NK1 Receptor Research Articles

Interleukin-1A May Illuminate Differential Effects of the Retinal Artery Caliber in HIV Patients

Background: Retinal artery caliber (RAC) is narrower in human immunodeficiency virus (HIV)-infected patients beginning antiretroviral therapy (ART). We aimed to assess associations between variations in genes encoding inflammatory mediators and natural killer receptors and retinal artery caliber (RAC) in HIV patients beginning ART.Materials and Methods: Seventy-nine HIV positive patients beginning ART with less than 200 cluster of differentiation (CD) 4 T-cells/μL were recruited. Examinations were performed before ART (V0) and at months 3, 6 and 12 (V3, V6, V12). The study was approved by ethics committees and informed consent was obtained from each subject.Results: Right and left RAC of the HIV patients were narrower than healthy controls (p=0.016 for right RAC) and narrowed further on ART, but demographic associations with the right and left RAC were not identical. Here we show that polymorphisms in genes encoding NK receptors or TNF activity had no significant impact, but right RAC was associated with carriage of allele 2 at IL1A+4845 (p=0.037 after 12 months on ART).Conclusion: Overall the paradoxical reduction in the RAC in HIV patients responding to ART was not modified by genotypes known to affect NK cell function or TNF responses, but IL1A genotype may modify the decline in the right RAC.Keywords: anti-retroviral therapy, CMV, HIV, IL1A, retinal artery caliber

Chronic T cell receptor stimulation unmasks NK receptor signaling in peripheral T cell lymphomas via epigenetic reprogramming.

Peripheral T cell lymphomas (PTCLs) represent a significant unmet medical need with dismal clinical outcomes. The T cell receptor (TCR) is emerging as a key driver of T lymphocyte transformation. However, the role of chronic TCR activation in lymphomagenesis and in lymphoma cell survival is still poorly understood. Using a mouse model, we report that chronic TCR stimulation drove T cell lymphomagenesis, whereas TCR signaling did not contribute to PTCL survival. The combination of kinome, transcriptome, and epigenome analyses of mouse PTCLs revealed a NK cell-like reprogramming of PTCL cells with expression of NK receptors (NKRs) and downstream signaling molecules such as Tyrobp and SYK. Activating NKRs were functional in PTCLs and dependent on SYK activity. In vivo blockade of NKR signaling prolonged mouse survival, demonstrating the addiction of PTCLs to NKRs and downstream SYK/mTOR activity for their survival. We studied a large collection of human primary samples and identified several PTCLs recapitulating the phenotype described in this model by their expression of SYK and the NKR, suggesting a similar mechanism of lymphomagenesis and establishing a rationale for clinical studies targeting such molecules.

ADCC-Inducing Antibody Trastuzumab and Selection of KIR-HLA Ligand Mismatched Donors Enhance the NK Cell Anti-Breast Cancer Response.

Simple SummaryNatural killer (NK) cells are potent killers of tumor cells. Many tumors, including breast cancers, develop mechanisms to suppress anti-tumor immune responses, requiring the development of strategies to overcome suppression. Here, we tested a combination therapy that aims to (1) enhance NK cell activation and (2) reduce NK cell inhibition mediated by suppressive factors in tumors or in the tumor microenvironment. We cultured cell lines under hypoxia to mimic the tumor microenvironment or used patient-derived breast cancer cells that were primed by the patient’s tumor environment. Our results demonstrated that cytokine-activated NK cells remained active under hypoxia and that tumor-targeting antibodies enhanced the NK cell anti-breast cancer response. Moreover, we observed that NK cell suppression by inhibitory ligands on the tumor cells can be reduced by the selection of NK cell donors with NK receptors that are incompatible with these ligands. Collectively, we present two powerful strategies to enhance the NK cell responses against breast cancer.Natural killer (NK)-cell-based immunotherapies are an attractive treatment option for cancer. We previously showed that alloreactive mouse NK cells cured mice of 4T1 breast cancer. However, the tumor microenvironment can inhibit immune responses, and these suppressive factors must be overcome to unfold the NK cells’ full anti-tumor potential. Here, we investigated the combination of antibody-dependent cellular cytotoxicity (ADDC) and the selection of KIR-HLA-ligand mismatched NK cells to enhance NK cell anti-breast cancer responses in clinically relevant settings. Donor-derived and IL-2-activated NK cells were co-cultured with patient-derived breast cancer cells or cell lines MCF7 or SKBR3 together with the anti-HER2 antibody trastuzumab. NK cells mediated anti-breast cancer cytotoxicity under normoxic and hypoxic conditions. Under both conditions, trastuzumab vigorously enhanced NK cell degranulation (CD107a) against HER2-overexpressing SKBR3 cells, but we observed a discrepancy between highly degranulating NK cells and a rather modest increase in cytotoxicity of SKBR3. Against patient-derived breast cancer cells, the anti-tumor efficacy was rather limited, and HLA class I expression seemed to contribute to inhibited NK cell functionality. KIR-ligand-mismatched NK cells degranulated stronger compared to the matched NK cells, further highlighting the role of HLA. In summary, trastuzumab and KIR-ligand-mismatched NK cells could be two strategies to potently enhance NK cell responses to breast cancer.

NKp46 Is a Useful Diagnostic Biomarker in Gastrointestinal T-Cell Lymphoproliferative Diseases and Constitutes a Therapeutic Target. a Celac Network Study

Introduction:Primary gastrointestinal (GI) T-cell lymphoproliferative diseases (T-LPD) are heterogeneous entities, which diagnoses and therapeutic options remain to be standardized. Beside aggressive lymphoma, such as enteropathy-associated T-cell lymphoma (EATL) and monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), the indolent T-cell lymphoproliferative disease (indolent T-LPD) has been recently described. A differential diagnosis to consider is type II refractory coeliac disease (RCDII) that may complicate CD. Intraepithelial lymphocytes (IEL) from RCDII are dependent for survival on IL-15, which reprograms T-lymphocytes towards a cytotoxic NK phenotype. We previously showed that NKp46 is a new biomarker for both diagnosis and prognosis in GI T-LPD (ICML-2017 Lugano, unpublished).Patients and Methods:The expression of NK receptors was assessed on CD/RCD by flow-cytometry. The number of NKp46 positive IEL per 100 epithelial cells (NKp46+ IEL/100 EC) was studied by immunohistochemistry (IHC) on 195 biopsies from 84 CD/RCD, 44 GI T-cell lymphoma, and on a blinded confirmatory cohort of 48 CD/RCD.8B6A-PBD is an anti-NKp46 monoclonal antibody conjugated (ADC) to a potent cytotoxic drug, pyrrolobenzodiazepine (PBD). For in vivo assessment, tumor-bearing NOD-SCID mice were randomly assigned to PBS, isotype-matched irrelevant Ig-PBD controls, or 8B6A-PBD treatment groups. For ex vivo cytotoxicity assays, isolated cells from fresh small bowel biopsies of RCDII patients were incubated with 8B6A-PBD, Ig-PBD, anti-NKp46 deglycosylated or PBD alone.Results:NKp46 was the only NK receptor that differs between RCDII and CD or RCDI. By doing ROC analysis, a number of NKp46+ IEL/100 EC above 25 clearly discriminated RCDII from CD and RCDI, with excellent positive and negative predictive values of 100 and 95% respectively. Among CD and RCD patients, the survival was shorter if this count is above 25 (OS-5years 72.8% vs. 96.4%, P=0.0004). NKp46 was expressed in EATL (n=20/25) and MEITL (n=4/4) but was never expressed in indolent T-LPD (n=0/15). Positive NKp46 GI T-cell lymphoma had a shorter survival compared to negative NKp46 cases (OS-5years 5.4% vs. 50.5%, P=0.0011).In vivo the anti-NKp46-PBD promoted tumor regression (Fig. B) and prolonged survival (Fig. A) of NOD-SCID mice injected by human NKp46-transfected Raji tumors embedded in matrigel. Ex vivo and as a proof of concept, the anti-NKp46-PBD was highly potent (Fig. D) and selective (Fig. C) against NKp46 positive primary sorted IEL (n=5).Conclusion:NKp46 provides a new biomarker for both diagnosis and prognosis in GI T-LPD. We propose a diagnostic algorithm for GI T-LPD based on the NKp46 expression, which is adapted to immediate, individual patient management. Overall, our results demonstrate for the first time that anti-NKp46 ADC may serve as an effective therapy for RCDII, EATL and MEITL and provide strong preclinical rationale for evaluation of 8B6A-PBD in clinical studies. [Display omitted] DisclosuresCheminant:Innate Pharma: Research Funding. Bruneau:Innate Pharma: Research Funding. Malamut:Cellimmune: Research Funding. Pouyet:MI-mAbs: Employment. Lhospice:Innate Pharma: Employment. Molina:Merck Serono: Honoraria; Takeda: Other: travel support to the ASH meeting; Novartis: Honoraria. Cellier:Cellimmune: Research Funding. Cerf-Bensussan:Cellimmune: Research Funding. Hermine:Novartis: Research Funding; Celgene: Research Funding; AB Science: Equity Ownership, Honoraria, Patents & Royalties, Research Funding; Hybrigenics: Research Funding; INatherys: Equity Ownership, Research Funding.

Natural Killer Receptor Ligand Expression By AML Blasts Determines Survival and Relapse Following Induction Chemotherapy

IntroductionNatural killer (NK) cells contribute to the immune surveillance of cancer and are capable of controlling acute myeloid leukemia (AML) in vitro and following allogeneic hematopoietic stem cell transplantation. NK cell activation is dependent on the balance of activating and inhibitory receptor-ligand interactions. The prognostic impact of the expression of NK receptor ligands (NKRL) on AML blasts at diagnosis has not been described. We investigated the impact of NKRL expression by AML on the outcome of newly diagnosed patients undergoing induction chemotherapy. We hypothesized that patients with AML that expressed NKRL that facilitated NK cell activation (low inhibitory and high activating ligand expression) have improved immune surveillance and a reduced relapse rate.MethodsCryopreserved bone marrow cells and clinical data of 66 AML patients who underwent induction chemotherapy between 2001 and 2013 were obtained from the Australasian Leukemia Lymphoma Group tissue bank. Patients were stratified by cytogenetics (CG) and mutation status (European LeukemiaNet criteria, ELN). Expression (by relative fluorescence intensity - RFI) of 6 activating (MICA, MICAB, CD155, CD112, ULBP1, ULBP2/5/6) and 3 inhibitory (HLA class I, PD-L1 and PD-L2) NKRL on AML blasts was analyzed by flow cytometry. A net score of activating minus inhibitory ligands was calculated, which stratified patients into 2 groups: G0 (inhibitory pattern) and G1 (activating pattern).ResultsThe median age of patients was 56 years. Cytogenetic risk was adverse (13), intermediate (46) and favorable (7); ELN risk incorporating mutational profile was adverse (25), intermediate (15), and favorable (20). 79% of patients received an anthracycline in combination with cytarabine as induction therapy. Among activating ligands, the MICA, CD112 and ULBP1 were frequently expressed by AML blasts (79%, 80% and 82% of patients respectively), and also demonstrated the greatest intensity of expression (mean RFI of 3, 4.2 and 6.5 respectively). When analyzed individually, only ULBP1 expression was significantly associated with improved overall survival (OS) (p<0.05), relapse free survival (RFS) (p<0.05) and lower relapse incidence (RI) (p<0.005). The intensity of ULBP1 expression was significantly associated with improved OS, RFS and RI in a stepwise fashion. Patients with the highest ULBP1 expression had a reduced hazard ratio of death (HR 0.20, p<0.05) or relapse (HR 0.24, p<0.05) compared with non-expressors. PD-L2 expression on AML cells was higher and more frequent than PD-L1 (85% vs 5%). All AML variably expressed HLA class I. According to RFI, 32 patients were assigned to G0 and 34 to G1. There was no difference in patient age or distribution of CG or ELN risk categories between patients in G0 or G1 subgroups. G1 was significantly associated with lower relapse incidence than G0 (p<0.005, 2-year-RI: G1 28% vs G0 71%, Fig. 1). G1 was associated with higher RFS (log-rank p<0.05; at 2 years: G1 52% vs G0 20%; Fig 2) and improved OS (log rank p<0.05; at 2 years: G1 56% vs G0 29%; Fig 3). The G1 phenotype remained significantly associated with lower RI when taking into account either CG or ELN risk.ConclusionsWe have identified an immunological risk stratification method based on NKRL expression which is independent of established cytogenetic and molecular prognostic factors. Expression of activating NK cell receptor ligands by AML blasts is associated with superior survival and reduced relapse following induction chemotherapy. Our findings suggest that AML blasts are effective targets for NK cell-mediated immune surveillance, and support investigation into therapeutic strategies to enhance NK cell activation as a means of maintaining remission. [Display omitted] DisclosuresRitchie:Amgen Inc.: Honoraria.

Drugs for preventing postoperative nausea and vomiting in adults after general anesthesia: An abridged Cochrane network meta-analysis.

In this abridged version of the recently published Cochrane review on antiemetic drugs, we summarize its most important findings and discuss the challenges and the time needed to prepare what is now the largest Cochrane review with network meta-analysis in terms of the number of included studies and pages in its full printed form. We conducted a systematic review with network meta-analyses to compare and rank single antiemetic drugs and their combinations belonging to 5HT₃-, D₂-, NK₁-receptor antagonists, corticosteroids, antihistamines, and anticholinergics used to prevent postoperative nausea and vomiting in adults after general anesthesia. 585 studies (97 516 participants) testing 44 single drugs and 51 drug combinations were included. The studies' overall risk of bias was assessed as low in only 27% of the studies. In 282 studies, 29 out of 36 drug combinations and 10 out of 28 single drugs lowered the risk of vomiting at least 20% compared to placebo. In the ranking of treatments, combinations of drugs were generally more effective than single drugs. Single NK1 receptor antagonists were as effective as other drug combinations. Of the 10 effective single drugs, certainty of evidence was high for aprepitant, ramosetron, granisetron, dexamethasone, and ondansetron, while moderate for fosaprepitant and droperidol. For serious adverse events (SAEs), any adverse event (AE), and drug-class specific side effects evidence for intervention effects was mostly not convincing. There is high or moderate evidence for at least seven single drugs preventing postoperative vomiting. However, there is still considerable lack of evidence regarding safety aspects that does warrant investigation.

Modeling shows the NK3R antagonist, ACER-801, reduces treatment-induced vasomotor symptoms.

e13013 Background: Hot flashes or vasomotor symptoms (VMS) are a common side effect of hormone deprivation (HD) therapy. Up to 80 % of cancer patients treated with tamoxifen (antiestrogen treatment) or leuprolide (androgen deprivation) have VMS. In some cases, patients discontinue HD therapy due to VMS severity and lower quality of life; therefore, reducing VMS is critical for patient compliance. NK3 receptor (NK3R) antagonists have previously been shown to reduce VMS in postmenopausal women. ACER-801 is a candidate NK3R antagonist drug intended to alleviate VMS severity when used with HD therapy. We used Quantitative Systems Pharmacology (QSP) modeling to predict the likely efficacy of ACER-801 in patients on HD therapy and evaluate the potential of hepatic drug-drug interactions between ACER-801 and tamoxifen or leuprolide. Methods: The model is composed of KNDy neurons in the arcuate nucleus with NKB, dynorphin, and estradiol effects on KNDy neurons, HPG axis, sex hormones, and neuroendocrine feedback. ACER-801, tamoxifen, and leuprolide PK, PD, and hepatic metabolism are included in the model. The model was developed, qualified, and tested using literature data. A tamoxifen-treated postmenopausal female virtual patient (VP) and leuprolide-treated male VP were created based on typical patients included in clinical trials. VMS severity and frequency were estimated based on the level of NKB binding to NK3R. Results: In the male VP, simulated leuprolide administration induced hypertrophy of KNDy neurons and VMS over six months. Coadministration of ACER-801 with leuprolide reduced VMS frequency and severity to near 0 in short-term (5-week) simulations. Simulations predict ACER-801 will not alter leuprolide metabolism nor increase plasma testosterone concentrations. Tamoxifen treatment increased VMS by 15% in simulations with the postmenopausal VP. Coadministration of ACER-801 with tamoxifen in this VP reduced VMS by 75% compared to tamoxifen monotherapy. ACER-801 had minimal effects on plasma estradiol concentrations in the postmenopausal VP. Drug-drug interactions between ACER-801 and tamoxifen were dependent on the simulated bioavailability of ACER-801. Using current estimates of ACER-801 bioavailability in the model, the hepatic concentration of ACER-801 had limited effects on tamoxifen metabolism, which are not expected to necessitate dose adjustments. Conclusions: Using a QSP neurobiology model as a research tool enabled us to evaluate the efficacy of the NK3R antagonist, ACER-801, to treat HD therapy-induced VMS. Simulations show ACER-801 may be highly efficacious for the treatment of induced-VMS. The research provided estimates of DDI with ACER-801 and tamoxifen and what clinical experiments would be needed to confirm those estimates.

Olanzapine or dexamethasone, with 5-HT3 receptor antagonist and NK-1 receptor antagonist, to prevent nausea and vomiting induced by cisplatin-based doublet chemotherapy: A non-inferiority, prospective, multi-centered, randomized, controlled, phase III clinical trial.

TPS12133 Background: Chemotherapy-induced nausea and vomiting (CINV) is a common side effect of cancer treatments, and dexamethasone offers an advantage over placebo for protection against chemotherapy-induced emesis in both acute and delayed phases. However, its side effects are diverse including moderate to severe insomnia, hyperglycemia, dyspepsia and so on, which are gathering increasing concerns. What’s more, dexamethasone is not applicable to all cancer patients. The incidence of diabetes mellitus varies in different cancer which can reach up to 55.3%, and dexamethasone might not be a proper anti-emesis choice for them. Besides, dexamethasone delivery is always on debating when patients are receiving immunotherapy. However, all anti-emesis regimen recommended in guidelines are dexamethasone based. Alternative anti-emesis regimen are required. Studies have shown that olanzapine plays an important role in treating delayed, refractory, breakthrough nausea and vomiting. Thus, we initiated this prospective, multi-center, phase III study to validate the dexamethasone-free protocol: the non-inferiority role of applying olanzapine to prevent CINV instead of dexamethasone. Methods: This clinical trial started on February 3, 2020 is being conducted in 23 centres. All patients eligible are chemotherapy naïve and plan to receive cisplatin-containing regimen. Based on a 70% complete remission rate of previous study, to demonstrate a non-inferiority margin of 10%, 548 patients are required for two arms with the consideration of 5% of drop out and lost to follow-up (80% power,α = 0.05). Study design: Enrolled patients are randomized 1:1 into 2 arms to receive olanzapine or dexamethasone combined with 5-HT3 receptor antagonist (palonosetron, granisetron or ondansetron) and NK-1 receptor antagonist (aprepitant or fosaprepitant) from the first day of chemotherapy. Olanzapine (5mg) is delivered orally per night from day 1 to day 4. Dexamethasone (12 mg) is given orally or intravenously within 30 minutes before cisplatin administrated on day 1; on day 2-4, the orally or intravenously given dose of dexamethasone is 8 mg. The primary endpoint is complete remission rate of vomiting during the whole observation period (0-120 hours from the starting of first course chemotherapy delivery). The secondary endpoints are complete remission rate of vomiting during 25-120 hours from the starting of first course chemotherapy delivery and no nausea rate during the whole observation period. Besides, side effects will be recorded according protocol. Clinical trial information: NCT04437017.

Assessing duration of breakthrough chemotherapy-induced nausea and vomiting (CINV): A pooled study analysis of NEPA versus aprepitant.

12091 Background: The historical standard clinical trial endpoint for preventing chemotherapy-induced nausea and vomiting (CINV) has been assessment of complete response (CR: no emesis and no rescue medication use) over five days. Recent evaluations focused on the duration of breakthrough CINV suggest that long duration of CINV results in more lost work time and impaired activity and is also a strong predictor for CINV in subsequent cycles. A recent pooled analysis of three similarly designed registration trials of NEPA, a fixed oral combination NK1 receptor antagonist (RA) (netupitant)/5-HT3RA (palonosetron), showed significantly higher CR rates during the delayed phase (≥24-120h) for NEPA compared to an aprepitant (APR) regimen. In this post-hoc analysis, we evaluated the extent and duration of breakthrough CINV in these pooled studies. Methods: Chemotherapy-naïve patients who received cisplatin-based chemotherapy and antiemetic prophylaxis of either a single dose of NEPA plus dexamethasone (DEX) or a 3-day APR/5-HT3 RA/DEX regimen from three randomized, double-blind pivotal trials were included. Patients without a CR were defined as treatment failures. Extent of CINV was evaluated using proportions of patients with treatment failure, emesis, and significant nausea (defined as &gt;25 mm on a 100 mm visual analog scale). Over the 5-day overall phase, duration was categorized as 1-2, and ≥3 days. Pearson’s chi-square test was employed to compare risks between treatments for each duration category in each of the previously mentioned endpoints. Results: Among all 621 NEPA and 576 APR patients, a significantly greater proportion of APR patients experienced treatment failure, emesis, and significant nausea for ≥3 days. Specifically, among patients with treatment failure, 31% (41/134) who received NEPA and 43% (61/143) who received APR experienced breakthrough CINV for ≥3 days. Conclusions: Expanding on data suggesting single-day NEPA is more effective than 3-day APR in preventing delayed CINV, NEPA is also more effective in minimizing the extent and duration of CINV in patients with breakthrough emesis and nausea.[Table: see text]

Noninferiority study evaluating dexamethasone (DEX)-sparing regimens administered with NEPA, a fixed combination of netupitant and palonosetron, for the prevention of chemotherapy-induced nausea and vomiting (CINV) caused by high-dose cisplatin.

12093 Background: Corticosteroids such as DEX continue to play a key role for the prevention of CINV. Although they are generally considered safe when used in combination with other anti-emetic agents, corticosteroids can cause a range of side effects. To reduce the overall exposure to DEX in patients receiving cisplatin-based chemotherapy, we evaluated the non-inferiority of DEX on day 1, with or without low-dose DEX on days 2 and 3, combined with oral NEPA, a fixed combination of the NK1 receptor antagonist (RA), netupitant and 5-HT3 RA, palonosetron, compared with NEPA plus the guideline-recommended use of 4-day DEX (reference arm). Non-inferiority was met for both DEX-sparing regimens and the reference arm for the primary endpoint of complete response (CR: no emesis and no rescue use) during the overall (0-120h) phase post-chemotherapy. In this analysis secondary efficacy endpoints were evaluated for the single-dose DEX-sparing group versus the 4-day DEX arm. Methods: In this analysis from an open-label, multicenter study (ClinicalTrials.gov NCT04201769) chemotherapy-naïve patients undergoing high-dose cisplatin (≥70 mg/m2) received either NEPA and DEX (12 mg) on day 1 only or NEPA and DEX [12 mg on day 1 plus 4 mg twice daily on days 2-4 (DEX4)]. Efficacy endpoints included complete protection (CR plus no significant nausea), no emesis, and no significant nausea (&lt;25 mm on a 100 mm visual analog scale) during the acute (0-24h), delayed (&gt;24-120h) and overall phases. The non-inferiority margin was set at -15% difference (DEX1 minus DEX4). Results: One-hundred fifty-two patients, 76 in each arm, were included. Non-inferiority was met for the DEX1 arm and the DEX4 reference arm for all efficacy endpoints (Table). Conclusions: A simplified regimen of NEPA plus single-dose DEX offers comparable CINV prevention throughout 5 days post-chemotherapy with the advantage of sparing patients additional doses of DEX in the high emetic risk setting of cisplatin-based chemotherapy. Clinical trial information: NCT04201769. [Table: see text]

High Dose Intravenous IgG Therapy Modulates Multiple NK Cell and T Cell Functions in Patients With Immune Dysregulation.

Intravenous immunoglobulin (IVIG) is an effective immunomodulatory treatment for immune dysregulation diseases. However, the mechanisms by which it reduces systemic inflammation are not well understood. NK cell cytotoxicity is decreased by IVIG in women with reduced fertility, but IVIG effects on NK cells in immune dysregulation are less clear. We hypothesized that IVIG modulation of lymphocyte function, especially in NK cells, is important for resolution of inflammation. Our aim was to identify IVIG-induced changes in a cohort of patients with Kawasaki disease (KD) and those that occur broadly in pediatric patients with various immune dysregulatory diseases. Peripheral blood mononuclear cells (PBMCs) of patients with KD or autoimmune/inflammatory diseases were phenotyped pre and post high dose IVIG treatment by flow cytometry. In KD patients, after IVIG infusion Treg cell frequency and the proportion of activated CD25+ immunoregulatory CD56bright NK cells was increased, and multiple lymphocyte subsets showed increased expression of the lymphoid tissue homing receptor CD62L. Importantly, IVIG treatment decreased the frequency of cells expressing the degranulation marker CD107a among cytotoxic CD56dim NK cells, which was reflected in a significant reduction in target cell killing and in decreased production of multiple pro-inflammatory mediators. Interestingly, the activating receptor CD336 was expressed on a higher proportion of CD56bright NK cells after IVIG in both KD and autoimmune/inflammatory patients while other NK receptors were increased differentially in each cohort. In autoimmune/inflammatory patients IVIG induced the proliferation marker CD71 on a higher percentage of CD56dim NK cells, and in contrast to KD patients, CD107a+ cells were increased in this subset. Furthermore, when PBMCs were stimulated ex vivo with IL-2 or Candida antigen in autologous plasma, more of the CD4+ T cells of KD patients expressed CD25 after IVIG therapy but fewer cytotoxic T cells were degranulated based on CD107a expression. In summary, IVIG treatment in patients with immune dysregulation has multiple effects, especially on NK cell subsets and CD4+ T cells, which are compatible with promoting resolution of inflammation. These novel findings provide insight into the immunomodulatory actions of IVIG in autoimmune and inflammatory conditions.

Evaluation of tradipitant, a selective NK1 antagonist, on response to oxycodone in humans.

RationalePreclinical studies demonstrate that the NK1 receptor is involved in opioid reinforcement and withdrawal expression. Few studies have examined the impact of treatment with NK1 antagonists on opioid response in humans.ObjectiveTo explore the potential for a selective NK1 antagonist, tradipitant, to attenuate the abuse liability and reinforcing and analgesic effects of oxycodone in opioid-experienced individuals.MethodsParticipants with recreational opioid use, but without opioid physical dependence, were enrolled as inpatients for ~6 weeks (n = 8). A within-subject, double-blind, randomized, placebo-controlled, crossover design was employed. The pharmacodynamic response to intranasal oxycodone across a range of doses (0 to 30 mg) was examined during two counterbalanced maintenance periods (tradipitant 0 or 85 mg/bid). Oxycodone self-administration was assessed with a modified progressive ratio procedure, and analgesia was assessed with the cold pressor test.ResultsOxycodone produced significant and dose-related increases on a broad array of prototypic opioid measures, including subjective ratings related to abuse liability (e.g., liking) and physiological outcomes (i.e., expired CO2). Oxycodone self-administration increased with increasing dose, as did analgesia. Tradipitant largely did not alter any of these effects of oxycodone, with the exception of producing a reduction in ratings of desire for opioids.ConclusionsGiven that the vast majority of oxycodone effects were unchanged by tradipitant, these data do not provide support for the utility of NK1 antagonists as a potential treatment for opioid use disorder.

New Drugs on the Horizon for Functional and Motility Gastrointestinal Disorders

New Drugs on the Horizon for Functional and Motility Gastrointestinal Disorders

Angiotensin (1-7) Attenuates the Nociceptive Behavior Induced by Substance P and NMDA via Spinal MAS1.

The intrathecal (i.t.) injection of substance P (SP) and N-methyl-D-aspartate (NMDA) induce transient nociceptive response by activating neurokinin (NK) 1 and NMDA receptors, respectively. We have recently reported that angiotensin (Ang) (1-7), an N-terminal fragment of Ang II, could alleviate several types of pain including neuropathic and inflammatory pain by activating spinal MAS1. Here, we investigated whether Ang (1-7) can inhibit the SP- and NMDA-induced nociceptive response. The nociceptive response induced by an i.t. injection of SP or NMDA was assessed by measuring the duration of hindlimb scratching directed toward the flank, biting and/or licking of the hindpaw or the tail for 5 min. Localization of MAS1 and either NK1 or NMDA receptors in the lumbar superficial dorsal horn was determined by immunohistochemical observation. The nociceptive response induced by SP and NMDA was attenuated by the i.t. co-administration of Ang (1-7) (0.03-3 pmol) in a dose-dependent manner. The inhibitory effects of Ang (1-7) (3 pmol) were attenuated by A779 (100 pmol), a MAS1 antagonist. Moreover, immunohistochemical analysis showed that spinal MAS1 co-localized with NK1 receptors and NMDA receptors on cells in the dorsal horn. Taken together, the i.t. injection of Ang (1-7) attenuated the nociceptive response induced by SP and NMDA via spinal MAS1, which co-localized with NK1 and NMDA receptors. Thus, the spinal Ang (1-7)/MAS1 pathway could represent a therapeutic target to effectively attenuate spinal pain transmission caused by the activation of NK1 or NMDA receptors.

Identification of porcine ileal innate lymphoid cells using single-cell RNA sequencing

Abstract Innate lymphoid cells (ILCs) are integral in maintaining intestinal defense and homeostasis, but intestinal ILCs have not been identified in pigs. Pigs are an important global food source and human biomedical model, thus identifying and characterizing porcine intestinal ILCs can have broad implications. Single-cell RNA sequencing of porcine ileal lymphocytes yielded 31,983 cells distributed across 54 clusters. Five clusters were closely related to T cell clusters yet lacked expression of the pan-T cell marker, CD3E. One cluster had high expression of genes related to type 3 immunity, including IL22, RORC, and CXCL8, indicating identification of putative ILC3s. The other four clusters expressed genes encoding for NK receptors (KLRK1, KLRC1, KLRD1) and effector molecules (CCL5, PRF1), yet they lacked expression of genes traditionally expressed by porcine NK cells (CD8A, KLRB1, HCST). Thus, we putatively identified the four clusters as ILC1s. Profiles of putative porcine ILC clusters were further compared to transcriptomic signatures of murine intestinal ILC subsets. Results indicated a relative enrichment of murine ILC3 gene signatures in the porcine ILC3 cluster, while relative enrichment of murine ILC1 gene signatures was observed for the other four clusters of porcine ILC1s. We further utilized single-cell gene expression profiles to develop a gating strategy to identify porcine intestinal ILCs as CD45+CD2+CD3ɛ−CD79α− lymphocytes at the protein level by flow cytometry. Altogether, the data allowed us to create the first transcriptomic descriptions of porcine intestinal ILCs and develop approaches to identify ILCs at the protein level, which will be applicable for future research.

The inhibitory NK receptor Ly49Q protects plasmacytoid dendritic cells from pyroptotic cell death

Ly49Q is an ITIM-bearing MHC class I receptor that is highly expressed in plasmacytoid dendritic cells (pDCs). Ly49Q is required for the TLR9-mediated IFN-I production in pDCs, although the mechanism is not fully understood. We here demonstrate that Ly49Q protects pDCs from pyroptotic cell death induced by CpG oligodeoxynucleotides (CpG). In the Ly49Q-deficient (Klra17−/−) mouse spleen, the number of ssDNA-positive pDCs increased significantly after CpG treatment, strongly suggesting that Klra17−/− pDCs were susceptible to CpG-induced cell death. In Klra17−/− bone-marrow-derived dendritic cells (BMDCs), CpG-induced cell death was accompanied by increased cathepsin B leakage from the vesicular compartments into the cytoplasm. Concurrently, IL-1β secretion increased in the CpG-treated Klra17−/− BMDCs, strongly suggesting that the CpG-induced cell death in these cells is pyroptotic in nature. Consistent with these observations, inhibiting cathepsin B or caspase 1 in CpG-stimulated Klra17−/− BMDCs reversed the increase in cell death. Pyroptotic cell death and IL-1β secretion were also observed in BMDCs derived from transgenic mice expressing an ITIM-less Ly49Q (Ly49Q-YF Tg). CpG also increased the IL-1β production and cell death in B2m−/− BMDCs. These results suggest that Ly49Q and MHC class I play important roles for protecting pyroptosis-like cell death of DCs by influencing lysosome state.

NK1 antagonists attenuate tau phosphorylation after blast and repeated concussive injury

Exposure to repeated concussive traumatic brain injury (TBI) and to blast-induced TBI has been associated with the potential development of the neurodegenerative condition known as chronic traumatic encephalopathy (CTE). CTE is characterized by the accumulation of hyperphosphorylated tau protein, with the resultant tau tangles thought to initiate the cognitive and behavioral manifestations that appear as the condition progresses. However, the mechanisms linking concussive and blast TBI with tau hyperphosphorylation are unknown. Here we show that single moderate TBI, repeated concussive TBI and blast-induced mild TBI all result in hyperphosphorylation of tau via a substance P mediated mechanism. Post-injury administration of a substance P, NK1 receptor antagonist attenuated the injury-induced phosphorylation of tau by modulating the activity of several key kinases including Akt, ERK1/2 and JNK, and was associated with improvement in neurological outcome. We also demonstrate that inhibition of the TRPV1 mechanoreceptor, which is linked to substance P release, attenuated injury-associated tau hyperphosphorylation, but only when it was administered prior to injury. Our results demonstrate that TBI-mediated stimulation of brain mechanoreceptors is associated with substance P release and consequent tau hyperphosphorylation, with administration of an NK1 receptor antagonist attenuating tau phosphorylation and associated neurological deficits. NK1 antagonists may thus represent a pharmacological approach to attenuate the potential development of CTE following concussive and blast TBI.

Involvement of 5-Serotonin and Substance p Pathways in Dichroa Alkali Salt-Induced Acute Pica in Rats.

Dichroa alkali salt (DAS) is the active ingredient of Changshan, a traditional Chinese antimalarial medicine. However, owing to its vomiting side effects, its clinical use is limited. Recently, DAS-induced vomiting has attracted broad attention; however, the mechanisms involved have not yet been elucidated. The present study aimed to explore DAS induced vomiting and decipher the potential role of the 5-serotonin (5-HT) and substance p (SP) signaling pathways. We used a combination of approaches in the context of a rat pica model, such as immunoblot analysis, HPLC-ECD, ELISA, quantitative real-time PCR, pharmacological inhibition, and immunohistochemistry assays. We demonstrated that DAS contributed to Changshan-induced vomiting via the activation of the 5-HT and SP signaling pathways. DAS could induce a dose-dependent kaolin intake in the rat pica model. Moreover, DAS caused a similar profile as Cisplatin (DDP): “low-dose double-peak, high-dose single-peak pica phenomenon”. Interestingly, treatment with DAS stimulated the peripheral ileum and central medulla oblongata and augmented the release of 5-HT, SP, and preprotachykinin-A and the expression of 5-HT3 and NK1 receptors in the two issues in acute phase. Additionally, the 5-HT3 and NK1 receptor antagonists effectively alleviated DAS-induced kaolin intake and significantly reduced DAS-induced 5-HT and SP levels in the two issues in acute phase. Similar responses were not observed in the context of dopamine receptor inhibition. This study innovatively revealed that the 5-HT and SP-mediated vomiting network plays an important role in DAS-induced acute vomiting; of note, ondansetron, and aprepitant can effectively antagonize DAS-induced vomiting. Our results suggest a potential therapeutic strategy (based on drugs approved for human use) to prevent the DAS-associated adverse reactions.

Platinum-induced nausea and vomiting in patients treated for head and neck cancer

Swallowing difficulties in patients with advanced head and neck cancer (HNC) represent an obstacle to adequate antiemetic prophylaxis before chemotherapy. We aim to assess chemotherapy-induced nausea and vomiting (CINV) risk in HNC patients in our center, with a specific focus among patients who could not receive appropriate NK1 receptor antagonist (NK1-RA) prophylaxis. Prospective observational monocentric study. CINV were evaluated with the MASCC Antiemesis Tool self-questionnaire (MAT) for all patients treated by platinum-based chemotherapy for advanced HNC (January-April 2019), thereafter, only for patients without NK1-RA prophylaxis due to swallowing difficulties were included (May-October 2019). Sixty-one patients were included (82% male, 49.2% reccurent/metastatic disease), 18 did not received NK1-RA prophylaxis due to swallowing difficulties. Among 52 patients included from January to April 2019, 17.3% reported swallowing difficulties. The chemotherapy regimen was highly and moderately emetic for 40 (65.6%) and 21 patients (34.4%), respectively. CINV was associated with both cisplatin-based chemotherapy (OR 10.66, 95% CI [2.17-52.08]) and exclusive chemotherapy (OR 7.76, 95% CI [1.79-33.78]). Patients who did not receive anti-NK1 prophylaxis had no more CINV than patients with adequate CINV prophylaxis. CINV remains frequent in patients treated by platinum-based chemotherapy for HNC. Oral NK1-RA prophylaxis can be unavailable because of swallowing difficulties, without an increased risk of CINV.

Simulation of the oxidative metabolization pattern of netupitant, an NK1 receptor antagonist, by electrochemistry coupled to mass spectrometry

Considering the frequent use of netupitant in polytherapy, the elucidation of its oxidative metabolization pattern is of major importance. However, there is a lack of published research on the redox behavior of this novel neurokinin-1 receptor antagonist. Therefore, this study was performed to simulate the intensive hepatic biotransformation of netupitant using an electrochemically driven method. Most of the known enzyme-mediated reactions occurring in the liver (i.e., N-dealkylation, hydroxylation, and N-oxidation) were successfully mimicked by the electrolytic cell using a boron-doped diamond working electrode. The products were separated by reversed-phase high-performance liquid chromatography and identified by high-resolution mass spectrometry. Aside from its ability to pinpoint formerly unknown metabolites that could be responsible for the known side effects of netupitant or connected with any new perspective concerning future therapeutic indications, this electrochemical process also represents a facile alternative for the synthesis of oxidation products for further in vitro and in vivo studies.