Negative Selection on a SOD1 Mutation Limits Canine Degenerative Myelopathy While Avoiding Inbreeding

Several hundred disease-causing mutations are currently known in domestic dogs. Breeding management is therefore required to minimize their spread. Recently, genetic methods such as direct-to-consumer testing have gained popularity; however, their effects on dog populations are unclear. Here, we aimed to evaluate the influence of genetic testing on the frequency of mutations responsible for canine degenerative myelopathy and assess the changes in the genetic structure of a Pembroke Welsh corgi population from Japan. Genetic testing of 5,512 dogs for the causative mutation in superoxide dismutase 1 (SOD1) (c.118G>A (p.E40K)) uncovered a recent decrease in frequency, plummeting from 14.5% (95/657) in 2019 to 2.9% (24/820) in 2022. Weir and Cockerham population differentiation (FST) based on genome-wide single-nucleotide polymorphism (SNP) of 117 selected dogs detected the SNP with the highest FST located in the intron of SOD1 adjacent to the c.118G>A mutation, supporting a selection signature on SOD1. Further genome-wide SNP analyses revealed no obvious changes in inbreeding levels and genetic diversity between the 2019 and 2022 populations. Our study highlights that genetic testing can help inform improved mating choices in breeding programs to reduce the frequency of risk variants and avoid inbreeding. This combined strategy could decrease the genetic risk of canine degenerative myelopathy, a fatal disease, within only a few years.

Two cases of MPXV infection during pregnancy in heterosexual cisgender women without classic cutaneous lesions, Northern California, 2022

As part of an epidemiologic survey, we screened remnant samples collected for STI testing for mpox virus. We identified two cases of presumed MPXV infection in pregnant, heterosexual cisgender women. Here, we describe their pregnancy and birth outcomes. Both patients required induction of labor and experienced labor complicated by chorioamnionitis.

Prevalence of Mpox (Monkeypox) in patients undergoing STI screening in northern California, April-September 2022

BACKGROUND

Despite the sharp increase in mpox (formerly monkeypox) incidence and the wide geographic spread of mpox during the 2022 outbreak, the community prevalence of infection remains poorly characterized. This study is a retrospective epidemiologic survey to estimate mpox prevalence.

METHODS

Samples obtained for sexually transmitted infection (STI) testing from April to September 2022 in the public hospital and clinic system of San Mateo County, California were screened for mpox virus (MPXV) using polymerase chain reaction.

RESULTS

16/1,848 samples from 11/1,645 individuals were positive for MPXV by qPCR. 4/11 individuals with positive MPXV testing were cisgender women, 2 of whom were pregnant at the time of sample collection. Both deliveries were complicated by chorioamnionitis. Anorectal and oropharyngeal samples were the most likely to be positive for MPXV (4/60 anorectal samples and 4/66 oropharyngeal samples compared with 5/1,264 urine samples and 3/445 vaginal samples).

CONCLUSIONS

Our study is one of the first epidemiologic surveys for MPXV infection outside of sexual health/STI clinic settings. Relatively high rates of MPXV from oropharyngeal and anorectal samples reinforces the importance of MPXV testing at various anatomic sites, particularly if patients are presenting with non-lesional symptoms (pharyngitis, proctitis). However, the United States Food and Drug Administration (FDA) has not yet authorized non-lesional MPXV testing. The identification of MPXV in women in our cohort suggests that the rates of mpox in women may have previously been underestimated and highlights the risk of pregnancy complications associated with mpox.

Comparison of Real-Time PCR and Digital PCR for Detection of Plasma Epstein-Barr Virus DNA in Nasopharyngeal Carcinoma

Plasma Epstein-Barr virus (EBV) DNA is an established biomarker for endemic nasopharyngeal carcinoma. However, existing real-time quantitative PCR (qPCR) assays are limited by poor interlaboratory reproducibility. This is a barrier to biomarker integration into staging systems and management. It was hypothesized that EBV digital PCR (dPCR) would have similar sensitivity but improved precision relative to qPCR. Using the World Health Organization EBV standard and patient specimens, the NRG-HN001 BamHI-W qPCR, two commercial EBNA-1 qPCR assays, and two laboratory-developed dPCR assays amplifying the BamHI-W, EBNA-1, and EBER targets were compared. Testing was conducted in the North American reference laboratory for the NRG-HN001 randomized trial. The EBV dPCR assays achieved similar performance compared with qPCR. Although dPCR does not require quantitation standards, different dPCR thresholding algorithms yielded significant qualitative and quantitative variation. This was most evident with low levels of EBV DNA. No-template control-informed thresholding (ddpcRquant) mitigated false-positive/false-negative findings. The NRG-HN001 BamHI-W qPCR and laboratory-developed BamHI-W droplet dPCR offered higher sensitivity, lower limit of blank, higher precision at low plasma EBV DNA levels (≤1500 IU/mL), and higher overall agreement with clinical specimens versus single-copy qPCR/dPCR targets (EBNA-1/EBER). These data confirm the rationale for using the BamHI-W target to define prognostic thresholds and indicate that both qPCR and dPCR methods harmonized to the World Health Organization standard can provide the necessary analytical performance.

Evaluation of a multiplexed oligonucleotide ligation assay for SARS-CoV-2 variant identification

BACKGROUND

SARS-CoV-2 variant surveillance informs vaccine composition and decisions to de-authorize antibody therapies. Though detailed genetic characterization requires whole-genome sequencing, targeted mutation analysis may complement pandemic surveillance efforts.

METHODS

This study investigated the qualitative performance of a multiplex oligonucleotide ligation assay targeting 19 spike mutations using 192 whole genome sequenced upper respiratory samples representing SARS-CoV-2 variants of concern.

RESULTS

Initial valid results were obtained from 95.8% [95% confidence interval (CI): 92.0 - 98.2; 184/192] of samples. All eight invalid samples were valid on repeat testing. When comparing SARS-CoV-2 oligonucleotide ligase assay SARS-CoV-2 variant calls with whole genome sequencing, overall positive percent agreement was 100% (95% CI: 98.1 - 100.0; 192/192), as was the positive and negative percent agreement for each of the tested variants; Gamma, Delta, Omicron BA.1, BA.2, and BA.4/BA.5.

CONCLUSIONS

This multiplexed oligonucleotide ligation assays demonstrated accurate SARS-CoV-2 variant typing compared to whole genome sequencing. Such an approach has the potential to provide improved turnaround compared to sequencing and more detailed mutation coverage than RT-qPCR.

Retrospective Screening of Clinical Samples for Monkeypox Virus DNA, California, USA, 2022

We retrospectively screened oropharyngeal and rectal swab samples originally collected in California, USA, for Chlamydia trachomatis and Neisseria gonorrhoeae testing for the presence of monkeypox virus DNA. Among 206 patients screened, 17 (8%) had samples with detectable viral DNA. Monkeypox virus testing from mucosal sites should be considered for at-risk patients.

mRNA bivalent booster enhances neutralization against BA.2.75.2 and BQ.1.1

The emergence of the highly divergent SARS-CoV-2 Omicron variant has jeopardized the efficacy of vaccines based on the ancestral spike. The bivalent COVID-19 mRNA booster vaccine within the United States is comprised of the ancestral and the Omicron BA.5 spike. Since its approval and distribution, additional Omicron subvariants have been identified with key mutations within the spike protein receptor binding domain that are predicted to escape vaccine sera. Of particular concern is the R346T mutation which has arisen in multiple subvariants, including BA.2.75.2 and BQ.1.1. Using a live virus neutralization assay, we evaluated serum samples from individuals who had received either one or two monovalent boosters or the bivalent booster to determine neutralizing activity against wild-type (WA1/2020) virus and Omicron subvariants BA.1, BA.5, BA.2.75.2, and BQ.1.1. In the one monovalent booster cohort, relative to WA1/2020, we observed a reduction in neutralization titers of 9-15-fold against BA.1 and BA.5 and 28-39-fold against BA.2.75.2 and BQ.1.1. In the BA.5-containing bivalent booster cohort, the neutralizing activity improved against all the Omicron subvariants. Relative to WA1/2020, we observed a reduction in neutralization titers of 3.7- and 4-fold against BA.1 and BA.5, respectively, and 11.5- and 21-fold against BA.2.75.2 and BQ.1.1, respectively. These data suggest that the bivalent mRNA booster vaccine broadens humoral immunity against the Omicron subvariants.

Multiplex Epstein-Barr virus BALF2 genotyping detects high-risk variants in plasma for population screening of nasopharyngeal carcinoma

Background

Epstein-Barr Virus (EBV)-associated nasopharyngeal carcinoma (NPC) exhibits unusual geographic restriction despite ubiquitous lifelong infection. Screening programs can detect most NPC cases at an early stage, but existing EBV diagnostics are limited by false positives and low positive predictive value (PPV), leading to excess screening endoscopies, MRIs, and repeated testing. Recent EBV genome-wide association studies (GWAS) suggest that EBV BALF2 variants account for more than 80% of attributable NPC risk. We therefore hypothesized that high-risk BALF2 variants could be readily detected in plasma for once-lifetime screening triage.

Methods

We designed and validated a multiplex genotyping assay to detect EBV BALF2 polymorphisms in human plasma. Targeted next-generation sequencing was used to validate this assay, conduct association studies with clinical phenotype, and longitudinally genotype plasma to assess within-host haplotype stability. We examined the association between NPC and BALF2 haplotypes in a large non-endemic population and three prior EBV GWAS. Finally, we estimated NPC mortality reduction, resource utilization, and cost-effectiveness of BALF2 variant-informed screening using a previously-validated cohort model.

Results

Following analytical validation, the BALF2 genotyping assay had 99.3% concordance with sequencing in a cohort of 24 NPC cases and 155 non-NPC controls. BALF2 haplotype was highly associated with NPC in this non-endemic population (I613V: odds ratio [OR] 7.9; V317M: OR 178.8). No other candidate BALF2 polymorphisms were significantly associated with NPC or hematologic disorders.

Longitudinal genotyping revealed 97.8% within-host haplotype concordance, indicative of lifelong latent infection. In a meta-analysis of 755 NPC cases and 981 non-NPC controls, BALF2 I613V and V317M were significantly associated with NPC in both endemic and non-endemic populations.

Modeled variant-informed screening strategies achieved a 46% relative increase in PPV with 7% decrease in effective screening sensitivity, thereby averting nearly half of screening endoscopies/MRIs among endemic populations in east/southeast Asia.

Conclusions

EBV BALF2 haplotypes are temporally stable within hosts and can be readily detected in plasma via an inexpensive multiplex genotyping assay that offers near-perfect sequencing concordance. In endemic and non-endemic populations, I613V and V317M were highly associated with NPC and could be leveraged to develop variant-informed screening programs that mitigate false positives with small reductions in screening sensitivity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12943-022-01625-6.

Characterizing the Severity of SARS-CoV-2 Variants at a Single Pediatric Center

Since March 2020, SARS-CoV-2 has plagued the world with COVID-19 and individuals of all ages have experienced varying symptoms of disease. Older adults were experiencing more severe disease compared to children and were prioritized by vaccination efforts. While biologic therapies and vaccinations were implemented, there were changes in public health restrictions with subsequent surges resulting in more infected children. During these surges there was a rise of different SARS-CoV-2 variants with the dominant variant initially alpha (B.1.1.7 and other Pango lineages) and epsilon (B.1.427/B.1.429) in early 2021 and a dramatic shift to delta (B.1.617.2 and other Pango lineages) by mid-summer 2021. In this study we aimed to characterize the clinical severity and host factors associated with disease by SARS-CoV-2 variant and evaluate if there are differences in disease severity by circulating variant. We retrospectively included all individuals 0–25 years of age who presented to our center and had a positive SARS-CoV-2 RT-PCR, SARS-CoV-2 variant mutation testing, and documented clinical notes from 1 January 2021 through 31 December 2021. We identified 745 individuals who met inclusion criteria and found the delta variant was associated with severe/critical disease compared to the other variants studied. The results of the model showed that underlying respiratory disease and diabetes were risk factors for progression to severe disease. These insights are important when evaluating public health measures and treatment options for children as more variants arise.

Long-term safety and effectiveness of linagliptin by baseline body mass index in Japanese patients with type 2 diabetes: a 3-year post-marketing surveillance study

BACKGROUND

A recent 3-year post-marketing surveillance (PMS) study reaffirmed the safety and effectiveness of linagliptin in linagliptin-naïve Japanese patients with type 2 diabetes (T2D). We present further analyses from this study by body mass index (BMI).

RESEARCH DESIGN AND METHODS

Safety and effectiveness were assessed across BMI subgroups (<25, 25 to <30, and ≥30 kg/m²).

RESULTS

Data were available for 876, 566, and 201 patients in the BMI subgroups, respectively. Incidence of adverse drug reactions [ADR] with linagliptin was 11.42%, 11.31%, 10.45%, respectively. The most common ADR of special interest was hepatic disorders (n [%]: 6 [0.68], 7 [1.24] and 3 [1.49], respectively). Additional use of glucose-lowering drugs (GLDs) increased with BMI (15.0%, 19.1%, 24.4% of patients; P < 0.001). In the overall population, a sustained decrease in HbA1c was observed in all BMI subgroups. In patients receiving linagliptin with no additional GLDs, changes in HbA1c were -0.58%±0.04, -0.62%±0.04, and -0.77%±0.11.

CONCLUSIONS

In this study of linagliptin in Japanese patients with T2D, across BMI subgroups no new safety concerns were observed. The proportion of patients with additional GLD use increased with baseline BMI. Decreases in HbA1c were observed in all subgroups, including in patients with no additional GLD use.

CLINICALTRIALS.GOV

NCT01650259.

SARS-CoV-2 Nucleocapsid Plasma Antigen for Diagnosis and Monitoring of COVID-19

BACKGROUND

Detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid antigen in blood has been described, but the diagnostic and prognostic role of antigenemia is not well understood. This study aimed to determine the frequency, duration, and concentration of nucleocapsid antigen in plasma and its association with coronavirus disease 2019 (COVID-19) severity.

METHODS

We utilized an ultrasensitive electrochemiluminescence immunoassay targeting SARS-CoV-2 nucleocapsid antigen to evaluate 777 plasma samples from 104 individuals with COVID-19. We compared plasma antigen to respiratory nucleic acid amplification testing (NAAT) in 74 individuals with COVID-19 from samples collected ±1 day of diagnostic respiratory NAAT and in 52 SARS-CoV-2-negative individuals. We used Kruskal-Wallis tests, multivariable logistic regression, and mixed-effects modeling to evaluate whether plasma antigen concentration was associated with disease severity.

RESULTS

Plasma antigen had 91.9% (95% CI 83.2%-97.0%) clinical sensitivity and 94.2% (84.1%-98.8%) clinical specificity. Antigen-negative plasma samples belonged to patients with later respiratory cycle thresholds (Ct) when compared with antigen-positive plasma samples. Median plasma antigen concentration (log10 fg/mL) was 5.4 (interquartile range 3.9-6.0) in outpatients, 6.0 (5.4-6.5) in inpatients, and 6.6 (6.1-7.2) in intensive care unit (ICU) patients. In models adjusted for age, sex, diabetes, and hypertension, plasma antigen concentration at diagnosis was associated with ICU admission [odds ratio 2.8 (95% CI 1.2-6.2), P=.01] but not with non-ICU hospitalization. Rate of antigen decrease was not associated with disease severity.

CONCLUSIONS

SARS-CoV-2 plasma nucleocapsid antigen exhibited comparable diagnostic performance to upper respiratory NAAT, especially among those with late respiratory Ct. In addition to currently available tools, antigenemia may facilitate patient triage to optimize intensive care utilization.

Effect of adding magnifying BLI, magnifying NBI, and iodine staining to white light imaging in diagnosis of early esophageal cancer

Background and study aims  We investigated the effect of adding magnifying blue laser imaging (BLI), magnifying narrow-band imaging (NBI), and iodine staining to white light imaging in diagnosis of early esophageal squamous cell carcinoma (EESCC) in high-risk patients. Patients and methods  Between May 2013 and March 2016, two parallel prospective cohorts of patients received either primary WLI followed by NBI-magnifying endoscopy (ME) or primary WLI followed by BLI-ME, were studied. At the end of screening, both groups underwent iodine staining. The percentage of patients with newly detected esophageal malignant lesions in each group and the diagnostic ability of image-enhanced endoscopy (IEE)-ME were evaluated. Results  There are 258 patients assigned to the NBI-ME group and 254 patients assigned to the BLI-ME group. The percentage of patients with one or more malignant lesions detected in the WLI + NBI-ME examination was similar in the WLI + BLI-ME examination (15 of 258 patients or 5.81 % vs. 14 of 254 patients or 5.51 %). However, four of 19 lesions in the NBI-ME group and six of 21 lesions in the BLI-ME group were overlooked and were detected by iodine staining. NBI-ME and BLI-ME showed similar accuracy in differentiation of cancerous lesions from non-cancerous lesions in diagnosis of EESCC (NBI/BLI: sensitivity, 87.5/89.5; specificity, 78.9/76.6; accuracy, 80.8/79.5; positive predictive value, 53.8/53.1; negative predictive value, 95.7/96.1). Conclusions  Both NBI and BLI were useful for detection of EESCC. However, because some lesions were overlooked by even NBI and BLI, high-risk patients may benefit from use of iodine staining during endoscopic screening of EESCC (UMIN000023596).

Safety and tolerability of linagliptin in Asians with type 2 diabetes: a pooled analysis of 4457 patients from 21 randomized, double-blind, placebo-controlled clinical trials

BACKGROUND

Safety and tolerability of glucose-lowering drugs is a key consideration for use in type 2 diabetes (T2D). We evaluated the safety and tolerability of the dipeptidyl peptidase-4 inhibitor linagliptin in Asian patients with T2D.

RESEARCH DESIGN AND METHODS

This was a post-hoc, descriptive pooled analysis of 21 randomized, double-blind, placebo-controlled clinical trials of linagliptin in T2D patients lasting ≤52 weeks. We evaluated adverse events (AEs) and laboratory parameters in Asian participants living in Asia, both overall and in the East Asian subgroup.

RESULTS

This analysis included 4457 Asian patients overall (2712 receiving linagliptin; 1745 receiving placebo) and 3057 (68.6%) East Asians. AEs were reported in 1510 (55.7%) Asian patients receiving linagliptin and 1032 (59.1%) receiving placebo but were considered drug-related in only 13.0% of each group. Serious AEs occurred in 109 (4.0%) linagliptin patients and 90 (5.2%) placebo patients. The most common AEs were nasopharyngitis (6.4% linagliptin, 7.3% placebo), upper respiratory tract infection (5.7% linagliptin, 6.5% placebo), and hypoglycemia (7.3% linagliptin, 6.3% placebo). One linagliptin patient had pancreatitis; none had bullous pemphigoid. No clinically relevant mean changes in laboratory parameters occurred. These findings were consistent in East Asians.

CONCLUSIONS

Linagliptin is well tolerated in Asian T2D patients, including East Asians, with low risk for AEs.

SARS-CoV-2 Neutralization Resistance Mutations in Patient with HIV/AIDS, California, USA

We report persistent severe acute respiratory syndrome coronavirus 2 infection in a patient with HIV/AIDS; the virus developed spike N terminal domain and receptor binding domain neutralization resistance mutations. Our findings suggest that immunocompromised patients can harbor emerging variants of severe acute respiratory syndrome coronavirus 2.

Diagnostic Accuracy of Diastolic Fractional Flow Reserve for Functional Evaluation of Coronary Stenosis

Background

In the resting conditions, narrowing the window of coronary pressure measurements from the whole cardiac cycle to diastole improves diagnostic performance of coronary pressure–derived physiological index. However, whether this also applies to the hyperemic conditions has not yet been thoroughly evaluated.

Objectives

The purpose of this study was to assess whether diastolic fractional flow reserve (diastolic FFR) has better diagnostic performance in identifying ischemia-causing coronary lesions than conventional FFR in a prospective, multicenter, and independent core laboratory–based environment.

Methods

In this prospective multicenter registry at 29 Japanese centers, we compared the diagnostic performance of FFR, diastolic FFR, resting distal to aortic coronary pressure (Pd/Pa), and diastolic pressure ratio (dPR) using myocardial perfusion scintigraphy (MPS) as the reference standard in 378 patients with single-vessel coronary disease.

Results

Inducible myocardial ischemia was found on MPS in the relevant myocardial territory of the target vessel in 85 patients (22%). In the receiver-operating curve analyses, diastolic FFR had comparable area under the curve (AUC) compared with FFR (AUC_{diastolic FFR}: 0.66; 95% confidence interval [CI]: 0.58-0.73, vs AUC_FFR: 0.66; 95% CI: 0.58-0.74, P = 0.624). FFR and diastolic FFR showed significantly larger AUCs than resting Pd/Pa (0.62; 95% CI: 0.54-0.70; P = 0.033 and P = 0.046) but did not show significantly larger AUCs than dPR (0.62; 95% CI: 0.55-0.70; P = 0.102 and P = 0.113).

Conclusions

Diastolic FFR showed a similar diagnostic performance to FFR as compared with MPS. This result reaffirms the use of FFR as the most accurate invasive physiological lesion assessment. (Diagnostic accuracy of diastolic fractional flow reserve (d-FFR) for functional evaluation of coronary stenosis; UMIN000015906)

Multiplex SARS-CoV-2 Genotyping Reverse Transcriptase PCR for Population-Level Variant Screening and Epidemiologic Surveillance

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with concerning phenotypic mutations is of public health interest. Genomic surveillance is an important tool for a pandemic response, but many laboratories do not have the resources to support population-level sequencing. We hypothesized that a nucleic acid amplification test (NAAT) to genotype mutations in the viral spike protein could facilitate high-throughput variant surveillance. We designed and analytically validated a one-step multiplex allele-specific reverse transcriptase PCR (RT-qPCR) to detect three nonsynonymous spike protein mutations (L452R, E484K, N501Y). Assay specificity was validated with next-generation whole-genome sequencing. We then screened a large cohort of SARS-CoV-2-positive specimens from our San Francisco Bay Area population. Between 1 December 2020 and 1 March 2021, we screened 4,049 unique infections by genotyping RT-qPCR, with an assay failure rate of 2.8%. We detected 1,567 L452R mutations (38.7%), 34 N501Y mutations (0.84%), 22 E484K mutations (0.54%), and 3 (0.07%) E484K plus N501Y mutations. The assay had perfect (100%) concordance with whole-genome sequencing of a validation subset of 229 specimens and detected B.1.1.7, B.1.351, B.1.427, B.1.429, B.1.526, and P.2 variants, among others. The assay revealed the rapid emergence of the L452R variant in our population, with a prevalence of 24.8% in December 2020 that increased to 62.5% in March 2021. We developed and clinically implemented a genotyping RT-qPCR to conduct high-throughput SARS-CoV-2 variant screening. This approach can be adapted for emerging mutations and immediately implemented in laboratories already performing NAAT worldwide using existing equipment, personnel, and extracted nucleic acid.

Multiplex SARS-CoV-2 Genotyping Reverse Transcriptase PCR for Population-Level Variant Screening and Epidemiologic Surveillance

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with concerning phenotypic mutations is of public health interest. Genomic surveillance is an important tool for a pandemic response, but many laboratories do not have the resources to support population-level sequencing. We hypothesized that a nucleic acid amplification test (NAAT) to genotype mutations in the viral spike protein could facilitate high-throughput variant surveillance. We designed and analytically validated a one-step multiplex allele-specific reverse transcriptase PCR (RT-qPCR) to detect three nonsynonymous spike protein mutations (L452R, E484K, N501Y). Assay specificity was validated with next-generation whole-genome sequencing. We then screened a large cohort of SARS-CoV-2-positive specimens from our San Francisco Bay Area population. Between 1 December 2020 and 1 March 2021, we screened 4,049 unique infections by genotyping RT-qPCR, with an assay failure rate of 2.8%. We detected 1,567 L452R mutations (38.7%), 34 N501Y mutations (0.84%), 22 E484K mutations (0.54%), and 3 (0.07%) E484K plus N501Y mutations. The assay had perfect (100%) concordance with whole-genome sequencing of a validation subset of 229 specimens and detected B.1.1.7, B.1.351, B.1.427, B.1.429, B.1.526, and P.2 variants, among others. The assay revealed the rapid emergence of the L452R variant in our population, with a prevalence of 24.8% in December 2020 that increased to 62.5% in March 2021. We developed and clinically implemented a genotyping RT-qPCR to conduct high-throughput SARS-CoV-2 variant screening. This approach can be adapted for emerging mutations and immediately implemented in laboratories already performing NAAT worldwide using existing equipment, personnel, and extracted nucleic acid.

High Frequency of SARS-CoV-2 RNAemia and Association With Severe Disease

Background

Detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in blood, also known as RNAemia, has been reported, but its prognostic implications are poorly understood. This study aimed to determine the frequency of SARS-CoV-2 RNA in plasma and its association with coronavirus disease 2019 (COVID-19) clinical severity.

Methods

An analytical cross-sectional study was performed in a single-center tertiary care institution and included consecutive inpatients and outpatients with confirmed COVID-19. The prevalence of SARS CoV-2 RNAemia and the strength of its association with clinical severity variables were examined and included intensive care unit (ICU) admission, invasive mechanical ventilation, and 30-day all-cause mortality.

Results

Paired nasopharyngeal and plasma samples were included from 85 patients. The median age was 55 years, and individuals with RNAemia were older than those with undetectable SARS-CoV-2 RNA in plasma (63 vs 50 years; P = .04). Comorbidities were frequent including obesity (37.6%), hypertension (30.6%), and diabetes mellitus (22.4%). RNAemia was detected in 28/85 (32.9%) of patients, including 22/28 (78.6%) who required hospitalization. In models adjusted for age, RNAemia was detected more frequently in individuals who developed severe disease including ICU admission (32.1 vs 14.0%; P = .04) and invasive mechanical ventilation (21.4% vs 3.5%; P = .02). All 4 deaths occurred in individuals with detectable RNAemia. An additional 121 plasma samples from 28 individuals with RNAemia were assessed longitudinally, and RNA was detected for a maximum duration of 10 days.

Conclusions

This study demonstrated a high proportion of SARS-CoV-2 RNAemia, and an association between RNAemia and clinical severity suggesting the potential utility of plasma viral testing as a prognostic indicator for COVID-19.

Effects of anti-diabetes medications on cardiovascular and kidney outcomes in Asian patients with type 2 diabetes: a rapid evidence assessment and narrative synthesis

BACKGROUND

The cardiovascular and kidney safety of glucose-lowering drugs is a key concern in type 2 diabetes (T2D). We evaluated cardiorenal outcomes with glucose-lowering drugs in Asian patients, who comprise over half of T2D cases globally.

RESEARCH DESIGN AND METHODS

A rapid evidence assessment was conducted for phase III or IV, double-blind, randomized clinical trials of glucose-lowering drugs reporting cardiovascular or kidney outcomes for Asian T2D patients (Embase, Medline, Cochrane Library databases: 1 January 2008-14 June 2020).

RESULTS

Fifty-four publications reported exploratory data for Asians from 18 trials of dipeptidyl peptidase-4 (DPP-4) inhibitors, sodium-glucose co-transporter-2 (SGLT2) inhibitors, glucagon-like peptide-1 (GLP-1) receptor agonists, and insulin analogs. SGLT2 inhibitors and several GLP-1 receptor agonists were associated with reduced cardiovascular risk in Asian T2D patients, while DPP-4 inhibitors exhibited cardiovascular safety. SGLT2 inhibitors also appeared to reduce renal risk; however, kidney outcomes were lacking for DPP-4 inhibitors other than linagliptin and GLP-1 receptor agonists in Asian patients. Insulin data were inconclusive as the only trial conducted used different types of insulin as both treatment and comparator.

CONCLUSIONS

Cardiorenal outcomes with glucose-lowering drugs in Asian T2D patients were similar to outcomes in the overall multinational cohorts of these trials. DPP-4 inhibitors appear to demonstrate cardiovascular safety in Asians, while SGLT2 inhibitors and some GLP-1 receptor agonists may reduce cardiorenal and cardiovascular risk, respectively.

Plasma as an alternative COVID-19 diagnostic specimen in a hospitalized patient negative for SARS-CoV-2 by nasopharyngeal swab

We present the case of an inpatient with pneumonia and repeatedly negative nasopharyngeal SARS-CoV-2 testing. In such challenging cases, alternative diagnostic options include lower respiratory tract and plasma SARS-CoV-2 RNA testing, of which the latter may be particularly useful where bronchoscopy is deferred due to clinical factors or transmission risk.

Defining the features and duration of antibody responses to SARS-CoV-2 infection associated with disease severity and outcome

SARS-CoV-2-specific antibodies, particularly those preventing viral spike receptor binding domain (RBD) interaction with host angiotensin-converting enzyme 2 (ACE2) receptor, can neutralize the virus. It is, however, unknown which features of the serological response may affect clinical outcomes of COVID-19 patients. We analyzed 983 longitudinal plasma samples from 79 hospitalized COVID-19 patients and 175 SARS-CoV-2-infected outpatients and asymptomatic individuals. Within this cohort, 25 patients died of their illness. Higher ratios of IgG antibodies targeting S1 or RBD domains of spike compared to nucleocapsid antigen were seen in outpatients who had mild illness versus severely ill patients. Plasma antibody increases correlated with decreases in viral RNAemia, but antibody responses in acute illness were insufficient to predict inpatient outcomes. Pseudovirus neutralization assays and a scalable ELISA measuring antibodies blocking RBD-ACE2 interaction were well correlated with patient IgG titers to RBD. Outpatient and asymptomatic individuals' SARS-CoV-2 antibodies, including IgG, progressively decreased during observation up to five months post-infection.

SARS-CoV-2 Antibody Responses Correlate with Resolution of RNAemia But Are Short-Lived in Patients with Mild Illness

SARS-CoV-2-specific antibodies, particularly those preventing viral spike receptor binding domain (RBD) interaction with host angiotensin-converting enzyme 2 (ACE2) receptor, could offer protective immunity, and may affect clinical outcomes of COVID-19 patients. We analyzed 625 serial plasma samples from 40 hospitalized COVID-19 patients and 170 SARS-CoV-2-infected outpatients and asymptomatic individuals. Severely ill patients developed significantly higher SARS-CoV-2-specific antibody responses than outpatients and asymptomatic individuals. The development of plasma antibodies was correlated with decreases in viral RNAemia, consistent with potential humoral immune clearance of virus. Using a novel competition ELISA, we detected antibodies blocking RBD-ACE2 interactions in 68% of inpatients and 40% of outpatients tested. Cross-reactive antibodies recognizing SARS-CoV RBD were found almost exclusively in hospitalized patients. Outpatient and asymptomatic individuals' serological responses to SARS-CoV-2 decreased within 2 months, suggesting that humoral protection may be short-lived.

Cost-Effectiveness Analysis of Linagliptin in Japan Based on Results from the Asian Subpopulation in the CARMELINA® Trial

INTRODUCTION

We evaluated the cost-effectiveness of linagliptin in Japan by estimating the lifetime outcome based on clinical event rates from the Asian subpopulation of the CARMELINA trial. In CARMELINA, linagliptin added to standard of care (SoC) versus SoC demonstrated noninferiority with regard to risk of composite cardiovascular (CV) outcome in patients with type 2 diabetes at high risk of CV and kidney events. Issues resulting from conducting a cost-effectiveness analysis using data from a clinical noninferiority study were also investigated.

METHODS

A microsimulation model was used to evaluate linagliptin/SoC versus SoC in terms of direct costs and quality-adjusted life years (QALYs) from a Japanese public healthcare payer's perspective. Cost data were obtained from recent Japanese publications. The time horizon was defined as lifetime, and the discount rate for costs and effectiveness was 2% per year. One-way and probabilistic sensitivity analyses were performed.

RESULTS

In the base case analysis, and taking medical history into account, the incremental effectiveness of linagliptin/SoC versus SoC was 1.34 QALYs, and the incremental cost for linagliptin was - 545,319 yen. In the one-way sensitivity analysis, the parameter which most affected the results was the hazard ratio for renal failure of linagliptin/SoC compared with SoC. The probabilistic sensitivity analysis showed that the probability of reduced costs and increased effectiveness (dominant) was 48%. Assuming an incremental cost-effectiveness ratio (ICER) threshold of 5 million yen, the probability that the ICER was below the threshold was 89% for linagliptin/SoC compared with SoC.

CONCLUSIONS

This evaluation, using Asian subpopulation data from the CARMELINA trial, suggested that the cost-effectiveness of linagliptin for a lifetime outcome was favourable in Japan. However, the results must be interpreted cautiously because of the noninferiority trial data source, which might cause ICER variations for each parameter.

Safety and tolerability of empagliflozin and linagliptin combination therapy in patients with type 2 diabetes mellitus: a pooled analysis of data from five randomized, controlled clinical trials

OBJECTIVES

The fixed-dose combination of empagliflozin and linagliptin, two glucose-lowering drugs prescribed for type 2 diabetes mellitus, has demonstrated good tolerability in phase III clinical trials. To further evaluate the safety profile of this combination, the data from these trials were pooled and analyzed.

METHODS

This was a post-hoc pooled analysis of five randomized, double-blind, clinical trials of the empagliflozin/linagliptin fixed-dose combination. Data for adverse events and laboratory parameters were evaluated.

RESULTS

The analysis included 2895 patients: 1410, 1015, and 470 receiving the empagliflozin/linagliptin combination, empagliflozin monotherapy, and linagliptin monotherapy, respectively. Overall, the incidence of adverse events with the empagliflozin/linagliptin combination was similar to that with empagliflozin or linagliptin alone. Fewer than 2% of patients experienced hypoglycemia, and its incidence was similar across treatment groups. Genital infections occurred in more patients receiving empagliflozin/linagliptin (3.0%) or empagliflozin monotherapy (5.1%) than in those receiving linagliptin monotherapy (1.9%). No cases of Fournier's gangrene, diabetic ketoacidosis, or pemphigoid occurred, and no clinically relevant mean changes in laboratory parameters were noted.

CONCLUSION

The safety profile of the fixed-dose combination of empagliflozin and linagliptin was similar to the individual monotherapies. No new safety signals were identified.

Capturing Differential Allele-Level Expression and Genotypes of All Classical HLA Loci and Haplotypes by a New Capture RNA-Seq Method

The highly polymorphic human major histocompatibility complex (MHC) also known as the human leukocyte antigen (HLA) encodes class I and II genes that are the cornerstone of the adaptive immune system. Their unique diversity (>25,000 alleles) might affect the outcome of any transplant, infection, and susceptibility to autoimmune diseases. The recent rapid development of new next-generation sequencing (NGS) methods provides the opportunity to study the influence/correlation of this high level of HLA diversity on allele expression levels in health and disease. Here, we describe the NGS capture RNA-Seq method that we developed for genotyping all 12 classical HLA loci (HLA-A, HLA-B, HLA-C, HLA-DPA1, HLA-DPB1, HLA-DQA1, HLA-DQB1, HLA-DRA, HLA-DRB1, HLA-DRB3, HLA-DRB4, and HLA-DRB5) and assessing their allelic imbalance by quantifying their allele RNA levels. This is a target enrichment method where total RNA is converted to a sequencing-ready complementary DNA (cDNA) library and hybridized to a complex pool of RNA-specific HLA biotinylated oligonucleotide capture probes, prior to NGS. This method was applied to 161 peripheral blood mononuclear cells and 48 umbilical cord blood cells of healthy donors. The differential allelic expression of 10 HLA loci (except for HLA-DRA and HLA-DPA1) showed strong significant differences (P < 2.1 × 10-15). The results were corroborated by independent methods. This newly developed NGS method could be applied to a wide range of biological and medical questions including graft rejections and HLA-related diseases.

Long-Term Safety and Effectiveness of Linagliptin in Japanese Patients with Type 2 Diabetes and Renal Dysfunction: a Post-Marketing Surveillance Study

INTRODUCTION

International clinical trials have shown that linagliptin significantly improves glycemic control and can be used at a single dose regardless of renal function in patients with type 2 diabetes (T2D). However, to date, no studies have evaluated the use of linagliptin in Japanese patients with T2D by renal function in routine clinical care.

METHODS

This was a subgroup analysis of data from a prospective observational post-marketing surveillance (PMS) study of linagliptin conducted in Japan that evaluated the safety and effectiveness of linagliptin in routine clinical care for 3 years in Japanese patients with T2D. The subgroup analysis examined the patient population of this PMS study according to renal function using estimated glomerular filtration rate (eGFR) data. The incidence of linagliptin-related adverse events (adverse drug reactions [ADRs]) was the primary endpoint, and the change in glycated hemoglobin (HbA1c) from baseline to last observation was the secondary endpoint.

RESULTS

Of the 2235 patients included in the safety analysis, eGFR was ≥ 90 mL/min/1.73 m² (defined as group G1) in 16.9% (n = 377), ≥ 60 to < 90 mL/min/1.73 m² (group G2) in 44.5% (n = 995), ≥  30 to < 60 mL/min/1.73 m² (group G3) in 21.7% (n = 486),  ≥ 15 to < 30 mL/min/1.73 m² (group G4) in 2.6% (n = 58) and < 15 mL/min/1.73 m² (group G5) in 1.7% (n = 37). No eGFR data were available for 12.6% (n = 282) of patients. In these GFR groups, the incidence of ADRs with linagliptin was 6.9% in group G1, 11.1% in group G2, 13.8% in group G3, 15.5% in group G4 and 16.2% in group G5; the change in HbA1c from baseline to the last observation was - 1.11, - 0.64, - 0.35, - 0.46 and - 0.54% in the respective subgroups.

CONCLUSIONS

Long-term linagliptin use showed sustained improvements in glycemic control with no new safety concerns regardless of renal function.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT01650259).

FUNDING

This study was funded by Nippon Boehringer Ingelheim Co., Ltd. and Eli Lilly Japan K.K.

Long-Term Safety and Effectiveness of Linagliptin in Japanese Patients with Type 2 Diabetes Mellitus: A 3-Year Post-Marketing Surveillance Study

INTRODUCTION

Clinical trials of linagliptin in Japanese patients conducted to date have had limited observational periods; therefore, there is a need for additional longer-term real-world data. The aim of this study was to investigate the long-term safety and effectiveness of linagliptin in routine clinical practice.

METHODS

This was a prospective, observational, post-marketing surveillance study conducted over 156 weeks in patients with type 2 diabetes mellitus who started linagliptin monotherapy. The primary endpoint was the incidence of adverse drug reactions (ADRs). The secondary endpoint was the change in glycated hemoglobin (HbA1c) from baseline to last available observation. Other effectiveness endpoints included the change in HbA1c and change in fasting plasma glucose (FPG) from baseline to week 26 and over the course of the treatment period.

RESULTS

Overall, 2235 and 2054 patients were included in the safety and effectiveness analysis sets, respectively. Patients were mostly male (58.4%), and the mean age was 66.7 years. The incidence of ADRs was 10.7% (n = 240). The most frequent ADRs according to MedDRA preferred terms were diabetes mellitus (n = 35 patients, 1.6%), constipation (n = 21, 0.9%), diabetes mellitus inadequate control (n = 13, 0.6%) and hypertension (n = 13, 0.6%). The mean change in HbA1c from baseline to last observation was - 0.67% [standard deviation (SD) 1.27%, 95% confidence interval - 0.72, - 0.61]. At week 26, HbA1c and FPG showed mean ± SD changes from baseline of - 0.73 ± 1.20% and - 21.02 ± 44.33 mg/dL, respectively, that were sustained until week 156.

CONCLUSIONS

In Japanese patients with type 2 diabetes mellitus, linagliptin produced sustained reductions in HbA1c and had a safety profile consistent with the established safety profile of linagliptin.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT01650259).

Probable progressive multifocal leukoencephalopathy-immune reconstitution inflammatory syndrome with immunosuppressant dose reduction following lung transplantation: a case report and literature review

BACKGROUND

Progressive multifocal leukoencephalopathy (PML) is a rapidly developing demyelinating disease in the cerebral white matter and is often caused by JC polyomavirus (JCV). PML after lung transplantation is rare and has a poor prognosis, with no established therapies. Reducing the patient's immunosuppressant doses, thereby restoring immunity, could be used to treat PML. However, some patients develop immune reconstitution inflammatory syndrome (IRIS) with this treatment, an immune-induced inflammatory response to JCV that results in serious neuronal damage. We herein report a case of a 60-year-old female who suffered from PML 5 years after lung transplantation, had worsened brain lesions thought to be related to PML-IRIS at the time of immunosuppressant reduction, and missed treatment opportunities.

CASE PRESENTATION

A 60-year-old female developed PML 5 years after lung transplantation. Fluid-attenuated inversion recovery and diffusion-weighted brain magnetic resonance imaging (MRI) revealed multiple high-signal lesions, mainly in the cerebral white matter. Polymerase chain reaction found 0.32 million copies/mL of JCV in the cerebrospinal fluid. Thus, she was given a diagnosis of PML. Mycophenolate mofetil and tacrolimus dosages were reduced, and CD4-positive cell counts and the blood concentration of each immunosuppressant were monitored. Mefloquine was also orally administered at a daily dose of 275 mg for 3 days and was then administered at a dose of 275 mg per week. Although the patient's CD4-positive cell counts increased and her immune system recovered, her symptoms and brain MRI findings worsened. We suspected PML progression or a transition to PML-IRIS. Steroid pulse therapy to suppress the inflammatory lesions was not possible but was retrospectively indicated. The patient rapidly began to exhibit akinetic mutism and died 4 months after the onset of neurologic symptoms.

CONCLUSIONS

When neurologic symptoms and abnormal brain MRI findings are noted during immune recovery, it is often difficult to distinguish between progressed PML and PML-IRIS. However, the pathogenesis of brain lesions usually involves inflammation and immune-reactive mechanisms for JCV. Steroid pulse therapy, which can reduce inflammation, should thus be administered in organ transplantation cases with differential diagnoses including PML-IRIS.

GDF-15, a mitochondrial disease biomarker, is associated with the severity of multiple sclerosis

GDF-15, a member of the transforming growth factor beta superfamily, regulates inflammatory and apoptotic pathways in various diseases, such as heart failure, kidney dysfunction, and cancer. We aimed to clarify potentially confounding variables affecting GDF-15 and demonstrate its utility as a mitochondrial biomarker using serum samples from 15 patients with mitochondrial diseases (MD), 15 patients with limbic encephalitis (LE), 10 patients with multiple sclerosis/neuromyelitis optica spectrum disorders (MS/NMOSD), and 19 patients with amyotrophic lateral sclerosis (ALS). GDF-15 and FGF-21 were significantly elevated in MD. GDF-15 and FGF-21 showed a good correlation in MD but not in LE, MS, and ALS. GDF-15 was potentially influenced by age in LE, MS/NMOSD, and ALS but not in MD. FGF-21 was not correlated with age in MS/NMOSD, ALS, LE, and MD. GDF-15 was not correlated with clinical features in LE or BMI or body weight in ALS. GDF-15 positively correlated with the Expanded Disability Status Scale (EDSS) in MS/NMOSD, while EDSS showed no correlation with age. In conclusion, the results revealed that GDF-15 may be influenced by EDSS in MS/NMOPSD and by age in LE, MS/NMOSD, and ALS but not in MD. Mitochondrial damage in MS/NMOSD is a potentially confounding variable affecting GDF-15.

Mapping and definition of HLA class I and II serologic epitopes using an unbiased reverse engineering strategy

Current models describing HLA epitopes are both theoretical and empirical. Each has limitations yielding discordant results and increasingly complex modeling. The models make a priori assumptions that epitopes must be present only on the mature protein, solvent accessible, on the 'top' (peptide binding surface) of the molecule, restricted to the same class as the antibody, and in the same position on the target allele if reactive to more than one locus. Results obtained counter to these assumptions are routinely discounted. For the 17th International Histocompatibility and Immunogenetics Workshop, we developed a reverse engineering algorithm to define epitopes without these assumptions on a cohort of 332 primary transplant pairs. Complete NGS typing of the transcribed (including leader) genomic DNA for 11 HLA loci of donor and recipient and DSA assignment by single antigen beads was performed. Our results show that, when grouped by 16 class I and II allele specific DSA, uniform clusters and 172 specific amino acid target epitopes are recognized by recipients despite originating from disparate HLA pairs. Data also show that these targets can be in the leader, alpha 3, transmembrane and cytoplasmic domains, thus calling into question current assumptions regarding immunogenic epitopes. Comparisons of amino acid epitopes defined by the Terasaki and Duquesnoy groups (TerEp and EpRegistry) are given.

A reverse-engineering strategy utilizing the integration of single antigen beads and NGS HLA genotypes to detect potential antibody inducing epitopes

Central to the idea of antibody recognition is some degree of foreignness of the target antigen compared to the antibody producer. Epitopes are distinct regions on an antigen to which antibody can be elicited and bound. However, for HLA antigens, there is no consensus definition of what represents the minimal functional immunogenic unit of dissimilarity. To assess this in an unbiased way, we developed a reverse engineering software strategy based on donor specific antibodies defined by single antigen beads and full length genomic high resolution HLA typing by NGS of recipients and donors (332 transplant pairs). Starting with the ATG of Exon 1 and moving stepwise one amino acid at a time for each of the following triplets, the algorithm compared every possible amino acid triplet of the recipient and donor for 11 loci (A, B, C, DRB1, DRB3, DRB4, DRB5, DQA1, DQB1, DPA1, DPB1). Results were agnostic with respect to HLA class, not restricted to just the mature protein, and not influenced by existing maps (e.g., IMGT, or epitope models). We also developed web-based functions in the 17th IHIWS database to collect the unbiased triplets so that we could group the transplant pairs with the same donor specific antibodies and find shared triplets within the groups as potential core or essential epitopes that trigger the antibody formation. Profiling the pairs where the same DSA was identified led to identification of discrete amino acid triplets shared among the pairs irrespective of HLA match. The potential epitopes were mapped onto the 3D protein structure for reference.

Quality control project of NGS HLA genotyping for the 17th International HLA and Immunogenetics Workshop

The 17th International HLA and Immunogenetics Workshop (IHIW) organizers conducted a Pilot Study (PS) in which 13 laboratories (15 groups) participated to assess the performance of the various sequencing library preparation protocols, NGS platforms and software in use prior to the workshop. The organizers sent 50 cell lines to each of the 15 groups, scored the 15 independently generated sets of NGS HLA genotyping data, and generated "consensus" HLA genotypes for each of the 50 cell lines. Proficiency Testing (PT) was subsequently organized using four sets of 24 cell lines, selected from 48 of 50 PS cell lines, to validate the quality of NGS HLA typing data from the 34 participating IHIW laboratories. Completion of the PT program with a minimum score of 95% concordance at the HLA-A, HLA-B, HLA-C, HLA-DRB1 and HLA-DQB1 loci satisfied the requirements to submit NGS HLA typing data for the 17th IHIW projects. Together, these PS and PT efforts constituted the 17th IHIW Quality Control project. Overall PT concordance rates for HLA-A, HLA-B, HLA-C, HLA-DPA1, HLA-DPB1, HLA-DQA1, HLA-DQB1, HLA-DRB1, HLA-DRB3, HLA-DRB4 and HLA-DRB5 were 98.1%, 97.0% and 98.1%, 99.0%, 98.6%, 98.8%, 97.6%, 96.0%, 99.1%, 90.0% and 91.7%, respectively. Across all loci, the majority of the discordance was due to allele dropout. The high cost of NGS HLA genotyping per experiment likely prevented the retyping of initially failed HLA loci. Despite the high HLA genotype concordance rates of the software, there remains room for improvement in the assembly of more accurate consensus DNA sequences by NGS HLA genotyping software.

Next-generation HLA typing of 382 International Histocompatibility Working Group reference B-lymphoblastoid cell lines: Report from the 17th International HLA and Immunogenetics Workshop

Extended molecular characterization of HLA genes in the IHWG reference B-lymphoblastoid cell lines (B-LCLs) was one of the major goals for the 17th International HLA and Immunogenetics Workshop (IHIW). Although reference B-LCLs have been examined extensively in previous workshops complete high-resolution typing was not completed for all the classical class I and class II HLA genes. To address this, we conducted a single-blind study where select panels of B-LCL genomic DNA samples were distributed to multiple laboratories for HLA genotyping by next-generation sequencing methods. Identical cell panels comprised of 24 and 346 samples were distributed and typed by at least four laboratories in order to derive accurate consensus HLA genotypes. Overall concordance rates calculated at both 2- and 4-field allele-level resolutions ranged from 90.4% to 100%. Concordance for the class I genes ranged from 91.7 to 100%, whereas concordance for class II genes was variable; the lowest observed at HLA-DRB3 (84.2%). At the maximum allele-resolution 78 B-LCLs were defined as homozygous for all 11 loci. We identified 11 novel exon polymorphisms in the entire cell panel. A comparison of the B-LCLs NGS HLA genotypes with the HLA genotypes catalogued in the IPD-IMGT/HLA Database Cell Repository, revealed an overall allele match at 68.4%. Typing discrepancies between the two datasets were mostly due to the lower-resolution historical typing methods resulting in incomplete HLA genotypes for some samples listed in the IPD-IMGT/HLA Database Cell Repository. Our approach of multiple-laboratory NGS HLA typing of the B-LCLs has provided accurate genotyping data. The data generated by the tremendous collaborative efforts of the 17th IHIW participants is useful for updating the current cell and sequence databases and will be a valuable resource for future studies.

TFEB-mediated Enhancement of the Autophagy-lysosomal Pathway Dually Modulates the Process of Amyloid β-Protein Generation in Neurons

Abnormalities of the autophagy-lysosomal pathway (ALP) have been implicated in the pathology of Alzheimer's disease (AD). Activation of TFEB (transcription factor EB), a master regulator of the ALP, leads to ALP facilitation. The present study sought to clarify whether TFEB-mediated ALP facilitation influences the process of amyloid β-protein (Aβ) generation in neurons. TFEB was overexpressed in mature rat primary cortical neurons via recombinant adenoviruses, without (basal conditions) or with co-overexpression of wild-type amyloid precursor protein (APP) or its β-C-terminal fragment (β-CTF). We confirmed that TFEB overexpression upregulated the lysosomal proteins, cathepsin D and LAMP-1. In TFEB-expressing neurons, protein levels of ADAM10 were profoundly increased, whereas those of APP, BACE1, or γ-secretase complex proteins were unaffected. However, TFEB did not affect ADAM10 mRNA levels. TFEB overexpression had different effects on Aβ production depending on the expression level of APP or β-CTF: TFEB slightly decreased Aβ secretion under basal conditions; clearly increased α-CTF levels and marginally increased β-CTF levels with modest increases in secreted Aβ in APP-expressing neurons; and caused a remarkable increase in β-CTF levels with a significant increase in secreted Aβ in β-CTF-expressing neurons. Inhibition of proteasomes, but not lysosomes, markedly increased β-CTF levels in β-CTF-expressing neurons. These results collectively indicate that TFEB modulates Aβ production not only by increasing α-secretase processing of APP through ADAM10 upregulation but also by augmenting β-CTF levels possibly via altered proteasome-mediated catabolism. Thus, TFEB-mediated ALP enhancement appears to have dual, but opposite, effects on Aβ production in neurons.

The neurotoxicity of amyloid β-protein oligomers is reversible in a primary neuron model

Alzheimer’s disease (AD) is characterized by the accumulation of extracellular amyloid β-protein (Aβ) and intracellular hyperphosphorylated tau proteins. Recent evidence suggests that soluble Aβ oligomers elicit neurotoxicity and synaptotoxicity, including tau abnormalities, and play an initiating role in the development of AD pathology. In this study, we focused on the unclarified issue of whether the neurotoxicity of Aβ oligomers is a reversible process. Using a primary neuron culture model, we examined whether the neurotoxic effects induced by 2-day treatment with Aβ42 oligomers (Aβ-O) are reversible during a subsequent 2-day withdrawal period. Aβ-O treatment resulted in activation of caspase-3 and eIF2α, effects that were considerably attenuated following Aβ-O removal. Immunocytochemical analyses revealed that Aβ-O induced aberrant phosphorylation and caspase-mediated cleavage of tau, both of which were mostly reversed by Aβ-O removal. Furthermore, Aβ-O caused intraneuronal dislocation of β-catenin protein and a reduction in its levels, and these alterations were partially reversed upon Aβ-O withdrawal. The dislocation of β-catenin appeared to reflect synaptic disorganization. These findings indicate that removal of extracellular Aβ-O can fully or partially reverse Aβ-O-induced neurotoxic alterations in our neuron model. Accordingly, we propose that the induction of neurotoxicity by Aβ oligomers is a reversible process, which has important implications for the development of AD therapies.

Assessment of in vitro antiovulatory activities of nonsteroidal anti-inflammatory drugs and comparison with in vivo reproductive toxicities of medaka (Oryzias latipes)

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used therapeutic agents; however, their pharmacological actions raise concerns about potential risks to the reproductive health of aquatic vertebrates. In the present study, a medaka ovulation assay was applied as an in vitro model to evaluate NSAID-induced antiovulatory activity. We first tested five NSAIDs, including diclofenac sodium (DCF), ketoprofen (KP), salicylic acid (SA), mefenamic acid (MA), and acetylsalicylic acid (ASA) for their antiovulatory activities toward the follicles isolated from the ovaries of spawning females. Of all the chemicals tested, DCF had the highest antiovulatory activity, with the concentration that caused 50% inhibition (IC50) (101 µM). MA was the second most potent inhibitor following DCF, but KP, SA, or ASA had little inhibitory effect on the ovulation of the follicles. The in vitro antiovulatory activity of five NSAIDs showed good correlation with data published on the inhibitory activity on human COX-2. Second, we selected DCF and SA as the most and least potent NSAIDs, respectively, and examined the effects on reproduction of intact fish in order to evaluate whether the ovulation assay was a reasonable predictor of potential reproductive effects in fish. Females exposed to DCF showed a concentration-dependent decrease in the number of spawned eggs and an increment in the gonadosomatic index (GSI), possibly due to an anovulation in the females. In contrast, neither fecundity nor the GSI of females decreased at up to 20 mg/L of SA, at which acute lethality to medaka was induced. In conclusion, the medaka ovulation assay reflected the potency of NSAID-induced antiovulatory activity and may thus serve as an in vitro model for the prediction of NSAID-induced reproductive toxicity. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1710-1719, 2016.

Vestibular Impairment in Frontotemporal Dementia Syndrome

Background

No studies to date have attempted to evaluate frontotemporal lobar degeneration from the perspective of the vestibular system.

Objective

The present study examined vestibular function in patients with frontotemporal dementia (FTD) clinical syndrome and evaluated whether vestibular disorders are involved in the clinical symptoms due to FTD.

Methods

Fourteen patients with FTD syndrome, as well as healthy elderly controls without dementia, were included in the present study. All subjects underwent vestibular function tests using electronystagmography, such as caloric tests and visual suppression (VS) tests, in which the induced caloric nystagmus was suppressed by visual stimuli. The association between clinical symptoms and vestibular function in the FTD syndrome group was further examined.

Results

In the FTD syndrome group, caloric nystagmus was not necessarily suppressed during VS tests. Furthermore, VS was observed to be significantly impaired in FTD syndrome patients with gait disturbance as compared to those without such disturbance.

Conclusion

The present study revealed that impairment of VS in patients with FTD results in an inability to regulate vestibular function by means of visual perception, regardless of multiple presumed neuropathological backgrounds. This could also be associated with gait disturbance in patients with FTD syndrome.