Gut Microbiota Perturbation in IgA Deficiency Is Influenced by IgA-Autoantibody Status.

BACKGROUND & AIMS: IgA exerts its primary function at mucosal surfaces, where it binds microbial antigens to regulate bacterial growth and epithelial attachment. One third of individuals with IgA deficiency (IgAD) suffers from recurrent mucosal infections, possibly related to an altered microbiota. We aimed to delineate the impact of IgAD and the IgA-autoantibody status on the composition and functional capacity of the gut microbiota. METHODS: We performed a paired, lifestyle-balanced analysis of the effect of IgA on the gut microbiota composition and functionality based on fecal samples from individuals with IgAD and IgA-sufficient household members (n = 100), involving quantitative shotgun metagenomics, species-centric functional annotation of gut bacteria, and strain-level analyses. We supplemented the data set with 32 individuals with IgAD and examined the influence of IgA-autoantibody status on the composition and functionality of the gut microbiota. RESULTS: The gut microbiota of individuals with IgAD exhibited decreased richness and diversity and was enriched for bacterial species encoding pathogen-related functions including multidrug and antimicrobial peptide resistance, virulence factors, and type III and VI secretion systems. These functional changes were largely attributed to Escherichia coli but were independent of E coli strain variations and most prominent in individuals with IgAD with IgA-specific autoreactive antibodies. CONCLUSIONS: The microbiota of individuals with IgAD is enriched for species holding increased proinflammatory potential, thereby potentially decreasing the resistance to gut barrier-perturbing events. This phenotype is especially pronounced in individuals with IgAD with IgA-specific autoreactive antibodies, thus warranting a screening for IgA-specific autoreactive antibodies in IgAD to identify patients with IgAD with increased risk for gastrointestinal implications.

Sensitive and specific serological ELISA for the detection of SARS-CoV-2 infections.

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has triggered the worldwide coronavirus disease 2019 (COVID-19) pandemic. Serological assays for the detection of SARS-CoV-2 infections are important to understand the immune response in patients and to obtain epidemiological data about the number of infected people, especially to identify asymptomatic persons not aware of a past infection. METHODS: We recombinantly produced SARS-CoV-2 nucleocapsid (N)-protein in Escherichia coli. We used the purified protein to develop an indirect enzyme-linked immunosorbent assay (ELISA) for the detection of SARS-CoV-2 specific antibodies. This ELISA method was optimized and validated with serum samples collected from 113 patients with RT-PCR-confirmed SARS-CoV-2 infections including hospitalized COVID-19 patients and 1500 control sera mostly collected before 2015 with different clinical background. RESULTS: The optimized N-protein-ELISA provided a sensitivity of 89.7% (n = 68) for samples collected from patients with confirmed SARS-CoV-2 infections and mild to severe symptoms more than 14 days after symptom onset or a positive PCR test. The antibody levels remained low for serum samples collected in the first six days (n = 23) and increased in the second week (n = 22) post symptom onset or PCR confirmation. At this early phase, the ELISA provided a sensitivity of 39.1% and 86.4%, respectively, reflecting the time of an IgG immune response against pathogens. The assay specificity was 99.3% (n = 1500; 95% CI 0.995-0.999). Serum samples from persons with confirmed antibody titers against human immunodeficiency viruses 1/2, parvovirus B19, hepatitis A/B virus, cytomegalovirus, Epstein Barr virus, and herpes simplex virus were tested negative. CONCLUSIONS: We conclude that the N-protein-based ELISA developed here is well suited for the sensitive and specific serological detection of SARS-CoV-2 specific IgG antibodies in human serum for symptomatic infections. It may also prove useful to identify previous SARS-CoV-2 infections in vaccinated people, as all currently approved vaccines rely on the SARS-CoV-2 spike (S-) protein.

CD99 and polymeric immunoglobulin receptor peptides deregulation in critical COVID-19: A potential link to molecular pathophysiology?

Identification of significant changes in urinary peptides may enable improved understanding of molecular disease mechanisms. We aimed towards identifying urinary peptides associated with critical course of COVID-19 to yield hypotheses on molecular pathophysiological mechanisms in disease development. In this multicentre prospective study urine samples of PCR-confirmed COVID-19 patients were collected in different centres across Europe. The urinary peptidome of 53 patients at WHO stages 6-8 and 66 at WHO stages 1-3 COVID-19 disease was analysed using capillary electrophoresis coupled to mass spectrometry. 593 peptides were identified significantly affected by disease severity. These peptides were compared with changes associated with kidney disease or heart failure. Similarities with kidney disease were observed, indicating comparable molecular mechanisms. In contrast, convincing similarity to heart failure could not be detected. The data for the first time showed deregulation of CD99 and polymeric immunoglobulin receptor peptides and of known peptides associated with kidney disease, including collagen and alpha-1-antitrypsin. Peptidomic findings were in line with the pathophysiology of COVID-19. The clinical corollary is that COVID-19 induces specific inflammation of numerous tissues including endothelial lining. Restoring these changes, especially in CD99, PIGR and alpha-1-antitripsin, may represent a valid and effective therapeutic approach in COVID-19, targeting improvement of endothelial integrity.

Deciphering the Transcriptomic Heterogeneity of Duodenal Coeliac Disease Biopsies.

Coeliac disease (CD) is a clinically heterogeneous autoimmune disease with variable presentation and progression triggered by gluten intake. Molecular or genetic factors contribute to disease heterogeneity, but the reasons for different outcomes are poorly understood. Transcriptome studies of tissue biopsies from CD patients are scarce. Here, we present a high-resolution analysis of the transcriptomes extracted from duodenal biopsies of 24 children and adolescents with active CD and 21 individuals without CD but with intestinal afflictions as controls. The transcriptomes of CD patients divide into three groups-a mixed group presenting the control cases, and CD-low and CD-high groups referring to lower and higher levels of CD severity. Persistence of symptoms was weakly associated with subgroup, but the highest marsh stages were present in subgroup CD-high, together with the highest cell cycle rates as an indicator of virtually complete villous atrophy. Considerable variation in inflammation-level between subgroups was further deciphered into immune cell types using cell type de-convolution. Self-organizing maps portrayal was applied to provide high-resolution landscapes of the CD-transcriptome. We find asymmetric patterns of miRNA and long non-coding RNA and discuss the effect of epigenetic regulation. Expression of genes involved in interferon gamma signaling represent suitable markers to distinguish CD from non-CD cases. Multiple pathways overlay in CD biopsies in different ways, giving rise to heterogeneous transcriptional patterns, which potentially provide information about etiology and the course of the disease.

Lower HbA1c in patients with type 1 diabetes and celiac disease who reached celiac-specific antibody-negativity-A multicenter DPV analysis.

OBJECTIVES: To study celiac-specific antibody status over 3 years in patients with type 1 diabetes and biopsy-proven celiac disease (T1D + CD). Furthermore, to determine clinical differences after diagnosis between patients reaching constant antibody-negativity (Ab-neg) and staying antibody-positive (Ab-pos). METHODS: A total of 608 pediatric T1D + CD patients from the multicenter DPV registry were studied longitudinally regarding their CD specific antibody-status. Differences between Ab-neg (n = 218) and Ab-pos (n = 158) patients 3 years after biopsy were assessed and compared with 26 833 T1D patients without CD by linear and logistic regression adjusted for age, gender, diabetes duration and migration background. RESULTS: Thirty-six percent of T1D + CD patients reached and sustained antibody-negativity 3 years after CD diagnosis. The median time until patients returned to Ab-neg was 0.86 (0.51;1.16) years. Three years after diagnosis, HbA1c was lowest in Ab-neg and highest in Ab-pos patients compared to T1D-only patients (adjusted mean (95%CI): 7.72 (7.51-7.92) % vs 8.44 (8.20-8.68) % vs 8.19 (8.17-8.21) %, adjusted P < 0.001, respectively). Total cholesterol, LDL-cholesterol and frequency of dyslipidemia were significantly lower in Ab-neg compared to T1D-only patients (167 (161-173) mg/dl vs 179 (178-179) mg/dl, P < .001; 90 (84-96) mg/dl vs 99 (98-99) mg/dl, P = .005; 15.7 (10.5-22.9) % vs 25.9 (25.2-26.6) %, P = .017). In longitudinal analyses over 6 years after diagnosis, a constantly higher HbA1c (P < .001) and a lower height-SDS (P = .044) was observed in Ab-pos compared to Ab-neg patients. CONCLUSION: Only one third of T1D + CD patients reached constant Ab-negativity after CD diagnosis. Achieving Ab-negativity after diagnosis seems to be associated with better metabolic control and growth, supposedly due to a higher adherence to therapy in general.

The association between socio-economic status and diabetes care and outcome in children with diabetes type 1 in Germany: The DIAS study (diabetes and social disparities).

OBJECTIVE: To evaluate the association between socioeconomic status (SES) and diabetes outcomes in German children and adolescents. METHODS: A total of 1829 subjects <18 years old with type 1 diabetes mellitus from 13 German diabetes centers were included from June 2013 until June 2014. Data were collected within the multicenter DPV (Diabetes Prospective Follow-up) registry. SES was measured with a composite index. Multivariable regression models were applied to analyze the association of SES and outcomes adjusted for age, sex, diabetes duration, and migration status. RESULTS: Low SES was significantly associated with worse diabetes outcomes: higher hemoglobin A1C (HbA1c) (64.3 mmol/mol), lower proportion of insulin pump therapy (43.6%), fewer daily self-monitored blood glucose (SMBG) measurements (5.7), more inpatient days per patient-year (5.8) compared to patients with medium/high SES (HbA1c: 61.3 mmol/mol, P < 0.001/59.8 mmol/mol, P < 0.0001; proportion of pump therapy: 54.5%, P < 0.01/ 54.9%, P < 0.01; SMBG: 6.0, P < 0.01/ 6.1, P < 0.01; inpatient days: 4.5, P < 0.0001/3.4, P < 0.0001). The inclusion of migration status in the models resulted in only minor changes in the outcomes. CONCLUSION: Despite free health care, low SES is associated with unfavorable diabetes outcomes in Germany. The poorer diabetes outcomes of children with diabetes have been attributed to their migration status and may be partly explained by low SES. Both factors must become part of targeted diabetes care in children and adolescents with type 1 diabetes.

Antibody Concentrations Decrease 14-Fold in Children With Celiac Disease on a Gluten-Free Diet but Remain High at 3 Months.

BACKGROUND & AIMS: Celiac disease can be identified by a serologic test for IgA against tissue transglutaminase (IgA-TTG) in a large proportion of children. However, the increased concentrations of antibody rarely normalize within the months after children are placed on a gluten-free diet (GFD). Early serologic predictors of sufficient adherence to GFD are required for optimal treatment. METHODS: In a prospective study, we observed the response to a GFD in 345 pediatric patients (67% girls; mean age, 8.4 y) who underwent duodenal biopsy to confirm or refute celiac disease from October 2012 through December 2015. Baseline serum samples were tested centrally for IgA-TTG and IgG against deamidated gliadin. Follow-up serologic analyses of children on a GFD were performed about 3 months later. RESULTS: The geometric mean concentration of IgA-TTG decreased from 72.4-fold to 5.2-fold the upper limit of normal (ULN), or by a factor of 14.0 (95% CI, 12.0-16.4). A substantial response (defined as a larger change than the typical variation in patients not on a GFD) was observed in 80.6% of the children. Only 28.1% of patients had a substantial response in the concentration of IgG against deamidated gliadin. Concentration of IgA-TTG remained above 1-fold the ULN in 83.8% of patients, and above 10-fold the ULN in 26.6% of patients with a substantial response. CONCLUSIONS: Serum concentration of IgA-TTG decreases substantially in most children with celiac disease within 3 months after they are placed on a GFD, but does not normalize in most. This information on changes in antibody concentrations can be used to assess patient response to the diet at short-term follow-up evaluations. Patients with a substantial response to a GFD often still have high antibody levels after 3 months. German Clinical Trials Registry no. DRKS00003854.

Validation of Antibody-Based Strategies for Diagnosis of Pediatric Celiac Disease Without Biopsy.

BACKGROUND & AIMS: A diagnosis of celiac disease is made based on clinical, genetic, serologic, and duodenal morphology features. Recent pediatric guidelines, based largely on retrospective data, propose omitting biopsy analysis for patients with concentrations of IgA against tissue transglutaminase (IgA-TTG) >10-fold the upper limit of normal (ULN) and if further criteria are met. A retrospective study concluded that measurements of IgA-TTG and total IgA, or IgA-TTG and IgG against deamidated gliadin (IgG-DGL) could identify patients with and without celiac disease. Patients were assigned to categories of no celiac disease, celiac disease, or biopsy required, based entirely on antibody assays. We aimed to validate the positive and negative predictive values (PPV and NPV) of these diagnostic procedures. METHODS: We performed a prospective study of 898 children undergoing duodenal biopsy analysis to confirm or rule out celiac disease at 13 centers in Europe. We compared findings from serologic analysis with findings from biopsy analyses, follow-up data, and diagnoses made by the pediatric gastroenterologists (celiac disease, no celiac disease, or no final diagnosis). Assays to measure IgA-TTG, IgG-DGL, and endomysium antibodies were performed by blinded researchers, and tissue sections were analyzed by local and blinded reference pathologists. We validated 2 procedures for diagnosis: total-IgA and IgA-TTG (the TTG-IgA procedure), as well as IgG-DGL with IgA-TTG (TTG-DGL procedure). Patients were assigned to categories of no celiac disease if all assays found antibody concentrations <1-fold the ULN, or celiac disease if at least 1 assay measured antibody concentrations >10-fold the ULN. All other cases were considered to require biopsy analysis. ULN values were calculated using the cutoff levels suggested by the test kit manufacturers. HLA typing was performed for 449 participants. We used models that considered how specificity values change with prevalence to extrapolate the PPV and NPV to populations with lower prevalence of celiac disease. RESULTS: Of the participants, 592 were found to have celiac disease, 345 were found not to have celiac disease, and 24 had no final diagnosis. The TTG-IgA procedure identified patients with celiac disease with a PPV of 0.988 and an NPV of 0.934; the TTG-DGL procedure identified patients with celiac disease with a PPV of 0.988 and an NPV of 0.958. Based on our extrapolation model, we estimated that the PPV and NPV would remain >0.95 even at a disease prevalence as low as 4%. Tests for endomysium antibodies and HLA type did not increase the PPV of samples with levels of IgA-TTG ≥10-fold the ULN. Notably, 4.2% of pathologists disagreed in their analyses of duodenal morphology-a rate comparable to the error rate for serologic assays. CONCLUSIONS: In a prospective study, we validated the TTG-IgA procedure and the TTG-DGL procedure in identification of pediatric patients with or without celiac disease, without biopsy. German Clinical Trials Registry no.: DRKS00003854.

Will the Real Coeliac Disease Please Stand Up? Coeliac Disease Prevalence in the German LIFE Child Study.

OBJECTIVES: Assessing the seroprevalence and the prevalence of definite coeliac disease (CD) in the German LIFE Child Health study cohort including immunoglobulin A (IgA) antibodies against tissue transglutaminase (IgA-TTG) in addition to IgG antibodies against deamidated gliadin peptides (IgG-DGP) and human leukocyte antigen (HLA)-DQ2/8 genotyping. METHODS: Samples from children and adolescents were first screened for IgA-TTG and IgG-DGP. If IgA-TTG was above 0.5 times the upper limit of normal and/or IgG-DGP was positive, IgA antibodies against endomysium (IgA-EmA) were measured, and HLA was genotyped. In patients with only IgG-DGP positivity, total IgA was assayed. Subjects with suspicious results were followed up serologically and, in case of repeatedly positive antibody results, invited for a personal interview. Further diagnostic data were obtained independent from our study. RESULTS: We screened 2363 children's blood samples collected from 2011 to 2015. The seroprevalence, that is, IgA-TTG and/or IgA-EmA positivity or IgG-DGP positivity with IgA <0.05 g/L, was 1.57% (95% confidence interval [CI95%] 1.14-2.15). The prevalence of suspected CD, that is, seroprevalence and compatible HLA genotype with hitherto unknown mucosal damage, was 1.35% (CI95% 0.96-1.91). Definite CD, that is, seropositivity accompanied by positive intestinal biopsy or IgA-TTG ≥ 10 × upper limit of normal, was found in 0.42% (CI95% 0.22-0.80). Seven children claimed to have CD. The HLA haplotype, however, matched in only 4 of them resulting in an overall CD prevalence of at least 0.59% (CI95% 0.34-1.02). Thirteen unclear cases remained; therefore, the prevalence may even be higher. CONCLUSIONS: The prevalence of definite CD in a population-representative German cohort is higher than previously described. HLA-DQ typing is helpful to identify false-positive IgA-TTG patients negative for IgA-EmA and/or IgG-DGP under screening conditions and unmasks possible misdiagnoses of CD.

Hemolysis and IgA-antibodies against tissue transglutaminase: When are antibody test results no longer reliable?

BACKGROUND: Antibodies against tissue transglutaminase (TTG) of isotype IgA (IgA-aTTG) represent reliable diagnostic markers to confirm or exclude celiac disease (CD). Hemolysis (HL) is an important pre-analytical factor. HL can be quantified as HL index (HI) correlating with the concentration of free hemoglobin. TTG is abundant in erythrocytes and released upon HL. In immunoassays, the released TTG may interfere with binding of IgA-aTTG to the coated TTG. METHODS: We selected 17 HL-free sera from children with biopsy-confirmed CD: 7 with low-positive (1-5 multiples of upper limit of normal [×ULN]), 5 with intermediate (5-10 × ULN) and 5 with high IgA-aTTG (10-15 × ULN). Sera were spiked with hemolysates resulting in HIs ranging from 12.5 to 800 (12.5-800 mg/dL free hemoglobin). RESULTS: IgA-aTTG values were significantly decreased (>10%) after addition of hemolysates even if HL was invisible (HI <50). This effect is diagnosis-relevant if IgA-aTTG values are measured just below the cut-offs: (i) 0.4-1 × ULN at HI ≥25 (CD not excludable) and (ii) 8.5-10 × ULN at HI ≥200 (diagnosis of CD without biopsy not possible). Antibodies against deamidated gliadin were not influenced by HL. CONCLUSIONS: IgA-aTTG results in sera with HI ≥25 can yield inconclusive results. Therefore, those antibody results should be assessed only under consideration of the HI.

Vascular risk factors in children, adolescents, and young adults with type 1 diabetes complicated by celiac disease: results from the DPV initiative.

OBJECTIVE: Celiac disease (CD) is a common comorbidity of type 1 diabetes (T1D). Long-term consequences of CD are not completely understood, and adhering to a gluten-free diet is a burden for many patients. We investigated the effect of CD on vascular risk factors in a large cohort of T1D patients aged <20 yr. RESEARCH DESIGN AND METHODS: Within the longitudinal Diabetes Patienten Verlaufsdokumentation (DPV)-diabetes registry, data were analyzed from 59,909 < 20-yr-old T1D patients treated at 392 centers in Germany and Austria. A total of 974 patients with biopsy-proven celiac disease (BPCD) were compared with 28,398 patients without CD with respect to blood pressure (BP), lipids, glycohemoglobin (HbA1c ), body mass index (BMI), and reported smoking behavior. RESULTS: Patients with T1D and BPCD showed significantly lower high-density lipoprotein (HDL) cholesterol levels [median (interquartile range): 53.0 (43.0-62.6) mg/dL] than patients without CD [55.0 (45.0-66.0) mg/dL; p < 0.01; p < 0.001 after adjustment for confounding variables]. Systolic BP was lower in patients with CD [105.5 (100.0-112.5) mmHg] than in patients without CD [110.0 (102.0-117.0) mmHg; p < 0.0001; p < 0.001 after adjustment]. There were no significant differences regarding smoking behavior, BMI, or HbA1c . In a subgroup of 335 patients with BPCD, HDL cholesterol was measured 1 yr after diagnosis of CD:HDL increased by 8% (p < 0.01). CONCLUSION: Young people with T1D and CD have lower HDL cholesterol values than patients without CD. As low HDL cholesterol is associated with vascular risk, our findings support screening for CD and monitoring of HDL cholesterol in young people with T1D.

Non-binary phase gratings for x-ray imaging with a compact Talbot interferometer.

X-ray imaging using a Talbot-Lau interferometer, consisting of three binary gratings, is a well-established approach to acquire x-ray phase-contrast and dark-field images with a polychromatic source. However, challenges in the production of high aspect ratio gratings limit the construction of a compact setup for high x-ray energies. In this study we consider the use of phase gratings with triangular-shaped structures in an x-ray interferometer and show that such gratings can yield high visibilities for significantly shorter propagation distances than conventional gratings with binary structures. The findings are supported by simulation and experimental results for both cases of a monochromatic and a polychromatic source.

The influence of IL-10 and TNFα on chondrogenesis of human mesenchymal stromal cells in three-dimensional cultures.

Chondrogenic differentiated mesenchymal stromal cells (MSCs) are a promising cell source for articular cartilage repair. This study was undertaken to determine the effectiveness of two three-dimensional (3D) culture systems for chondrogenic MSC differentiation in comparison to primary chondrocytes and to assess the effect of Interleukin (IL)-10 and Tumor Necrosis Factor (TNF)α on chondrogenesis by MSCs in 3D high-density (H-D) culture. MSCs were isolated from femur spongiosa, characterized using a set of typical markers and introduced in scaffold-free H-D cultures or non-woven polyglycolic acid (PGA) scaffolds for chondrogenic differentiation. H-D cultures were stimulated with recombinant IL-10, TNFα, TNFα + IL-10 or remained untreated. Gene and protein expression of type II collagen, aggrecan, sox9 and TNFα were examined. MSCs expressed typical cell surface markers and revealed multipotency. Chondrogenic differentiated cells expressed cartilage-specific markers in both culture systems but to a lower extent when compared with articular chondrocytes. Chondrogenesis was more pronounced in PGA compared with H-D culture. IL-10 and/or TNFα did not impair the chondrogenic differentiation of MSCs. Moreover, in most of the investigated samples, despite not reaching significance level, IL-10 had a stimulatory effect on the type II collagen, aggrecan and TNFα expression when compared with the respective controls.

Comparative Analysis of Lymphocyte Populations in Post-COVID-19 Condition and COVID-19 Convalescent Individuals.

Reduced lymphocyte counts in peripheral blood are one of the most common observations in acute phases of viral infections. Although many studies have already examined the impact of immune (dys)regulation during SARS-CoV-2 infection, there are still uncertainties about the long-term consequences for lymphocyte homeostasis. Furthermore, as persistent cellular aberrations have been described following other viral infections, patients with "Post-COVID-19 Condition" (PCC) may present similarly. In order to investigate cellular changes in the adaptive immune system, we performed a retrospective analysis of flow cytometric data from lymphocyte subpopulations in 106 patients with confirmed SARS-CoV-2 infection who received medical care at our institution. The patients were divided into three groups according to the follow-up date; laboratory analyses of COVID-19 patients were compared with 28 unexposed healthy controls. Regarding B lymphocyte subsets, levels of IgA + CD27+, IgG + CD27+, IgM + CD27- and switched B cells were significantly reduced at the last follow-up compared to unexposed healthy controls (UHC). Of the 106 COVID-19 patients, 56 were clinically classified as featuring PCC. Significant differences between PCC and COVID-19 convalescents compared to UHC were observed in T helper cells and class-switched B cells. However, we did not detect specific or long-lasting immune cellular changes in PCC compared to the non-post-COVID-19 condition.

Influence of Mutations and N-Glycosylation Sites in the Receptor-Binding Domain (RBD) and the Membrane Protein of SARS-CoV-2 Variants of Concern on Antibody Binding in ELISA.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can infect human cells by first attaching to the ACE-2 receptor via its receptor-binding domain (RBD) in the spike protein. Here, we report the influence of N-glycosylation sites of the RBD and the membrane (M) protein on IgG antibody binding in serum samples from patients infected with the original SARS-CoV-2 strain in Germany. The RBDs of the wildtype, alpha, beta, gamma, and kappa variants expressed in HEK293S GnTI- cells were all N-glycosylated at Asn331, Asn334, Asn343, and Asn360 or Asn370, whereas the M-protein was glycosylated at Asn5. An ELISA using a coated RBD and probed with anti-RBD IgG antibodies gave a sensitivity of 96.3% and a specificity of 100% for the wildtype RBD, while the sensitivity decreased by 5% to 10% for the variants of concern, essentially in the order of appearance. Deglycosylation of the wildtype RBD strongly reduced antibody recognition by ~20%, considering the mean of the absorbances recorded for the ELISA. This effect was even stronger for the unglycosylated RBD expressed in Escherichia coli, suggesting structural changes affecting epitope recognition. Interestingly, the N-glycosylated M-protein expressed in HEK293S GnTI- cells gave good sensitivity (95%), which also decreased to 65% after deglycosylation, and selectivity (100%). In conclusion, N-glycosylation of the M-protein, the RBD, and most likely the spike protein are important for proper antibody binding and immunological assays, whereas the type of N-glycosylation is less relevant.

Perceived illness consequences predict the long-term course of handicap in patients with vertigo and dizziness beyond vestibular abnormality.

OBJECTIVE: Vertigo and dizziness (VD) affect one third of the population during their lifetime. VD patients are oftentimes severely handicapped. One current study showed that illness perceptions, emotional as well as behavioral responses to illness were associated with VD-related handicap at 3-months follow-up. However, no study has yet investigated this association for a period longer than six months. This study aimed to investigate long-term associations of cognitive, emotional, and behavioral factors with VD-related handicap. METHODS: In a naturalistic longitudinal study design, n = 161 patients with VD were examined at baseline, at 6-months follow-up, and at 12-months follow-up. Participants underwent neurological and psychiatric examinations as well as comprehensive psychological assessments using self-report questionnaires. RESULTS: During the study period VD-related handicap decreased significantly (Cohen's d = .35, p < .001). Cognitive, emotional, and behavioral factors remained without significant change during the study period. Vestibular testing as well as the type of diagnosis were not associated with changes in VD-related handicap. Changes in perceived illness consequences (ß = .265, p < .001), depression (ß = .257, p < .001), and anxiety (ß = .206, p = .008) significantly predicted the course of VD-related handicap over 12 months, while the presence vs. absence of vestibular abnormality did not. CONCLUSION: Our results extend findings that cognitive and emotional factors including perceived illness consequences, depression, and anxiety are associated with the long-term course of VD-related handicap and may provide therapeutic targets to improve long-term outcomes in patients with VD.

Detection of Antibodies against Endemic and SARS-CoV-2 Coronaviruses with Short Peptide Epitopes.

(1) Background: Coronavirus proteins are quite conserved amongst endemic strains (eCoV) and SARS-CoV-2. We aimed to evaluate whether peptide epitopes might serve as useful diagnostic biomarkers to stratify previous infections and COVID-19. (2) Methods: Peptide epitopes were identified at an amino acid resolution that applied a novel statistical approach to generate data sets of potential antibody binding peptides. (3) Results: Data sets from more than 120 COVID-19 or eCoV-infected patients, as well as vaccinated persons, have been used to generate data sets that have been used to search in silico for potential epitopes in proteins of SARS-CoV-2 and eCoV. Peptide epitopes were validated with >300 serum samples in synthetic peptide micro arrays and epitopes specific for different viruses, in addition to the identified cross reactive epitopes. (4) Conclusions: Most patients develop antibodies against non-structural proteins, which are useful general markers for recent infections. However, there are differences in the epitope patterns of COVID-19, and eCoV, and the S-protein vaccine, which can only be explained by a high degree of cross-reactivity between the viruses, a pre-existing immune response against some epitopes, and even an alternate processing of the vaccine proteins.

Suicidal behaviors and adverse childhood experiences: A cross-diagnostic study in persistent depressive disorder and borderline personality disorder.

Adverse childhood experiences (ACE) constitute a known risk factor for suicidality. There is a research gap regarding differential patterns of associations between variants of suicidal ideations and behaviors (SIB) and characteristics of ACE in severe mental disorders. This cross-diagnostic study investigates whether SIB are related to ACE subtypes in two high-risk conditions, i.e., persistent depressive disorder (PDD) and borderline personality disorder (BPD). Inpatients with PDD (n = 117; age 40.2 years ± 12.3) and BPD (n = 74; age 26.2 ± 7.9) were assessed with the Columbia-Suicide Severity Rating Scale for suicidal ideations (SI), suicidal behaviors (SB) and actual suicide attempts (SA); ACE were recorded with the Childhood Trauma Questionnaire. In PDD, SI and SA were associated with childhood physical abuse (ORs 7.2 and 2.3, respectively). In BPD, SA were associated with severe experiences of physical abuse (OR 6.5). Weaker yet significant associations were found for childhood emotional abuse in PDD with SB (including SA), and in BPD with SA. Recall of childhood physical abuse may be clinically relevant information for identifying particular risks of SIB. Future studies should investigate these differential patterns in more depth and in terms of causality.

Growth in children and adolescents with type 1 diabetes.

OBJECTIVE: To investigate the effect of type 1 diabetes on growth and adult height. STUDY DESIGN: Data from 22 651 children (10 494 females) with type 1 diabetes documented at onset of the disease from specialized centers in Germany and Austria were analyzed. Patients of non-German and non-Austrian origin and patients with celiac disease were excluded from the analysis. Near-adult height data were available in 1685 patients. RESULTS: At the time of diagnosis of type 1 diabetes, the mean age of the 22 651 children was 8.8 ± 4.2 years, with a mean height SDS of 0.22 ± 1.0. The 1685 patients with diabetes onset before age 11 years reached a mean adult height of -0.16 ± 1.0 SDS. Mean adult height was was 167.1 ± 6.2 cm (-0.16 ± 0.97 SDS) in females (n = 846) and 179.6 ± 7.1 cm (-0.17 ± 1.0 SDS) in males (n = 839). Mean duration of diabetes was 9.1 ± 2.6 years, and mean Hemoglobin A1c concentration was 7.9% ± 1.2% (63 ± 10 mmol/mol). In a multivariate regression model, adult height was positively correlated with height at onset of diabetes (P < .0001) and negatively with mean Hemoglobin A1c (P < .0001) and duration of diabetes (P = .0015). CONCLUSION: Height at the time of diagnosis of type 1 diabetes is above average. Even with intensive insulin therapy, growth and adult height remain indicators of metabolic diabetes control in the 21st century.

Evaluation of Simple Lateral Flow Immunoassays for Detection of SARS-CoV-2 Neutralizing Antibodies.

Immunization for the generation of protective antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged to be highly effective in preventing hospital admission, need for intensive care treatment and high mortality in the current SARS-CoV-2 pandemic. Lateral flow immune assays (LFIAs) offer a simple and competitive option to monitor antibody production after vaccination. Here, we compared the diagnostic performance of three different lateral flow assays in detecting nucleocapsid protein (NP), S1 subunit (S1) and receptor binding domain (pseudo)-neutralizing antibodies (nRBD) in sera of 107 health care workers prior (V1), two weeks (V2) after first vaccination with BNT162b2 as well as three weeks (V3) and eight months later (V4). In sera at V1, overall specificity was >99%. At V3, LFIAs showed sensitivities between 98.1 and 100%. The comparison of S1 and nRBD LFIA with S1 ELISA and a focus reduction neutralization assay (FRNT) revealed high concordance at V3. Thus, the use of lateral flow immunoassays appears to have reasonable application in the short-term follow-up after vaccination for SARS-CoV-2.