Bioprosthetic heart valves (BHVs) are commonly used to replace severely diseased heart valves but their susceptibility to structural valve degeneration (SVD) limits their use in young patients. We hypothesized that antibodies against immunogenic glycans present on BHVs, particularly antibodies against the xenoantigens galactose-α1,3-galactose (αGal) and N-glycolylneuraminic acid (Neu5Gc), could mediate their deterioration through calcification. We established a large longitudinal prospective international cohort of patients (n = 1668, 34 ± 43 months of follow-up (0.1–182); 4,998 blood samples) to investigate the hemodynamics and immune responses associated with BHVs up to 15 years after aortic valve replacement. Early signs of SVD appeared in <5% of BHV recipients within 2 years. The levels of both anti-αGal and anti-Neu5Gc IgGs significantly increased one month after BHV implantation. The levels of these IgGs declined thereafter but anti-αGal IgG levels declined significantly faster in control patients compared to BHV recipients. Neu5Gc, anti-Neu5Gc IgG and complement deposition were found in calcified BHVs at much higher levels than in calcified native aortic valves. Moreover, in mice, anti-Neu5Gc antibodies were unable to promote calcium deposition on subcutaneously implanted BHV tissue engineered to lack αGal and Neu5Gc antigens. These results indicate that BHVs manufactured using donor tissues deficient in αGal and Neu5Gc could be less prone to immune-mediated deterioration and have improved durability.

Genetic sequencing should be used to confirm cases because purpura fulminans is a rare finding.

Aim:  Combination of immunomagnetic separation (IMS) and lateral flow device (LFD) assays for the development of a sensitive, rapid, on‐site methodology that enables concentration and detection of Bacillus anthracis spores in complex samples. Methods and Results:  The data presents the development of an optimized, 30 min, IMS assay, with about 95% capture of B. anthracis spores from different dairy products (n = 38). No cross reactivity was detected with typical milk flora and some closely related Bacilli. To enable direct application of the IMS captured spores on the LFD, spores were eluted from the bead–spore complex utilizing 95% (v/v) formamide‐10 mmol l−1 EDTA for 30 s in a microwave oven. Detached spores were analysed on LFD enabling detection within 10 min. The combined IMS–LFD methodology (40 min) demonstrates a 60‐fold improvement in sensitivity, relative to samples that were applied directly on the LFD without the IMS concentrating step. Conclusions:  The IMS–LFD method is a powerful platform, combining rapidity, specificity and efficiency for concentrating and detecting B. anthracis from water and milk contaminated samples. Significant and Impact of the Study:  The combination of IMS and LFD enhances the sensitivity and flexibility of B. anthracis spore detection from complex samples. This method can potentially be extended to other toxins and micro‐organisms in a variety of matrices.

Highlights The genetic identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is based on viral RNA extraction prior to RT-qPCR assay, however recent studies, using different buffers, support the elimination of the extraction step (direct approaches). We obtained similar limit of detection levels for SARS-CoV-2 when analyzing laboratory (non-clinical) samples using viral RNA extraction prior to RT-qPCR assay and direct approaches. However, in clinical oro-nasopharyngeal SARS-CoV-2 swabs, there was an advantage for the extraction procedure. Although previously reported to facilitate viral detection, the buffers tested here severely compromised the level of detection of clinical samples. A direct no-buffer approach might be an alternative, in times of need, since it identified more than 60% of positive clinical specimens.