Faculty Bibliography

Misfolding and aggregation of disease-specific proteins, resulting in the formation of filamentous cellular inclusions, is a hallmark of neurodegenerative disease with characteristic filament structures, or conformers, defining each proteinopathy. Here we show that a previously unsolved amyloid fibril composed of a 135 amino acid C-terminal fragment of TMEM106B is a common finding in distinct human neurodegenerative diseases, including cases characterized by abnormal aggregation of TDP-43, tau, or α-synuclein protein. A combination of cryoelectron microscopy and mass spectrometry was used to solve the structures of TMEM106B fibrils at a resolution of 2.7 Å from postmortem human brain tissue afflicted with frontotemporal lobar degeneration with TDP-43 pathology (FTLD-TDP, n = 8), progressive supranuclear palsy (PSP, n = 2), or dementia with Lewy bodies (DLB, n = 1). The commonality of abundant amyloid fibrils composed of TMEM106B, a lysosomal/endosomal protein, to a broad range of debilitating human disorders indicates a shared fibrillization pathway that may initiate or accelerate neurodegeneration.

BACKGROUND/UNASSIGNED:Treatment for head and neck cancer (HNC) such as radiotherapy (RT) can lead to numerous acute and chronic head and neck sequelae, including dental caries. The goal of the present study was to measure 2-y changes in dental caries after radiotherapy in patients with HNC and test risk factors for caries increment. METHODS/UNASSIGNED:Cancer and dental disease characteristics, demographics, and oral health practices were documented before and 6, 12, 18, and 24 mo after the start of RT for 572 adult patients with HNC. Patients were eligible if they were age 18 y or older, diagnosed with HNC, and planned to receive RT for treatment of HNC. Caries prevalence was measured as decayed, missing, and filled surfaces (DMFS). The association between change in DMFS and risk factors was evaluated using linear mixed models. RESULTS/UNASSIGNED:= 164), lower salivary flow at follow-up visits was associated with increased DMFS. CONCLUSION/UNASSIGNED:Increased caries is a complication soon after RT in HNC. Fluoride, oral hygiene, dental insurance, and education level had the strongest association with caries increment after radiotherapy to the head and neck region. Thus, intensive oral hygiene measures, including fluoride and greater accessibility of dental care, may contribute to reducing the caries burden after RT in HNC. KNOWLEDGE TRANSFER STATEMENT/UNASSIGNED:The results of this study can be used by clinicians when deciding how to minimize oral complications related to cancer therapy for patients with head and neck cancer. Identification of modifiable factors (e.g., oral hygiene and prescription fluoride compliance) associated with increased caries risk can minimize radiation caries burden.

BACKGROUND:The characteristics of community members exposed to World Trade Center (WTC) dust and fumes with Chronic Obstructive Pulmonary Disease (COPD) can provide insight into mechanisms of airflow obstruction in response to an environmental insult, with potential implications for interventions. METHODS:We performed a baseline assessment of respiratory symptoms, spirometry, small airway lung function measures using respiratory impulse oscillometry (IOS), and blood biomarkers. COPD was defined by the 2019 GOLD criteria for COPD. Patients in the WTC Environmental Health Center with <5 or ≥5 pack year smoking history were classified as nonsmoker-COPD (ns-COPD) or smoker-COPD (sm-COPD), respectively. MAIN RESULTS/RESULTS:= 0.007). CONCLUSIONS:Spirometry findings and small airway measures, as well as inflammatory markers, differed between patients with ns-COPD and sm-COPD. These findings suggest potential for differing mechanisms of airway injury in patients with WTC environmental exposures and have potential therapeutic implications.

Bimanual movements that require coordinated actions of the two hands may be coordinated by synchronous bilateral activation of somatosensory and motor cortical areas in both hemispheres, by enhanced activation of individual neurons specialized for bimanual actions, or by both mechanisms. To investigate cortical neural mechanisms that mediate unimanual and bimanual prehension, we compared actions of the left and right hands in a reach to grasp-and-pull instructed-delay task. Spike trains were recorded with multiple electrode arrays placed in the hand area of primary motor (M1) and somatosensory (S1) cortex of the right hemisphere in macaques, allowing us to measure and compare the relative timing, amplitude, and synchronization of cortical activity in these areas as animals grasped and manipulated objects that differed in shape and location. We report that neurons in the right hemisphere show common task-related firing patterns for the two hands but actions of the ipsilateral hand elicited weaker and shorter-duration responses than those of the contralateral hand. We report significant bimanual activation of neurons in M1 but not in S1 cortex when animals have free choice of hand use in prehension tasks. Population ensemble responses in M1 thereby provide an accurate depiction of hand actions during skilled manual tasks. These studies also demonstrate that somatosensory cortical areas serve important cognitive and motor functions in skilled hand actions. Bilateral representation of hand actions may serve an important role in "motor equivalence" when the same movements are performed by either hand and in transfer of skill learning between the hands.NEW & NOTEWORTHY Humans can manipulate small objects with the right or left hand but typically select the dominant hand to handle them. We trained monkeys to grasp and manipulate objects with either hand, while recording neural activity in primary motor (M1) and somatosensory (S1) cortex. Actions of both hands activate M1 neurons, but S1 neurons respond only to the contralateral hand. Bilateral sensitivity in M1 may aid skill transfer between hands after stroke or head injury.

The engineering of patient T-cells for adoptive cell therapies has revolutionized the treatment of several cancer types. However, further improvements are needed to increase durability and response rate. While CRISPR-based loss-of-function screens have shown promise for high-throughput identification of genes that modulate T-cell response, these methods have been limited thus far to negative regulators of T-cell functions, and raise safety concerns due to the permanent nature of genome modification. Here we identify positive T-cell regulators via overexpression of ~12,000 barcoded human open reading frames (ORFs). Using this genome-scale ORF screen, we find modulator genes that may not normally be expressed by T-cells. The top-ranked genes increased primary human T-cell proliferation, activation, and secretion of key cytokines. In addition, we developed a single-cell genomics method for high-throughput quantification of the transcriptome and surface proteome in ORF-engineered T-cells. The top-ranked ORF, lymphotoxin beta receptor (LTBR), is typically expressed by myeloid cells but absent in lymphocytes. When expressed in T-cells, LTBR induced profound transcriptional and epigenomic remodeling, resulting in an increase in T-cell stemness and effector functions, as well as resistance to apoptosis and exhaustion in chronic stimulation settings. Using mutagenesis and epistasis approaches, we demonstrated that LTBR constitutive activates the canonical NFkB pathway via ligand shortcircuiting and tonic signaling. Expression of several top-ranked genes, including LTBR, improved antigen-specific chimeric antigen receptor (CAR) T-cell responses in healthy donors and diffuse large B-cell lymphoma patients. Finally, the top-ranked genes discovered in alphabeta T-cells also improved antigen-specific responses of gammadelta T-cells, highlighting the potential for cancer-agnostic therapies. Our results provide several strategies for improving next generation T-cell therapies via induction of new synthetic cell programs

Methotrexate is used in the treatment of many malignancies, rheumatological diseases, and inflammatory bowel disease. Toxicity from use is associated with severe morbidity and mortality. Rescue treatments include intravenous hydration, folinic acid, and, in some centers, glucarpidase. We conducted systematic reviews of the literature following published EXtracorporeal TReatments In Poisoning (EXTRIP) methods to determine the utility of extracorporeal treatments in the management of methotrexate toxicity. The quality of the evidence and the strength of recommendations (either "strong" or "weak/conditional") were graded according to the GRADE approach. A formal voting process using a modified Delphi method assessed the level of agreement between panelists on the final recommendations. A total of 92 articles met inclusion criteria. Toxicokinetic data were available on 90 patients (89 with impaired kidney function). Methotrexate was considered to be moderately dialyzable by intermittent hemodialysis. Data were available for clinical analysis on 109 patients (high-dose methotrexate [>0.5 g/m²]: 91 patients; low-dose [≤0.5 g/m²]: 18). Overall mortality in these publications was 19.5% and 26.7% in those with high-dose and low-dose methotrexate-related toxicity, respectively. Although one observational study reported lower mortality in patients treated with glucarpidase compared with those treated with hemodialysis, there were important limitations in the study. For patients with severe methotrexate toxicity receiving standard care, the EXTRIP workgroup: (1) suggested against extracorporeal treatments when glucarpidase is not administered; (2) recommended against extracorporeal treatments when glucarpidase is administered; and (3) recommended against extracorporeal treatments instead of administering glucarpidase. The quality of evidence for these recommendations was very low. Rationales for these recommendations included: (1) extracorporeal treatments mainly remove drugs in the intravascular compartment, whereas methotrexate rapidly distributes into cells; (2) extracorporeal treatments remove folinic acid; (3) in rare cases where fast removal of methotrexate is required, glucarpidase will outperform any extracorporeal treatment; and (4) extracorporeal treatments do not appear to reduce the incidence and magnitude of methotrexate toxicity.

The increasingly appreciated prevalence of complicated stressor-to-phenotype associations in human disease requires a greater understanding of how specific stressors affect systems or interactome properties. Many currently untreatable diseases arise due to variations in, and through a combination of, multiple stressors of genetic, epigenetic, and environmental nature. Unfortunately, how such stressors lead to a specific disease phenotype or inflict a vulnerability to some cells and tissues but not others remains largely unknown and unsatisfactorily addressed. Analysis of cell- and tissue-specific interactome networks may shed light on organization of biological systems and subsequently to disease vulnerabilities. However, deriving human interactomes across different cell and disease contexts remains a challenge. To this end, this opinion article links stressor-induced protein interactome network perturbations to the formation of pathologic scaffolds termed epichaperomes, revealing a viable and reproducible experimental solution to obtaining rigorous context-dependent interactomes. This article presents our views on how a specialized 'omics platform called epichaperomics may complement and enhance the currently available conventional approaches and aid the scientific community in defining, understanding, and ultimately controlling interactome networks of complex diseases such as Alzheimer's disease. Ultimately, this approach may aid the transition from a limited single-alteration perspective in disease to a comprehensive network-based mindset, which we posit will result in precision medicine paradigms for disease diagnosis and treatment.

PURPOSE/OBJECTIVE:The paper introduces a classical model to describe the dynamics of large spin-1/2 ensembles associated with nuclei bound in large molecule structures, commonly referred to as the semi-solid spin pool, and their magnetization transfer (MT) to spins of nuclei in water. THEORY AND METHODS/UNASSIGNED:Like quantum-mechanical descriptions of spin dynamics and like the original Bloch equations, but unlike existing MT models, the proposed model is based on the algebra of angular momentum in the sense that it explicitly models the rotations induced by radiofrequency (RF) pulses. It generalizes the original Bloch model to non-exponential decays, which are, for example, observed for semi-solid spin pools. The combination of rotations with non-exponential decays is facilitated by describing the latter as Green's functions, comprised in an integro-differential equation. RESULTS:Our model describes the data of an inversion-recovery magnetization-transfer experiment with varying durations of the inversion pulse substantially better than established models. We made this observation for all measured data, but in particular for pulse durations smaller than 300 μs. Furthermore, we provide a linear approximation of the generalized Bloch model that reduces the simulation time by approximately a factor 15,000, enabling simulation of the spin dynamics caused by a rectangular RF-pulse in roughly 2 μs. CONCLUSION/CONCLUSIONS:The proposed theory unifies the original Bloch model, Henkelman's steady-state theory for MT, and the commonly assumed rotation induced by hard pulses (i.e., strong and infinitesimally short applications of RF-fields) and describes experimental data better than previous models.

OBJECTIVE:The effectiveness of µ-opioid receptor (MOPr) agonists for treatment of visceral pain is compromised by constipation, respiratory depression, sedation and addiction. We investigated whether a fentanyl analogue, (±)-N-(3-fluoro-1-phenethylpiperidine-4-yl)-N-phenyl propionamide (NFEPP), which preferentially activates MOPr in acidified diseased tissues, would inhibit pain in a preclinical model of inflammatory bowel disease (IBD) without side effects in healthy tissues. DESIGN/METHODS:Antinociceptive actions of NFEPP and fentanyl were compared in control mice and mice with dextran sodium sulfate colitis by measuring visceromotor responses to colorectal distension. Patch clamp and extracellular recordings were used to assess nociceptor activation. Defecation, respiration and locomotion were assessed. Colonic migrating motor complexes were assessed by spatiotemporal mapping of isolated tissue. NFEPP-induced MOPr signalling and trafficking were studied in human embryonic kidney 293 cells. RESULTS:NFEPP inhibited visceromotor responses to colorectal distension in mice with colitis but not in control mice, consistent with acidification of the inflamed colon. Fentanyl inhibited responses in both groups. NFEPP inhibited the excitability of dorsal root ganglion neurons and suppressed mechanical sensitivity of colonic afferent fibres in acidified but not physiological conditions. Whereas fentanyl decreased defecation and caused respiratory depression and hyperactivity in mice with colitis, NFEPP was devoid of these effects. NFEPP did not affect colonic migrating motor complexes at physiological pH. NFEPP preferentially activated MOPr in acidified extracellular conditions to inhibit cAMP formation, recruit β-arrestins and evoke MOPr endocytosis. CONCLUSION/CONCLUSIONS:In a preclinical IBD model, NFEPP preferentially activates MOPr in acidified microenvironments of inflamed tissues to induce antinociception without causing respiratory depression, constipation and hyperactivity.

Recently, "Technical standards for respiratory oscillometry" was published, which reviewed the physiological basis of oscillometric measures and detailed the technical factors related to equipment and test performance, quality assurance and reporting of results. Here we present a review of the clinical significance and applications of oscillometry. We briefly review the physiological principles of oscillometry and the basics of oscillometry interpretation, and then describe what is currently known about oscillometry in its role as a sensitive measure of airway resistance, bronchodilator responsiveness and bronchial challenge testing, and response to medical therapy, particularly in asthma and COPD. The technique may have unique advantages in situations where spirometry and other lung function tests are not suitable, such as in infants, neuromuscular disease, sleep apnoea and critical care. Other potential applications include detection of bronchiolitis obliterans, vocal cord dysfunction and the effects of environmental exposures. However, despite great promise as a useful clinical tool, we identify a number of areas in which more evidence of clinical utility is needed before oscillometry becomes routinely used for diagnosing or monitoring respiratory disease.