The State of the Art in Machining Additively Manufactured Titanium Alloy Ti-6Al-4V.

Titanium alloys are extensively used in various industries due to their excellent corrosion resistance and outstanding mechanical properties. However, titanium alloys are difficult to machine due to their low thermal conductivity and high chemical reactivity with tool materials. In recent years, there has been increasing interest in the use of titanium components produced by additive manufacturing (AM) for a range of high-value applications in aerospace, biomedical, and automotive industries. The machining of additively manufactured titanium alloys presents additional machining challenges as the alloys exhibit unique properties compared to their wrought counterparts, including increased anisotropy, strength, and hardness. The associated higher cutting forces, higher temperatures, accelerated tool wear, and decreased machinability lead to an expensive and unsustainable machining process. The challenges in machining additively manufactured titanium alloys are not comprehensively documented in the literature, and this paper aims to address this limitation. A review is presented on the machining characteristics of titanium alloys produced by different AM techniques, focusing on the effects of anisotropy, porosity, and post-processing treatment of additively manufactured Ti-6Al-4V, the most commonly used AM titanium alloy. The mechanisms resulting in different machining performance and quality are analysed, including the influence of a hybrid manufacturing approach combining AM with conventional methods. Based on the review of the latest developments, a future outlook for machining additively manufactured titanium alloys is presented.

Diurnal variation in DLCO and non-standardized study procedures may cause a false positive safety signal in clinical trials.

Diffusing capacity for carbon monoxide (DLCO) was measured in a phase I single ascending dose study after inhalation of AZD8154 or placebo in healthy participants at baseline (DLCOBaseline) and follow-up (DLCOFollow-up) 6 days after dosing. Initially, DLCOFollow-up timepoint was 2 h earlier than the DLCOBaseline timepoint and clinically significant decreases in DLCOFollow-up (absolute change up to 19% from baseline and DLCO%predicted values less than 70) were observed then. The observed reduction in DLCOFollow-up was confirmed as a false positive finding after alignment of DLCO timings. As a consequence, when DLCO is used in clinical studies, measurements should be strictly standardized in relation to time of the day.

Pharmacokinetics, pharmacodynamics and safety of the inverse retinoic acid-related orphan receptor γ agonist AZD0284.

AIMS: Retinoic acid-related orphan receptor γ (RORγ), a master regulator of T-helper 17 (Th17) cell function and differentiation, is an attractive target for treatment of Th17-driven diseases. This first-in-human study aimed to investigate the pharmacokinetics, pharmacodynamics, safety and tolerability of the inverse RORγ agonist AZD0284. METHODS: We conducted a phase I, randomized, single-blind, placebo-controlled, two-part, first-in-human study with healthy subjects receiving single (4-238 mg) or multiple (12-100 mg) oral doses of AZD0284 or placebo after overnight fasting. Subjects in the one single dose cohort additionally received a single dose of AZD0284 after a high-calorie meal. AZD0284 plasma concentrations, as well as inhibition of ex vivo-stimulated interleukin (IL)-17A release in whole blood, were frequently measured after both single and multiple dosing. RESULTS: Eighty-three men participated in the study. AZD0284 was absorbed rapidly into plasma after oral dosing and exhibited a terminal half-life of 13-16 hours. Both the area under the concentration-time curve (AUC) and maximum concentration (Cmax ) increased subproportionally with increasing dose (95% confidence intervals of slope parameter were 0.71-0.84 and 0.72-0.88 for AUC and Cmax , respectively). Food intake delayed the absorption of AZD0284 but did not affect the overall exposure or half-life. AZD0284 showed dose-dependent reduction of ex vivo-stimulated IL-17A release after both single and multiple doses. No significant safety concerns were identified in the study. CONCLUSIONS: AZD0284 was well tolerated, rapidly and dose-dependently absorbed, and reduced stimulated IL-17A release after single and multiple dosing. The results of this study support further clinical development of AZD0284.

Two subgroups in systemic lupus erythematosus with features of antiphospholipid or Sjögren's syndrome differ in molecular signatures and treatment perspectives.

BACKGROUND: Previous studies and own clinical observations of patients with systemic lupus erythematosus (SLE) suggest that SLE harbors distinct immunophenotypes. This heterogeneity might result in differences in response to treatment in different subgroups and obstruct clinical trials. Our aim was to understand how SLE subgroups may differ regarding underlying pathophysiology and characteristic biomarkers. METHODS: In a cross-sectional study, including 378 well-characterized SLE patients and 316 individually matched population controls, we defined subgroups based on the patients' autoantibody profile at inclusion. We selected a core of an antiphospholipid syndrome-like SLE (aPL+ group; positive in the lupus anticoagulant (LA) test and negative for all three of SSA (Ro52 and Ro60) and SSB antibodies) and a Sjögren's syndrome-like SLE (SSA/SSB+ group; positive for all three of SSA (Ro52 and Ro60) and SSB antibodies but negative in the LA test). We applied affinity-based proteomics, targeting 281 proteins, together with well-established clinical biomarkers and complementary immunoassays to explore the difference between the two predefined SLE subgroups. RESULTS: The aPL+ group comprised 66 and the SSA/SSB+ group 63 patients. The protein with the highest prediction power (receiver operating characteristic (ROC) area under the curve = 0.89) for separating the aPL+ and SSA/SSB+ SLE subgroups was integrin beta-1 (ITGB1), with higher levels present in the SSA/SSB+ subgroup. Proteins with the lowest p values comparing the two SLE subgroups were ITGB1, SLC13A3, and CERS5. These three proteins, rheumatoid factor, and immunoglobulin G (IgG) were all increased in the SSA/SSB+ subgroup. This subgroup was also characterized by a possible activation of the interferon system as measured by high KRT7, TYK2, and ETV7 in plasma. In the aPL+ subgroup, complement activation was more pronounced together with several biomarkers associated with systemic inflammation (fibrinogen, α-1 antitrypsin, neutrophils, and triglycerides). CONCLUSIONS: Our observations indicate underlying pathogenic differences between the SSA/SSB+ and the aPL+ SLE subgroups, suggesting that the SSA/SSB+ subgroup may benefit from IFN-blocking therapies while the aPL+ subgroup is more likely to have an effect from drugs targeting the complement system. Stratifying SLE patients based on an autoantibody profile could be a way forward to understand underlying pathophysiology and to improve selection of patients for clinical trials of targeted treatments.

Cytokine production by activated plasmacytoid dendritic cells and natural killer cells is suppressed by an IRAK4 inhibitor.

BACKGROUND: In systemic lupus erythematosus (SLE), immune complexes (ICs) containing self-derived nucleic acids trigger the synthesis of proinflammatory cytokines by immune cells. We asked how an interleukin (IL)-1 receptor-associated kinase 4 small molecule inhibitor (IRAK4i) affects RNA-IC-induced cytokine production compared with hydroxychloroquine (HCQ). METHODS: Plasmacytoid dendritic cells (pDCs) and natural killer (NK) cells were isolated from peripheral blood mononuclear cells (PBMCs) of healthy individuals. PBMCs from SLE patients and healthy individuals were depleted of monocytes. Cells were stimulated with RNA-containing IC (RNA-IC) in the presence or absence of IRAK4i I92 or HCQ, and cytokines were measured by immunoassay or flow cytometry. Transcriptome sequencing was performed on RNA-IC-stimulated pDCs from healthy individuals to assess the effect of IRAK4i and HCQ. RESULTS: In healthy individuals, RNA-IC induced interferon (IFN)-α, tumor necrosis factor (TNF)-α, IL-6, IL-8, IFN-γ, macrophage inflammatory protein (MIP)1-α, and MIP1-ß production in pDC and NK cell cocultures. IFN-α production was selective for pDCs, whereas both pDCs and NK cells produced TNF-α. IRAK4i reduced the pDC and NK cell-derived cytokine production by 74-95%. HCQ interfered with cytokine production in pDCs but not in NK cells. In monocyte-depleted PBMCs, IRAK4i blocked cytokine production more efficiently than HCQ. Following RNA-IC activation of pDCs, 975 differentially expressed genes were observed (false discovery rate (FDR) < 0.05), with many connected to cytokine pathways, cell regulation, and apoptosis. IRAK4i altered the expression of a larger number of RNA-IC-induced genes than did HCQ (492 versus 65 genes). CONCLUSIONS: The IRAK4i I92 exhibits a broader inhibitory effect than HCQ on proinflammatory pathways triggered by RNA-IC, suggesting IRAK4 inhibition as a therapeutic option in SLE.

Dipeptidyl Peptidase 1 Inhibitor AZD7986 Induces a Sustained, Exposure-Dependent Reduction in Neutrophil Elastase Activity in Healthy Subjects.

Neutrophil serine proteases (NSPs), such as neutrophil elastase (NE), are activated by dipeptidyl peptidase 1 (DPP1) during neutrophil maturation. High NSP levels can be detrimental, particularly in lung tissue, and inhibition of NSPs is therefore an interesting therapeutic opportunity in multiple lung diseases, including chronic obstructive pulmonary disease (COPD) and bronchiectasis. We conducted a randomized, placebo-controlled, first-in-human study to assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of single and multiple oral doses of the DPP1 inhibitor AZD7986 in healthy subjects. Pharmacokinetic and pharmacodynamic data were analyzed using nonlinear mixed effects modeling and showed that AZD7986 inhibits whole blood NE activity in an exposure-dependent, indirect manner-consistent with in vitro and preclinical predictions. Several dose-dependent, possibly DPP1-related, nonserious skin findings were observed, but these were not considered to prevent further clinical development. Overall, the study results provided confidence to progress AZD7986 to phase II and supported selection of a clinically relevant dose.

The STAT4 SLE risk allele rs7574865[T] is associated with increased IL-12-induced IFN-γ production in T cells from patients with SLE.

OBJECTIVES: Genetic variants in the transcription factor STAT4 are associated with increased susceptibility to systemic lupus erythematosus (SLE) and a more severe disease phenotype. This study aimed to clarify how the SLE-associated intronic STAT4 risk allele rs7574865[T] affects the function of immune cells in SLE. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from 52 genotyped patients with SLE. Phosphorylation of STAT4 (pSTAT4) and STAT1 (pSTAT1) in response to interferon (IFN)-α, IFN-γ or interleukin (IL)-12, total levels of STAT4, STAT1 and T-bet, and frequency of IFN-γ+ cells on IL-12 stimulation were determined by flow cytometry in subsets of immune cells before and after preactivation of cells with phytohaemagglutinin (PHA) and IL-2. Cellular responses and phenotypes were correlated to STAT4 risk allele carriership. Janus kinase inhibitors (JAKi) selective for TYK2 (TYK2i) or JAK2 (JAK2i) were evaluated for inhibition of IL-12 or IFN-γ-induced activation of SLE PBMCs. RESULTS: In resting PBMCs, the STAT4 risk allele was neither associated with total levels of STAT4 or STAT1, nor cytokine-induced pSTAT4 or pSTAT1. Following PHA/IL-2 activation, CD8+ T cells from STAT4 risk allele carriers displayed increased levels of STAT4 resulting in increased pSTAT4 in response to IL-12 and IFN-α, and an augmented IL-12-induced IFN-γ production in CD8+ and CD4+ T cells. The TYK2i and the JAK2i efficiently blocked IL-12 and IFN-γ-induced activation of PBMCs from STAT4 risk patients, respectively. CONCLUSIONS: T cells from patients with SLE carrying the STAT4 risk allele rs7574865[T] display an augmented response to IL-12 and IFN-α. This subset of patients may benefit from JAKi treatment.

Simple and robust two-step ex vivo whole blood stimulation assay suitable for investigating IL-17 pathway in a clinical laboratory setting.

We describe a simple and robust tube-based ex vivo whole blood stimulation procedure suitable for use in clinical laboratories by multiple operators on repeated occasions to study cytokine production in phase 1 human trials of investigational medicines, developed by the authors specifically to study IL-17A expression in man. The stimulation procedure is further proposed as a useful tool for biomarker assay development and validation, for example to prepare quality control samples without reliance on recombinant materials for spiking.

Specific accumulation of orally administered redox nanotherapeutics in the inflamed colon reducing inflammation with dose-response efficacy.

Although current medications for ulcerative colitis (UC) are effective to some extent, there are still some limitation of their use due to the non-specific distribution, drug metabolism in the gastrointestinal tract, and severe adverse effects. In our previous studies, we developed oral redox nanoparticles (RNP(O)) that specifically accumulated and scavenged overproduced reactive oxygen species (ROS) in an inflamed colon. However, the mechanism leading to specific accumulation of RNP(O) in an inflamed colon is still unclear. In this study, we investigated the cellular uptake of RNP(O) into ROS-treated epithelial colonic cells in vitro, and compared to the untreated cells, found a significantly increased uptake in ROS-treated cells. In vivo, we discovered that orally administered RNP(O) were not internalized into the cells of a normal colon. A significant amount of disintegrated RNP(O) was detected in the cells of an inflamed colon of dextran sodium sulfate (DSS)-induced colitis mice, resulting in scavenging of ROS and suppression of inflammation with low adverse effects. Furthermore, we confirmed a significant reduction of disease activity and a robust dose response efficacy following RNP(O) treatment in acute DSS-induced colitis mice, outperforming the positive control 5-aminosalicylic acid. Oral administration of RNP(O) is a promising approach to develop a new therapy for UC disease.

Effects of an oral MMP-9 and -12 inhibitor, AZD1236, on biomarkers in moderate/severe COPD: a randomised controlled trial.

BACKGROUND: There is a pressing need for new forms of treatment for COPD. Based on the known pathophysiology of COPD, inhibition of matrix metalloproteinases is a theoretically promising approach. This Phase IIa study evaluated the effects of AZD1236, a selective MMP-9 and MMP-12 inhibitor, on the biomarkers of inflammation and emphysematous lung tissue degradation in patients with moderate-to-severe COPD. METHODS: This was a multinational, randomized, double-blind, placebo-controlled signal-searching study conducted in men and women aged ≥40 years with stable moderate-to-severe COPD. After a 2-6-week period to eliminate any remaining effects of previous medication, 55 patients received oral AZD1236 75 mg or matching placebo twice daily for 6 weeks. Differential cell count and TNF-α levels in induced sputum and 24-h urinary desmosine excretion were the main study variables, but a range of exploratory biomarkers was also assessed in induced sputum, blood and urine. Secondary variables included lung function and patient-recorded Clinical COPD Questionnaire (CCQ) responses and diary records of symptoms, adverse events, use of rescue medication and AZD1236 plasma concentrations. RESULTS: The majority of variables showed little change compared to placebo although there was a possible, but not statistically significant reduction in urinary desmosine excretion and reductions in the number and percentage of lymphocytes in sputum and blood with AZD1236. No effect was seen on clinical parameters after 6 weeks of treatment. The proportion of patients experiencing adverse events was similar in both treatment groups. CONCLUSIONS: AZD1236 dosed orally at 75 mg twice daily was generally well tolerated over 6 weeks in patients with moderate-to-severe COPD. No clinical efficacy of AZD1236 was demonstrated in this short-term signal-searching study, although possible evidence of an impact on desmosine may suggest the potential value of selective inhibitors of MMPs in the treatment of COPD in longer term trials.

Pathogenic autoreactive B cells are not negatively selected toward matrix protein collagen II.

We have addressed the importance of B cell tolerance to collagen type II, a matrix protein, which is a target in rheumatoid arthritis (RA) and its mouse models. We generated a germline-encoded anti-collagen type II (CII) IgH replacement anti-C1 B cell mouse strain (ACB) to investigate how B cell tolerance to CII, a matrix protein, is subverted and to further understand pathogenesis of RA. Phenotypic analysis revealed that CII-specific B cells were surprisingly neither deleted nor anergized. Instead, they were readily detected in all lymphoid organs. Spontaneously produced autoantibodies could bind directly to cartilage surface without detectable pathology. However, exaggerated arthritis was seen after injection of anti-CII Abs specific for other epitopes. In addition, Abs from CII-specific hybridomas generated from ACB mice induced arthritis. Interestingly, IgH/L chain sequence data in B cell hybridomas revealed a lack of somatic mutations in autoreactive B cells. The ACB model provides the first possibility, to our knowledge, to study B cell tolerance to a matrix protein, and the observations made in the study could not be predicted from previous models. B cell-reactive epitopes on CII are largely shared between human RA and rodent CII-induced arthritis; this study, therefore, has important implications for further understanding of pathological processes in autoimmune diseases like RA.

Safety and tolerability of an oral MMP-9 and -12 inhibitor, AZD1236, in patients with moderate-to-severe COPD: a randomised controlled 6-week trial.

BACKGROUND: Matrix metalloproteinases (MMPs) have been implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD). This phase IIa study investigated the safety and tolerability of oral AZD1236, an MMP-9 and MMP-12 inhibitor, in patients with COPD. Efficacy analyses were included on an exploratory basis. METHODS: This was a multinational, randomised, double-blind, parallel-group study conducted in 74 men and women aged ≥40 years with stable moderate-to-severe COPD. After a 2-week run-in period, patients received oral AZD1236 75 mg, or matching placebo, twice daily for 6 weeks (on top of background medication with short-acting bronchodilators and/or inhaled corticosteroids, if applicable). In addition to safety and tolerability endpoints (AEs, vital signs and laboratory assessments) efficacy was assessed as a secondary objective (spirometry, 6MWT, BODE index and biomarkers in blood and urine. Clinical COPD Questionnaire (CCQ), peak expiratory flow (PEF) and daily diary cards of symptom severity were completed by the patients. RESULTS: The incidence of adverse events (AEs) was similar in AZD1236 and placebo recipients; 28 in 13 patients (37%) and 21 in 17 patients (44%), respectively; the difference in actual number reported accounted for primarily by mild AEs in the AZD1236 group. The most commonly experienced AEs in both groups were COPD exacerbations, headache and viral infections. One patient in the AZD1236 group experienced a serious AE of interstitial nephritis (comprising of acute renal failure, rash, fever and blood eosinophilia) considered to be related to treatment. After 6 weeks, AZD1236 had demonstrated no significant effect on lung function, 6MWT, BODE index or biomarkers compared with placebo. No meaningful differences were observed in patient-reported CCQ score, PEF, COPD symptoms or use of rescue medication. CONCLUSIONS: For most of these COPD patients, with the particular exception of one who experienced a serious AE, AZD1236 at 75 mg twice daily was generally well tolerated and had an acceptable safety profile. Therapeutic efficacy could not be demonstrated, possibly due to the stable disease and background medications of the patients enrolled in this small, short-term study.

Cartilage destruction in collagen induced arthritis assessed with a new biochemical marker for collagen type II C-telopeptide fragments.

OBJECTIVE: To assess the ability of a marker of collagen type II degradation (CTX-II) to quantify cartilage turnover in vitro in cartilage explants and in vivo in rats with collagen induced arthritis (CIA). METHODS: Bovine articular cartilage explants were cultured in the presence of interleukin 1a, oncostatin M, and plasminogen to induce cartilage degradation. CTX-II, CTX-I (C-telopeptide fragment of collagen type I), glycosaminoglycan, and hydroxyproline contents in culture supernatants were measured. CIA was induced in 12-week-old female Lewis rats by immunization with bovine type II collagen. The incidence and severity of arthritis were monitored by measuring paw swelling, and urinary levels of CTX-II and CTX-I were determined. The knee joints of rats were histopathologically examined after sacrifice. Results. CTX-II but not CTX-I levels correlated well with collagen degradation in bovine articular cartilage in vitro quantified by hydroxyproline release. Urinary CTX-II levels as well as paw volume of CIA rats were significantly higher than normal rats on Days 21, 28, and 42 and were apparently correlated with cartilage destruction, assessed histopathologically. Urinary CTX-I level began to increase on Day 21, but only on Day 42 was it significantly different between CIA and normal rats. The elevation in CTX-I level appeared to occur later than that of CTX-II, in accord with the more delayed onset of bone erosion in the CIA model of rheumatoid arthritis. CONCLUSION: Urinary CTX-II may be a useful marker for evaluation of dynamics of cartilage destruction in CIA rats.

Ovariectomized rats as a model of postmenopausal osteoarthritis: validation and application.

We aimed to assess the effect of ovariectomy on cartilage turnover and degradation, to evaluate whether ovariectomized (OVX) rats could form an experimental model of postmenopausal osteoarthritis. The effect of ovariectomy on cartilage was studied using two cohorts of female Sprague-Dawley rats, aged 5 and 7 months. In a third cohort, the effect of exogenous estrogen and a selective estrogen receptor modulator was analyzed. Knee joints were assessed by histological analysis of the articular cartilage after 9 weeks. Cartilage turnover was measured in urine by an immunoassay specific for collagen type II degradation products (CTX-II), and bone resorption was quantified in serum using an assay for bone collagen type I fragments (CTX-I). Surface erosion in the cartilage of the knee was more severe in OVX rats than in sham-operated animals, particularly in the 7-month-old cohort (P = 0.008). Ovariectomy also significant increased CTX-I and CTX-II. Both the absolute levels of CTX-II and the relative changes from baseline seen at week 4 correlated strongly with the severity of cartilage surface erosion at termination (r = 0.74, P < 0.01). Both estrogen and the selective estrogen receptor modulator inhibited the ovariectomy-induced acceleration of cartilage and bone turnover and significantly suppressed cartilage degradation and erosion seen in vehicle-treated OVX rats. The study indicates that estrogen deficiency accelerates cartilage turnover and increases cartilage surface erosion. OVX rats provide a useful experimental model for the evaluation of the chondroprotective effects of estrogens and estrogen-like substances and the model may be an in vivo representation of osteoarthritis in postmenopausal women.