Immunoadsorption as a method of antibody donation during the COVID-19 pandemic.

BACKGROUND AND OBJECTIVES: Initial therapeutic efforts to treat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) included the use of plasma from convalescent donors containing anti-SARS-CoV-2 antibodies. High-neutralizing antibody titres are required for therapeutic efficacy. This study aims to show that immunoadsorption followed by tangential flow filtration can be used to obtain antibody concentrates with high-neutralizing capacities. MATERIALS AND METHODS: Eligible donors (n = 10, five males and three females) underwent immunoadsorption using adsorber columns specific for human antibodies. Glycine-washed out eluates of 1.5 L volume were further concentrated by tangential flow filtration using 30 kDa ultrafiltration membranes. The same membranes were applied for diafiltrations to exchange residual glycine for 0.9% normal saline. RESULTS: Antibody concentrates were obtained within 8 h from the start of donation and had, 4.58 ± 1.95, 3.28 ± 1.28 and 2.02 ± 0.92 times higher total IgG, IgA and IgM concentrations, 3.29 ± 1.62 and 3.74 ± 0.6 times higher SARS-CoV-2 N and S antibody concentrations and 3.85 ± 1.71 times higher SARS-CoV-2 S-specific IgG concentrations compared to the donors' peripheral blood. The specific SARS-CoV-2 virus neutralization capacities increased in all but one concentrate. All antibody concentrates (50-70 mL final volume) passed microbiological tests, were free of hazardous glycine levels and could be stored at -80°C and 4°C for 1 year with 20 ± 3% antibody loss. CONCLUSION: Immunoadsorption followed by tangential flow filtration is a feasible procedure to collect IgG, IgA and IgM as well as SARS-CoV-2 N- and S-specific antibody concentrates of low volume, free of albumin and coagulation factors. Whether these concentrates can be used as passive immunisation in infected patients remains to be elucidated.

New suture probe canaloplasty combined with suprachoroidal collagen implantation.

PURPOSE: To present the modified surgery technique of new suture probe canaloplasty with a specially prepared monofilament 4.0 polypropylene suture combined with suprachoroidal drainage (ScD) and collagen sheet implantation for non-penetrating glaucoma surgery. METHODS: Prospective study with a twelve months follow-up. A standard 4/0 polypropylene suture (ProleneTM by Ethicon; thickness: approximately 250 m) is cut and shaped with an ophthalmic knife (MANI® Crescent Knife, Mani Inc 8-3 Kiyohara Industrial Park, Utsunomiya, Tochigi 321-3231, Japan) to create a blunt end without sharp or compressed edges. This improves suture probe canaloplasty by providing a more stable and smoother probing device. Schlemm's canal is prepared using the standard technique of canaloplasty with suprachoroidal drainage. Then, instead of using the canaloplasty microcatheter or the previously published 6/0 double-helix suture, Schlemm's canal is probed with the blunt ending of the 4/0 Prolene suture. After successful 360-degree probing, a doubled 10/0 polypropylene tension suture is threaded through the tip of the 4/0 suture. The 4/0 suture is then pulled back and the 10/0 tension sutures are tied at both ends to tension Schlemm's canal. A special collagen sheet (Ologen®) is placed in suprachoroidal space, and the scleral flap is firmly sewed. RESULTS: 115 eyes were included in this prospective study. In 113 cases the Schlemm's canal could completely be probed with the suture probe and canaloplasty with ScD and collagen sheet implantation succeeded. In two cases the intervention was transformed to 360-degree suture trabeculotomy due to an intraoperative cheese-wiring. Twelve months after successful new suture probe canaloplasty with ScD and Collagen Implantation the IOP had decreased by 37.1% (from 21.6 ± 6.0 mmHg with 3.3 different IOP lowering eye drops to 13.5 ± 3.5 mmHg with 1.0 eye drops). 16 Patients did not achieve sufficient IOP levels and underwent 360-degree suture trabeculotomy during the follow-up. One patient had to be treated with further glaucoma surgery to achieve a sufficient IOP level. Complications were hyphema, postoperative IOP elevation and transient hypotony. No serious or sight-threatening complications occurred. CONCLUSION: New suture probe canaloplasty with ScD and collagen sheet implantation yields the opportunity to conduct a cost-effective canaloplasty easier and less complicated than with the previously described method with the twisted 6/0 suture. The safety profile and IOP lowering effect is comparable. In cases where complete probing fails, there is still the opportunity to switch to suture trabeculotomy over the majorly probed part of Schlemm's canal. The pressure lowering effect of the deep sclerectomy with ScD and suprachoroidal collagen sheet implant seems to have an additional impact on the sufficient pressure lowering procedure.

Screening for Primary Aldosteronism by Mass Spectrometry Versus Immunoassay Measurements of Aldosterone: A Prospective Within-Patient Study.

BACKGROUND: Measurements of aldosterone by mass spectrometry are more accurate and less prone to interferences than immunoassay measurements, and may produce a more accurate aldosterone:renin ratio (ARR) when screening for primary aldosteronism (PA). METHODS: Differences in diagnostic performance of the ARR using mass spectrometry vs immunoassay measurements of aldosterone were examined in 710 patients screened for PA. PA was confirmed in 153 patients and excluded in 451 others. Disease classifications were not achieved in 106 patients. Areas under receiver-operating characteristic curves (AUROC) and other measures were used to compare diagnostic performance. RESULTS: Mass spectrometry-based measurements yielded lower plasma aldosterone concentrations than immunoassay measurements. For the ARR based on immunoassay measurements of aldosterone, AUROCs were slightly lower (P = 0.018) than those using mass spectrometry measurements (0.895 vs 0.906). The cutoff for the ARR to reach a sensitivity of 95% was 30 and 21.5 pmol/mU by respective immunoassay and mass spectrometry-based measurements, which corresponded to specificities of 57% for both. With data restricted to patients with unilateral PA, diagnostic sensitivities of 94% with specificities >81% could be achieved at cutoffs of 61 and 52 pmol/mU for respective immunoassay and mass spectrometry measurements. CONCLUSIONS: Mass spectrometry-based measurements of aldosterone for the ARR provide no clear diagnostic advantage over immunoassay-based measurements. Both approaches offer limited diagnostic accuracy for the ARR as a screening test. One solution is to employ the higher cutoffs to triage patients likely to have unilateral PA for further tests and possible adrenalectomy, while using the lower cutoffs to identify others for targeted medical therapy.German Clinical Trials Register ID: DRKS00017084.

High-Affinity-Mediated Viral Entry Triggers Innate Affinity Escape Resulting in Type I IFN Resistance and Impaired T Cell Immunity.

Increased receptor binding affinity may allow viruses to escape from Ab-mediated inhibition. However, how high-affinity receptor binding affects innate immune escape and T cell function is poorly understood. In this study, we used the lymphocytic choriomeningitis virus (LCMV) murine infection model system to create a mutated LCMV exhibiting higher affinity for the entry receptor α-dystroglycan (LCMV-GPH155Y). We show that high-affinity receptor binding results in increased viral entry, which is associated with type I IFN (IFN-I) resistance, whereas initial innate immune activation was not impaired during high-affinity virus infection in mice. Consequently, IFN-I resistance led to defective antiviral T cell immunity, reduced type II IFN, and prolonged viral replication in this murine model system. Taken together, we show that high-affinity receptor binding of viruses can trigger innate affinity escape including resistance to IFN-I resulting in prolonged viral replication.

MMR vaccination induces trained immunity via functional and metabolic reprogramming of γδ T cells.

The measles, mumps, and rubella (MMR) vaccine protects against all-cause mortality in children, but the immunological mechanisms mediating these effects are poorly known. We systematically investigated whether MMR can induce long-term functional changes in innate immune cells, a process termed trained immunity, that could at least partially mediate this heterologous protection. In a randomized, placebo-controlled trial, 39 healthy adults received either the MMR vaccine or a placebo. Using single-cell RNA-Seq, we found that MMR caused transcriptomic changes in CD14+ monocytes and NK cells, but most profoundly in γδ T cells. Monocyte function was not altered by MMR vaccination. In contrast, the function of γδ T cells was markedly enhanced by MMR vaccination, with higher production of TNF and IFN-γ, as well as upregulation of cellular metabolic pathways. In conclusion, we describe a trained immunity program characterized by modulation of γδ T cell function induced by MMR vaccination.

Cisplatin-induced DNA crosslinks trigger neurotoxicity in C. elegans.

The anticancer drug cisplatin (CisPt) injures post-mitotic neuronal cells, leading to neuropathy. Furthermore, CisPt triggers cell death in replicating cells. Here, we aim to unravel the relevance of different types of CisPt-induced DNA lesions for evoking neurotoxicity. To this end, we comparatively analyzed wild-type and loss of function mutants of C. elegans lacking key players of specific DNA repair pathways. Deficiency in ercc-1, which is essential for nucleotide excision repair (NER) and interstrand crosslink (ICL) repair, revealed the most pronounced enhancement in CisPt-induced neurotoxicity with respect to the functionality of post-mitotic chemosensory AWA neurons, without inducing neuronal cell death. Potentiation of CisPt-triggered neurotoxicity in ercc-1 mutants was accompanied by complex alterations in both basal and CisPt-stimulated mRNA expression of genes involved in the regulation of neurotransmission, including cat-4, tph-1, mod-1, glr-1, unc-30 and eat-18. Moreover, xpf-1, csb-1, csb-1;xpc-1 and msh-6 mutants were significantly more sensitive to CisPt-induced neurotoxicity than the wild-type, whereas xpc-1, msh-2, brc-1 and dog-1 mutants did not distinguish from the wild-type. The majority of DNA repair mutants also revealed increased basal germline apoptosis, which was analyzed for control. Yet, only xpc-1, xpc-1;csb-1 and dog-1 mutants showed elevated apoptosis in the germline following CisPt treatment. To conclude, we provide evidence that neurotoxicity, including sensory neurotoxicity, is triggered by CisPt-induced DNA intra- and interstrand crosslinks that are subject of repair by NER and ICL repair. We hypothesize that especially ERCC1/XPF, CSB and MSH6-related DNA repair protects from chemotherapy-induced neuropathy in the context of CisPt-based anticancer therapy.

The oral sensory organs in Bathochordaeus stygius (Tunicata Appendicularia) are unique in structure and homologous to the coronal organ.

BACKGROUND: Appendicularia consists of approximately 70 purely marine species that belong to Tunicata the probable sister taxon to Craniota. Therefore, Appendicularia plays a pivotal role for our understanding of chordate evolution. In addition, appendicularians are an important part of the epipelagic marine plankton. Nevertheless, little is known about appendicularian species, especially from deeper water. RESULTS: Using µCT, scanning electron microscopy, and digital 3D-reconstruction techniques we describe three pairs of complex oral sensory organs in the mesopelagic appendicularian Bathochordaeus stygius. The oral sensory organs are situated at the anterior and lateral margin of the mouth and inside the mouth cavity. A single organ consists of 22-90 secondary receptor cells that project apical cilia through a narrow hole in the epidermis. The receptor cells are innervated by branches of the second brain nerve. CONCLUSIONS: Based on position, morphology, and innervation we suggest that the oral sensory organs are homologues of the coronal organs in other tunicates. We discuss the hypothesized homology of coronal organs and the lateral line system of primary aquatic vertebrates. The complex oral sensory organs of B. stygius are unique in tunicates and could be adaptations to the more muffled environment of the mesopelagic.

Srsf1 and Elavl1 act antagonistically on neuronal fate choice in the developing neocortex by controlling TrkC receptor isoform expression.

The seat of higher-order cognitive abilities in mammals, the neocortex, is a complex structure, organized in several layers. The different subtypes of principal neurons are distributed in precise ratios and at specific positions in these layers and are generated by the same neural progenitor cells (NPCs), steered by a spatially and temporally specified combination of molecular cues that are incompletely understood. Recently, we discovered that an alternatively spliced isoform of the TrkC receptor lacking the kinase domain, TrkC-T1, is a determinant of the corticofugal projection neuron (CFuPN) fate. Here, we show that the finely tuned balance between TrkC-T1 and the better known, kinase domain-containing isoform, TrkC-TK+, is cell type-specific in the developing cortex and established through the antagonistic actions of two RNA-binding proteins, Srsf1 and Elavl1. Moreover, our data show that Srsf1 promotes the CFuPN fate and Elavl1 promotes the callosal projection neuron (CPN) fate in vivo via regulating the distinct ratios of TrkC-T1 to TrkC-TK+. Taken together, we connect spatio-temporal expression of Srsf1 and Elavl1 in the developing neocortex with the regulation of TrkC alternative splicing and transcript stability and neuronal fate choice, thus adding to the mechanistic and functional understanding of alternative splicing in vivo.

The impact of BNT162b2 mRNA vaccine on adaptive and innate immune responses.

The mRNA-based BNT162b2 protects against severe disease and mortality caused by SARS-CoV-2 via induction of specific antibody and T-cell responses. Much less is known about its broad effects on immune responses against other pathogens. Here, we investigated the adaptive immune responses induced by BNT162b2 vaccination against various SARS-CoV-2 variants and its effects on the responsiveness of immune cells upon stimulation with heterologous stimuli. BNT162b2 vaccination induced effective humoral and cellular immunity against SARS-CoV-2 that started to wane after six months. We also observed long-term transcriptional changes in immune cells after vaccination. Additionally, vaccination with BNT162b2 modulated innate immune responses as measured by inflammatory cytokine production after stimulation - higher IL-1/IL-6 release and decreased IFN-α production. Altogether, these data expand our knowledge regarding the overall immunological effects of this new class of vaccines and underline the need for additional studies to elucidate their effects on both innate and adaptive immune responses.

MORTALITY, SURVIVAL, AND SEROLOGIC RESULTS FOR ELK (CERVUS CANADENSIS) IN THE CUMBERLAND MOUNTAINS OF TENNESSEE, USA.

Comprehensive disease surveillance has not been conducted in elk (Cervus canadensis) in Tennessee, US, since their reintroduction to the state 20 yr ago. We identified causes of death, estimated annual survival, and identified pathogens of concern in elk at the North Cumberland Wildlife Management Area (NCWMA), Tennessee, US. In 2019 and 2020, we captured 29 elk (21 females, eight males) using chemical immobilization and fitted individuals with GPS collars with mortality sensors. Elk that died between February 2019 and February 2022 were necropsied to identify causes of death; these included disease associated with meningeal worm (Parelaphostrongylus tenuis; n=3), poaching (n=1), vehicular collision (n=1), legal hunter harvest (n=1), and unknown due to carcass degradation (n=3). Using data from GPS collars and known-fate survival models, we estimated an average yearly survival rate of 80.2%, indicating that survival had not significantly increased from soon after elk reintroduction (79.9%). We collected blood, tissue, feces, and ectoparasites opportunistically from anesthetized elk for health surveillance. We identified lone star ticks (Amblyomma americanum; n=53, 85.5%; 95% confidence interval [CI], 73.72-92.75), American dog ticks (Dermacentor variabilis; n=8, 12.9%; 95% CI, 6.13-24.40), and black-legged ticks (Ixodes scapularis; n=1, 1.6%; 95% CI, 0.08-9.83). We detected evidence of exposure to Anaplasma marginale (100%; 95% CI, 84.50-100.00), Leptospira interrogans (70.4%; 95% CI, 49.66-85.50), Toxoplasma gondii (55.6%; 95% CI, 35.64-73.96), epizootic hemorrhagic disease virus (51.9%; 95% CI, 32.35-70.84), and Theileria cervi (25.9%; 95% CI, 11.78-46.59). Johne's disease (Mycobacterium avium subsp. paratuberculosis) is potentially established within the population, but has not been previously documented in eastern elk populations. Disease associated with P. tenuis was a primary cause of death, and more research is needed to understand its ecology and epidemiology. Research to determine population implications of other detected pathogens at the NCWMA is warranted.

Mild COVID-19 has no detrimental effect on semen quality.

BACKGROUND: As of today, the effect of coronavirus disease 2019 (COVID-19) on male fertility remains unclear. Studies published so far have partly contradictory results, likely due to very small sample sizes and heterogeneous populations. To gain a deeper understanding of the impact of COVID-19 on male fertility, we performed a prospective case-control study, in which we examined the ejaculate of 37 subjects, including 25 subjects in the acute phase of mild COVID-19 and 12 subjects who did not suffer from COVID-19. Determination of semen parameters, severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) qPCR, and infectivity analysis were performed in the acute phase of the disease and in series. RESULTS: Semen parameter values did not differ significantly between subjects with mild COVID-19 and the control group. The serial examination of semen parameters revealed no significant changes between 4, 18, and 82 days after the onset of symptoms. SARS-CoV-2 RNA or infectious particles could not be detected in any ejaculate. CONCLUSION: Mild COVID-19 seems to have no detrimental effect on semen parameter values.

RéSUMé: CONTEXTE: À ce jour, l'effet de la maladie due au coronavirus 2019 (COVID-19) sur la fertilité masculine reste incertain. Les études publiées jusqu'à présent ont des résultats partiellement contradictoires, ce qui est probablement dû à la très petite taille des échantillons et l'hétérogénéité des populations. Pour mieux comprendre l'impact de la COVID-19 sur la fertilité masculine, nous avons réalisé une étude cas-témoins prospective, dans laquelle nous avons examiné l'éjaculat de 37 sujets, dont 25 sujets en phase aiguë de COVID-19 légère et 12 sujets qui ne souffraient pas de la COVID-19. La détermination des paramètres séminaux, la qPCR du coronavirus du syndrome respiratoire aigu sévère de type 2 (SRAS-CoV-2), et l'analyse de l'infectiosité ont été effectuées dans la phase aiguë de la maladie et dans la série. RéSULTATS: Les valeurs des paramètres du sperme ne différaient pas significativement entre les hommes atteints de la COVID-19 légère et ceux du groupe témoin. L'examen en série des paramètres du sperme n'a révélé aucun changement significatif entre 4, 18 et 82 jours après l'apparition des symptômes. L'ARN du SARS-CoV-2 ou les particules infectieuses n'ont été détectés dans aucun des éjaculats. CONCLUSION: La COVID-19 de forme légère ne semble pas avoir d'effet néfaste sur les valeurs des paramètres du sperme.

Protocol to determine the subcellular localization of protein interactions in murine keratinocytes.

Protein activities and interactions are determined by their subcellular localization. Elucidating the network of protein-protein interactions at a spatial resolution is essential for understanding the complexity of protein functions, their regulation, and cellular processes. Here, we present a protocol to determine the subcellular localization of protein interactions in non-transformed murine keratinocytes. We describe steps for nucleus/cytoplasm fractionation, immunoprecipitation from these fractions, and immunoblotting. We then detail binding quantification. For complete details on the use and execution of this protocol, please refer to Müller et al. (2023).1.

Stability and Inactivation of Monkeypox Virus on Inanimate Surfaces.

The spread of nonzoonotic monkeypox virus (MPXV) infections necessitates the reevaluation of hygiene measures. To date, only limited data are available on MPXV surface stability. Here, we evaluate the stability of infectious MPXV on stainless steel stored at different temperatures, while using different interfering substances to mimic environmental contamination. MPXV persistence increased with decreasing temperature. Additionally, we were able to show that MPXV could efficiently be inactivated by alcohol- and aldehyde-based surface disinfectants. These findings underline the stability of MPXV on inanimate surfaces and support the recommendations to use alcohol-based disinfectants as prevention measures or in outbreak situations.

Correlation of Myocardial Native T1 and Left Ventricular Reverse Remodeling after Valvular Surgery.

Myocardial native T1 is a known cardiovascular magnetic resonance (CMR) imaging biomarker to quantify diffuse myocardial fibrosis in valvular cardiomyopathy. We hypothesized that diffuse myocardial fibrosis assessed by preoperative T1 mapping might correlate with LV reverse remodeling after valvular surgery. A prospective monocentric cohort study was conducted including 79 consecutive patients with valvular cardiomyopathy referred for surgical treatment of severe aortic or severe functional mitral regurgitation. Native T1 values were assessed by CMR before surgery. LV geometry parameters (i.e., LVEDV, LVESV) were obtained by 2D transthoracic echocardiography before and six months after surgery. Postoperative change of LV geometry parameters was calculated as delta (∆) variable (i.e., six months value minus baseline value). Mean native T1 was 1047 ± 39 ms, mean ∆LVEDV was -33 ± 42 mL, and mean ∆LVESV was -15 ± 27 mL. Native T1 values correlated with ∆LVEDV (Pearson r = 0.29; p = 0.009) and ∆LVESV (Pearson r = 0.29; p = 0.015). Native T1 values < 1073 ms were identified as independent predictor of postoperative reduction of LVEDV (HR 3.0; 95%-CI: 1.1-8.0; p = 0.03) and LVESV (HR 2.9; 95%-CI: 1.1-7.4; p = 0.03). Diffuse myocardial fibrosis assessed by myocardial native T1 correlates with LV reverse remodeling at six months after valvular surgery. T1 mapping may be a valuable tool to predict LV reverse remodeling in valvular heart disease.

Moderate dietary salt restriction improves blood pressure and mental well-being in patients with primary aldosteronism: The salt CONNtrol trial.

BACKGROUND: Primary aldosteronism (PA) is a frequent cause of hypertension. Aldosterone excess together with high dietary salt intake aggravates cardiovascular damage, despite guideline-recommended mineralocorticoid receptor antagonist (MRA) treatment. OBJECTIVES: To investigate the antihypertensive impact of a moderate dietary salt restriction and associated physiological changes, including mental well-being. METHODS: A total of 41 patients with PA on a stable antihypertensive regimen-including MRA-followed a dietary salt restriction for 12 weeks with structured nutritional training and consolidation by a mobile health app. Salt intake and adherence were monitored every 4 weeks using 24-h urinary sodium excretion and nutrition protocols. Body composition was assessed by bioimpedance analysis and mental well-being by validated questionnaires. RESULTS: Dietary salt intake significantly decreased from 9.1 to 5.2 g/d at the end of the study. In parallel, systolic (130 vs. 121 mm Hg) and diastolic blood pressure (BP) (84 vs. 81 mm Hg) improved significantly. Patients' aptitude of estimating dietary salt content was refined significantly (underestimation by 2.4 vs. 1.4 g/d). Salt restriction entailed a significant weight loss of 1.4 kg, improvement in pulse pressure (46 vs. 40 mm Hg) and normalization of depressive symptoms (PHQD scale, p < 0.05). Salt restriction, cortisol after dexamethasone suppression test and dosage of renin-angiotensin-aldosterone-system (RAAS) blockers were independently associated with BP reduction. CONCLUSION: A moderate restriction of dietary salt intake in patients with PA substantially reduces BP and depressive symptoms. Moreover, the findings underline that a sufficient RAAS blockade seems to augment the effects of salt restriction on BP and cardiovascular risk.

Glucocorticoid receptor polymorphism BclI with increased glucocorticoid sensitivity has a positive influence on quality of life in endogenous Cushing's syndrome in remission.

CONTEXT: Patients with endogenous Cushing's syndrome (CS) may suffer from a wide range of neuropsychiatric symptoms leading to impaired quality of life (QoL). OBJECTIVE: Glucocorticoid receptor (GR) polymorphisms are associated with increased (BclI and N363S) or decreased (A3669G and ER22/23EK) GR sensitivity. HYPOTHESIS: GR genotypes may modulate and affect QoL and recovery after remission differently via GR sensitivity. METHODS: 295 patients with endogenous CS (81 active, 214 in remission) from 3 centers of the German Cushing's Registry were included for the cross-sectional analysis. All subjects were assessed with three questionnaires (CushingQoL, Tuebingen CD-25, SF-36). For the longitudinal part, 120 patients of them were analyzed at baseline and after 1.5 ± 0.9 yrs of follow-up. DNA samples were obtained from peripheral blood leukocytes for GR genotyping. RESULTS: Patients in remission scored significantly better than patients with active CS in the CushingQoL questionnaire and in the SF-36 sub-categories physical and social functioning, role-physical, bodily pain, and vitality. In cross-sectional analysis, no differences in QoL between minor allele and wildtype carriers were detected for all polymorphisms in active or cured CS. In longitudinal analysis, however, carriers with BclI minor allele showed significant improvement in SF-36 sub-categories vitality (P = .038) and mental health (P = .013) compared to wildtype carriers (active CS at baseline vs. CS in remission at follow-up). The outcome of the two questionnaires CushingQoL and Tuebingen CD-25 improved significantly in both wildtype and minor allele carriers. CONCLUSION: BclI minor allele carriers initially had the lowest QoL but recovered better from impaired QoL than wildtype carriers.

Proteomic Analysis in Valvular Cardiomyopathy: Aortic Regurgitation vs. Aortic Stenosis.

Left ventricular (LV) reverse remodeling after aortic valve (AV) surgery is less predictable in chronic aortic regurgitation (AR) than in aortic stenosis (AS). We aimed to disclose specific LV myocardial protein signatures possibly contributing to differential disease progression. Global protein profiling of LV myocardial samples excised from the subaortic interventricular septum in patients with isolated AR or AS undergoing AV surgery was performed using liquid chromatography-electrospray ionization-tandem mass spectrometry. Based on label-free quantitation protein intensities, a logistic regression model was calculated and adjusted for age, sex and protein concentration. Web-based functional enrichment analyses of phenotype-associated proteins were performed utilizing g:Profiler and STRING. Data are available via ProteomeXchange with identifier PXD039662. Lysates from 38 patients, including 25 AR and 13 AS samples, were analyzed. AR patients presented with significantly larger LV diameters and volumes (end-diastolic diameter: 61 (12) vs. 48 (13) mm, p < 0.001; end-diastolic volume: 180.0 (74.6) vs. 92.3 (78.4), p = 0.001). A total of 171 proteins were associated with patient phenotype: 117 were positively associated with AR and the enrichment of intracellular compartment proteins (i.e., assigned to carbohydrate and nucleotide metabolism, protein biosynthesis and the proteasome) was detected. Additionally, 54 were positively associated with AS and the enrichment of extracellular compartment proteins (i.e., assigned to the immune and hematopoietic system) was observed. In summary, functional enrichment analysis revealed specific AR- and AS-associated signatures of LV myocardial proteins.

Efficient virus detection utilizing chitin-immobilized nanobodies synthesized in Ustilago maydis.

The COVID-19 pandemic has greatly impacted the global economy and health care systems, illustrating the urgent need for timely and inexpensive responses to pandemic threats in the form of vaccines and antigen tests. Currently, antigen testing is mostly conducted by qualitative flow chromatography or via quantitative ELISA-type assays. The latter mostly utilize materials like protein-adhesive polymers and gold or latex particles. Here we present an alternative ELISA approach using inexpensive, biogenic materials and permitting quick detection based on components produced in the microbial model Ustilago maydis. In this fungus, heterologous proteins like biopharmaceuticals can be exported by fusion to unconventionally secreted chitinase Cts1. As a unique feature, the carrier chitinase binds to chitin allowing its additional use as a purification or immobilization tag. Recent work has demonstrated that nanobodies are suitable target proteins. These proteins represent a very versatile alternative antibody format and can quickly be adapted to detect novel antigens by camelidae immunization or synthetic libraries. In this study, we exemplarily produced different mono- and bivalent SARS-CoV-2 nanobodies directed against the spike protein receptor binding domain (RBD) as Cts1 fusions and screened their antigen binding affinity in vitro and in vivo. Functional nanobody-Cts1 fusions were immobilized on chitin forming an RBD tethering surface. This provides a solid base for future development of inexpensive antigen tests utilizing unconventionally secreted nanobodies as antigen trap and a matching ubiquitous and biogenic surface for immobilization.