PD-1 defines a distinct, functional, tissue-adapted state in Vδ1+ T cells with implications for cancer immunotherapy.

Checkpoint inhibition (CPI), particularly that targeting the inhibitory coreceptor programmed cell death protein 1 (PD-1), has transformed oncology. Although CPI can derepress cancer (neo)antigen-specific αß T cells that ordinarily show PD-1-dependent exhaustion, it can also be efficacious against cancers evading αß T cell recognition. In such settings, γδ T cells have been implicated, but the functional relevance of PD-1 expression by these cells is unclear. Here we demonstrate that intratumoral TRDV1 transcripts (encoding the TCRδ chain of Vδ1+ γδ T cells) predict anti-PD-1 CPI response in patients with melanoma, particularly those harboring below average neoantigens. Moreover, using a protocol yielding substantial numbers of tissue-derived Vδ1+ cells, we show that PD-1+Vδ1+ cells display a transcriptomic program similar to, but distinct from, the canonical exhaustion program of colocated PD-1+CD8+ αß T cells. In particular, PD-1+Vδ1+ cells retained effector responses to TCR signaling that were inhibitable by PD-1 engagement and derepressed by CPI.

Characterization of a Musculoskeletal Syndrome of Enthesitis and Arthritis in Patients With Atopic Dermatitis Treated With Dupilumab, an Interleukin-4/13 Inhibitor.

OBJECTIVE: To characterize the presentation and outcomes of patients with atopic dermatitis (AD) who developed musculoskeletal symptoms after treatment with dupilumab, a human IgG4 monoclonal antibody that blocks the functions of interleukin-4 (IL-4) and IL-13, key pathologic pathways in AD. METHODS: This article reports an observational cohort of patients receiving dupilumab who developed new-onset musculoskeletal symptoms after dupilumab therapy at our center. All patients had a comprehensive rheumatologic history and examination, with imaging by ultrasonography (US) or magnetic resonance imaging (MRI) in most patients. RESULTS: Between October 2018 and February 2021, we recorded 470 patients with AD commencing dupilumab treatment from routine clinical care records. Of 36 patients referred for rheumatologic assessment, we identified 26 patients (14 male, 12 female) with a musculoskeletal syndrome of inflammatory enthesitis, arthritis, and/or tenosynovitis. Clinical findings were confirmed by US and MRI. All patients had very good response to dupilumab treatment, and no specific predictors of musculoskeletal syndrome were noted. Symptoms were mild in 16 patients, moderate in 6 patients, and severe in 4 patients. Receipt of nonsteroidal antiinflammatory drugs or cyclooxygenase 2 inhibitors, reduction of dupilumab dose/frequency, and cessation of dupilumab therapy led to improvement, but moderate or severe symptoms persisted for many months. CONCLUSION: We report a new musculoskeletal syndrome of inflammatory enthesitis/arthritis/tenosynovitis in some patients receiving the IL-4 receptor antagonist dupilumab. This response to a cytokine-targeting therapy provides key insights into the pathogenesis of enthesitis.

The clinical relevance of dupilumab serum concentration in patients with atopic dermatitis: a two-center prospective cohort study.

BACKGROUND: Dupilumab is prescribed in one dosage across adult atopic dermatitis patients. Differences in drug exposure may explain variation in treatment response. OBJECTIVE: Investigating the clinical relevance of dupilumab serum concentration in atopic dermatitis in real-world practice. METHODS: In two centers (Netherlands, UK), adults treated with dupilumab for atopic dermatitis were evaluated for effectiveness and safety pretreatment and at 2, 12, 24, and 48 weeks; trough serum samples were analyzed for dupilumab concentration at corresponding time points. RESULTS: In 149 patients, median dupilumab levels during follow-up ranged from 57.4 to 72.4 µg/mL. Levels showed high inter-patient and low intra-patient variability. No correlation was found between levels and ΔEASI. At 2 weeks, levels of ≥64.1 µg/mL predict EASI ≤7 at 24 weeks (specificity:100%, sensitivity:60%; p = .022). At 12 weeks, ≤32.7 µg/mL predicts EASI >7 at 24 weeks (sensitivity:95%, specificity:26%; p = .011). Inverse correlations were found between baseline EASI and levels at 2, 12, and 24 weeks (r = -0.25 to 0.36; p ≤ .023). Low levels were particularly observed in patients with adverse events, treatment interval deviation, and discontinuation. CONCLUSION: At the on-label dosage, the measured range of dupilumab levels does not seem to yield differences in treatment effectiveness. However, disease activity does seem to influence dupilumab levels - higher baseline disease activity results in lower levels at follow-up.

Real-World Implementation and Outcomes of Adalimumab Therapeutic Drug Monitoring in Psoriasis: A National Specialized Center Experience.

Serum adalimumab concentration is a biomarker of treatment response but therapeutic drug monitoring (TDM) is yet to be implemented in routine psoriasis care. We incorporated adalimumab TDM in a national specialized psoriasis service and evaluated it using the RE-AIM (Reach, Effectiveness, Adoption, Implementation, and Maintenance) implementation science framework. We undertook pre-implementation planning (validating local assays) and implementation interventions targeted to patients (pragmatic sampling at routine reviews), clinicians (introduction of a TDM protocol), and healthcare systems (adalimumab TDM as a key performance indicator). Over 5 months, 170 of 229 (74%) individuals treated with adalimumab received TDM. Clinical improvement after TDM-guided dose escalation occurred in 13 of 15 (87%) nonresponders with serum drug concentrations <8.3 µg/ml (median PASI reduction of 3.2 [interquartile range = 2.2-8.2] after 23.4 weeks) and in all nonresponders who had TDM-guided switch in biologic due to supratherapeutic drug concentrations (>8.3 µg/ml; n = 2) or positive antidrug antibody (n = 2) (PASI reduction of 7.8 [interquartile range = 7.5-12.9] after 20.0 weeks). Proactive TDM led to dose reduction in five individuals with clear skin and subtherapeutic or supratherapeutic drug concentrations; four (80%) sustained clear skin after 50 weeks (range = 42-52). Adalimumab TDM based on pragmatic serum sampling is clinically viable and may lead to patient benefit. Context-specific implementation interventions and systematic implementation assessment may bridge the biomarker research-to-practice gap.

Comparison of real-world treatment outcomes of systemic immunomodulating therapy in atopic dermatitis patients with dark and light skin types.

Background: Few data exist on differences in treatment effectiveness and safety in atopic dermatitis patients of different skin types. Objective: To investigate treatment outcomes of dupilumab, methotrexate, and ciclosporin, and morphological phenotypes in atopic dermatitis patients, stratified by Fitzpatrick skin type. Methods: In an observational prospective cohort study, pooling data from the Dutch TREAT (TREatment of ATopic eczema) NL (treatregister.nl) and UK-Irish A-STAR (Atopic eczema Systemic TherApy Register; astar-register.org) registries, data on morphological phenotypes and treatment outcomes were investigated. Results: A total of 235 patients were included (light skin types [LST]: Fitzpatrick skin type 1-3, n = 156 [Ethnicity, White: 94.2%]; dark skin types [DST]: skin type 4-6, n = 68 [Black African/Afro-Caribbean: 25%, South-Asian: 26.5%, and Hispanics: 0%]). DST were younger (19.5 vs 29.0 years; P < .001), more often had follicular eczema (22.1% vs 2.6%; P < .001), higher baseline Eczema Area and Severity Index (EASI) scores (20.1 vs 14.9; P = .009), less allergic contact dermatitis (30.9% vs 47.4%; P = .03), and less previous phototherapy use (39.7% vs 59.0%; P = .008). When comparing DST and LST corrected for covariates including baseline EASI, DST showed greater mean EASI reduction between baseline and 6 months with only dupilumab (16.7 vs 9.7; adjusted P = .032). No differences were found for adverse events for any treatments (P > .05). Limitations: Unblinded, non-randomized. Conclusion: Atopic dermatitis differs in several characteristics between LST and DST. Skin type may influence treatment effectiveness of dupilumab.

An innate-like Vδ1+ γδ T cell compartment in the human breast is associated with remission in triple-negative breast cancer.

Innate-like tissue-resident γδ T cell compartments capable of protecting against carcinogenesis are well established in mice. Conversely, the degree to which they exist in humans, their potential properties, and their contributions to host benefit are mostly unresolved. Here, we demonstrate that healthy human breast harbors a distinct γδ T cell compartment, primarily expressing T cell receptor (TCR) Vδ1 chains, by comparison to Vδ2 chains that predominate in peripheral blood. Breast-resident Vδ1+ cells were functionally skewed toward cytolysis and IFN-γ production, but not IL-17, which has been linked with inflammatory pathologies. Breast-resident Vδ1+ cells could be activated innately via the NKG2D receptor, whereas neighboring CD8+ αß T cells required TCR signaling. A comparable population of Vδ1+ cells was found in human breast tumors, and when paired tumor and nonmalignant samples from 11 patients with triple-negative breast cancer were analyzed, progression-free and overall survival correlated with Vδ1+ cell representation, but not with either total γδ T cells or Vδ2+ T cells. As expected, progression-free survival also correlated with αß TCRs. However, whereas in most cases TCRαß repertoires focused, typical of antigen-specific responses, this was not observed for Vδ1+ cells, consistent with their innate-like responsiveness. Thus, maximal patient benefit may accrue from the collaboration of innate-like responses mounted by tissue-resident Vδ1+ compartments and adaptive responses mounted by αß T cells.

Measurement of secondary cosmic-ray neutrons near the geomagnetic North Pole.

The spectrum of cosmogenic neutrons at Earth's surface covers a wide energy range, from thermal to several GeV. The flux of secondary neutrons varies with latitude, elevation, solar activity, and nearby material, including ground moisture. We report the results from a campaign to measure count rates in neutron detectors responding to three different energy ranges conducted near the geomagnetic North Pole at CFS Alert, Nunavut, Canada (82.5°N, 62.5°W; vertical geomagnetic cutoff rigidity, RC = 0 GV) in June of 2016. In November 2016, we performed a follow-on measurement campaign in southern Canada at similar RC (1.5 GV) and elevations. We conducted these measurements, at varying elevation and ground moisture content, with unmoderated and moderated 3He detectors for thermal and epithermal-to-MeV sensitivity, and with EJ-299-33 pulse shape discrimination plastic scintillator detectors for fast neutrons. Background gamma rays were monitored with NaI(Tl) detectors. Using these data sets, we compared the measured count rates to a predictive model. This is the first ever data set taken from this location on Earth. We find that for the thermal and epithermal-to-MeV neutron measurements the predictive model and data are in good agreement, except at one location on rock-covered ground near 1 km elevation. The discrepancy at that location may be attributable to ground moisture variability. Other measurements, during this campaign and prior, support the assertion that ground moisture plays a critical role in determining neutron flux.

How genetic variation affects patient response and outcome to therapy for psoriasis.

Psoriasis is a prevalent chronic inflammatory condition that affects the skin. There are many treatments available for psoriasis but they are not universally effective and some have associated toxicities. Pharmacogenetics and pharmacogenomics explore the relationship between individual genetic variation and drug effect to allow targeted 'personalized' therapy for patients. There has been very limited pharmacogenetic research regarding psoriasis, with most limited to small retrospective case-control studies looking at single-nucleotide polymorphisms in candidate genes involved in drug pharmacokinetics. We review the pharmacogenetic investigation of treatments for psoriasis to date, including emerging pharmacogenomic studies. In addition, we discuss how such genetic data could be incorporated into routine clinical practice and future areas for development in this field.

A gastrointestinal stromal tumour presenting incidentally with haemorrhage and perforation associated with a Meckel's diverticulum: a case report.

INTRODUCTION: This is the first reported case of perforation and haemorrhage of a Meckel's diverticulum leading to the incidental finding of a gastrointestinal stromal tumour within the diverticulum. Meckel's diverticulum is the most common congenital abnormality of the gastrointestinal tract, however, when symptomatic, it is often misdiagnosed at presentation. Common complications presenting in adults include bleeding, obstruction, diverticulitis and perforation. Tumours within a Meckel's diverticulum are a rare but recognised complication. We discuss the management of a gastrointestinal tumour within the diverticulum. CASE PRESENTATION: A 59-year-old Caucasian man presented with acute right iliac fossa pain with localized peritonism. At surgery, he was found to have a perforated and haemorrhagic Meckel's diverticulum, associated with a gastrointestinal stromal tumour within the apex of the diverticulum. The absence of necrosis and a low mitotic rate indicated primary resection with subsequent computed tomography surveillance to be the most appropriate management strategy. CONCLUSION: We report a unique triad of complications associated with the presentation of a Meckel's diverticulum. This article reviews this common congenital abnormality and discusses the management of a gastrointestinal tumour. Meckel's diverticulum will mimic other intra-abdominal pathologies in presentation and should therefore often be considered as a differential diagnosis.

IL-2 overcomes the unresponsiveness but fails to reverse the regulatory function of antigen-induced T regulatory cells.

Intranasal administration of peptide Ac1-9[4Y], based on the N-terminal epitope of myelin basic protein, can induce CD4(+) T cell tolerance, and suppress experimental autoimmune encephalomyelitis induction. The peptide-induced regulatory T (PI-T(Reg)) cells failed to produce IL-2, but expressed IL-10 in response to Ag and could suppress naive T cell responses in vitro. Analysis of Jak-STAT signaling pathways revealed that the activation of Jak1, STAT3, and STAT5 were induced in tolerant T cells after Ag stimulation in vivo. In addition, the expression of suppressor of cytokine signaling 3 was induced in tolerant T cells, suggesting that cytokines regulate the tolerant state of the PI-T(Reg) cells. Stimulation of PI-T(Reg) cells in vitro with IL-10 induced Jak1 and STAT3 activation, but not STAT5, suggesting that IL-10 is important, but not the only cytokine involved in the development of T cell tolerance. Although IL-2 expression was deficient, stimulation with IL-2 in vitro induced Jak1 and STAT5 activation in PI-T(Reg) cells, restored their proliferative response to antigenic stimulation, and abrogated PI-T(Reg)-mediated suppression in vitro. However, the addition of IL-2 could not suppress IL-10 expression, and the IL-2 gene remained inactive. After withdrawal of IL-2, the PI-T(Reg) cells regained their nonproliferative state and suppressive ability. These results underline the ability of the immune system to maintain tolerance to autoantigens, but at the same time having the ability to overcome the suppressive phenotype of tolerant T cells by cytokines, such as IL-2, during the protective immune response to infection.

The windlass mechanism during normal walking and passive first metatarsalphalangeal joint extension.

OBJECTIVE: To assess the relationship between passive first metatarsophalangeal extension and rearfoot motion during walking on the windlass mechanism. DESIGN: An in vivo study of the windlass mechanism during passive extension of the first metatarsophalangeal joint and walking. BACKGROUND: Despite theoretical work regarding the windlass mechanism in cadavers, there is little research concerning its in vivo role. METHODS: The amount of first metatarsophalangeal extension and medial longitudinal arch movement of the right foot in 20 subjects between the age of 22 and 55 years was recorded as they sat with their right hip, knee and ankle in 90 degrees and their great toe passively extended. In addition, movement of the rearfoot was recorded while they walked. RESULTS: The results of this study showed that the windlass mechanism is active during passive extension of the great toe. In addition, subjects could be divided into two groups (IMMEDIATE and DELAYED) based upon the timing of when the windlass mechanism began relative to passive extension of their first metatarsophalangeal joint. During walking, the DELAYED group was more inverted at heel strike and had a greater magnitude of rearfoot eversion. CONCLUSIONS: Two distinct subpopulations of individuals can be identified by when the windlass mechanism is initiated relative to passive first metatarsalphalangeal extension.