Citations

Human immune system (HIS) mice constructed in various ways are widely used for investigations of human immune responses to pathogens, transplants, and immunotherapies. In HIS mice that generate T cells de novo from hematopoietic progenitors, T cell-dependent multisystem autoimmune disease occurs, most rapidly when the human T cells develop in the native NOD.Cg- Prkdc scid Il2rg tm1Wjl (NSG) mouse thymus, where negative selection is abnormal. Disease develops very late when human T cells develop in human fetal thymus grafts, where robust negative selection is observed. We demonstrate here that PD-1 + CD4 + peripheral (Tph) helper-like and follicular (Tfh) helper-like T cells developing in HIS mice can induce autoimmune disease. Tfh-like cells were more prominent in HIS mice with a mouse thymus, in which the highest levels of IgG were detected in plasma, compared to those with a human thymus. While circulating IgG and IgM antibodies were autoreactive to multiple mouse antigens, in vivo depletion of B cells and antibodies did not delay the development of autoimmune disease. Conversely, adoptive transfer of enriched Tfh- or Tph-like cells induced disease and autoimmunity-associated B cell phenotypes in recipient mice containing autologous human APCs without T cells. Tfh/Tph cells from mice with a human thymus expanded and induced disease more rapidly than those originating in a murine thymus, implicating HLA-restricted T cell-APC interactions in this process. Since Tfh, Tph, autoantibodies, and lymphopenia-induced proliferation (LIP) have all been implicated in various forms of human autoimmune disease, the observations here provide a platform for the further dissection of human autoimmune disease mechanisms and therapies.

ABSTRACT Nosocomial outbreaks impact patient safety and place an economic burden on healthcare facilities. Laboratory testing plays a crucial role in outbreak investigation and guides containment efforts. In recent years, whole genome sequencing (WGS) methods have replaced traditional typing methods due to higher resolution and simplified workflows. Though an improvement from previous methods, bacterial WGS is time-consuming with manual DNA extraction and library preparation and long sequencing times for paired-end sequence data. Here, a fully automated library preparation and sequencing solution, the Clear Dx TM WGS platform (Clear Labs, San Carlos, CA), was compared to a more manual library preparation and sequencing approach using 226 isolates representing 18 bacterial species. Sequence data were analyzed using SeqSphere+ (Ridom, Münster, Germany), and the results of the two methods were compared. Of the 224 isolate sequences analyzed, 222 (99%) showed concordant isolate groupings, and, overall, the results of the two approaches were statistically similar by comparison of distance matrices. The automated workflow reduced turnaround time by 16–19 h and eliminated 3 h of manual labor while decreasing costs by an estimated 34%–57% depending on the number of isolates run. This study demonstrates the advantages of integrating automation into bacterial WGS workflows. IMPORTANCE An automated platform for bacterial nucleic acid extraction and whole genome sequencing was compared to a manual method for bacterial strain typing. The two approaches yielded nearly equivalent results, with the automated approach providing improvement in turnaround time and cost, with less manual pipetting.

Purpose: This study examined if vertical bladder excursion during pelvic floor muscle (PFM) contraction, measured with transabdominal ultrasound (TAUS), improved following a single training session 0-5 days postpartum. It also assessed patient satisfaction with the training. Methods: 75 healthy, female volunteers within 0-5 days post-vaginal delivery were recruited during their inpatient postpartum stay. Participants completed one in-person session involving a standardized bladder filling protocol, TAUS imaging during PFM contractions, a PFM training session using TAUS as visual biofeedback, and a two-question post intervention survey. Vertical bladder base excursions were compared pre- and post- training between two groups: those whose bladder bases descended and those whose ascended during baseline contractions. A mixed model ANOVA with one between-group factor (baseline descenders vs. ascenders) and one within-group factor (pre- vs. post-training) analyzed the change in bladder lift. Patient satisfaction was assessed with Likert scales. Results: Mean vertical excursion increased from 0.12 cm (SD = 0.48) to 0.32 cm (SD = 0.33) post-training, which was statistically significant (p <.001, Cohens d = 0.767). Greater improvements were noted in those with a bladder base descent at baseline. All participants reported the experience to be helpful or very helpful and were satisfied or very satisfied. Discussion: Participants increased vertical bladder excursion during PFM contraction with TAUS biofeedback within a single session, especially those with baseline paradoxical bladder excursion and perineal trauma during delivery. Participants found the experience helpful and satisfying, suggesting TAUS biofeedback may be a useful tool in early postpartum PFM rehabilitation.

Background: Despite the availability of effective vaccines and a recent decrease in annual deaths, coronavirus disease-2019 (COVID-19) remains a leading cause of death. Serological studies of anti-nucleocapsid (N) antibody response to infection provide insights into host immunobiology of adaptive immune response, which holds promise for identifying high-risk individuals for adverse acute and chronic COVID-19 outcomes. Hypothesis: Among participants previously infected with SARS-CoV-2, traditional vascular disease risk factors are associated with higher anti-N antibodies while vaccination is associated with lower anti-N antibodies. Methods: Among previously infected participants, anti-N antibodies were measured from dried blood spots collected between February 2021-February 2023 among 1,419 Collaborative Cohort of Cohorts for COVID-19 Research (C4R) participants with prior SARS-CoV-2 infection. We measured anti-N IgG antibodies reported as median fluorescence intensity (MFI) units; reactivity (i.e., seropositivity) was defined based on MFI above a validated threshold. Vascular disease risk factors were assessed via pre-pandemic in-person examination, questionnaires, and medical record review. Multivariable generalized linear models regressed anti-N reactivity (modified Poisson) or LN transformed MFI (linear). Results: Among 1,419 participants with prior infection, mean age (standard deviation) was 65.8(12.1) years, 61% were women, and 42.8% were self-reported from a race/ethnicity minority group. Participant reactivity to nucleocapsid peaked at 69% by 4 months post-infection and waned to only 44% ≥12 months after infection. After multivariable adjustment, higher anti-N antibody response was associated with older age, Hispanic (vs. White) or American Indian (vs. White) race/ethnicity, lower income and education, former smoking, and higher anti-spike antibody levels. Asian race (vs. White) and vaccination ( even after infection ) were associated with lower nucleocapsid reactivity; common cardiometabolic co-morbidities were not associated with anti-N reactivity or levels (Figures 1 and 2). Conclusions: Among participants previously infected with SARS-CoV-2, select sociodemographic and behavioral risk factors were associated with higher anti-N antibody levels while vaccination was associated with lower anti-N antibody levels. The observation that vaccination, even after infection, is related to lower anti-N antibody levels merits further investigation.

Abstract Background The lupus anticoagulant (LAC) is an important laboratory criterion in the diagnosis of antiphospholipid antibody syndrome. LAC testing at the Mayo Clinic Special Coagulation Laboratory includes up to 13 tests, which are interpreted by trained physicians to identify the presence of LAC and rule out anticoagulant interferences. This feasibility study explored the use of two deep neural network (DNN) architectures for multilabel classification of LAC profiles as a first step toward automating interpretation. Methods Seven thousand two hundred and two retrospective cases were randomly split (64:16:20) for training, validation, and test, respectively. LAC positivity by dilute Russell's viper venom time (LAC-DRVVT) and activated partial thromboplastin time (LAC-APTT) and the presence of warfarin (WAR) and heparin (HEP) were adjudicated by one expert. DNN architectures included: single-output DNNs using domain-knowledge input feature selection and a single-column multioutput DNN using all 13 inputs. Results Domain-knowledge-naïve multioutput DNN achieved similar or improved performance for all 4 label prediction tasks compared with domain knowledge optimized DNNs: F1 scores of 0.977 vs 0.968 for LAC-DRVVT, 0.954 vs 0.945 for LAC-APTT, 0.961 vs 0.957 for HEP, and 0.995 vs 0.977 for WAR, respectively. Conclusions The comparable performance of the 4 domain knowledge optimized DNNs and the multioutput DNN using all 13 input features suggests that the DNN may learn feature importance or mapping to a task without explicit input selection. Given its relative simplicity and versatility, the multioutput DNN is the preferred choice for implementation in a clinical laboratory to standardize LAC diagnosis.

Pregnancy induces significant physiologic changes that impact the cardiovascular system, potentially exacerbating pre-existing cardiac conditions or precipitating new illnesses. Pregnant patients with cardiac emergencies pose unique challenges, as standard interventions may pose risks to the developing fetus. This article aims to enhance emergency physicians’ confidence in managing pregnancy-related cardiac emergencies by providing a structured approach to initial evaluation and stabilization. We review eight common categories of pregnancy-associated cardiac illness: gestational hypertension and pre-eclampsia, cardiomyopathy, arrhythmias, valvular disease, aortopathies, congenital heart disease and pulmonary hypertension, coronary disease, and anticoagulation-related complications. For each condition, we summarize relevant pregnancy-specific pathophysiology and outline evidence-based, personalized emergency management strategies.