IL-7 coordinates proliferation, differentiation and Tcra recombination during thymocyte ß-selection.

Signaling via the pre-T cell antigen receptor (pre-TCR) and the receptor Notch1 induces transient self-renewal (ß-selection) of TCRß(+) CD4(-)CD8(-) double-negative stage 3 (DN3) and DN4 progenitor cells that differentiate into CD4(+)CD8(+) double-positive (DP) thymocytes, which then rearrange the locus encoding the TCR α-chain (Tcra). Interleukin 7 (IL-7) promotes the survival of TCRß(-) DN thymocytes by inducing expression of the pro-survival molecule Bcl-2, but the functions of IL-7 during ß-selection have remained unclear. Here we found that IL-7 signaled TCRß(+) DN3 and DN4 thymocytes to upregulate genes encoding molecules involved in cell growth and repressed the gene encoding the transcriptional repressor Bcl-6. Accordingly, IL-7-deficient DN4 cells lacked trophic receptors and did not proliferate but rearranged Tcra prematurely and differentiated rapidly. Deletion of Bcl6 partially restored the self-renewal of DN4 cells in the absence of IL-7, but overexpression of BCL2 did not. Thus, IL-7 critically acts cooperatively with signaling via the pre-TCR and Notch1 to coordinate proliferation, differentiation and Tcra recombination during ß-selection.

A molecular cell atlas of the human lung from single-cell RNA sequencing.

Although single-cell RNA sequencing studies have begun to provide compendia of cell expression profiles1-9, it has been difficult to systematically identify and localize all molecular cell types in individual organs to create a full molecular cell atlas. Here, using droplet- and plate-based single-cell RNA sequencing of approximately 75,000 human cells across all lung tissue compartments and circulating blood, combined with a multi-pronged cell annotation approach, we create an extensive cell atlas of the human lung. We define the gene expression profiles and anatomical locations of 58 cell populations in the human lung, including 41 out of 45 previously known cell types and 14 previously unknown ones. This comprehensive molecular atlas identifies the biochemical functions of lung cells and the transcription factors and markers for making and monitoring them; defines the cell targets of circulating hormones and predicts local signalling interactions and immune cell homing; and identifies cell types that are directly affected by lung disease genes and respiratory viruses. By comparing human and mouse data, we identified 17 molecular cell types that have been gained or lost during lung evolution and others with substantially altered expression profiles, revealing extensive plasticity of cell types and cell-type-specific gene expression during organ evolution including expression switches between cell types. This atlas provides the molecular foundation for investigating how lung cell identities, functions and interactions are achieved in development and tissue engineering and altered in disease and evolution.

Adoption of Multi-society Guidelines Facilitates Value-Based Reduction in Screening and Surveillance Colonoscopy Volume During COVID-19 Pandemic.

BACKGROUND: COVID-19 has caused a backlog of endoscopic procedures; colonoscopy must now be prioritized to those who would benefit most. We determined the proportion of screening and surveillance colonoscopies appropriate for rescheduling to a future year through strict adoption of US Multi-Society Task Force (USMSTF) guidelines. METHODS: We conducted a single-center observational study of patients scheduled for "open-access colonoscopy"-ordered by a primary care provider without being seen in gastroenterology clinic-over a 6-week period during the COVID-19 pandemic. Each chart was reviewed to appropriately assign a surveillance year per USMSTF guidelines including demographics, colonoscopy history and family history. When guidelines recommended a range of colonoscopy intervals, both a "conservative" and "liberal" guideline adherence were assessed. RESULTS: We delayed 769 "open-access" screening or surveillance colonoscopies due to COVID-19. Between 14.8% (conservative) and 20.7% (liberal), colonoscopies were appropriate for rescheduling to a future year. Conversely, 415 (54.0%) patients were overdue for colonoscopy. Family history of CRC was associated with being scheduled too early for both screening (OR 3.9; CI 1.9-8.2) and surveillance colonoscopy (OR 2.6, CI 1.0-6.5). The most common reasons a colonoscopy was inappropriately scheduled this year were failure to use new surveillance colonoscopy intervals (28.9%), incorrectly applied family history guidelines (27.2%) and recommending early surveillance colonoscopy after recent normal colonoscopy (19.3%). CONCLUSION: Up to one-fifth of patients scheduled for "open-access" colonoscopy can be rescheduled into a future year based on USMSTF guidelines. Rigorously applying guidelines could judiciously allocate colonoscopy resources as we recover from the COVID-19 pandemic.

Drug responses are conserved across patient-derived xenograft models of melanoma leading to identification of novel drug combination therapies.

BACKGROUND: Patient-derived xenograft (PDX) mouse tumour models can predict response to therapy in patients. Predictions made from PDX cultures (PDXC) would allow for more rapid and comprehensive evaluation of potential treatment options for patients, including drug combinations. METHODS: We developed a PDX library of BRAF-mutant metastatic melanoma, and a high-throughput drug-screening (HTDS) platform utilising clinically relevant drug exposures. We then evaluated 34 antitumor agents across eight melanoma PDXCs, compared drug response to BRAF and MEK inhibitors alone or in combination with PDXC and the corresponding PDX, and investigated novel drug combinations targeting BRAF inhibitor-resistant melanoma. RESULTS: The concordance of cancer-driving mutations across patient, matched PDX and subsequent PDX generations increases as variant allele frequency (VAF) increases. There was a high correlation in the magnitude of response to BRAF and MEK inhibitors between PDXCs and corresponding PDXs. PDXCs and corresponding PDXs from metastatic melanoma patients that progressed on standard-of-care therapy demonstrated similar resistance patterns to BRAF and MEK inhibitor therapy. Importantly, HTDS identified novel drug combinations to target BRAF-resistant melanoma. CONCLUSIONS: The biological consistency observed between PDXCs and PDXs suggests that PDXCs may allow for a rapid and comprehensive identification of treatments for aggressive cancers, including combination therapies.

Ibrutinib for Chronic Graft-versus-Host Disease After Failure of Prior Therapy: 1-Year Update of a Phase 1b/2 Study.

Chronic graft-versus-host disease (cGVHD) is a life-threatening complication of allogeneic stem cell transplantation. In a Phase 1b/2, open-label study (PCYC-1129; ClinicalTrials.gov identifier NCT02195869) involving 42 patients with active cGVHD who were steroid-dependent or -refractory, the activity and safety of ibrutinib, a once-daily inhibitor of Bruton's tyrosine kinase, was demonstrated. Here we report extended follow-up for patients in this study. After a median follow-up of 26 months (range, .53 to 36.7 months), best overall response rate in the all treated population was 69% (29 of 42), with 13 patients (31%) achieving a complete response and 16 patients (38%) achieving a partial response. Sustained responses of ≥20, ≥32, and ≥44 weeks were seen in 20 (69%), 18 (62%), and 16 (55%) of the 29 responders, respectively. Of 26 patients with ≥2 involved organs, 19 (73%) showed responses in ≥2 organs. Six of 10 patients (60%) with ≥3 involved organs showed responses in ≥3 organs. Eleven of 18 patients (61%) who had sclerosis at baseline showed a sclerotic response (39% with complete response, 22% with partial response). Twenty-seven of 42 patients (64%) reached a corticosteroid dose of <.15 mg/kg/day during the study; 8 discontinued corticosteroid treatment and remained off corticosteroid at study closure. Safety findings for this updated analysis were consistent with the safety profile seen at the time of the original analysis. Common grade ≥3 adverse events (AEs) were pneumonia (n = 6), fatigue (n = 5), and diarrhea (n = 4). The onset of new grade ≥3 AEs decreased from 71% in the first year of treatment to 25% in the second year (n = 12). AEs leading to discontinuation occurred in 18 patients (43%). At a median follow-up of >2 years, ibrutinib continued to produce durable responses in patients with cGVHD who had failed previous systemic therapy. In this pretreated, high-risk population, clinically meaningful benefit and an acceptable safety profile were observed with additional follow-up for ibrutinib. These results demonstrate a substantial advance in the therapeutic management of patients with cGVHD.

Incidence of and risk factors for major haemorrhage in patients treated with ibrutinib: An integrated analysis.

Ibrutinib, a Bruton tyrosine kinase inhibitor, is approved for treatment of various B-cell malignancies. In ibrutinib clinical studies, low-grade haemorrhage was common, whereas major haemorrhage (MH) was infrequent. We analysed the incidence of and risk factors for MH from 15 ibrutinib clinical studies (N = 1768), including 4 randomised controlled trials (RCTs). Rates of any-grade bleeding were similar for single-agent ibrutinib and ibrutinib combinations (39% and 40%). Low-grade bleeding was more common in ibrutinib-treated than comparator-treated patients (35% and 15%), and early low-grade bleeding was not associated with MH. The proportion of MH in RCTs was higher with ibrutinib than comparators (4.4% vs. 2.8%), but after adjusting for longer exposure with ibrutinib (median 13 months vs. 6 months), the incidence of MH was similar (3.2 vs. 3.1 per 1000 person-months). MH led to treatment discontinuation in 1% of all ibrutinib-treated patients. Use of anticoagulants and/or antiplatelets (AC/AP) during the study was common (~50% of patients) and had an increased exposure-adjusted relative risk for MH in both the total ibrutinib-treated population (1.9; 95% confidence interval, 1.2-3.0) and RCT comparator-treated patients (2.4; 95% confidence interval, 1.0-5.6), indicating that ibrutinib may not alter the effect of AC/AP on the risk of MH in B-cell malignancies.

Ibrutinib for chronic graft-versus-host disease after failure of prior therapy.

Chronic graft-versus-host disease (cGVHD) is a serious complication of allogeneic stem cell transplantation with few effective options available after failure of corticosteroids. B and T cells play a role in the pathophysiology of cGVHD. Ibrutinib inhibits Bruton tyrosine kinase in B cells and interleukin-2-inducible T-cell kinase in T cells. In preclinical models, ibrutinib reduced severity of cGVHD. This multicenter, open-label study evaluated the safety and efficacy of ibrutinib in patients with active cGVHD with inadequate response to corticosteroid-containing therapies. Forty-two patients who had failed 1 to 3 prior treatments received ibrutinib (420 mg) daily until cGVHD progression. The primary efficacy end point was cGVHD response based on 2005 National Institutes of Health criteria. At a median follow-up of 13.9 months, best overall response was 67%; 71% of responders showed a sustained response for ≥20 weeks. Responses were observed across involved organs evaluated. Most patients with multiple cGVHD organ involvement had a multiorgan response. Median corticosteroid dose in responders decreased from 0.29 mg/kg per day at baseline to 0.12 mg/kg per day at week 49; 5 responders discontinued corticosteroids. The most common adverse events were fatigue, diarrhea, muscle spasms, nausea, and bruising. Plasma levels of soluble factors associated with inflammation, fibrosis, and cGVHD significantly decreased over time with ibrutinib. Ibrutinib resulted in clinically meaningful responses with acceptable safety in patients with ≥1 prior treatments for cGVHD. Based on these results, ibrutinib was approved in the United States for treatment of adult patients with cGVHD after failure of 1 or more lines of systemic therapy. This trial was registered at www.clinicaltrials.gov as #NCT02195869.

Outcomes with ibrutinib by line of therapy and post-ibrutinib discontinuation in patients with chronic lymphocytic leukemia: Phase 3 analysis.

The efficacy of ibrutinib has been demonstrated in patients with chronic lymphocytic leukemia (CLL), including as first-line therapy. However, outcomes after ibrutinib discontinuation have previously been limited to higher-risk populations with relapsed/refractory (R/R) disease. The objective of this study was to evaluate outcomes of ibrutinib-treated patients based on prior lines of therapy, including after ibrutinib discontinuation. Data were analyzed from two multicenter phase 3 studies of single-agent ibrutinib: RESONATE (PCYC-1112) in patients with R/R CLL and RESONATE-2 (PCYC-1115) in patients with treatment-naive (TN) CLL without del(17p). This integrated analysis included 271 ibrutinib-treated non-del(17p) patients with CLL (136 TN and 135 R/R). Median progression-free survival (PFS) was not reached for subgroups with 0 and 1/2 prior therapies but was 40.6 months for patients with ≥3 therapies (median follow-up: TN, 36 months; R/R, 44 months). Median overall survival (OS) was not reached in any subgroup. Overall response rate (ORR) was 92% in TN and 92% in R/R, with depth of response increasing over time. Adverse events (AEs) and ibrutinib discontinuation due to AEs were similar between patient groups. Most patients (64%) remain on treatment. OS following discontinuation was 9.3 months in R/R patients (median follow-up 18 months, n = 51) and was not reached in TN patients (median follow-up 10 months, n = 30). In this integrated analysis, ibrutinib was associated with favorable PFS and OS, and high ORR regardless of prior therapies in patients with CLL. The best outcomes following ibrutinib discontinuation were for patients receiving ibrutinib in earlier lines of therapy.

Optogenetic Inhibition of Ventral Pallidum Neurons Impairs Context-Driven Salt Seeking.

Salt appetite, in which animals can immediately seek out salt when under a novel state of sodium deprivation, is a classic example of how homeostatic systems interface with learned associations to produce an on-the-fly updating of motivated behavior. Neural activity in the ventral pallidum (VP) has been shown to encode changes in the value of salt under such conditions, both the value of salt itself (Tindell et al., 2006) and the motivational value of its predictive cues (Tindell et al., 2009; Robinson and Berridge, 2013). However, it is not known whether the VP is necessary for salt appetite in terms of seeking out salt or consuming salt following sodium depletion. Here, we used a conditioned place-preference procedure to investigate the effects of optogenetically inhibiting the VP on context-driven salt seeking and the consumption of salt following deprivation. Male rats learned to associate one context with sucrose and another context with less-desirable salt. Following sodium depletion, and in the absence of either sucrose or salt, we found that inhibiting the VP selectively reduced the elevation in time spent in the salt-paired context. VP inhibition had minimal effects on the consumption of salt once it was made available. To our knowledge, this is the first evidence that the VP or any brain region is necessary for the ability to use contextual cues to guide salt seeking. These results highlight a dissociation between deficit-driven reward seeking and reward consumption to replenish those deficits, with the former process being particularly sensitive to on-line VP activity.SIGNIFICANCE STATEMENT Salt appetite, in which rats will immediately seek out a once-undesirable concentrated salt solution after being depleted of bodily sodium despite never having tasted salt as a positive reward, is a phenomenon showing how animals can update their motivational goals without any new learning or conditioning. This salt-seeking behavior is also observed when the animal is presented with salt-paired cues. The neural circuitry necessary for context-driven salt-seeking behavior is unknown. We used a novel conditioned place preference procedure to show that optogenetic inhibition of the ventral pallidum (VP), a region known for processing reward, impairs context-driven salt seeking and has minimal effects on the consumption of salt itself following sodium depletion. These results highlight the importance of the VP in context-driven reward-seeking behavior.

Automated, high-throughput derivation, characterization and differentiation of induced pluripotent stem cells.

Induced pluripotent stem cells (iPSCs) are an essential tool for modeling how causal genetic variants impact cellular function in disease, as well as an emerging source of tissue for regenerative medicine. The preparation of somatic cells, their reprogramming and the subsequent verification of iPSC pluripotency are laborious, manual processes limiting the scale and reproducibility of this technology. Here we describe a modular, robotic platform for iPSC reprogramming enabling automated, high-throughput conversion of skin biopsies into iPSCs and differentiated cells with minimal manual intervention. We demonstrate that automated reprogramming and the pooled selection of polyclonal pluripotent cells results in high-quality, stable iPSCs. These lines display less line-to-line variation than either manually produced lines or lines produced through automation followed by single-colony subcloning. The robotic platform we describe will enable the application of iPSCs to population-scale biomedical problems including the study of complex genetic diseases and the development of personalized medicines.

Paradoxical accentuation of motivation following accumbens-pallidum disconnection.

The nucleus accumbens (NAc) and ventral pallidum (VP) are reciprocally connected, and activity within this circuit is thought to promote reward learning. Inconsistent with this notion, we find that disconnecting NAc medial shell and VP greatly enhances the attribution of value to a cue that is paired with reward. This result suggests that medial NAc shell and VP are both needed for attributing value to cues yet can also oppose one-another's functional contribution.

An omission procedure reorganizes the microstructure of sign-tracking while preserving incentive salience.

Appetitive sign-tracking, in which reward-paired cues elicit approach that can result in cue interaction, demonstrates how cues acquire motivational value. For example, rats will approach and subsequently interact with a lever insertion cue that signals food delivery upon its retraction. However, lever deflections are rapidly reduced once rats are trained on an omission schedule in which lever interactions cancel food delivery. Here we evaluated the change in sign-tracking response topography in rats exposed to such an omission procedure. Lever deflections dropped precipitously when they canceled reward. However, rats that were on an omission schedule continued to approach, sniff, and contact the lever without pressing it, and did so at comparable rates to rats that were not under an omission schedule. Thus, sign-tracking was maintained, albeit in a different manner, following omission. Such findings show that the motivational attraction to reward cues can be expressed with remarkable persistence and flexibility.

Comparison of magnetic resonance elastography and diffusion-weighted imaging for differentiating benign and malignant liver lesions.

OBJECTIVES: Comparison of magnetic resonance elastography (MRE) and diffusion-weighted imaging (DWI) for differentiating malignant and benign focal liver lesions (FLLs). METHODS: Seventy-nine subjects with 124 FLLs (44 benign and 80 malignant) underwent both MRE and DWI. MRE was performed with a modified gradient-echo sequence and DWI with a free breathing technique (b = 0.500). Apparent diffusion coefficient (ADC) maps and stiffness maps were generated. FLL mean stiffness and ADC values were obtained by placing regions of interest over the FLLs on stiffness and ADC maps. The accuracy of MRE and DWI for differentiation of benign and malignant FLL was compared using receiver operating curve (ROC) analysis. RESULTS: There was a significant negative correlation between stiffness and ADC (r = -0.54, p < 0.0001) of FLLs. Malignant FLLs had significantly higher mean stiffness (7.9kPa vs. 3.1kPa, p < 0.001) and lower mean ADC (129 vs. 200 × 10(-3)mm(2)/s, p < 0.001) than benign FLLs. The sensitivity/specificity/positive predictive value/negative predictive value for differentiating malignant from benign FLLs with MRE (cut-off, >4.54kPa) and DWI (cut-off, <151 × 10(-3)mm(2)/s) were 96.3/95.5/97.5/93.3% (p < 0.001) and 85/81.8/88.3/75% (p < 0.001), respectively. ROC analysis showed significantly higher accuracy for MRE than DWI (0.986 vs. 0.82, p = 0.0016). CONCLUSION: MRE is significantly more accurate than DWI for differentiating benign and malignant FLLs. KEY POINTS: • MRE is superior to DWI for differentiating benign and malignant focal liver lesions. • Benign lesions with large fibrous components may have higher stiffness with MRE. • Cholangiocarcinomas tend to have higher stiffness than hepatocellular carcinomas. • Hepatocellular adenomas tend to have lower stiffness than focal nodular hyperplasia. • MRE is superior to conventional MRI in differentiating benign and malignant liver lesions.

Tips and tricks to avoid bile duct injury in SILC: an experience of 500 cases.

INTRODUCTION: Conventional laparoscopic cholecystectomy is the gold standard surgical treatment for symptomatic gallstones. Surgeons have attempted to minimize the number of incisions via single-incision laparoscopic cholecystectomy (SILC), which offers benefits including improved cosmesis, possibly less postoperative pain, and improved patient satisfaction. However, studies show that there is an increased risk of operative complications-in particular bile duct injuries. We report 500 consecutive cases of SILC performed without bile duct injury. METHODS: A retrospective study of 500 continuous cases of SILC performed by the same surgeon at a single institution was conducted. Data on patient demographics, operative details, and postoperative outcomes were collected and evaluated. Detailed analysis of surgical techniques specifically to reduce bile duct injury was performed and described in this study. RESULTS: In total, 500 patients underwent SILC during the study period. Eight patients needed additional ports to complete the surgery, while one was converted to an open surgery. No serious intraoperative complications, such as bile duct injury, were encountered. CONCLUSION: Our experience shows that with due care and caution during SILC, with particular attention towards achieving the critical view of safety and a standardized technique, bile duct injury in SILC can be avoided.

Chemogenetic manipulation of ventral pallidal neurons impairs acquisition of sign-tracking in rats.

Cues associated with rewarding events acquire value themselves as a result of the incentive value of the reward being transferred to the cue. Consequently, presentation of a reward-paired cue can trigger reward-seeking behaviours towards the cue itself (i.e. sign-tracking). The ventral pallidum (VP) has been demonstrated to be involved in a number of motivated behaviours, both conditioned and unconditioned. However, its contribution to the acquisition of incentive value is unknown. Using a discriminative autoshaping procedure with levers, the effects of disrupting VP activity in rats on the emergence of sign-tracking was investigated using chemogenetics, i.e. Designer Receptors Exclusively Activated by Designer Drugs (DREADDs). Transient disruption of VP neurons [activation of the inhibitory hM4D(Gi) DREADD through systemic injections of clozapine N-oxide (CNO) prior to each autoshaping session] impaired acquisition of sign-tracking (lever press rate) without having any effect on approach to the site of reward delivery (i.e. goal-tracking) or on the expression of sign-tracking after it was acquired. In addition, electrophysiological recordings were conducted in freely behaving rats following VP DREADD activation. The majority of VP units that were responsive to CNO injections exhibited rapid inhibition relative to baseline, a subset of CNO-responsive units showed delayed excitation, and a smaller subset displayed a mixed response of inhibition and excitation following CNO injections. It is argued that disruption of VP during autoshaping specifically disrupted the transfer of incentive value that was attributed to the lever cue, suggesting a surprisingly fundamental role for the VP in acquiring, compared with expressing, Pavlovian incentive values.

A randomized controlled trial comparing post-operative pain in single-incision laparoscopic cholecystectomy versus conventional laparoscopic cholecystectomy.

INTRODUCTION: An increasing body of evidence is being published about single-incision laparoscopic cholecystectomy (SILC), but there are no well-powered trials with an adequate evaluation of post-operative pain. This randomized trial compares SILC against four-port laparoscopic cholecystectomy (LC) with post-operative pain as the primary endpoint. METHODS: Hundred patients were randomized to either SILC (n = 50) or LC (n = 50). Exclusion criteria were (1) Acute cholecystitis; (2) ASA 3 or above; (3) Bleeding disorders; and (4) Previous open upper abdominal surgery. Patients and post-operative assessors were blinded to the procedure performed. The site and severity of pain were compared at 4 h, 24 h, 14 days and 6 months post-procedure using the visual analog scale; non-inferiority was assumed when the lower boundary of the 95% confidence interval of the difference was above -1 and superiority when p ≤ 0.05. RESULTS: The study arms were demographically similar. At 24 h post-procedure, SILC was associated with less pain at extra-umbilical sites (rest: p = 0.004; movement: p = 0.008). Pain data were inconclusive at 24 h at the umbilical site on movement; SILC was otherwise non-inferior for pain at all other points. Operating duration was longer in SILC (79.46 vs 58.88 min, p = 0.003). 8% of patients in each arm suffered complications (p = 1.000). Re-intervention rates, analgesic use, return to function, and patient satisfaction did not differ significantly. CONCLUSIONS: SILC has improved short-term pain outcomes compared to LC and is not inferior in both short-term and long-term pain outcomes. The operating time is longer, but remains feasible in routine surgical practice.

Outcomes of resection of giant hepatocellular carcinoma in a tertiary institution: does size matter?

BACKGROUND: The surgical management of giant hepatocellular carcinoma (G-HCC), or HCC of ≥10 cm in diameter, remains controversial. The aim of this study was to compare the outcomes of surgical resection of, respectively, G-HCC and small HCC (S-HCC), or HCC measuring <10 cm. METHODS: A retrospective review of all patients (n = 86) diagnosed with HCC and submitted to resection in a tertiary hospital during the period from January 2007 to June 2012 was conducted. Overall survival (OS), recurrence rates and perioperative mortality at 30 days were compared between patients with, respectively, G-HCC and S-HCC. Prognostic factors for OS were analysed. RESULTS: The sample included 23 patients with G-HCC (26.7%) and 63 with S-HCC (73.3%) based on histological tumour size. Patient demographics and comorbidities were comparable. Median OS was 39.0 months in patients with G-HCC and 65.0 months in patients with S-HCC (P = 0.213). Although size did not affect OS in this cohort, the presence of satellite lesions [hazard ratio (HR) 3.70, P = 0.012] and perioperative blood transfusion (HR 2.85, P = 0.015) were negative predictors for OS. CONCLUSIONS: Surgical resection of G-HCC provides OS comparable with that after resection of S-HCC.

Metabolic syndrome after a liver transplantation in an Asian population.

BACKGROUND: With improvements in patient survival after a liver transplantation (LT), long-term sequelae such as metabolic syndrome (MS) have become increasingly common. This study aims to characterize the prevalence, associations and long-term outcomes of post-LTMS and its components in an Asian population. METHODS: A retrospective review of all adult patients who underwent LT at the National University Health System Singapore between December 1996 and May 2012 was performed. MS was defined using the Adult Treatment Panel (ATP) III criteria modified for an Asian population. RESULTS: The median age of this cohort of 90 patients was 50.0 (16.0-67.0) years, with a median follow-up duration of 60.0 (7.0-192.0) months. The prevalence of post-LTMS was 35.6%, diabetes mellitus (DM) 51.1%, hypertension 60.0%, obesity 26.7% and dyslipidaemia 46.7%. On univariate analysis, factors significantly associated with post-LT MS include female gender (P = 0.066), pre-LT respiratory comorbidities (P = 0.038), pre-LT obesity (P = 0.014), pre-LTDM (P < 0.001), pre-LT hypertension (P = 0.039), pre-LTMS (P < 0.001), prednisolone use ≥24 months (P = 0.005) and mycophenolate mofetil use ≥24 months (P = 0.035). On multivariate analysis, independent associations of post-LT MS were pre-LTDM (P = 0.011) and pre-LTMS (P = 0.024). There was no difference in long-term survival of patients with and without post-LTMS (P = 0.425). CONCLUSION: In conclusion, pre-LT components of the MS and the use of certain immunosuppressants are related to developing post-LTMS.