HTLV-1 infection in solid organ transplant donors and recipients in Spain.

BACKGROUND: HTLV-1 infection is a neglected disease, despite infecting 10-15 million people worldwide and severe illnesses develop in 10% of carriers lifelong. Acknowledging a greater risk for developing HTLV-1 associated illnesses due to immunosuppression, screening is being widely considered in the transplantation setting. Herein, we report the experience with universal HTLV testing of donors and recipients of solid organ transplants in a survey conducted in Spain. METHODS: All hospitals belonging to the Spanish HTLV network were invited to participate in the study. Briefly, HTLV antibody screening was performed retrospectively in all specimens collected from solid organ donors and recipients attended since the year 2008. RESULTS: A total of 5751 individuals were tested for HTLV antibodies at 8 sites. Donors represented 2312 (42.2%), of whom 17 (0.3%) were living kidney donors. The remaining 3439 (59.8%) were recipients. Spaniards represented nearly 80%. Overall, 9 individuals (0.16%) were initially reactive for HTLV antibodies. Six were donors and 3 were recipients. Using confirmatory tests, HTLV-1 could be confirmed in only two donors, one Spaniard and another from Colombia. Both kidneys of the Spaniard were inadvertently transplanted. Subacute myelopathy developed within 1 year in one recipient. The second recipient seroconverted for HTLV-1 but the kidney had to be removed soon due to rejection. Immunosuppression was stopped and 3 years later the patient remains in dialysis but otherwise asymptomatic. CONCLUSION: The rate of HTLV-1 is low but not negligible in donors/recipients of solid organ transplants in Spain. Universal HTLV screening should be recommended in all donor and recipients of solid organ transplantation in Spain. Evidence is overwhelming for very high virus transmission and increased risk along with the rapid development of subacute myelopathy.

Cooling rate effects on the microstructure, solid content, and rheological properties of organogels of amides derived from stearic and (R)-12-hydroxystearic acid in vegetable oil.

Using safflower oil as the liquid phase, we investigated the organogelation properties of stearic acid (SA), (R)-12-hydroxystearic acid (HSA), and different primary and secondary amides synthesized from SA and HSA. The objective was to establish the relationship between the gelator's molecular structure, solid content, and gels' microstructure that determines the rheological properties of organogels developed at two cooling rates, 1 and 20 °C/min. The results showed that the presence of a 12-OH group in the gelator molecule makes its crystallization kinetics cooling rate dependent and modifies its crystallization behavior. Thus, SA crystallizes as large platelets, while HSA crystallizes as fibers forming gels with higher solid content, particularly at 20 °C/min. The addition to HSA of a primary or a secondary amide bonded with an alkyl group resulted in gelator molecules that crystallized as fibrillar spherulites at both cooling rates. Independent of the cooling rate, gels of HSA and its amide derivatives showed thixotropic behavior. The rheological properties of the amide's organogels depend on a balance between hydrogen-bonding sites and the alkyl chain length bonded to the amide group. However, it might also be associated with the effect that the gelators' molecular weight has on crystal growth and its consequence on fiber interpenetration among vicinal spherulites. These results were compared with those obtained with candelilla wax (CW), a well-known edible gelling additive used by the food industry. CW organogels had higher elasticity than HSA gels but lower than the gels formed by amides. Additionally, CW gels showed similar or even higher thixotropic behavior than HSA and the amide's gels. These remarkable rheological properties resulted from the microstructural organization of CW organogels. We concluded that microstructure has a more important role determining the organogels' rheology than the solid content. The fitting models developed to describe the organogels rheological behavior support this argument.

Aberrant Methylation of the Imprinted C19MC and MIR371-3 Clusters in Patients with Non-Small Cell Lung Cancer.

Epigenetic mechanisms have emerged as an important contributor to tumor development through the modulation of gene expression. Our objective was to identify the methylation profile of the imprinted C19MC and MIR371-3 clusters in patients with non-small cell lung cancer (NSCLC) and to find their potential target genes, as well as to study their prognostic role. DNA methylation status was analyzed in a NSCLC patient cohort (n = 47) and compared with a control cohort including COPD patients and non-COPD subjects (n = 23) using the Illumina Infinium Human Methylation 450 BeadChip. Hypomethylation of miRNAs located on chromosome 19q13.42 was found to be specific for tumor tissue. We then identified the target mRNA-miRNA regulatory network for the components of the C19MC and MIR371-3 clusters using the miRTargetLink 2.0 Human tool. The correlations of miRNA-target mRNA expression from primary lung tumors were analyzed using the CancerMIRNome tool. From those negative correlations identified, we found that a lower expression of 5 of the target genes (FOXF2, KLF13, MICA, TCEAL1 and TGFBR2) was significantly associated with poor overall survival. Taken together, this study demonstrates that the imprinted C19MC and MIR371-3 miRNA clusters undergo polycistronic epigenetic regulation leading to deregulation of important and common target genes with potential prognostic value in lung cancer.

Rise and fall of Landau's quasiparticles while approaching the Mott transition.

Landau suggested that the low-temperature properties of metals can be understood in terms of long-lived quasiparticles with all complex interactions included in Fermi-liquid parameters, such as the effective mass m⋆. Despite its wide applicability, electronic transport in bad or strange metals and unconventional superconductors is controversially discussed towards a possible collapse of the quasiparticle concept. Here we explore the electrodynamic response of correlated metals at half filling for varying correlation strength upon approaching a Mott insulator. We reveal persistent Fermi-liquid behavior with pronounced quadratic dependences of the optical scattering rate on temperature and frequency, along with a puzzling elastic contribution to relaxation. The strong increase of the resistivity beyond the Ioffe-Regel-Mott limit is accompanied by a 'displaced Drude peak' in the optical conductivity. Our results, supported by a theoretical model for the optical response, demonstrate the emergence of a bad metal from resilient quasiparticles that are subject to dynamical localization and dissolve near the Mott transition.

Efficacy of nintedanib plus docetaxel in patients with refractory advanced epidermal growth factor receptor mutant lung adenocarcinoma.

BACKGROUND: Anti-angiogenic agents are reported to exert clinical activity in patients with epidermal growth factor receptor (EGFR) mutant non-small cell lung cancer (NSCLC). We evaluated the outcomes of the combination of docetaxel plus nintedanib in refractory NSCLC patients harboring EGFR mutations. METHODS: We retrospectively analyzed 19 patients with advanced EGFR-mutant NSCLC who had progressed to EGFR tyrosine kinase inhibitors (TKI) and platinum-based chemotherapy receiving docetaxel and nintedanib at 14 Spanish institutions from January 2013 to December 2019. Kaplan-Meier and log-rank tests were used to evaluate progression-free survival (PFS) and overall survival (OS). RESULTS: Median age was 58.9 years (range 42.8-81), 73.7% were female. All patients were Caucasian, and 73.7% were never or light smokers. The baseline Eastern Cooperative Oncology Group (ECOG) performance status (PS) was 0-1 in 94.7% of patients. All patients had adenocarcinoma. Brain and liver metastases were present in 47.4% and 31.6% of patients, respectively. The most common EGFR mutations were exon 19 deletion (52.6%) and exon 21 L858R mutation (36.8%); 47.4% patients presented the EGFR T790M. 94.8% of the patients had received 2-3 previous treatment lines. Docetaxel was administered at 75 mg/m2/3 weeks to 16 patients, at 60 mg/m2 to 2 patients and at 45 mg/m2 to one patient. Nintedanib was given until disease progression or unacceptable toxicity at 200 mg twice daily except in 2 patients who received 150 mg twice daily and one patient who received 100 mg/12 h. With a median follow-up of 11.4 months (1-38), the median PFS was 6.1 months [95% confidence interval (CI), 4.9-7.3] and the median OS 10.1 months (95% CI 5.9-14.3). The objective response rate (ORR) was 44.4% (23.7-66.8%) and the disease control rate (DCR) 72.2% (49.4-88.5%). Efficacy tended to be greater in patients with the acquired T790M who had received osimertinib, with a median PFS of 6.3 (95% CI 2.1-10.5) versus (vs.) 4.8 (95% CI 3.5-6.1) and a median OS of 12.3 months (95% CI 8.6-16.0) vs. 6.7 months (95% CI 3.9-9.4), although this tendency was not statistically significant (p = 0.468 and p = 0.159, respectively). Sixteen patients (84.2%) had a total of 34 adverse events (AEs), with a median of two (0-6) AEs per patient. The most frequent AEs were asthenia (20.6%) and diarrhea (20.6%). One treatment-related death due to portal thrombosis was reported. CONCLUSIONS: Our data indicate that the combination of docetaxel and nintedanib can be considered to be an effective treatment for EGFR TKI-resistant EGFR-mutant NSCLC.

Primary and Acquired Resistance to Immunotherapy in Lung Cancer: Unveiling the Mechanisms Underlying of Immune Checkpoint Blockade Therapy.

After several decades without maintained responses or long-term survival of patients with lung cancer, novel therapies have emerged as a hopeful milestone in this research field. The appearance of immunotherapy, especially immune checkpoint inhibitors, has improved both the overall survival and quality of life of patients, many of whom are diagnosed late when classical treatments are ineffective. Despite these unprecedented results, a high percentage of patients do not respond initially to treatment or relapse after a period of response. This is due to resistance mechanisms, which require understanding in order to prevent them and develop strategies to overcome them and increase the number of patients who can benefit from immunotherapy. This review highlights the current knowledge of the mechanisms and their involvement in resistance to immunotherapy in lung cancer, such as aberrations in tumor neoantigen burden, effector T-cell infiltration in the tumor microenvironment (TME), epigenetic modulation, the transcriptional signature, signaling pathways, T-cell exhaustion, and the microbiome. Further research dissecting intratumor and host heterogeneity is necessary to provide answers regarding the immunotherapy response and develop more effective treatments for lung cancer.

The Roles of Imprinted SLC22A18 and SLC22A18AS Gene Overexpression Caused by Promoter CpG Island Hypomethylation as Diagnostic and Prognostic Biomarkers for Non-Small Cell Lung Cancer Patients.

Genomic imprinting is a process that involves one gene copy turned-off in a parent-of-origin-dependent manner. The regulation of imprinted genes is broadly dependent on promoter methylation marks, which are frequently associated with both oncogenes and tumor suppressors. The purpose of this study was to assess the DNA methylation patterns of the imprinted solute-carrier family 22 member 18 (SLC22A18) and SLC22A18 antisense (SLC22A18AS) genes in non-small cell lung cancer (NSCLC) patients to study their relevance to the disease. We found that both genes were hypomethylated in adenocarcinoma and squamous cell carcinoma patients. Due to this imprinting loss, SLC22A18 and SLC22A18AS were found to be overexpressed in NSCLC tissues, which is significantly more evident in lung adenocarcinoma patients. These results were validated through analyses of public databases of NSCLC patients. The reversed gene profile of both genes was achieved in vitro by treatment with ademetionine. We then showed that high SLC22A18 and SLC22A18AS expression levels were significantly associated with worsening disease progression. In addition, low levels of SLC22A18AS were also correlated with better overall survival for lung adenocarcinoma patients. We found that SLC22A18 and SLC22A18AS knockdown inhibits cell proliferation in vitro. All these results suggest that both genes may be useful as diagnostic and prognostic biomarkers in NSCLC, revealing novel therapeutic opportunities.

A phase II randomized, multicenter, open-label trial of continuing adjuvant temozolomide beyond 6 cycles in patients with glioblastoma (GEINO 14-01).

BACKGROUND: Standard treatment for glioblastoma is radiation with concomitant and adjuvant temozolomide for 6 cycles, although the optimal number of cycles of adjuvant temozolomide has long been a subject of debate. We performed a phase II randomized trial investigating whether extending adjuvant temozolomide for more than 6 cycles improved outcome. METHODS: Glioblastoma patients treated at 20 Spanish hospitals who had not progressed after 6 cycles of adjuvant temozolomide were centrally randomized to stop (control arm) or continue (experimental arm) temozolomide up to a total of 12 cycles at the same doses they were receiving in cycle 6. Patients were stratified by MGMT methylation and measurable disease. The primary endpoint was differences in 6-month progression-free survival (PFS). Secondary endpoints were PFS, overall survival (OS), and safety (Clinicaltrials.gov NCT02209948). RESULTS: From August 2014 to November 2018, 166 patients were screened, 7 of whom were ineligible. Seventy-nine patients were included in the stop arm and 80 in the experimental arm. All patients were included in the analyses of outcomes and of safety. There were no differences in 6-month PFS (control 55.7%; experimental 61.3%), PFS, or OS between arms. MGMT methylation and absence of measurable disease were independent factors of better outcome. Patients in the experimental arm had more lymphopenia (P < 0.001), thrombocytopenia (P < 0.001), and nausea and vomiting (P = 0.001). CONCLUSIONS: Continuing temozolomide after 6 adjuvant cycles is associated with greater toxicity but confers no additional benefit in 6-month PFS. KEY POINTS: 1. Extending adjuvant temozolomide to 12 cycles did not improve 6-month PFS.2. Extending adjuvant temozolomide did not improve PFS or OS in any patient subset.3. Extending adjuvant temozolomide was linked to increased toxicities.

Rapid subacute myelopathy following kidney transplantation from HTLV-1 donors: role of immunosuppresors and failure of antiretrovirals.

Two kidney transplant recipients from a single donor became infected with HTLV-1 (human T-lymphotropic virus type 1) in Spain. One developed myelopathy 8 months following surgery despite early prescription of antiretroviral therapy. The allograft was removed from the second recipient at month 8 due to rejection and immunosuppressors discontinued. To date, 3 years later, this patient remains infected but asymptomatic. HTLV-1 infection was recognized retrospectively in the donor, a native Spaniard who had sex partners from endemic regions. Our findings call for a reappraisal of screening policies on donor-recipient organ transplantation. Based on the high risk of disease development and the large flux of persons from HTLV-1 endemic regions, pre-transplant HTLV-1 testing should be mandatory in Spain.

Salicylamide derivatives for iron and aluminium sequestration. From synthesis to complexation studies.

This paper presents an easy, fast and economic synthesis of chelating agents for medical, environmental and analytical applications, and the evaluation of the stability of their complexes with Fe3+ and Al3+. Complex formation equilibria with Cu2+ and Zn2+ metal ions were also studied to evaluate if the chelating agents can perturb the homeostatic equilibria of these essential metal ions. Effective chelating agents for metal ions, in addition to their well-known medical uses, find an increasing number of applications in environmental remediation, agricultural applications (supplying essential elements in an easily available form), and in analytical chemistry as colorimetric reagents. Besides the stability of the complexes, the lack of toxicity and the low cost are the basic requisites of metal chelating agents. With these aims in mind, we utilized ethyl salicylate, a cheap molecule without toxic effects, and adopted a simple synthetic strategy to join two salicylate units through linear diamines of variable length. Actually, the mutual position of the metal binding oxygen groups, as well as the linker length, affected protonation and complex formation equilibria. A thorough study of the ligands is presented. In particular, the complex formation equilibria of the three ligands toward Fe3+, Al3+, Zn2+ and Cu2+ ions were investigated by combined potentiometric and spectrophotometric techniques. The results are encouraging: all the three ligands form stable complexes with all the investigated metal ions, involving the oxygen donor atoms from the 2-hydroxybenzamido unit, and nitrogen atoms in copper and zinc coordination.

A randomized, phase 2 evaluation of the CHK1 inhibitor, LY2603618, administered in combination with pemetrexed and cisplatin in patients with advanced nonsquamous non-small cell lung cancer.

This phase 2 portion of a phase 1/2 study examined the efficacy and safety of LY2603618, a selective checkpoint kinase 1 inhibitor, combined with pemetrexed and cisplatin (LY+Pem+Cis) in patients with advanced nonsquamous non-small cell lung cancer (NSCLC). This multicenter, randomized, controlled, open-label study (NCT01139775) enrolled patients with stage IV nonsquamous NSCLC and an Eastern Cooperative Oncology Group performance status ≤1. Patients were randomized (2:1) to LY+Pem+Cis or pemetrexed and cisplatin (Pem+Cis). Induction therapy comprised four 21-day cycles of 500 mg/m2 pemetrexed and 75mg/m2 cisplatin on Day 1 (both arms) and 275mg LY2603618 on Day 2 (LY+Pem+Cis arm). Maintenance therapy comprised 500mg/m2 pemetrexed on Day 1 (both arms) and 275mg LY2603618 on Day 2 (LY+Pem+Cis arm) until disease progression. The primary endpoint was progression-free survival (PFS). Enrollment was permanently halted before target enrollment was met due to a greater number of thromboembolic events in the LY+Pem+Cis arm. Sixty-two patients were enrolled (LY+Pem+Cis, n=39; Pem+Cis, n=23). Bayesian and frequentist analysis demonstrated superior PFS in the LY+Pem+Cis arm vs the Pem+Cis arm (median [90% confidence interval]: LY+Pem+Cis, 4.7 months [4.-7.1]; Pem+Cis, 1.5 months [1.3-2.9]; P=0.022). Seven patients in the LY+Pem+Cis arm (vs 0 in the Pem+Cis arm) experienced serious thromboembolic events: pulmonary embolism (n=5), ischemic stroke (n=1), and cerebrovascular accident (n=1). Although the primary endpoint was met, the combination of LY2603618+Pem+Cis will not be further developed for treating advanced nonsquamous NSCLC due to the potential increased risk of thromboembolic events with this combination. ClinicalTrials.gov Identifier: NCT01139775.

Human T-lymphotropic virus type 1 infection and disease in Spain.

: Human T-lymphotropic virus type 1 (HTLV-1) infection is a neglected disease despite roughly 15 million people are chronically infected worldwide. Lifelong less than 10% of carriers develop life-threatening diseases, mostly a subacute myelopathy known as tropical spastic paraparesis (TSP) and a lymphoproliferative disorder named adult T-cell leukemia (ATL). HTLV-1 is efficiently transmitted perinatally (breastfeeding), sexually (more from men to women) and parenterally (transfusions, injection drug user (IDU), and transplants). To date there is neither prophylactic vaccine nor effective antiviral therapy. A total of 327 cases of HTLV-1 infection had been reported at the HTLV-1 Spanish registry until December 2016, of whom 34 had been diagnosed with TSP and 25 with ATL. Overall 62% were Latin American immigrants and 13% were persons of African origin. The incidence of HTLV-1 in Spain has remained stable for nearly a decade with 20-25 new cases yearly. Of the 21 newly diagnosed HTLV-1 cases during year 2016, one was a native Spaniard pregnant woman, and four presented with symptomatic disease, including three with ATL and one with TSP. Underdiagnosis of HTLV-1 in Spain must be high (iceberg model), which may account for the disproportionate high rate of symptomatic cases (almost 20%) and the late recognition of preventable HTLV-1 transmissions in special populations, such as newborns and transplant recipients. Our current estimate is of 10 000 persons living with HTLV-1 infection in Spain. Given the large flux of immigrants and visitors from HTLV-1 endemic regions to Spain, the expansion of HTLV-1 screening policies is warranted. At this time, it seems worth recommending HTLV testing to all donor/recipient organ transplants and pregnant women regardless place of birth. Although current leukoreduction procedures largely prevent HTLV-1 transmission by blood transfusions, HTLV testing of all first-time donors should be cost-effective contributing to unveil asymptomatic unaware HTLV-1 carriers.

Using NS5B Sequencing for Hepatitis C Virus Genotyping Reveals Discordances with Commercial Platforms.

We aimed to evaluate the correct assignment of HCV genotypes by three commercial methods-Trugene HCV genotyping kit (Siemens), VERSANT HCV Genotype 2.0 assay (Siemens), and Real-Time HCV genotype II (Abbott)-compared to NS5B sequencing. We studied 327 clinical samples that carried representative HCV genotypes of the most frequent geno/subtypes in Spain. After commercial genotyping, the sequencing of a 367 bp fragment in the NS5B gene was used to assign genotypes. Major discrepancies were defined, e.g. differences in the assigned genotype by one of the three methods and NS5B sequencing, including misclassification of subtypes 1a and 1b. Minor discrepancies were considered when differences at subtype levels, other than 1a and 1b, were observed. The overall discordance with the reference method was 34% for Trugene and 15% for VERSANT HCV2.0. The Abbott assay correctly identified all 1a and 1b subtypes, but did not subtype all the 2, 3, 4 and 5 (34%) genotypes. Major discordances were found in 16% of cases for Trugene HCV, and the majority were 1b- to 1a-related discordances; major discordances were found for VERSANT HCV 2.0 in 6% of cases, which were all but one 1b to 1a cases. These results indicated that the Trugene assay especially, and to a lesser extent, Versant HCV 2.0, can fail to differentiate HCV subtypes 1a and 1b, and lead to critical errors in clinical practice for correctly using directly acting antiviral agents.

An NMR study on the 6,6'-(2-(diethylamino)ethylazanediyl)bis(methylene)bis(5-hydroxy-2-hydroxymethyl-4H-pyran-4-one) interaction with Al(III) and Zn(II) ions.

Here we report about the complex formation among an amine-bearing bis-kojic acid, 6,6'-(2-(diethylamino)ethylazanediyl)bis(methylene)bis(5-hydroxy-2-hydroxymethyl-4H-pyran-4-one) and two metal ions, the trivalent hard and not essential metal ion Al(III) and the borderline and essential divalent metal ion Zn(II). We carried out a thorough NMR study in order to reach the indispensable structural information on the behavior of these complexes in solution. A combination of 1D, 2D total correlation spectroscopy, heteronuclear single quantum coherence spectroscopy, nuclear Overhauser enhancement spectroscopy and rotating-frame Overhauser effect spectroscopy experiments was used to assign the signals of both free and metal-bound ligand at different pH values. Our results highlighted the different coordination behaviors of the ligand towards the different metal ions, depending on their hard or borderline character. The trivalent metal ion, Al(III), mainly forms dinuclear helicate complexes of M2L3 stoichiometry, and the coordination only involves both hydroxypyrone (O,O)-donor atoms. NMR data are in agreement with the presence of a rigid and symmetric structure of L9-Al(III) complexes up to physiological pH. On the contrary, with the divalent metal ion, NMR data showed the coexistence of several species in solution though Zn(II) forms complexes of ML stoichiometry at physiological pH, where the metal coordination involves the nitrogen atoms of both the linker and the side-chain amine groups together with the oxygen atoms of phenolate groups. The in solution study will be of interest for providing an insight on the ligand bioavailability and on its behavior in the chelation treatments.

A Speciation Study on the Perturbing Effects of Iron Chelators on the Homeostasis of Essential Metal Ions.

A number of reports have appeared in literature calling attention to the depletion of essential metal ions during chelation therapy on ß-thalassaemia patients. We present a speciation study to determine how the iron chelators used in therapy interfere with the homeostatic equilibria of essential metal ions. This work includes a thorough analysis of the pharmacokinetic properties of the chelating agents currently in clinical use, of the amounts of iron, copper and zinc available in plasma for chelation, and of all the implied complex formation constants. The results of the study show that a significant amount of essential metal ions is complexed whenever the chelating agent concentration exceeds the amount necessary to coordinate all disposable iron--a frequently occurring situation during chelation therapy. On the contrary, copper and zinc do not interfere with iron chelation, except for a possible influence of copper on iron speciation during deferiprone treatment.

Hypoglycemia as a barrier to glycemic control.

Diabetes mellitus is associated with significant morbidity and mortality derived from long-term microvascular and macrovascular complications of chronic hyperglycemia. The Diabetes Control and Complications Trial (DCCT) and the UK Prospective Diabetes Study (UKPDS) have clearly shown the benefits of intensive glycemic control for preventing or delaying the development and progression of long-term complications. However, intensive glycemic control, particularly with insulin therapy, is associated with an increased incidence of hypoglycemia, which is the major barrier to the implementation of intensive treatment from the physician's and patient's perspective. Avoiding the use of intensive treatment most often precludes optimal glycemic control. Some of the many underlying causes of hypoglycemia are defective and deficient counterregulatory responses, relative hyperinsulinization owing to a missed meal, excessive or unplanned exercise, erroneous insulin dosages, excessive insulinotropic effects of some oral secretagogues, and the failure of traditional insulin preparations to simulate the physiologic patterns of endogenous basal insulin secretion found in nondiabetic individuals. Additionally, patient involvement is critical to intensive glycemic control and should involve frequent self-monitoring of blood glucose (SMBG), adherence to treatment regimens, and knowledge of the interrelationship among physical activity, diet, and insulin. This review summarizes the current knowledge on hypoglycemia with a focus on the improvements in insulin therapy (i.e., the mealtime and basal insulin analogs) that may produce more normal physiologic insulin profiles with an attendant lower risk of hypoglycemia than that currently seen in clinical practice.

[Biomarkers of vascular inflammation and subclinical atherosclerosis in the metabolic syndrome]. / Marcadores biológicos de inflamación vascular y aterosclerosis subclínica en el síndrome metabólico.

BACKGROUND AND OBJECTIVE: The metabolic syndrome (MS) is linked to an increase of cardiovascular mortality and morbidity, the pathological substrate of cardiovascular events being atherosclerosis. Inflammatory phenomena play a role in the genesis of atherosclerosis. The aim of this study was to analyze the vascular (adhesins) and systemic [interleukins, amyloid A serum protein (AAS), C reactive protein (PCR)] inflammation markers as well as hemodynamic parameters and the presence or absence of subclinical atherosclerosis measured by intima-media thickness (TIM) determination in MS. PATIENTS AND METHOD: In this transversal study we enrolled 29 patients (18 men,11 women) with a diagnosis of MS. We assessed interleukins (IL-1beta, IL-6, TNF-alpha, TGF-beta, MCP-1), intercellular and intervascular adhesions molecules (sICAM-1, sVCAM-1), systemic inflammation markers (PCR, AAS), microalbuminuria and, as a lipidic oxidation marker, urinary F2 isoprostanes (F2I). TIM was measured by ultrasounds. Ten healthy people with a similar age were included as a control group. RESULTS: Patients with MS, when compared with the control group, showed higher levels of homocysteine (10 [0.5] vs 7.9 [0.5] micromol/l; p < 0.05), sICAM1 (263 [13] vs 203 [14] ng/ml; p < 0.01), IL-6 (7.1 [0.5] vs 4.6 [0.6] pg/ml; p < 0.05), TGF-beta (34 [1.7] vs 26 [1.4] ng/ml; p < 0.01), PCR (0.69 [0.07] vs 0.23 [0.03] mg/dl; p < 0.001), AAS (9.7 [0.7] vs 6.7 [0.7] microg/ml; p < 0.01), microalbuminuria (32 [13] vs 3.2 [0.14] mg/g creatinine; p < 0.05), and F2I (22.4 [2.5] vs 9.1 [0.69] pg/mg creatinine; p < 0.001). TIM in the MS group was greater than in the control group (1.14 [0.14] vs 0.79 [0.02] mm; p < 0.05). F2I values were directly correlated with TIM, systolic arterial pressure and pulse pressure. CONCLUSIONS: Our results show that in MS there is an increase of vascular inflammation and lipooxidation markers and a higher prevalence of subclinical atherosclerosis.

Mapping the homodimer interface of an optimized, artificial, transmembrane protein activator of the human erythropoietin receptor.

Transmembrane proteins constitute a large fraction of cellular proteins, and specific interactions involving membrane-spanning protein segments play an important role in protein oligomerization, folding, and function. We previously isolated an artificial, dimeric, 44-amino acid transmembrane protein that activates the human erythropoietin receptor (hEPOR) in trans. This artificial protein supports limited erythroid differentiation of primary human hematopoietic progenitor cells in vitro, even though it does not resemble erythropoietin, the natural ligand of this receptor. Here, we used a directed-evolution approach to explore the structural basis for the ability of transmembrane proteins to activate the hEPOR. A library that expresses thousands of mutants of the transmembrane activator was screened for variants that were more active than the original isolate at inducing growth factor independence in mouse cells expressing the hEPOR. The most active mutant, EBC5-16, supports erythroid differentiation in human cells with activity approaching that of EPO, as assessed by cell-surface expression of glycophorin A, a late-stage marker of erythroid differentiation. EBC5-16 contains a single isoleucine to serine substitution at position 25, which increases its ability to form dimers. Genetic studies confirmed the importance of dimerization for activity and identified the residues constituting the homodimer interface of EBC5-16. The interface requires a GxxxG dimer packing motif and a small amino acid at position 25 for maximal activity, implying that tight packing of the EBC5-16 dimer is a crucial determinant of activity. These experiments identified an artificial protein that causes robust activation of its target in a natural host cell, demonstrated the importance of dimerization of this protein for engagement of the hEPOR, and provided the framework for future structure-function studies of this novel mechanism of receptor activation.