Pre-transplant antibody screening and anti-CD154 costimulation blockade promote long-term xenograft survival in a pig-to-primate kidney transplant model.

Xenotransplantation has the potential to alleviate the organ shortage that prevents many patients with end-stage renal disease from enjoying the benefits of kidney transplantation. Despite significant advances in other models, pig-to-primate kidney xenotransplantation has met limited success. Preformed anti-pig antibodies are an important component of the xenogeneic immune response. To address this, we screened a cohort of 34 rhesus macaques for anti-pig antibody levels. We then selected animals with both low and high titers of anti-pig antibodies to proceed with kidney transplant from galactose-α1,3-galactose knockout/CD55 transgenic pig donors. All animals received T-cell depletion followed by maintenance therapy with costimulation blockade (either anti-CD154 mAb or belatacept), mycophenolate mofetil, and steroid. The animal with the high titer of anti-pig antibody rejected the kidney xenograft within the first week. Low-titer animals treated with anti-CD154 antibody, but not belatacept exhibited prolonged kidney xenograft survival (>133 and >126 vs. 14 and 21 days, respectively). Long-term surviving animals treated with the anti-CD154-based regimen continue to have normal kidney function and preserved renal architecture without evidence of rejection on biopsies sampled at day 100. This description of the longest reported survival of pig-to-non-human primate kidney xenotransplantation, now >125 days, provides promise for further study and potential clinical translation.

Non-invasive early detection of acute transplant rejection via nanosensors of granzyme B activity.

The early detection of the onset of transplant rejection is critical for the long-term survival of patients. The diagnostic gold standard for detecting transplant rejection involves a core biopsy, which is invasive, has limited predictive power and carries a morbidity risk. Here, we show that nanoparticles conjugated with a peptide substrate specific for the serine protease granzyme B, which is produced by recipient T cells during the onset of acute cellular rejection, can serve as a non-invasive biomarker of early rejection. When administered systemically in mouse models of skin graft rejection, these nanosensors preferentially accumulate in allograft tissue, where they are cleaved by granzyme B, releasing a fluorescent reporter that filters into the recipient's urine. Urinalysis then discriminates the onset of rejection with high sensitivity and specificity before features of rejection are apparent in grafted tissues. Moreover, in mice treated with subtherapeutic levels of immunosuppressive drugs, the reporter signals in urine can be detected before graft failure. This method may enable routine monitoring of allograft status without the need for biopsies.

Safety and tolerability of denufosol tetrasodium inhalation solution, a novel P2Y2 receptor agonist: results of a phase 1/phase 2 multicenter study in mild to moderate cystic fibrosis.

Denufosol tetrasodium (INS37217) is a selective P2Y(2) agonist that stimulates ciliary beat frequency and Cl(-) secretion in normal and cystic fibrosis (CF) airway epithelia, and is being investigated as an inhaled treatment for CF. The Cl(-) secretory response is mediated via a non-CFTR pathway, and the driving force for Cl(-) secretion is enhanced by the effect of P2Y(2) activation to also inhibit epithelial Na(+) transport. Denufosol is metabolically more stable and better tolerated, and may enhance mucociliary clearance for a longer period of time than previously investigated P2Y(2) agonists. The goal of this phase 1/phase 2 study was to assess the safety and tolerability of single and repeated doses of aerosolized denufosol in subjects with CF. The study was a double-blind, placebo-controlled, multicenter comparison of ascending single doses of denufosol (10, 20, 40, and 60 mg, administered by inhalation via the Pari LC Star nebulizer) vs. placebo (normal saline), followed by a comparison of twice-daily administration of the maximum tolerated dose (MTD) of denufosol or placebo for 5 days. Thirty-seven adult (18 years of age or older) and 24 pediatric (5-17 years of age) subjects with CF were evaluated in five cohorts. Subjects were randomized in a 3:1 ratio to receive either denufosol or placebo within each cohort. The percent of subjects experiencing adverse events was similar between the denufosol and placebo groups. The most common adverse event in subjects receiving denufosol was chest tightness in adult subjects (39%) and cough in pediatric subjects (56%). Three (7%) subjects receiving denufosol and one (7%) subject receiving placebo experienced a serious adverse event. Forced expiratory volume in 1 sec (FEV(1)) profiles following dosing were similar across treatment groups, with some acute, reversible decline seen in both groups, most notably in subjects with lower lung function at baseline. In conclusion, doses up to 60 mg of denufosol inhalation solution were well-tolerated in most subjects. Some intolerability was noted among subjects with lower baseline lung function. Based on the results of this phase 1/phase 2 study, the Therapeutics Development Network (TDN) of the Cystic Fibrosis Foundation (CFF) and Inspire Pharmaceuticals, Inc., recently completed a multicenter, 28-day, phase 2 safety and efficacy clinical trial of denufosol inhalation solution in CF subjects with mild lung disease.

Inhaled P2Y2 receptor agonists as a treatment for patients with Cystic Fibrosis lung disease.

P2Y(2) receptor agonists are a new class of compounds that are being evaluated as a treatment for the pulmonary manifestations of Cystic Fibrosis (CF). Results of preclinical research suggest that these compounds inhibit sodium absorption, restore chloride conductance and rehydrate the CF airway surface. In addition, P2Y(2) receptor agonists have been shown to enhance ciliary beat frequency and increase mucociliary clearance in animals and subjects with impaired mucociliary clearance. The normalization of airway surface liquid and enhancement of lung clearance is expected to provide a clinical benefit to CF patients. A number of P2Y(2) agonist compounds have been evaluated in healthy subjects and patients with CF. Most recently, INS37217, a metabolically stable and potent P2Y(2) agonist has been developed and studies have shown it to be well-tolerated when given via inhalation. This compound is currently being evaluated in children and adults with CF lung disease.

Perceptions of intimate partner violence: a cross sectional survey of surgical residents and medical students.

BACKGROUND: Intimate partner violence (IPV) is an important health issue. Many medical students and residents have received training relating to IPV, but previous studies show that many students feel that their training has been inadequate. Our objective was to assess the knowledge, attitudes and perceptions about IPV among university medical students and surgical residents. METHODS: We administered an online survey to a sample of Ontario medical students and surgical residents. The survey instrument was a modified version of the Provider Survey. RESULTS: Two hundred medical students and surgical residents participated in the survey (response rate: 29%). Misperceptions about IPV among respondents included the following: 1) victims must get something from the abusive relationships (18.2%), 2) physicians should not interfere with a couple's conflicts (21%), 3) asking about IPV risks offending patients (45%), 4) Victims choose to be victims (11.1%), 5) it usually takes 'two to tango' (18.3%), and 6) some patients' personalities cause them to be abused (41.1%). The majority of respondents (75.0%) believed identifying IPV was very relevant to clinical practice. The majority of medical students (91.2%) and surgical residents (96.9%) estimated the IPV prevalence in their intended practice to be 10% or less. Most of the medical students (84%) and surgical residents (60%) felt that their level of training on IPV was inadequate and over three quarters of respondents (77.2%) expressed a desire to receive additional education and training on IPV. CONCLUSIONS: There are misconceptions among Canadian medical students and surgical residents about intimate partner violence. These misconceptions may stem from lack of education and personal discomfort with the issue or from other factors such as gender. Curricula in medical schools and surgical training programs should appropriately emphasize educational opportunities in the area of IPV. © 2013 KUMS, All rights reserved.

Phase 2 randomized safety and efficacy trial of nebulized denufosol tetrasodium in cystic fibrosis.

RATIONALE: Denufosol tetrasodium is a selective P2Y(2) agonist that enhances mucosal hydration and mucus clearance by activating Cl(-) secretion and inhibiting epithelial Na(+) transport through a non-cystic fibrosis transmembrane conductance regulator mechanism in the lung. OBJECTIVES: To examine the safety and efficacy of 28 days of treatment with denufosol compared with placebo in patients with mild cystic fibrosis. METHODS: The study was a randomized, double-blind, multi-center, 28-day, phase 2 clinical trial of denufosol tetrasodium inhalation solution (20, 40, or 60 mg) versus placebo (normal saline). Patients with screening FEV(1) >or= 75% of predicted normal value and not treated with inhaled antibiotics for the past 30 days were randomized to receive one of three doses of denufosol or placebo administered three times daily. MEASUREMENTS AND MAIN RESULTS: Eighty-nine patients were randomized and received the study drug, 94% completed the study, and 98% were compliant with dosing. All treatments were generally well tolerated, with no dose-response trends observed with respect to safety parameters. The most common adverse event was cough (52% of placebo patients and 47% of denufosol patients). Five patients discontinued early due to adverse events, two on placebo and three on denufosol. Denufosol patients (pooling active doses) had significantly higher changes from baseline in FEV(1) (P = 0.006), FEF(25%-75%) (P = 0.008), FVC (P = 0.022), and FEV(1)/FVC (P = 0.047) than placebo patients at the end of the study. CONCLUSIONS: Denufosol administered three times daily for 28 days appeared to be safe and well tolerated in this population with mild cystic fibrosis and provided preliminary evidence of potential benefit in lung function.