. In summary, the generated resource of plasma enrichment profiles and background proteins adds a very useful and yet lacking starting point for the assessment of antibody selectivity in this clinically important body fluid. The provided insights will contribute to a more informed use of validated affinity reagents and may lead to further advancements of plasma proteomics assays.

biochemistry↗