A CD25-biased interleukin-2 for autoimmune therapy engineered via a semi-synthetic organism.

BACKGROUND: Natural cytokines are poorly suited as therapeutics for systemic administration due to suboptimal pharmacological and pharmacokinetic (PK) properties. Recombinant human interleukin-2 (rhIL-2) has shown promise for treatment of autoimmune (AI) disorders yet exhibits short systemic half-life and opposing immune responses that negate an appropriate therapeutic index. METHODS: A semi-synthetic microbial technology platform was used to engineer a site-specifically pegylated form of rhIL-2 with enhanced PK, specificity for induction of immune-suppressive regulatory CD4 + T cells (Tregs), and reduced stimulation of off-target effector T and NK cells. A library of rhIL-2 molecules was constructed with single site-specific, biorthogonal chemistry-compatible non-canonical amino acids installed near the interface where IL-2 engages its cognate receptor ßγ (IL-2Rßγ) signaling complex. Biorthogonal site-specific pegylation and functional screening identified variants that retained engagement of the IL-2Rα chain with attenuated potency at the IL-2Rßγ complex. RESULTS: Phenotypic screening in mouse identifies SAR444336 (SAR'336; formerly known as THOR-809), rhIL-2 pegylated at H16, as a potential development candidate that specifically expands peripheral CD4+ Tregs with upregulation of markers that correlate with their suppressive function including FoxP3, ICOS and Helios, yet minimally expands CD8 + T or NK cells. In non-human primate, administration of SAR'336 also induces dose-dependent expansion of Tregs and upregulated suppressive markers without significant expansion of CD8 + T or NK cells. SAR'336 administration reduces inflammation in a delayed-type hypersensitivity mouse model, potently suppressing CD4+ and CD8 + T cell proliferation. CONCLUSION: SAR'336 is a specific Treg activator, supporting its further development for the treatment of AI diseases.

Interleukin-2 (IL-2) is a protein that functions as a master regulator of immune responses. A key function of IL-2 is the stimulation of immune-regulatory cells that suppress autoimmune disease, which occurs when the body's immune system mistakenly attacks healthy tissues. However, therapeutic use of IL-2 is limited by its short duration of action and incomplete selectivity for immune-suppressive cells over off-target immune-stimulatory cells. We employ a platform that we have previously developed, which is a bacterial organism with an expanded DNA code, to identify a new version of IL-2, SAR444336 (SAR'336), with an extended duration of activity and increased selectivity for immune-suppressive cells. In mice and monkeys, SAR'336 was a specific activator of immune suppression, with minimal effect on immune cells that stimulate autoimmunity. Our results support further development of SAR'336 for treatment of autoimmune disorders.

Sex Differences in Chronic Thromboembolic Pulmonary Hypertension. Treatment Options over Time in a National Referral Center.

(1) Background: Clinical presentation, disease distribution, or treatment received may provide insights into the reasons contributing to sex differences in chronic thromboembolic pulmonary hypertension (CTEPH). (2) Methods: We evaluated 453 patients (56% women) between 2007-2019. Data was collected from REHAP (Registro Español de Hipertensión Arterial Pulmonar) registry. Two time periods were selected to evaluate the influence of new treatments over time. (3) Results: Women were older. Baseline functional class was worse, and distance walked shorter in women compared with men. Women had higher pulmonary vascular resistances. Despite this, pulmonary endarterectomy (PEA) was carried out in more men, and women received more frequently pulmonary vasodilators exclusively. The 2014-2019 interval was associated with a better survival only among women. Interestingly, women had a more distal disease during this second period of time. (4) Conclusions: Even though women were older, and received invasive treatments less frequently, mortality was similar in both sexes. The introduction of balloon pulmonary angioplasty and the improvement of pulmonary endarterectomy, especially during the last years, could be associated with a survival benefit among women.

Eradication of Staphylococcus aureus Post-Sternotomy Mediastinitis Following the Implementation of Universal Preoperative Nasal Decontamination With Mupirocin: An Interrupted Time-Series Analysis.

BACKGROUND: Although presurgical nasal decontamination with mupirocin (NDM) has been advocated as a measure for preventing postsurgical mediastinitis (PSM) due to Staphylococcus aureus, this strategy is not universally recommended due to lack of robust supporting evidence. We aimed to evaluate the role of preoperative NDM in the annual incidence of S. aureus PSM at our institution. METHODS: An interrupted time-series analysis, with an autoregressive error model, was applied to our single-center cohort by comparing preintervention (1990-2003) and postintervention (2005-2018) periods. Logistic regression was performed to analyze risk factors for S. aureus PSM. RESULTS: 12 236 sternotomy procedures were analyzed (6370 [52.1%] and 5866 [47.9%] in the pre- and postintervention periods, respectively). The mean annual percentage adherence to NDM estimated over the postintervention period was 90.2%. Only 4 of 127 total cases of S. aureus PSM occurred during the 14-year postintervention period (0.68/1000 sternotomies vs 19.31/1000 in the preintervention period; P < .0001). Interrupted time-series analysis demonstrated a statistically significant annual reduction in S. aureus PSM of -9.85 cases per 1000 sternotomies (-13.17 to -6.5; P < .0001) in 2005, with a decreasing trend maintained over the following 5 years and an estimated relative reduction of 84.8% (95% confidence interval [CI], 89.25-74.09%). Chronic obstructive pulmonary disease was the single independent risk factor for S. aureus PSM (odds ratio, 3.7; 95% CI, 1.72-7.93) and was equally distributed in patients undergoing sternotomy during pre- or postintervention periods. CONCLUSIONS: Our experience suggests the implementation of preoperative NDM significantly reduces the incidence of S. aureus PSM.

Feasibility of a Noninvasive Operability Assessment in Chronic Thromboembolic Pulmonary Hypertension under Real-World Practice.

This study aimed to evaluate the feasibility of a noninvasive operability assessment of chronic thromboembolic pulmonary hypertension (CTEPH) based on multidetector computed tomographic angiography (MCTA). Up to 176 patients were evaluated from January 2016 to April 2018. Throughout the first phase, the initial surgical decision was made based on MCTA with further analysis of pulmonary angiography (PA) in order to evaluate in which cases the initial decision was not modified by PA. During the second phase, PA was limited to patients judged inoperable based on MCTA or those whose assessment was not possible. Patients deemed operable (50%) based on MCTA along the first phase had been adequately classified, as PA did not modify the initial decision in all but one patient. Comparable results were obtained throughout the implementation phase. Regarding operated patients, the decision of operability was based solely on MCTA in 94% of those with level I disease, in 75% with level II, and 54% with level III. This approach enabled shorter periods of time to complete surgical assessment and the avoidance of PA-related morbidity. Baseline parameters, postoperative measures, and survival rates at 1 year after surgery were comparable in both phases. Noninvasive operability assessment is feasible in a subset of CTEPH patients and optimizes surgical candidacy evaluation.

Choriocarcinoma Syndrome as an Initial Presentation of Testicular Cancer.

Choriocarcinoma syndrome (CS) is a rare clinical entity within the spectrum of nonseminomatous germ-cell tumors (NSGCT). It is characterized by the abrupt establishment of rapidly progressive and hemorrhagic tumors associated with very high levels of the beta fraction of human chorionic gonadotropin (ß-hCG) and with a very poor prognosis, particularly in patients with ß-hCG values above 50,000 IU/L. We present the case of a 17-year-old man with a sudden onset nonmassive hemoptysis. Physical examination revealed a right testicular mass. Imaging studies showed metastatic lung, bone, and retroperitoneal disease. ß-hCG serum levels were 222,493.21 IU/L, AFP 1.56 ng/mL, and DHL 457 IU/L. Histopathological study after right radical orchiectomy showed a mixed germ-cell tumor. Based on poor-risk characteristics, chemotherapy was started with an adequate clinical response. Physicians should be aware of the potential complications of CS in the treatment of testicular cancer with high ß-hCG levels since they could be associated with a rapidly progressive and high-volume disease. Patients in this category should be referred to the centers experienced in the treatment of advanced germ-cell tumors. Due to the severity of the presentation, hemodynamic monitoring, ideally in an intensive care unit, is essential as well as timely administration of cytotoxic treatment.

Incidence, Risk Factors and Outcomes of Early Acute Kidney Injury After Heart Transplantation: An 18-year Experience.

BACKGROUND: Little is known about the incidence of acute kidney injury (AKI), as defined using the Kidney Disease Improving Global Outcome classification, after heart transplantation (HT). Our objective was to evaluate the impact of AKI in a cohort of HT recipients. (Setting: University Hospital.) METHODS: We studied 310 consecutive HT recipients from 1999 to 2017, with AKI being defined according to the Kidney Disease Improving Global Outcome criteria. Risk factors were analyzed by multivariable analyses, and survival by Kaplan-Meier curves and a risk-adjusted Cox proportional hazards regression model. RESULTS: One hundred twenty-five (40.3%) patients developed AKI, with 73 (23.5%), 18 (5.8%), and 34 (11%) patients having AKI stages 1, 2, and 3, respectively. Cardiac tamponade (odds ratio [OR], 16.82; 95% confidence interval [CI], 1.06-138), acute right ventricular failure (OR, 3.54; 95% CI, 1.82-6.88), and major bleeding (OR, 2.46; 95% CI, 1.18-5.1) were the principal risk factors for AKI. Patients with AKI had a greater hospital mortality (3.8% vs 16%, P < 0.05), especially those requiring renal replacement therapy (46.9% vs 5.4%, P = 0.006). Acute kidney injury requiring renal replacement therapy was independently associated with hospital mortality (OR, 11.03; 95% CI, 4.08-29.8). With a median follow-up after hospital discharge of 6.7 years (interquartile range, 2.4-11.6), overall survival at 1, 5, and 10 years was 95.4%, 85.1%, and 75.4% versus 85.2%, 69.8% and 63.5% among patients without AKI and with AKI stages 2 to 3, respectively (P = 0.08). CONCLUSIONS: The onset of AKI after HT is mainly associated with postoperative complications. Only severe AKI stage predicts worse short-term outcome, with this impact appearing to be lost at long-term follow-up.

Low HLA binding of diabetes-associated CD8+ T-cell epitopes is increased by post translational modifications.

BACKGROUND: Type 1 diabetes (T1D) is thought to be an autoimmune disease driven by anti-islet antigen responses and mediated by T-cells. Recent published data suggests that T-cell reactivity to modified peptides, effectively neoantigens, may promote T1D. These findings have given more credence to the concept that T1D may not be solely an error of immune recognition but may be propagated by errors in protein processing or in modifications to endogenous peptides occurring as result of hyperglycemia, endoplasmic reticulum (ER) stress, or general beta cell dysfunction. In the current study, we hypothesized that diabetes-associated epitopes bound human leukocyte antigen (HLA) class I poorly and that post-translational modifications (PTM) to key sequences within the insulin-B chain enhanced peptide binding to HLA class I, conferring the CD8+ T-cell reactivity associated with T1D. RESULTS: We first identified, through the Immune Epitope Database (IEDB; www.iedb.org ), 138 published HLA class I-restricted diabetes-associated epitopes reported to elicit positive T-cell responses in humans. The peptide binding affinity for their respective restricting allele(s) was evaluated in vitro. Overall, 75% of the epitopes bound with a half maximal inhibitory concentration (IC50) of 8250 nM or better, establishing a reference affinity threshold for HLA class I-restricted diabetes epitopes. These studies demonstrated that epitopes from diabetes-associated antigens bound HLA with a lower affinity than those of microbial origin (binding threshold of 500 nM for 85% of the epitopes). Further predictions suggested that diabetes epitopes also bind HLA class I with lower affinity than epitopes associated with other autoimmune diseases. Therefore, we measured the effect of common PTM (citrullination, chlorination, deamidation, and oxidation) on HLA-A*02:01 binding of insulin-B-derived peptides, compared to native peptides. We found that these modifications increased binding for 44% of the insulin-B epitopes, but only 15% of the control peptides. CONCLUSIONS: These results demonstrate that insulin-derived epitopes, commonly associated with T1D, generally bind HLA class I poorly, but can be subject to PTM that improve their binding capacity and may, in part, be responsible for T-cell activation in T1D and subsequent beta cell death.

Testicular Cancer Presenting as Gastric Variceal Hemorrhage.

Testicular cancer is the most common solid malignancy affecting males between the ages of 15 and 35. The symptomatology caused by this tumor varies according to the site of metastasis. We present the case of a 26-year-old male who arrived to the emergency department with hematemesis. He had no previous medical history. On arrival, we noted enlargement of the left scrotal sac. There was also a mass in the left scrotum which provoked displacement of the penis and right testis. The serum alpha-fetoprotein level was 17,090 ng/mL, lactate dehydrogenase was 1480 U/L, and human chorionic gonadotropin was 287.4 IU/mL. Upper endoscopy revealed a type 1 isolated gastric varix, treated with cyanoacrylate. A CT scan showed extrinsic compression of the portal vein by lymphadenopathy along with splenic vein partial thrombosis, which caused left-sided portal hypertension. Neoadjuvant chemotherapy was started with etoposide and cisplatin, and seven days later the patient underwent left radical orchiectomy. A postoperative biopsy revealed a pure testicular teratoma. Noncirrhotic left portal hypertension with bleeding from an isolated gastric varix secondary to metastasic testicular cancer has not been described before. Clinicians must consider the possibility of malignancy in the differential diagnosis of a young man presenting with unexplained gastrointestinal bleeding.

Metabolically inactive insulin analogue does not prevent autoimmune diabetes in NOD mice.

AIMS/HYPOTHESIS: Insulin is widely considered to be a driver antigen in type 1 diabetes in humans and in mouse models of the disease. Therefore, insulin or insulin analogues are candidates for tolerogenic drugs to prevent disease onset in individuals with risk of diabetes. Previous experiments have shown that autoimmune diabetes can be prevented in NOD mice by repeated doses of insulin administered via an oral, nasal or parenteral route, but clinical trials in humans have not succeeded. The hypoglycaemic activity of insulin is dose-limiting in clinical studies attempting tolerance and disease prevention. Here, we aimed to investigate the therapeutic potential of metabolically inactive insulin analogue (MII) in NOD mice. METHODS: The tolerogenic potential of MII to prevent autoimmune diabetes was studied by administering multiple i.v. or s.c. injections of MII to non-diabetic 7-12-week-old female NOD mice in three geographical colony locations. The incidence of diabetes was assessed from daily or weekly blood glucose measurements. The effect of MII on insulin autoantibody levels was studied using an electrochemiluminescence-based insulin autoantibody assay. The effect on the number of insulin-reactive CD8+ and CD4+ T lymphocytes in peripheral lymphoid tissue was studied with MHC class I and MHC class II tetramers, respectively. RESULTS: We found that twice-weekly s.c. administration of MII accelerates rather than prevents diabetes. High-dose i.v. treatment did not prevent disease or affect insulin autoantibody levels, but it increased the amount of insulin-reactive CD4+ T lymphocytes in peripheral lymphoid tissue. CONCLUSIONS/INTERPRETATION: Our data suggest that parenteral MII, even when used in high doses, has little or no therapeutic potential in NOD mice and may exacerbate disease.

Pulmonary endarterectomy outputs in chronic thromboembolic pulmonary hypertension. / Resultados de la tromboendarterectomía pulmonar en la hipertensión pulmonar tromboembólica crónica.

BACKGROUND AND OBJECTIVE: Pulmonary thromboendarterectomy surgery is the treatment of choice for patients with chronic thromboembolic pulmonary hypertension; extremely high pulmonary vascular resistance constitutes a risk factor for hospital mortality. The objective of this study was to analyze the immediate and long-term results of the surgical treatment of chronic thromboembolic pulmonary hypertension in patients with very severe pulmonary hypertension. MATERIAL AND METHODS: Since February 1996, we performed 160 pulmonary thromboendarterectomies. We divided the patient population in 2 groups: group 1, which included 40 patients with pulmonary vascular resistance≥1090dyn/sec/cm-5, and group 2, which included the remaining 120 patients. RESULTS: Hospital mortality (15 vs. 2.5%), reperfusion pulmonary edema (33 vs. 14%) and heart failure (23 vs. 3.3%) were all higher in group 1; however, after one year of follow-up, there were no significant differences in the clinical, hemodynamic and echocardiographic conditions of both groups. Survival rate after 5 years was 77% in group 1 and 92% in group 2 (P=.033). After the learning curve including the 46 first patients, there was no difference in hospital mortality (3.8 vs. 2.3%) or survival rate after 5 years (96.2% in group 1 and 96.2% in group 2). CONCLUSIONS: Pulmonary thromboendarterectomy is linked to significantly higher morbidity and mortality rates in patients with severe chronic thromboembolic pulmonary hypertension. Nevertheless, these patients benefit the same from the procedure in the mid-/long-term. In our experience, after the learning curve, this surgery is safe in severe pulmonary hypertension and no level of pulmonary vascular resistance should be an absolute counter-indication for this surgery.

'Jamaican Stone': A potentially lethal remedy for delaying ejaculation.

Poisoning by ingestion of 'Jamaican Stone', a kind of cardioactive steroid, is extremely rare. However, mortality is very high. For this reason, when it occurs, an early and accurate diagnosis represents a critical challenge for clinicians. We present an unusual case of electrical storm caused by this substance.

Veno-arterial ECMO for rescue of severe airway hemorrhage with rigid bronchoscopy after pulmonary artery thromboendarterectomy.

Pulmonary endarterectomy (PEA) is the treatment of choice to relieve pulmonary artery obstruction in patients with chronic thromboembolic pulmonary hypertension (CTEPH). We present a patient with airway obstruction and acute respiratory failure due to large blood clots obstructing the trachea and main left bronchus. This condition was accompanied by right ventricle failure and cardiogenic shock. A venoarterial ECMO system was used for cardiopulmonary support before extracting the clots and clearing the airway by rigid bronchoscopy.

Evaluation of right ventricular function after cardiac surgery: The importance of tricuspid annular plane systolic excursion and right ventricular ejection fraction.

OBJECTIVE: The evaluation of right ventricular systolic function is essential to the hemodynamic management of critically ill cardiac patients. Nevertheless, assessment of right ventricular function remains problematic. We sought to analyze the correlation between tricuspid annular plane systolic excursion (TAPSE) and right ventricular ejection fraction (RVEF) in the assessment of global and regional right ventricular function, respectively. METHODS: This was a prospective study of 61 cardiac surgical patients. TAPSE was measured with transthoracic echocardiography and RVEF was obtained by a thermodilution pulmonary artery catheter. Both measurements were estimated simultaneously during the early postoperative period. Patients with previously identified severe tricuspid insufficiency were excluded from the study to avoid confounding results. RESULTS: The etiologies for cardiac surgery were surgical pulmonary thromboendarterectomy in 19 patients, valve replacement in 17 patients, heart transplant in 13 patients, and coronary artery bypass graft in 9 patients. Mean RVEF and TAPSE were 26.2% ± 9.7% and 11.4 ± 4 mm, respectively. RVEF and TAPSE showed a significant correlation (r = 0.73, P < .001). Weak reverse relationships between TAPSE or RVEF with afterload hemodynamic parameters, mean pulmonary artery pressure, or pulmonary vascular resistance were elucidated. CONCLUSIONS: TAPSE is a robust measure of right ventricular function that correlates with RVEF assessed by pulmonary artery catheter. A noninvasive method such as echocardiography can guide and support invasive monitoring of right ventricular function in cardiac surgical patients.

Oral insulin (human, murine, or porcine) does not prevent diabetes in the non-obese diabetic mouse.

Studies have shown oral insulin prevents type 1 diabetes (T1D) in mouse models, however human trials were inconclusive. We tested the ability of different insulins to prevent T1D in non-obese diabetic mice. Mice received oral insulin or PBS twice weekly and disease was monitored. Contrary to previous studies, no insulin tested showed significant ability to prevent T1D, nor did testing of linked suppression in a delayed type hypersensitivity model have reproducible effect. To investigate delivery of antigen within the GI tract, blue dye was fed to mice. Dye traveled 5-8 cm from stomach to small intestine within 10s, suggesting orally administered antigen may not get digested in the stomach in mice. Insulin incubated with jejunum extracts was instantly digested. Thus, in humans large doses of insulin may be required to achieve tolerance as antigen may be more vulnerable to digestion in the stomach even before reaching the small intestine.

Invariant NKT cells require autophagy to coordinate proliferation and survival signals during differentiation.

Autophagy regulates cell differentiation, proliferation, and survival in multiple cell types, including cells of the immune system. In this study, we examined the effects of a disruption of autophagy on the differentiation of invariant NKT (iNKT) cells. Using mice with a T lymphocyte-specific deletion of Atg5 or Atg7, two members of the macroautophagic pathway, we observed a profound decrease in the iNKT cell population. The deficit is cell-autonomous, and it acts predominantly to reduce the number of mature cells, as well as the function of peripheral iNKT cells. In the absence of autophagy, there is reduced progression of iNKT cells in the thymus through the cell cycle, as well as increased apoptosis of these cells. Importantly, the reduction in Th1-biased iNKT cells is most pronounced, leading to a selective reduction in iNKT cell-derived IFN-γ. Our findings highlight the unique metabolic and genetic requirements for the differentiation of iNKT cells.

Pulmonary thromboendarterectomy in 106 patients with chronic thromboembolic pulmonary hypertension.

INTRODUCTION: Pulmonary thromboendarterectomy is the treatment of choice in chronic thromboembolic pulmonary hypertension. We report our experience with this technique. METHODS: Between February 1996 and June 2014, we performed 106 pulmonary thromboendarterectomies. Patient population, morbidity and mortality and the long-term results of this technique (survival, functional improvement and resolution of pulmonary hypertension) are described. RESULTS: Subjects' mean age was 53±14 years. A total of 89% were WHO functional class III-IV, presurgery mean pulmonary pressure was 49±13mmHg and mean pulmonary vascular resistance was 831±364 dynes.s.cm(-5). In-hospital mortality was 6.6%. The most important post-operative morbidity was reperfusion pulmonary injury, in 20% of patients; this was an independent risk factor (p=0.015) for hospital mortality. With a 31-month median follow-up (interquartile range: 50), 3- and 5-year survival was 90 and 84%. At 1 year, 91% were WHO functional class I-II; mean pulmonary pressure (27±11mmHg) and pulmonary vascular resistance (275±218 dynes.s.cm(-5)) were significantly lower (p<0.05) than before the intervention. Although residual pulmonary hypertension was detected in 14 patients, their survival at 3 and 5 years was 91 and 73%, respectively. CONCLUSIONS: Pulmonary thromboendarterectomy offers excellent results in chronic thromboembolic pulmonary hypertension. Long-term survival is good, functional capacity improves, and pulmonary hypertension is resolved in most patients.

Antigen-Specific Regulatory T Cells and Low Dose of IL-2 in Treatment of Type 1 Diabetes.

Regulatory T cells (Tregs) play an important role in preventing effector T-cell (Teff) targeting of self-antigens that can lead to tissue destruction in autoimmune settings, including type 1 diabetes (T1D). Autoimmunity is caused in part by an imbalance between Teff and Tregs. Early attempts to treat with immunosuppressive agents have led to serious side effects, thus requiring a more targeted approach. Low-dose IL-2 (LD IL-2) can provide immunoregulation with few side effects by preferentially acting on Tregs to drive tolerance. The concept of LD IL-2 as a therapeutic approach is supported by data in mouse models where autoimmunity is cured and further strengthened by success in human clinical studies in hepatitis C virus-induced vasculitis, chronic graft-versus-host disease, and Alopecia areata. Treatment will require identification of a safe therapeutic window, which is a difficult task given that patients are reported to have deficient or defective IL-2 production or signaling and have experienced mild activation of NK cells and eosinophils with LD IL-2 therapy. In T1D, an LD IL-2 clinical trial concluded that Tregs can be safely expanded in humans; however, the study was not designed to address efficacy. Antigen-specific therapies have also aimed at regulation of the autoimmune response but have been filled with disappointment despite an extensive list of diverse islet antigens tested in humans. This approach could be enhanced through the addition of LD IL-2 to the antigenic treatment regimen to improve the frequency and function of antigen-specific Tregs, without global immunosuppression. Here, we will discuss the use of LD IL-2 and islet antigen to enhance antigen-specific Tregs in T1D and focus on what is known about their immunological impact, their safety, and potential efficacy, and need for better methods to identify therapeutic effectiveness.