Comparative whole genome analysis of face-derived Streptococcus infantis CX-4 unravels the functions related to skin barrier

BACKGROUND

The skin microbiome is essential in guarding against harmful pathogens and responding to environmental changes by generating substances useful in the cosmetic and pharmaceutical industries. Among these microorganisms, Streptococcus is a bacterial species identified in various isolation sources. In 2021, a strain of Streptococcus infantis, CX-4, was identified from facial skin and found to be linked to skin structure and elasticity. As the skin-derived strain differs from other S. infantis strains, which are usually of oral origin, it emphasizes the significance of bacterial variation by the environment.

OBJECTIVE

This study aims to explore the unique characteristics of the CX-4 compared to seven oral-derived Streptococcus strains based on the Whole-Genome Sequencing data, focusing on its potential role in skin health and its possible application in cosmetic strategies.

METHODS

The genome of the CX-4 strain was constructed using PacBio Sequencing, with the assembly performed using the SMRT protocol. Comparative whole-genome analysis was then performed with seven closely related strains, utilizing web-based tools like PATRIC, OrthoVenn3, and EggNOG-mapper, for various analyses, including protein association analysis using STRING.

RESULTS

Our analysis unveiled a substantial number of Clusters of Orthologous Groups in diverse functional categories in CX-4, among which sphingosine kinase (SphK) emerged as a unique product, exclusively present in the CX-4 strain. SphK is a critical enzyme in the sphingolipid metabolic pathway, generating sphingosine-1-phosphate. The study also brought potential associations with isoprene formation and retinoic acid synthesis, the latter being a metabolite of vitamin A, renowned for its crucial function in promoting skin cell growth, differentiation, and maintaining of skin barrier integrity. These findings collectively suggest the potential of the CX-4 strain in enhancing of skin barrier functionality.

CONCLUSION

Our research underscores the potential of the skin-derived S. infantis CX-4 strain by revealing unique bacterial compounds and their potential roles on human skin.

Enhancement of anti-tumor activity in melanoma using arginine deiminase fused with 30Kc19α protein

Arginine deiminase (ADI) is a microbial-derived enzyme which catalyzes the conversion of L-arginine into L-citrulline. ADI originating from Mycoplasma has been reported to present anti-tumor activity against arginine-auxotrophic tumors, including melanoma. Melanoma cells are sensitive to arginine depletion due to reduced expression of argininosuccinate synthase 1 (ASS1), a key enzyme for arginine biosynthesis. However, clinical applications of recombinant ADI for melanoma treatment present some limitations. Since recombinant ADI is not human-derived, it shows instability, proteolytic degradation, and antigenicity in human serum. In addition, there is a problem of drug resistance issue due to the intracellular expression of once-silenced ASS1. Moreover, recombinant ADI proteins are mainly expressed as inclusion body forms in Escherichia coli and require a time-consuming refolding process to turn them back into active form. Herein, we propose fusion of recombinant ADI from Mycoplasma hominis and 30Kc19α, a cell-penetrating protein which also increases stability and soluble expression of cargo proteins, to overcome these problems. We inserted matrix metalloproteinase-2 cleavable linker between ADI and 30Kc19α to increase enzyme activity in melanoma cells. Compared to ADI, ADI-LK-30Kc19α showed enhanced solubility, stability, and cell penetration. The fusion protein demonstrated selective cytotoxicity and reduced drug resistance in melanoma cells, thus would be a promising strategy for the improved efficacy in melanoma treatment. KEY POINTS: • Fusion of ADI with 30Kc19α enhances soluble expression and productivity of recombinant ADI in E. coli • 30Kc19α protects ADI from the proteolytic degradation by shielding effect, helping ADI to remain active • Intracellular delivery of ADI by 30Kc19α overcomes ADI resistance in melanoma cells by degrading intracellularly expressed arginine.

Bone regeneration at extraction sockets filled with leukocyte-platelet-rich fibrin: An experimental pre-clinical study

Background

We aimed to histomorphometrically evaluate the effects of Leucocyte-Platelet-Rich Fibrin (L-PRF), with and without the combination of a bone grafting material, for alveolar ridge preservation using an in vivo canine model.

Material and Methods

Seven dogs (Female Beagles, ~18-month-old) were acquired for the study. L-PRF was prepared from each individual animal by drawing venous blood and spinning them through a centrifuge at 408 RCF-clot (IntrasSpin, Intra-Lock, Boca Raton, FL). L-PRF membranes were obtained from XPression fabrication kit (Biohorizons Implant Systems, Inc., AL, USA). A split mouth approach was adopted with the first molar mesial and distal socket defects treated in an interpolated fashion of the following study groups: 1) Empty socket (negative control); 2) OSS filled defect 3) L-PRF membrane; and 4) Mix of Bio-Oss® with L-PRF. After six weeks, samples were harvested, histologically processed, and evaluated for bone area fraction occupancy (BAFO), vertical/horizontal ridge dimensions (VRD and HRD, respectively), and area of coronal soft tissue infiltration.

Results

BAFO was statistically lower for the control group in comparison to all treatment groups. Defects treated with Bio-Oss® were not statistically different then defects treated solely with L-PRF. Collapsed across all groups, L-PRF exhibited higher degrees of BAFO than groups without L-PRF. Defects filled with Bio-Oss® and Bio-Oss® with L-PRF demonstrated greater maintenance of VRD relative to the control group. Collapsed across all groups, Bio-Oss® maintained the VRD and resulted in less area of coronal soft tissue infiltration compared to the empty defect. Soft tissue infiltration observed at the coronal area was not statistically different among defects filled with L-PRF, Bio-Oss®, and Bio-Oss® with L-PRF.

Conclusions

Inclusion of L-PRF to particulate xenograft did not promote additional bone heading at 6 weeks in vivo. However, we noted that L-PRF alone promoted alveolar socket regeneration to levels comparable to particulate xenografts, suggesting its potential utilization for socket preservation.

Key words:L-PRF, bone healing, socket preservation.

AB0344 EFFICACY OF SUBCUTANEOUS INFLIXIMAB (CT-P13 SC) COMPARED WITH INTRAVENOUS INFLIXIMAB IN RHEUMATOID ARTHRITIS: A POST-HOC ANALYSIS OF A PHASE 3 RANDOMIZED CONTROLLED TRIAL

Background

Subcutaneous (SC) CT-P13 is the first and only subcutaneous formulation of infliximab (IFX) approved by the EMA.1 In the pivotal study (NCT03147248), non-inferiority of SC IFX to intravenous (IV) was demonstrated in rheumatoid arthritis (RA) patients using 28-joint Disease Activity Score (DAS28) C-reactive protein (CRP) improvement at Week 22, with a statistically significant treatment difference of 0.27 (95% CI 0.02, 0.52) favoring the SC versus the IV arm.2,3 At Week 30, numerical differences in efficacy outcomes were shown between SC and IV IFX favoring SC IFX. IV group patients switched to SC IFX by Week 30, and the difference between the groups was reduced at Week 54.2

Objectives

To investigate whether there was a statistically significant difference between SC and IV IFX at Weeks 30 and 54 in the phase 3 pivotal study of CT-P13 SC using conservative missing imputation methods.

Methods

Patients with active RA who had an inadequate response to MTX received IV IFX 3mg/kg at Weeks 0 and 2 for induction and were randomized at a 1:1 ratio to receive SC IFX 120mg every 2 weeks or IV 3mg/kg every 8 weeks thereafter for maintenance. Patients who were randomized to receive IV IFX switched to SC at Week 30. In this post-hoc analysis, non-responder imputation (NRI) and last observation carried forward (LOCF) methods were used to investigate whether the difference in efficacy outcomes between SC and IV IFX at Weeks 30 and 54 was statistically significant. Assessments included EULAR (CRP/ESR)/ACR response; remission rate and low disease activity (LDA) rate based on DAS28 (CRP/ESR), Clinical Disease Activity Index (CDAI) and Simplified Disease Activity Index (SDAI); Boolean remission rate; and the proportion of patients achieving a minimal clinically important difference (MCID) in Health Assessment Questionnaire (HAQ).

Results

Of the 343 randomized patients, 165 patients who received SC IFX and 174 patients who received IV IFX from the efficacy population were included in the analysis. There was a statistically significant difference in SC IFX compared to IV treated patients at Week 30 using both NRI and LOCF methods in almost all the clinical variables. However, the difference in efficacy outcomes between SC IFX and IV was reduced at Week 54 after the IV group switched to SC. This supports the improved efficacy of SC IFX at Week 30. Some of the key results (EULAR [CRP] responses, LDA rates based on DAS28 [CRP], CDAI, and SDAI) were presented in Figure 1. Analysis using LOCF and NRI methods yielded consistent results across most of the efficacy outcomes.

Figure 1.

Comparison of clinical outcomes between SC IFX and IV IFX in patients with active rheumatoid arthritis.

*P<0.05.

P-value for difference in proportion between SC and IV treatment group was obtained by asymptotic Wald test.

Low disease activity based on DAS28 (CRP) (< 3.2), CDAI (eatment group AI (≤ 11.0).

Conclusion

Statistical analyses using conservative missing imputation methods showed significantly greater improvements in clinical outcomes with SC IFX compared to IV at Week 30 in patients with RA. Between-group differences was reduced at Week 54, suggesting improved responses after switching from IV to SC.

References

[1]Remsima summary of product characteristics. https://www.ema.europa.eu/en/documents/product-information/remsima-epar-product-information_en.pdf. Published 2021. Accessed 10 January 2022.

[2]Westhovens R, Wiland P, Zawadzki M, et al. Efficacy, pharmacokinetics and safety of subcutaneous versus intravenous CT-P13 in rheumatoid arthritis: a randomized phase I/III trial. Rheumatology (Oxford). 2021;60(5):2277-2287.

[3]Combe B, Allanore Y, Alten R, et al. Comparative efficacy of subcutaneous (CT-P13) and intravenous infliximab in adult patients with rheumatoid arthritis: a network meta-regression of individual patient data from two randomised trials. Arthritis Res Ther. 2021;23(1):119.

Disclosure of Interests

Arnaud Constantin Speakers bureau: Abbvie, Amgen, Boehringer, Celltrion, Galapagos, Janssen, Lilly, Novartis, Sanofi, UCB, Consultant of: Abbvie, Amgen, Boehringer, Celltrion, Galapagos, Janssen, Lilly, Novartis, Sanofi, UCB, Roberto Caporali Speakers bureau: Abbvie, Amgen, BMS, Celltrion, Galapagos, Lilly, Pfizer, Fresenius-Kabi, MSD, UCB, Roche,Janssen, Novartis, Sandoz, Consultant of: Abbvie, Amgen, BMS, Celltrion, Galapagos, Lilly, Pfizer, MSD, UCB, Janssen, Novartis, Sandoz, Christopher John Edwards Speakers bureau: Abbvie, Astra Zeneca, Celltrion, Chugai, Fresenius, Galapagos, Gilead, GSK, Lilly, Janssen, Pfizer, Roche, Consultant of: Abbvie, Astra Zeneca, Chugai, Galapagos, Gilead, GSK, Lilly, Janssen, Pfizer, Roche, Grant/research support from: Celltrion, Pfizer, Abbvie, Joao Eurico Fonseca Speakers bureau: Abbvie, Ache, Janssen, Lilly, Medac, Novartis, Pfizer, Consultant of: Abbvie, Celltrion, Janssen, Lilly, Pfizer, Grant/research support from: Abbvie, Janssen, Lilly, MSD, Novartis, Pfizer, Roche, Florenzo Iannone Speakers bureau: Abbvie, BMS, Celltrion, Galapagos, MSD, Eli-Lilly, Janssen, Novartis, Pfizer, UCB, Consultant of: Abbvie, BMS, Celltrion, Galapagos, MSD, Eli-Lilly, Janssen, Pfizer, Grant/research support from: BMS, MSD, Edward Keystone Speakers bureau: Amgen, AbbVie, Celltrion, F. Hoffmann-La Roche Inc., Janssen Inc., Merck, Pfizer Pharmaceuticals, Sandoz, Sanofi Genzyme, Consultant of: AbbVie, Amgen, Celltrion, Myriad Autoimmune, F. Hoffmann-La Roche Inc, Janssen Inc, Lilly Pharmaceuticals, Merck, Pfizer Pharmaceuticals, Sandoz, Sanofi-Genzyme, Samsung Bioepsis, Grant/research support from: Amgen, Merck, Pfizer Pharmaceuticals, Hendrik Schulze-Koops Consultant of: Celltrion, Taeksang Kwon Employee of: Celltrion Healthcare, Seungmin Kim Employee of: Celltrion Healthcare, Sangwook Yoon Employee of: Celltrion Healthcare, Dong-Hyeon Kim Employee of: Celltrion Healthcare, Gahee Park Employee of: Celltrion Inc., DaeHyun Yoo Speakers bureau: Celltrion, Celltrion Healthcare

Supercomputer-Based Ensemble Docking Drug Discovery Pipeline with Application to Covid-19

We present a supercomputer-driven pipeline for in silico drug discovery using enhanced sampling molecular dynamics (MD) and ensemble docking. Ensemble docking makes use of MD results by docking compound databases into representative protein binding-site conformations, thus taking into account the dynamic properties of the binding sites. We also describe preliminary results obtained for 24 systems involving eight proteins of the proteome of SARS-CoV-2. The MD involves temperature replica exchange enhanced sampling, making use of massively parallel supercomputing to quickly sample the configurational space of protein drug targets. Using the Summit supercomputer at the Oak Ridge National Laboratory, more than 1 ms of enhanced sampling MD can be generated per day. We have ensemble docked repurposing databases to 10 configurations of each of the 24 SARS-CoV-2 systems using AutoDock Vina. Comparison to experiment demonstrates remarkably high hit rates for the top scoring tranches of compounds identified by our ensemble approach. We also demonstrate that, using Autodock-GPU on Summit, it is possible to perform exhaustive docking of one billion compounds in under 24 h. Finally, we discuss preliminary results and planned improvements to the pipeline, including the use of quantum mechanical (QM), machine learning, and artificial intelligence (AI) methods to cluster MD trajectories and rescore docking poses.

Supercomputer-Based Ensemble Docking Drug Discovery Pipeline with Application to Covid-19

We present a supercomputer-driven pipeline for in-silico drug discovery using enhanced sampling molecular dynamics (MD) and ensemble docking. We also describe preliminary results obtained for 23 systems involving eight protein targets of the proteome of SARS CoV-2. THe MD performed is temperature replica-exchange enhanced sampling, making use of the massively parallel supercomputing on the SUMMIT supercomputer at Oak Ridge National Laboratory, with which more than 1ms of enhanced sampling MD can be generated per day. We have ensemble docked repurposing databases to ten configurations of each of the 23 SARS CoV-2 systems using AutoDock Vina. We also demonstrate that using Autodock-GPU on SUMMIT, it is possible to perform exhaustive docking of one billion compounds in under 24 hours. Finally, we discuss preliminary results and planned improvements to the pipeline, including the use of quantum mechanical (QM), machine learning, and AI methods to cluster MD trajectories and rescore docking poses.

OP0046 TARGETING IRAK1 AND 4 SIGNALING WITH R835, A NOVEL ORAL SMALL MOLECULE INHIBITOR: A POTENTIAL NEW TREATMENT FOR SYSTEMIC LUPUS ERYTHEMATOSUS

Background:

Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by loss of immunological tolerance, hyperactivation of immune cells, proinflammatory cytokine production and, ultimately, end organ damage due to immune complex deposition. Toll-like receptors (TLRs), which are essential to the innate immune response to microbes and other danger signals, play a key role in the pathogenesis of SLE by recognition of self-molecules (1). Interleukin receptor associated kinases (IRAK)1 and 4 are responsible for initiating MyD88-dependent signaling from most TLRs and Interleukin-1 Receptors (IL-1R) and represent attractive targets for the therapeutic treatment of SLE (2). We have identified a potent and selective IRAK1/4 inhibitor, R835, that substantially suppressed the elevation of LPS (TLR4 agonist)-induced serum cytokines in healthy human volunteers in a recently completed phase 1 study.

Objectives:

The aim of our study was to investigate the effect of IRAK1/4 selective inhibition as potential therapeutic approach for SLE. We evaluated the effect of our clinical candidate R835 on TLR7 signaling and in a mouse model of lupus-like disease.

Methods:

Human primary dendritic cells and whole blood were stimulated with gardiquimod (TLR7 agonist) to evaluate the effect of R835 on Interferon-alpha (IFN-α) production. R835 was further evaluated for its efficacy on survival and disease progression in lupus-prone NZB/W F1 mice with early or active signs of disease.

Results:

R835 inhibited TLR7-induced cytokine production in human dendritic cells and whole blood. Given orally to mice, R835 dose-dependently decreased serum IFN-α in response to administration of a TLR7 agonist. Furthermore, treatment of NZB/W F1 lupus-prone mice with R835 reversed the progression of lupus-like disease and the establishment of a pro-inflammatory environment, as demonstrated by decreased levels of proteinuria, blood urea nitrogen and autoantibodies, and reversal of renal pathology.

Conclusion:

To our knowledge, R835 is the first dual IRAK1/4 inhibitor to enter clinical development and provides an attractive approach to treat a range of autoimmune and rheumatic diseases, including lupus.

References:

[1]Signals via the Adaptor MyD88 in B cells and DCs Make Distinct and Synergistic Contributions to Immune Activation and Tissue Damage in Lupus. Lino L. Teichmann, Dominik Schenten, Ruslan Medzhitov, Michael Kashgarian, and Mark J. Shlomchik. Immunity. 2013 March 21; 38(3): 528–540.

[2]Suppression of IRAK1 or IRAK4 Catalytic Activity, but Not Type 1 IFN Signaling, Prevents Lupus Nephritis in Mice Expressing a Ubiquitin Binding-Defective Mutant of ABIN1. Nanda SK, Lopez-Pelaez M, Arthur JS, Marchesi F, Cohen P. J Immunol. 2016 Dec 1;197(11):4266-4273.

Disclosure of Interests:

Chrystelle Lamagna Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Meagan Chan Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Art Bagos Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Ernest Tai Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Chi Young Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Yan Chen Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Lu Chou Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Gary Park Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Esteban Masuda Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Vanessa Taylor Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals

OP0133 PRECLINICAL EFFICACY OF R835, A NOVEL IRAK1/4 DUAL INHIBITOR, IN RODENT MODELS OF JOINT INFLAMMATION

Background:

Interleukin receptor associated kinases (IRAK) 1 and 4 are kinases involved in Toll-Like Receptor (TLR) and Interleukin-1 Receptor (IL-1R) signaling pathways, which regulate innate immunity and inflammation. Dysregulation of IRAK1/4 signaling can lead to a variety of inflammatory conditions including rheumatoid and gouty arthritis. As a result, IRAK1/4 are promising therapeutic targets for rheumatic diseases (1). We have identified a potent and selective IRAK1/4 inhibitor, R835, that substantially suppressed the elevation of LPS (TLR4 agonist)-induced serum cytokines in healthy human volunteers in a recently completed phase 1 study.

Objectives:

The aim of our study was to investigate the effect of IRAK1/4 selective inhibition as a potential therapeutic approach for rheumatological diseases. We evaluated the inhibition by our clinical candidate, R835, on TLR-, IL-1R- and NLRP3 inflammasome-induced cytokine production, as well as in preclinical models of arthritis.

Methods:

The effect of R835 on TLR- or IL-1R-induced cytokine production was evaluated in vitro using THP-1, human primary endothelial cells and human primary dendritic cells. The activity of R835 on the NLRP3 inflammasome was also tested in vitro using THP-1 cells. The pharmacokinetic-pharmacodynamic relationship of R835 was evaluated in a mouse model of IL-1b-induced cytokine release. Mice were pre-treated orally with vehicle or R835 prior to challenge; serum cytokine and plasma compound levels were determined. The efficacy of IRAK1/4 inhibition by R835 in rodent models of joint inflammation was evaluated in a mouse model monosodium (MSU)-induced peritonitis, in rat model of MSU-induced gouty arthritis and in a rat model of collagen-induced arthritis (CIA).

Results:

In human cells, R835 blocked proinflammatory cytokine production in response to TLR, IL-1R and NLRP3 inflammasome activation. In mice, R835 dose-dependently decreased serum cytokines in response to administration of IL-1b. Mice pre-treated with R835 demonstrated dose-dependent reductions in MSU crystal-induced serum and peritoneal cytokine levels, as well as neutrophil influx in the peritoneal cavity. Prophylactic and therapeutic treatment with R835 also resulted in significant inhibition of MSU crystal-induced knee edema and pain in a rat model of human gouty arthritis. In the rat model of CIA, R835 blocked both onset and progression of disease, by reducing inflammation, cartilage degeneration and synovial inflammation.

Conclusion:

R835 is a promising clinical candidate for the treatment of a range of cytokine-driven rheumatological diseases. R835 has proven to have desirable pharmacokinetic properties, was well tolerated and suppressed LPS-induced serum cytokines in healthy volunteers in a recent phase 1 study.

References:

[1]Bahia M S, Kaur M, Silakari P, Silakari O. Interleukin-1 receptor associated kinase inhibitors: Potential therapeutic agents for inflammatory- and immune-related disorders. Cellular Signalling 27 (2015) 1039–1055.

Disclosure of Interests:

Chrystelle Lamagna Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Meagan Chan Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Ernest Tai Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Stacey Siu Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Roy Frances Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Sothy Yi Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Chi Young Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Vadim Markovtsov Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Yan Chen Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Lu Chou Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Gary Park Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Esteban Masuda Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Vanessa Taylor Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals

THU0219 FIRST-INHUMAN STUDY OF SAFETY, PHARMACOKINETICS AND PHARMACODYNAMICS OF IRAK1/4 INHIBITOR R835 IN HEALTHY SUBJECTS

Background:

Toll-Like Receptors (TLR) and Interleukin-1 Receptors (IL-1R) play a critical role in the innate immune response as microbial and tissue damage sensors, providing a bridge between the innate and adaptive immunity. Interleukin receptor associated kinases (IRAK) 1 and 4 are serine/threonine kinases that are essential for signaling downstream of most TLRs and IL-1Rs and the resulting production of pro-inflammatory cytokines. Suppression of TLR and IL-1R signaling through inhibition of IRAK1/4 kinases is a promising therapeutic approach for the treatment of inflammatory and autoimmune diseases. We have identified a potent and selective IRAK1/4 inhibitor (R835) that showed dose-dependent inhibition of lipopolysaccharide (LPS, a TLR4 agonist), and IL-1β induced serum cytokines in mice. R835 prevented disease onset and progression in multiple rodent models of inflammatory diseases, including arthritis and lupus models.

Objectives:

The aim of this FIH study was to characterize the safety, pharmacokinetics (PK) and pharmacodynamics (PD) of R835 after single or multiple dose oral administrations.

Methods:

This study was a randomized, placebo-controlled, double-blind Phase 1 study in healthy subjects in three parts: single ascending doses (20 mg-1920 mg, Part A) with food effect in a separate cohort (480 mg), multiple ascending doses (120 mg and 960 mg, BID, Part B) with a caffeine interaction (960 mg cohort), and an intravenous LPS challenge test at 240 mg oral dose of R835 (Part C).

Results:

Single doses of up to 480 mg R835 in organic solution, single doses of up to 1920 mg R835 as capsule, multiple doses of 120 mg R835 Q12H (organic solution), and 960 mg R835 Q12H (capsule) were safe and well tolerated. All R835 related adverse events (AEs) were mild in intensity and reversible, and mostly associated with the higher doses of R835 in the organic solution. The most common AEs were headache and gastrointestinal disturbance. The PK of R835 was linear and dose proportional in exposure over the dose range studied. A nominal level of accumulation in plasma achieved rapidly upon repeated BID administrations with steady-state essentially attained in 2 days. A high-fat meal with the capsule formulation resulted in slow rate of absorption but had no effect on the extent of absorption. There was no effect of R835 on metabolism of caffeine (P450 CYP1A2 prototype substrate). In the LPS challenge test, R835 profoundly inhibited the acute release of cytokines, including TNF-α, IL-6, IL-8, MIP1α and MIP1β, but had no impact on CRP release.

Conclusion:

R835 was well tolerated after single or multiple dose administrations. The most common AEs were headache and gastrointestinal disturbance. For both of the formulations tested, the PK of R835 was linear and exposure was dose proportional with rapid steady-state attainment following BID administration. There was no drug-drug interaction by use of caffeine as the protype substrate. R835 inhibited the LPS induced release of cytokines in the serum, including TNF-α, IL-6, IL-8, MIP1α and MIP1β, mirroring preclinical data in mice. The desirable PK and safety profile combined with proof of mechanism, as demonstrated by inhibition of cytokine release, support progression of R835 into Phase II clinical development as an agent for the treatment of inflammatory and autoimmune diseases.

Disclosure of Interests: :

Lucy Yan Shareholder of: Amgen, Rigel, Employee of: Amgen, Rigel, Sandra Tong Shareholder of: Rigel, Employee of: Rigel, Anthony Absalom: None declared, Izaak den Daas: None declared, Gary Park Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Vanessa Taylor Shareholder of: Rigel Pharmaceuticals, Employee of: Rigel Pharmaceuticals, Donna Chow Shareholder of: Rigel, Employee of: Rigel, Meng Lee Shareholder of: Rigel, Employee of: Rigel, Hanzhe Zheng Shareholder of: Rigel, Employee of: Rigel, Andrew Chow Shareholder of: Rigel, Employee of: Rigel

Comparing enrolees with non-enrolees of cancer-patient navigation at end of life

Background

Cancer-patient navigators who are oncology nurses support and connect patients to resources throughout the cancer care trajectory, including end of life. Although qualitative and cohort studies of navigated patients have been reported, no population-based studies were found. The present population-based study compared demographic, disease, and outcome characteristics for decedents who had been diagnosed with cancer by whether they did or did not see a navigator.

Methods

This retrospective study used patient-based administrative data in Nova Scotia (cancer registry, death certificates, navigation visits) to generate descriptive statistics. The study population included all adults diagnosed with cancer who died during 2011-2014 of a cancer or non-cancer cause of death.

Results

Of the 7694 study decedents, 74.9% had died of cancer. Of those individuals, 40% had seen a navigator at some point in their disease trajectory. The comparable percentage for those who did not die of cancer was 11.9%. Decedents at the oldest ages had the lowest navigation rates. Navigation rates, time from diagnosis to death, and time from last navigation visit to death varied by disease site.

Conclusions

This population-based study of cancer-patient navigation enrolees compared with non-enrolees is the first of its kind. Most findings were consistent with expectations. However, we do not know whether the rates of navigation are consistent with the navigation needs of the population diagnosed with cancer. Because more people are living longer with cancer and because the population is aging, ongoing surveillance of who requires and who is using navigation services is warranted.

Testosterone effects on pain and brain activation patterns

BACKGROUND

This study investigated whether pain and pain-related unpleasantness ratings were altered by blood testosterone levels. We also investigated whether activation of brain regions that represent pain intensity [primary somatosensory cortex (S1)] and pain-related unpleasantness [perigenual ACC (pACC) and orbitofrontal cortex (OFC)] were affected by blood testosterone levels.

METHODS

Twenty-six healthy men were recruited. Blood testosterone levels were measured before fMRI scanning. The participants were classified into two groups (high vs. low testosterone) according to their blood testosterone level (each group n = 13). The middle finger was immersed in a 50°C water bath (50°C, 30 s, five times) to induce identical noxious stimulation in all participants.

RESULTS

The low testosterone group showed statistically significantly higher pain (P = 0.047), unpleasantness (P = 0.047), anxiety (P = 0.015), and fear ratings (P = 0.01) than the high testosterone group. Fear rating increased as pain rating rose and as testosterone level decreased (P < 0.001). When participants received noxious stimulation, the pACC and OFC were more highly activated in the low testosterone group compared to the high testosterone group. Activation of S1, a region related to pain intensity, did not differ between both groups.

CONCLUSION

Compared to the high testosterone group, the low testosterone group had significant activation in the pACC and OFC, regions that represent pain-related unpleasantness, but not in S1 that represents pain intensity, leading to higher pain ratings. These findings emphasize the importance of considering the effects of testosterone levels when treating patients.

Cobll1 is linked to drug resistance and blastic transformation in chronic myeloid leukemia

This corrects the article DOI: 10.1038/leu.2017.107.

Asthma Severity and the Controller Prescription in Children at 12 Tertiary Hospitals

PURPOSE

Guidelines need to be tailored to where they are applied. We aimed to describe the distinctive asthma severity profile and the pattern of controller prescription in Korean children.

METHODS

Twelve pediatric allergists from tertiary medical centers reviewed medical records of all asthmatic children who visited their clinics between September 1 and November 30 of 2013. Controller prescriptions were re-classified into 4 categories, then the prevalence of each asthma severity category and the controller prescription patterns according to asthma severity assessed by a Western (Global Initiative for Asthma, GINA) and an Asia-Pacific (Japanese Pediatric GuideLine, JPGL) guideline were evaluated.

RESULTS

A total of 840 cases were reviewed. Both GINA and JPGL revealed that 328 (39.0%) and 249 (29.6%) subjects had intermittent asthma whereas 24 (2.9%) and 21 (2.5%) subjects had severe persistent asthma, respectively. Although higher category controllers tended to be prescribed to those who had more severe asthma, there was much overlap in categories of prescribed controllers between groups with regard to asthma severities. Leukotriene receptor antagonists (LTRA) was the most frequently prescribed as a single controller (40%) or as an add-on medication (19%) in the group of asthmatic children <6 years.

CONCLUSIONS

Korean children have distinctive patterns of asthma severity and management strategies with a lower prevalence of severe asthma and a preference toward LTRA rather than low dose inhaled corticosteroids (ICS) alone or add-on long-acting beta-agonist (LABA) in the group of <6 year-old asthmatics that has not been predicted in Western countries. Thus, strategies tailored to regional situations need to be developed and recommended.

Extracellular ATP Induces Calcium Signaling in Odontoblasts

Odontoblasts form dentin at the outermost surface of tooth pulp. An increasing level of evidence in recent years, along with their locational advantage, implicates odontoblasts as a secondary role as sensory or immune cells. Extracellular adenosine triphosphate (ATP) is a well-characterized signaling molecule in the neuronal and immune systems, and its potential involvement in interodontoblast communications was recently demonstrated. In an effort to elaborate the ATP-mediated signaling pathway in odontoblasts, the current study performed single-cell reverse transcription polymerase chain reaction (RT-PCR) and immunofluorescent detection to investigate the expression of ATP receptors related to calcium signal in odontoblasts from incisal teeth of 8- to 10-wk-old rats, and demonstrated an in vitro response to ATP application via calcium imaging experiments. While whole tissue RT-PCR analysis detected P2Y₂, P2Y₄, and all 7 subtypes (P2X₁ to P2X₇) in tooth pulp, single-cell RT-PCR analysis of acutely isolated rat odontoblasts revealed P2Y₂, P2Y₄, P2X₂, P2X₄, P2X₆, and P2X₇ expression in only a subset (23% to 47%) of cells tested, with no evidence for P2X₁, P2X₃, and P2X₅ expression. An increase of intracellular Ca²⁺ concentration in response to 100μM ATP, which was repeated after pretreatment of thapsigargin or under the Ca²⁺-free condition, suggested function of both ionotropic and metabotropic ATP receptors in odontoblasts. The enhancement of ATP-induced calcium response by ivermectin and inhibition by 5-(3-bromophenyl)-1,3-dihydro-2H-benzofuro[3,2-e]-1,4-diazepin-2-one (5-BDBD) confirmed a functional P2X₄ subtype in odontoblasts. Positive calcium response to 2',3'-O-(benzoyl-4-benzoyl)-ATP (BzATP) and negative response to α,β-methylene ATP suggested P2X₂, P2X₄, and P2X₇ as functional subunits in rat odontoblasts. Single-cell RT-PCR analysis of the cells with confirmed calcium response and immunofluorescent detection further corroborated the expression of P2X₄ and P2X₇ in odontoblasts. Overall, this study demonstrated heterogeneous expression of calcium-related ATP receptor subtypes in subsets of individual odontoblasts, suggesting extracellular ATP as a potential signal mediator for odontoblastic functions.

Protein stability changes of the novel p.Arg180Cys mutant A glycosyltransferase resulted in a weak A phenotype

A novel A subgroup allele (c.538C>T p.Arg180Cys) showing weak A phenotype was found in a 30-year-old Korean woman with ABO discrepancy. Using 3D structural analysis, protein stability prediction and flow cytometric analysis of ABO antigen expression on HeLa cells transfected with plasmids containing the p.Arg180Cys mutant, we found that the Arg180 residue in the loop region of the A glycosyltransferases (GTA) structure plays significant role in stabilizing its closed conformation, which is required for substrate binding and catalysis study.

Non-invasive assessment of cutaneous wound healing using fluorescent imaging

BACKGROUND/PURPOSE

Optical imaging is a very important technique in the biomedical sciences. The purpose of this study was to develop an in vivo optical system for fluorescent imaging and molecular imaging applications using quantum dots (QDs).

METHODS

The in vivo optical system was composed of modular parts, including a light source, light guide, excitation filter wheel, excitation filters, emission filter wheel, emission filters, liquid crystal tunable filter (LCTF), macro lens, dark chamber, and a cooled charged-coupled device (CCD) camera for recording images. Filters were selected based on the excitation and absorption spectra of QDs to allow spectral separation and optimization of the acquired image. In contrast with conventional systems, our system allows selection of the emission bandwidth.

RESULTS

The system was tested in an in vivo study using a wound-healing model in nude mice. The healing process was examined after injection of fibroblasts and keratinocytes labeled with two different sets of QDs. The different QD probes were readily detected and distinguished using our system.

CONCLUSION

An in vivo optical system is a very useful tool for the detection of genes, proteins, and small-molecule drugs inside living animals, and this imaging modality can also be adopted for real-time visualization of cancer cell metastasis in live animals.