Adaptive immune protection of the middle ears differs from that of the respiratory tract

The efficacy of the adaptive immune system in the middle ear (ME) is well established, but the mechanisms are not as well defined as those of gastrointestinal or respiratory tracts. While cellular elements of the adaptive response have been detected in the MEs following infections (or intranasal immunizations), their specific contributions to protecting the organ against reinfections are unknown. How immune protection mechanisms of the MEs compares with those in the adjacent and attached upper and lower respiratory airways remains unclear. To address these knowledge gaps, we used an established mouse respiratory infection model that we recently showed also involves ME infections. Bordetella bronchiseptica delivered to the external nares of mice in tiny numbers very efficiently infects the respiratory tract and ascends the Eustachian tube to colonize and infect the MEs, where it causes severe but acute inflammation resembling human acute otitis media (AOM). Since this AOM naturally resolves, we here examine the immunological mechanisms that clear infection and protect against subsequent infection, to guide efforts to induce protective immunity in the ME. Our results show that once the MEs are cleared of a primary B. bronchiseptica infection, the convalescent organ is strongly protected from reinfection by the pathogen despite its persistence in the upper respiratory tract, suggesting important immunological differences in these adjacent and connected organs. CD4+ and CD8+ T cells trafficked to the MEs following infection and were necessary to robustly protect against secondary challenge. Intranasal vaccination with heat killed B. bronchiseptica conferred robust protection against infection to the MEs, even though the nasopharynx itself was only partially protected. These data establish the MEs as discrete effector sites of adaptive immunity and shows that effective protection in the MEs and the respiratory tract is significantly different. This model system allows the dissection of immunological mechanisms that can prevent bacteria in the nasopharynx from ascending the ET to colonize the ME

The Team-Mate Identification (TM-ID) Test: Effect of Participant and Situation Familiarity on Response Accuracy and Latency

In field and pool sports, players' running or swimming motor patterns appear to characterise them, and these ‘gait signatures’ may aid in identifying players as team-mates. If this identification process was sufficiently brief to be relevant in ball sports, training to improve familiarity with team-mates' movement patterns may improve team performance. We examined time for Team-Mate Identification (TM-ID) decisions under different circumstances. 6 water-polo players (team-mate participants) and 6 club swimmers (unknown distractors) were filmed sprint swimming past two video cameras, one above and one below the water surface. The resulting footage was edited into two randomised series of video-clips. The water-polo players then viewed the clips and determined whether each observed swimmer was a team-mate or not, in the fastest possible time. Participants were faster with an overwater than an underwater view, significantly better than chance at identifying their team-mates, and did so in a mean time of 381 ms, which is within the normal window of time where expert sports people might be required to make time-stressed decisions

Variant-dependent heterogeneity in amyloid β burden in autosomal dominant Alzheimer's disease: cross-sectional and longitudinal analyses of an observational study

Background Insights gained from studying individuals with autosomal dominant Alzheimer’s disease have broadly influenced mechanistic hypotheses, biomarker development, and clinical trials in both sporadic and dominantly inherited Alzheimer’s disease. Although pathogenic variants causing autosomal dominant Alzheimer’s disease are highly penetrant, there is substantial heterogeneity in levels of amyloid β (Aβ) between individuals. We aimed to examine whether this heterogeneity is related to disease progression and to investigate the association with mutation location within PSEN1, PSEN2, or APP. Methods We did cross-sectional and longitudinal analyses of data from the Dominantly Inherited Alzheimer’s Network (DIAN) observational study, which enrols individuals from families affected by autosomal dominant Alzheimer’s disease. 340 participants in the DIAN study who were aged 18 years or older, had a history of autosomal dominant Alzheimer’s disease in their family, and who were enrolled between September, 2008, and June, 2019, were included in our analysis. 206 participants were carriers of pathogenic mutations in PSEN1, PSEN2, or APP, and 134 were non-carriers. 62 unique pathogenic variants were identified in the cohort and were grouped in two ways. First, we sorted variants in PSEN1, PSEN2, or APP by the affected protein domain. Second, we divided PSEN1 variants according to position before or after codon 200. We examined variant-dependent variability in Aβ biomarkers, specifically Pittsburgh-Compound-B PET (PiB-PET) signal, levels of CSF Aβ1-42 (Aβ42), and levels of Aβ1-40 (Aβ40). Findings Cortical and striatal PiB-PET signal showed striking variant-dependent variability using both grouping approaches (p0·7), and CSF Aβ42 levels (codon-based grouping: p=0·49; domain-based grouping: p=0·095). Longitudinal PiB-PET signal also varied across codon-based groups, mirroring cross-sectional analyses. Interpretation Autosomal dominant Alzheimer’s disease pathogenic variants showed highly differential temporal and regional patterns of PiB-PET signal, despite similar functional progression. These findings suggest that although increased PiB-PET signal is generally seen in autosomal dominant Alzheimer’s disease, higher levels of PiB-PET signal at an individual level might not reflect more severe or more advanced disease. Our results have high relevance for ongoing clinical trials in autosomal dominant Alzheimer’s disease, including those using Aβ PET as a surrogate marker of disease progression. Additionally, and pertinent to both sporadic and autosomal dominant Alzheimer’s disease, our results suggest that CSF and PET measures of Aβ levels are not interchangeable and might reflect different Aβ-driven pathobiological processes

A soluble phosphorylated tau signature links tau, amyloid and the evolution of stages of dominantly inherited Alzheimer's disease

Site-specific hyperphosphorylations of tau in the cerebrospinal fluid change with disease course, and correlate with pathology and cognitive decline in dominantly inherited Alzheimer's disease. Development of tau-based therapies for Alzheimer's disease requires an understanding of the timing of disease-related changes in tau. We quantified the phosphorylation state at multiple sites of the tau protein in cerebrospinal fluid markers across four decades of disease progression in dominantly inherited Alzheimer's disease. We identified a pattern of tau staging where site-specific phosphorylation changes occur at different periods of disease progression and follow distinct trajectories over time. These tau phosphorylation state changes are uniquely associated with structural, metabolic, neurodegenerative and clinical markers of disease, and some (p-tau217 and p-tau181) begin with the initial increases in aggregate amyloid-beta as early as two decades before the development of aggregated tau pathology. Others (p-tau205 and t-tau) increase with atrophy and hypometabolism closer to symptom onset. These findings provide insights into the pathways linking tau, amyloid-beta and neurodegeneration, and may facilitate clinical trials of tau-based treatments

Clinical impact of COVID-19 on patients with cancer (CCC19): a cohort study

BACKGROUND: Data on patients with COVID-19 who have cancer are lacking. Here we characterise the outcomes of a cohort of patients with cancer and COVID-19 and identify potential prognostic factors for mortality and severe illness. METHODS: In this cohort study, we collected de-identified data on patients with active or previous malignancy, aged 18 years and older, with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection from the USA, Canada, and Spain from the COVID-19 and Cancer Consortium (CCC19) database for whom baseline data were added between March 17 and April 16, 2020. We collected data on baseline clinical conditions, medications, cancer diagnosis and treatment, and COVID-19 disease course. The primary endpoint was all-cause mortality within 30 days of diagnosis of COVID-19. We assessed the association between the outcome and potential prognostic variables using logistic regression analyses, partially adjusted for age, sex, smoking status, and obesity. This study is registered with ClinicalTrials.gov, NCT04354701, and is ongoing. FINDINGS: Of 1035 records entered into the CCC19 database during the study period, 928 patients met inclusion criteria for our analysis. Median age was 66 years (IQR 57-76), 279 (30%) were aged 75 years or older, and 468 (50%) patients were male. The most prevalent malignancies were breast (191 [21%]) and prostate (152 [16%]). 366 (39%) patients were on active anticancer treatment, and 396 (43%) had active (measurable) cancer. At analysis (May 7, 2020), 121 (13%) patients had died. In logistic regression analysis, independent factors associated with increased 30-day mortality, after partial adjustment, were: increased age (per 10 years; partially adjusted odds ratio 1·84, 95% CI 1·53-2·21), male sex (1·63, 1·07-2·48), smoking status (former smoker vs never smoked: 1·60, 1·03-2·47), number of comorbidities (two vs none: 4·50, 1·33-15·28), Eastern Cooperative Oncology Group performance status of 2 or higher (status of 2 vs 0 or 1: 3·89, 2·11-7·18), active cancer (progressing vs remission: 5·20, 2·77-9·77), and receipt of azithromycin plus hydroxychloroquine (vs treatment with neither: 2·93, 1·79-4·79; confounding by indication cannot be excluded). Compared with residence in the US-Northeast, residence in Canada (0·24, 0·07-0·84) or the US-Midwest (0·50, 0·28-0·90) were associated with decreased 30-day all-cause mortality. Race and ethnicity, obesity status, cancer type, type of anticancer therapy, and recent surgery were not associated with mortality. INTERPRETATION: Among patients with cancer and COVID-19, 30-day all-cause mortality was high and associated with general risk factors and risk factors unique to patients with cancer. Longer follow-up is needed to better understand the effect of COVID-19 on outcomes in patients with cancer, including the ability to continue specific cancer treatments. FUNDING: American Cancer Society, National Institutes of Health, and Hope Foundation for Cancer Research