Nucleotide regulation of goblet cells in human airway epithelial explants: normal exocytosis in cystic fibrosis

The regulation of mucin secretion by airway goblet cells is poorly understood and the receptor-based regulatory mechanisms have not been described in human airways. In the present study, we report that extracellular triphosphate nucleotides regulate the rate of granule release from goblet cells in both normal and cystic fibrosis (CF) airway epithelial explants. Explants isolated from nasal and tracheobronchial tissues were mounted in perfusion chambers and the secretory activity was assessed by videomicroscopic determination of degranulation in single goblet cells and by ELISA determination of mucins secreted into the mucosal perfusate. Baseline degranulation was measured at 0.05 degranulation events (DE)/min. In normal goblet cells, mucosal ATP (10(-4) M, n = 17) induced a biphasic secretory response comprising 29.1 +/- 4.9 DE during the first 5 min, with an initial rate of 118.2 +/- 10.2 DE/min. Mucosal UTP (10(-4) M, n = 9) induced a similar response to ATP (initial rate: 89.2 +/- 23.9 DE/min, 17.9 +/- 5.1 DE in 5 min), but mucosal 2-MeSATP was not an effective agonist (initial rate: 1.5 +/- 1.4 DE/min, 2.3 +/- 0.5 DE in 5 min). Determination of mucins by ELISA confirmed that both ATP and UTP induced similar secretory responses but that 2-MeSATP was not effective. In CF explants, mucosal UTP (10(-4) M, n = 6) induced similar responses to those observed in normal tissues (initial rate: 82.5 +/- 27.5 DE/min, 18.8 +/- 4.1 DE in 5 min). We conclude that human nasal and tracheobronchial goblet cells are stimulated by mucosal nucleotides, probably via a 5'-nucleotide receptor, and that this response is unaffected by CF.

MALDI Matrices for Biomolecular Analysis Based on Functionalized Carbon Nanomaterials

When used in small molar ratios of matrix to analyte, derivatized fullerenes and single wall nanotubes are shown to be efficient matrices for matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. The mixing of an acidic functionalized fullerene with a solution of bioanalyte, depositing a dried droplet, and irradiating with a pulsed nitrogen laser yields protonated or cationized molecular ions. Derivatized fullerenes could offer several advantages over conventional MALDI matrices: a high analyte ionization efficiency, a small molar ratios (less than 1) of matrix/analyte, and a broader optical absorption spectrum, which should obviate specific wavelength lasers for MALDI acquisitions. The major disadvantage to the use of fullerenes is the isobaric interference between matrix and analyte ions; however, it is overcome by using MALDI-ion mobility time-of-flight (IM-oTOF) mass spectrometry to preseparate carbon cluster ions from bioanalyte ions prior to TOF mass analysis. However, an alternative to the dried droplet preparation of fullerene MALDI samples is the aerosolization of matrix-analyte solutions (or slurries) followed by impacting the aerosol onto a stainless surface. We also demonstrate that the fullerene matrices can be used to acquire spectra from rat brain tissue.

Quality of life in patients awaiting lung transplant: cystic fibrosis versus other end-stage lung diseases

The symptoms associated with chronic lung disease can impair quality of life and psychosocial functioning. The purpose of the present study was to provide a thorough baseline assessment of quality of life in patients with end-stage lung disease and being evaluated for transplant; and to assess potential differences in quality of life between patients with cystic fibrosis (CF) and those with other types of end-stage lung disease (e.g., chronic obstructive pulmonary disease (COPD), interstitial pulmonary fibrosis (IPF)). We evaluated 58 patients with CF and 52 patients with other types of end-stage lung disease who were recruited for this study during an assessment of their candidacy for lung transplant. Subjects completed a battery of questionnaires that assessed demographic factors (including work and educational status), the presence of psychological distress (anxiety and depression), availability of social support, coping styles, and physical functioning. Despite significant impairment in physical functioning in the areas of recreation, household activities, sleep, and ambulation, other indices of life quality suggested good adaptation in the majority of patients. Also, quality of life differed for patients with CF and for those with other types of end-stage lung disease. Patients with CF were more likely to be working, had lower levels of anxiety and higher levels of social support, and used more functional coping strategies than did patients with other end-stage lung disease. These results highlight the fact that patients with different types of lung disease may require different psychosocial services as they await transplant. These findings also raise the question of whether there is a difference in quality of life after transplant between patients with CF and those with other types of lung disease.

Matrix Implanted Laser Desorption Ionization (MILDI) Combined with Ion Mobility-Mass Spectrometry for Bio-Surface Analysis

The implantation of low velocity massive gold cluster ions allows homogeneous incorporation of a metallic matrix into the near-surface region of rat brain tissues. Subsequent analysis by laser desorption ionization mass spectrometry yields spectra exhibiting molecular ion peaks in the mass range up to 35 kDa similar to those observed by matrix-assisted LDI. Matrix-implanted LDI when combined with ion-mobility preseparation promises to be a useful technique for molecular imaging of biotissues with a laser microprobe.

Sleep in Pierre Robin syndrome

Eight patients (aged 8 to 22 years) with the Pierre Robin syndrome underwent sleep studies. Seven demonstrated significant although minor degrees of increased sleep disturbances and apneas, and less time spent in the rapid-eye-movement (REM) stage of sleep. One patient who had previously undergone mandibular corrective surgery had major sleep abnormalities (central apnea index of 81.7 although an obstructive sleep apnea index of only 1.9). The patients had small mandibles, as demonstrated by lateral cephalometric roentgenography, and mildly increased right ventricular diastolic dimensions, as shown by M-mode echocardiography. Snoring was present in all of these patients and in 13 of 22 patients questioned from our Pierre Robin clinic. We conclude that minor abnormalities in sleep, mandibular size, and right ventricular size persist well into adolescence in the majority of patients with Pierre Robin syndrome. These appear to be clinically insignificant; however, a small percentage of such patients may continue to have major sleep disturbances.

Experimental en bloc double-lung transplantation

A technique of en bloc double-lung transplantation through a median sternotomy has been developed. Hypothermic circulatory arrest was used after surface cooling in 7 puppies (mean weight, 3.1 kg; range, 1.5 to 4.1 kg). A double lung block, consisting of the two lungs, distal trachea, the main pulmonary artery, and a large cuff of left atrium, was removed from weight-matched donors. After the arrest of the circulation by inflow occlusion, bilateral pneumonectomies were performed in the recipient. The donor double-lung block was then implanted with anastomoses at the distal trachea, the posterior left atrium, and the main pulmonary artery. All animals were successfully rewarmed and had excellent hemodynamic function and gas exchange for periods of up to 24 hours. If primate experiments with long-term survival confirm these initial results, this procedure may have a role in the treatment of patients with end-stage respiratory disease but acceptable cardiac function.

Acute occupational exposure to antineoplastic agents

Antineoplastic agents may exhibit effects not only in patients therapeutically exposed, but also in health workers who prepare and administer these drugs. Concern to date has focused on long-term health consequences, including adverse reproductive outcomes, altered immunity, and increased cancer risk. The burgeoning use of these drugs for non-malignant illnesses has enlarged the health worker population at risk beyond oncology personnel to include professionals in immunology, rheumatology, nephrology, and dermatology. We report here two cases of hospital workers who experienced acute adverse health effects resulting from occupational exposure to antineoplastic drugs. We believe such acute events are under-reported, and that they demonstrate the need for physician awareness regarding their management.

In vivo regulation of von willebrand factor synthesis: von Willebrand factor production in endothelial cells after lung transplantation between normal pigs and von Willebrand factor-deficient pigs

To evaluate the regulation of plasma von Willebrand factor (vWF) and its in situ production by endothelial cells (ECs), 12 swine leukocyte antigen (SLA)-compatible left lung transplantations were performed. Normal lungs were transplanted into 10 pigs homozygous for von Willebrand disease and into 2 normal pigs. Additionally, 1 normal pig underwent pneumonectomy, and 1 SLA-incompatible lung transplantation between normal pigs was performed. None of the transplanted animals received immunosuppressive therapy. Plasma vWF level was evaluated by ELISA and multimeric pattern. EC vWF content was assessed by immunohistochemistry. Global hemostasis was assessed by standardized ear bleeding time. Six of 12 SLA-compatible lung transplantations and the incompatible transplantation were successful and were used for the study. The functions and the viability of ECs, reflected by their ability to produce vWF and normal multimeric plasma vWF pattern, were preserved in SLA-compatible and -incompatible lung transplantations. vWF production was preserved in ECs that initially synthesized it. EC constitutive and storage pathways are modulated differently according to transplantation compatibility and severity of rejection. In SLA-compatible lung transplantations without histological evidence of rejection, the production of vWF was preserved, whereas constitutive vWF secretion appeared to be altered in cases with minor histological signs of rejection. In pigs with von Willebrand disease that were transplanted with normal lungs without sign of rejection, plasma vWF was significantly increased in an amount expected from the estimated production of a normal lung. In the transplanted normal lung, there was no vWF overexpression by the ECs and no recruitment of ECs that initially did not express vWF. In SLA-incompatible transplantation, ECs were morphologically normal with increased and blurred vWF labeling, whereas plasma vWF levels remained normal, reflecting that EC activation is associated with an increased vWF production with probable diversion to storage pathway. This model depicts the changes of EC regulation of vWF secretion in pig lung transplants. However, this model cannot be directly extrapolated to human organ transplantation because animals did not receive any immunosuppressive therapy, which may be toxic to ECs.

Closing the access barrier for effective anti-malarials in the private sector in rural Uganda: consortium for ACT private sector subsidy (CAPSS) pilot study

Background

Artemisinin-based combination therapy (ACT), the treatment of choice for uncomplicated falciparum malaria, is unaffordable and generally inaccessible in the private sector, the first port of call for most malaria treatment across rural Africa. Between August 2007 and May 2010, the Uganda Ministry of Health and the Medicines for Malaria Venture conducted the Consortium for ACT Private Sector Subsidy (CAPSS) pilot study to test whether access to ACT in the private sector could be improved through the provision of a high level supply chain subsidy.

Methods

Four intervention districts were purposefully selected to receive branded subsidized medicines - “ACT with a leaf”, while the fifth district acted as the control. Baseline and evaluation outlet exit surveys and retail audits were conducted at licensed and unlicensed drug outlets in the intervention and control districts. A survey-adjusted, multivariate logistic regression model was used to analyse the intervention’s impact on: ACT uptake and price; purchase of ACT within 24 hours of symptom onset; ACT availability and displacement of sub-optimal anti-malarial.

Results

At baseline, ACT accounted for less than 1% of anti-malarials purchased from licensed drug shops for children less than five years old. However, at evaluation, “ACT with a leaf” accounted for 69% of anti-malarial purchased in the interventions districts. Purchase of ACT within 24 hours of symptom onset for children under five years rose from 0.8% at baseline to 26.2% (95% CI: 23.2-29.2%) at evaluation in the intervention districts. In the control district, it rose modestly from 1.8% to 5.6% (95% CI: 4.0-7.3%). The odds of purchasing ACT within 24 hours in the intervention districts compared to the control was 0.46 (95% CI: 0.08-2.68, p=0.4) at baseline and significant increased to 6.11 (95% CI: 4.32-8.62, p<0.0001) at evaluation. Children less than five years of age had “ACT with a leaf” purchased for them more often than those aged above five years. There was no evidence of price gouging.

Conclusions

These data demonstrate that a supply-side subsidy and an intensive communications campaign significantly increased the uptake and use of ACT in the private sector in Uganda.

Tobacco and alcohol use in lung transplant candidates and recipients

Tobacco and alcohol use among lung transplant candidates and recipients is unknown. Our first goal was to describe tobacco and alcohol use before and after lung transplant in patients with cystic fibrosis (CF) and other pulmonary diseases (non-CF). Our second goal was to determine whether demographic variables, depression, anxiety and social support predicted tobacco and alcohol use. Self-report data from transplant candidates and recipients, and transplant nurse coordinator ratings of post-transplant smoking and drinking were utilized. Data from two samples were analyzed. Sample 1 comprised 219 patients being evaluated for lung transplant, and sample 2 comprised 45 transplant recipients who were 1-7 yrs post-transplant. The results from analyzing sample 1 indicated that 72% of non-CF patients and 16% of CF patients had a history of smoking cigarettes, and the majority of patients in both groups had consumed alcohol in the past. For CF patients, past smoking was related to higher depression scores, and past drinking was related to higher education and lower social support. For non-CF patients, a history of smoking was associated with being Caucasian and older. For CF patients, a history of drinking was associated with being older and less depressed, and for non-CF patients a history of drinking was associated with higher education and lower social support. Post-transplant 100% of recipients reported abstinence from tobacco, and over 60% reported abstinence from alcohol. Transplant coordinator ratings corroborated that no transplant recipients were using tobacco products or consuming alcohol in an excessive or problematic manner. For both groups, consuming alcohol after transplant was related to lower levels of social support. In conclusion, lung recipients remain abstinent from tobacco, and although over 30% of patients consume alcohol after transplant, it is not at problematic levels. Smoking and drinking behaviors were related to demographic variables, depression, and low social support.

Determination of ionised calcium by ion selective electrode is not independent of albumin concentration

The relationship of ionised calcium measurement to changes in serum total protein and albumin were studied both in vivo and in vitro. During venostasis serum ionised calcium was determined in 10 control subjects using an Orion SS20 analyser. A slight but significant increase in ionised calcium occurred only after prolonged venostasis (15 min), when gross changes in total protein and albumin were seen. The effect of albumin concentration on serum ionised calcium was studied in vitro by the dialysis technique of Payne. The increase in ionised calcium in 40 sera was 0.0198 mmol/l per 10 g albumin change. We conclude that albumin-related variation in serum ionised calcium determination required such gross changes that correction is rarely necessary in clinical practice. When gross albumin alteration occurs, the appropriate correction for the analyser used should be determined and applied.

Combination therapy with diltiazem and propranolol: precipitation of congestive heart failure

Although congestive heart failure has been reported with the combination of a beta blocker and either verapamil or nifedipine, it has not previously been reported for combination therapy that includes diltiazem. The following case documents the occurrence of clinical congestive failure in a patient with baseline left ventricular dysfunction and severe angina pectoris. Although the patients had tolerated propranolol therapy for years without difficulty, and high-dose diltiazem monotherapy with an excellent clinical response, the combination of diltiazem and propranolol resulted in the development of congestive heart failure. Thus, although generally well tolerated, given the suitable scenario of reduced left ventricular function, the combination of diltiazem and a beta blocker may adversely affect left ventricular performance.

Antiplasmodial activity, in vivo pharmacokinetics and anti-malarial efficacy evaluation of hydroxypyridinone hybrids in a mouse model

Background

During the erythrocytic stage in humans, malaria parasites digest haemoglobin of the host cell, and the toxic haem moiety crystallizes into haemozoin. Chloroquine acts by forming toxic complexes with haem molecules and interfering with their crystallization. In chloroquine-resistant strains, the drug is excluded from the site of action, which causes the parasites to accumulate less chloroquine in their acid food vacuoles than chloroquine-sensitive parasites. 3-Hydroxylpyridin-4-ones are known to chelate iron; hydroxypyridone-chloroquine (HPO-CQ) hybrids were synthesized in order to determine whether they can inhibit parasites proliferation in the parasitic digestive vacuole by withholding iron from plasmodial parasite metabolic pathway.

Methods

Two HPO-CQ hybrids were tested against Plasmodium falciparum chloroquine-sensitive (D10 and 3D7) and -resistant strains (Dd2 and K1). The pharmacokinetic properties of active compounds were determined using a mouse model and blood samples were collected at different time intervals and analysed using LC–MS/MS. For in vivo efficacy the mice were infected with Plasmodium berghei in a 4-day Peters’ test. The parasitaemia was determined from day 3 and the course of the infection was followed by microscopic examination of stained blood films every 2–3 days until a rise in parasitaemia was observed in all test subjects.

Results

IC₅₀ values of the two compounds for sensitive and resistant strains were 0.064 and 0.047 µM (compound 1), 0.041 and 0.122 µM (compound 2) and 0.505 and 0.463 µM (compound 1), 0.089 and 0.076 µM (compound 2), respectively. Pharmacokinetic evaluation of these compounds showed low oral bioavailability and this affected in vivo efficacy when compounds were dosed orally. However, when dosed intravenously compound 1 showed a clearance rate of 28 ml/min/kg, an apparent volume of distribution of 20 l/kg and a half-life of 4.3 h. A reduction in parasitaemia was observed when compound 1 was dosed intravenously for four consecutive days in P. berghei-infected mice. However, a rise in parasitaemia levels was observed on day 6 and on day 9 for chloroquine-treated mice.

Conclusion

The hybrid compounds that were tested were able to reduce parasitaemia levels in P. berghei-infected mice when dosed intravenously, but parasites recrudesced 24 h after the administration of the least dose. Despite low oral bioavailability, the IV data obtained suggests that further structural modifications may lead to the identification of more HPO-CQ hybrids with improved pharmacokinetic properties and in vivo efficacy.

Abstract 2276: Preclinical development and mechanism of action studies of NM21-1480, a PD-L1/4-1BB/HSA trispecific MATCH3 therapeutic clinical candidate

Antagonistic molecules targeting the PD-1/PD-L1 axis have shown excellent activity in the clinic. However the majority of patients do not respond to the therapy due to multifaceted reasons implicating a non-effective activation of the immune system in those patients. The co-stimulatory molecule 4-1BB has been shown to be a key signalling component of T cells and the combination of 4-1BB activation and PD-1/PD-L1 antagonism has been shown to be highly active in preclinical models. Systemic application of first generation anti-4-1BB antibodies however have resulted in dose limiting hepatic toxicities. We have generated a novel 4-1BB/PD-L1/HSA trispecific MATCH3 immunomodulatory drug candidate (NM21-1480) that agonizes 4-1BB conditionally upon PD-L1 binding / blockade. Here we show the preclinical development data package for NM21-1480 demonstrating exquisite tumour-specific T cell activation associated with both 4-1BB agonism as well as PD-L1/PD-1 antagonism. We also demonstrate tumour specific localisation and accumulation of NM21-1480 in a mouse xenograft model. We report on the toxicity profile and pharmacokinetic properties of the molecule in non-human primates. We plan to initiate a first-in-human clinical study in the second half of 2020 to determine the safety, tolerability and first signs of clinical activity of the molecule.

Citation Format: Daniel Snell, Tea Gunde, Stefan Warmuth, Peter Lichtlen, Julia Tietz, Matthias Brock, Alexandre Simonin, Christian Hess, Weinert Christopher, Robin Heiz, Naomi Flueckiger, Julia Zeberer, Dania Diem, Dana Mahler, Diego Morenzoni, Belinda Wickihalder, Simone Muntwiler, Antonia Poelderl, Benjamin Kuettner, Sandro Wagen, Sebastian Meyer, Timothy Egan, David Urech. Preclinical development and mechanism of action studies of NM21-1480, a PD-L1/4-1BB/HSA trispecific MATCH3 therapeutic clinical candidate [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2276.

Abstract 1532: A novel, monovalent tri-specific antibody-based molecule that simultaneously modulates PD-L1 and 4-1BB exhibits potent anti-tumoral activity in vivo

The combined immunomodulation of PD-L1/PD-1 and 4-1BB is considered a promising strategy to increase response rates among cancer patients who are eligible to receive PD-L1/PD-1 inhibitors. Unfortunately, encouraging pre-clinical results achieved with such regimens have not yet translated into durable clinical success, due to addition of 4-1BB-agonistic antibodies being either intolerable at effective doses or ineffective, despite tolerability, at all doses. To eliminate this safety/efficacy tradeoff, we engineered a novel, tri-specific immunomodulatory drug candidate. The molecule consists of three monovalent antibody Fvs - specific for PD-L1, serum albumin (SA) and 4-1BB - fused in a single chain (a PD-L1/4-1BB/SA tri-specific scDb-scFv). The monovalent and Fc-less structure of the molecule ensures that 4-1BB agonism is conditional upon drug-mediated formation of an immunological synapse between PD-L1+ cells and 4-1BB+ cells, thereby restricting costimulation of 4-1BB+ cells to the tumor microenvironment (TME). Therefore, the scDb-scFv molecule avoids the extratumoral costimulation of immune cells that is believed to cause the dose-limiting toxicities that arise from therapeutic 4-1BB agonism. Meanwhile, the αSA domain extends the molecule’s serum half-life and is expected to promote delivery to the TME. In the present study, we demonstrate that a novel PD-L1/4-1BB/SA tri-specific scDb-scFv potently blocks PD-L1/PD-1 signaling and elicits T cell costimulation solely in the presence of PD-L1+ cells. In in vitro experiments, the scDb-scFv molecule exhibits a greater capacity to costimulate T cells than combinations of clinical stage α4-1BB and αPD-L1/PD-1 IgGs. Moreover, in contrast to ADCC-enabled αPD-L1 IgGs, the Fc-less scDb-scFv spared CD11c+ monocytes from depletion. We also demonstrate that the carefully balanced relative affinity between the molecule’s component αPD-L1 and α4-1BB Fvs maximizes its pharmacological activity and avoids bell-shaped dose-response curves. Next, in vivo efficacy was demonstrated in two xenograft models - HCC827 NCSLC and HCC1954 breast carcinoma - using humanized mice. While equally effective at slowing tumor progression in vivo, the PD-L1/4-1BB/SA tri-specific scDb-scFv was better tolerated, and was more pro-proliferative vis-à-vis intratumoral CD8+ T cells, than combined αPD-L1 and α4-1BB IgGs. In PK/PD studies in cynomologus monkeys, we confirmed the tolerability, pharmacological activity and extended serum half-life of the scDb-scFv molecule. Finally, the molecule was produced from stable CHO cells at high titers (comparable to IgGs) and exhibits outstanding stability characteristics. In conclusion, our data confirm the successful development of a novel therapeutic that is designed to unlock the full potential of combined immunomodulation and overcome its present limitations.

Citation Format: Tea Gunde, Matthias Brock, Stefan Warmuth, Alexandre Simonin, Christian Hess, Eva Oswald, Julia Tietz, Julia Zeberer, Dana Mahler, Simone Muntwiler, Benjamin Küttner, Belinda Wickihalder, Antonia Pölderl, Dania Diem, Teddy Beltrametti, Robin Heiz, Sebastian Meyer, Timothy Egan, David Urech. A novel, monovalent tri-specific antibody-based molecule that simultaneously modulates PD-L1 and 4-1BB exhibits potent anti-tumoral activity in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1532.

Continuous local anaesthetic wound catheter infiltration after clamshell thoracotomy

We report on the novel and successful use of local anaesthetic wound infusions via elastomeric pumps in a 17-year-old male who underwent emergent clamshell thoracotomy after sustaining a stab wound to the flank. This formed one component of a multi-modal analgesic regimen aimed at reducing opioid requirements and their associated side-effects. The patient was mobilising and was discharged from the intensive care unit 24 h postoperatively. There was an unplanned break in the local anaesthetic infusion during which the patient's reported pain scores increased significantly. The catheters were removed on the fifth postoperative day and he was discharged from hospital on day 7.