Functional binding of PD1 ligands predicts response to anti-PD1 treatment in patients with cancer

Accurate predictive biomarkers of response to immune checkpoint inhibitors (ICIs) are required for better stratifying patients with cancer to ICI treatments. Here, we present a new concept for a bioassay to predict the response to anti-PD1 therapies, which is based on measuring the binding functionality of PDL1 and PDL2 to their receptor, PD1. In detail, we developed a cell-based reporting system, called the immuno-checkpoint artificial reporter with overexpression of PD1 (IcAR-PD1) and evaluated the functionality of PDL1 and PDL2 binding in tumor cell lines, patient-derived xenografts, and fixed-tissue tumor samples obtained from patients with cancer. In a retrospective clinical study, we found that the functionality of PDL1 and PDL2 predicts response to anti-PD1 and that the functionality of PDL1 binding is a more effective predictor than PDL1 protein expression alone. Our findings suggest that assessing the functionality of ligand binding is superior to staining of protein expression for predicting response to ICIs.

The evolution of walking-related outcomes over the first 12 weeks of rehabilitation for incomplete traumatic spinal cord injury: the multicenter randomized Spinal Cord Injury Locomotor Trial

BACKGROUND

The Spinal Cord Injury Locomotor Trial (SCILT) compared 12 weeks of step training with body weight support on a treadmill (BWSTT) that included overground practice to a defined but more conventional overground mobility intervention (CONT) in patients with incomplete traumatic SCI within 8 weeks of onset. No previous studies have reported walking-related outcomes during rehabilitation.

METHODS

This single-blinded, randomized trial entered 107 American Spinal Injury Association (ASIA) C and D patients and 38 ASIA B patients with lesions between C5 and L3 who were unable to walk on admission for rehabilitation. The Functional Independence Measure (FIM-L) for walking, 15-m walking speed, and lower extremity motor score (LEMS) were collected every 2 weeks.

RESULTS

No significant differences were found at entry and during the treatment phase (12-week mean FIM-L = 5, velocity = 0.8 m/s, LEMS = 35, distance walked in 6 min = 250 m). Combining the 2 arms, a FIM-L >or= 4 was achieved in < 10% of ASIA B patients, 92% of ASIA C patients, and all of ASIA D patients. Walking speed of >or= 0.6 m/s correlated with a LEMS near 40 or higher.

CONCLUSIONS

Few ASIA B and most ASIA C and D patients achieved functional walking ability by the end of 12 weeks of BWSTT and CONT, consistent with the primary outcome data at 6 months. Walking-related measures assessed at 2-week intervals reveal that time after SCI is an important variable for entering patients into a trial with mobility outcomes. By about 6 weeks after entry, most patients who will recover have improved their FIM-L to >3 and are improving in walking speed. Future trials may reduce the number needed to treat by entering patients with FIM-L < 4 at > 8 weeks after onset if still graded ASIA B and at > 12 weeks if still ASIA C.

Weight-supported treadmill vs over-ground training for walking after acute incomplete SCI

OBJECTIVE

To compare the efficacy of step training with body weight support on a treadmill (BWSTT) with over-ground practice to the efficacy of a defined over-ground mobility therapy (CONT) in patients with incomplete spinal cord injury (SCI) admitted for inpatient rehabilitation.

METHODS

A total of 146 subjects from six regional centers within 8 weeks of SCI were entered in a single-blinded, multicenter, randomized clinical trial (MRCT). Subjects were graded on the American Spinal Injury Association Impairment Scale (ASIA) as B, C, or D with levels from C5 to L3 and had a Functional Independence Measure for locomotion (FIM-L) score < 4. They received 12 weeks of equal time of BWSTT or CONT. Primary outcomes were FIM-L for ASIA B and C subjects and walking speed for ASIA C and D subjects 6 months after SCI.

RESULTS

No significant differences were found at entry between treatment groups or at 6 months for FIM-L (n = 108) or walking speed and distance (n = 72). In the upper motor neuron (UMN) subjects, 35% of ASIA B, 92% of ASIA C, and all ASIA D subjects walked independently. Velocities for UMN ASIA C and D subjects were not significantly different for BWSTT (1.1 +/- 0.6 m/s, n = 30) and CONT (1.1 +/- 0.7, n = 25) groups.

CONCLUSIONS

The physical therapy strategies of body weight support on a treadmill and defined overground mobility therapy did not produce different outcomes. This finding was partly due to the unexpectedly high percentage of American Spinal Injury Association C subjects who achieved functional walking speeds, irrespective of treatment. The results provide new insight into disability after incomplete spinal cord injury and affirm the importance of the multicenter, randomized clinical trial to test rehabilitation strategies.

[Nonbiodegradable drug-sustained capsular ring for prevention of secondary cataract. Part II: In vivo evaluation]

PURPOSE

The appearance of a secondary cataract constitutes the most common complication of cataract surgery since the advent of phacoemulsification. Prevention is today one of the crucial challenges of research in ophthalmology. We have developed a drug-sustained capsular ring releasing 5-fluorouracil (5-FU). This system targets the goal of combining advantageous mechanical and pharmacological properties with the ability to interfere on the epithelial cellular processes of secondary cataract. This paper presents the results of animal evaluation.

MATERIAL AND METHODS

The study first developed the in vitro delivery system as a preliminary step to the animal in vivo approach. After a pilot study conducted on micro pigs, lens extraction was performed on the right eye of 22 female albino rabbits. The four study groups included: group 1 (6 animals) as a control group receiving only phacoemulsification; group 2 (6 animals) receiving phacoemulsification and the implantation of a nonsustained capsular tension ring; and group 3 (6 animals) receiving a drug-sustained ring. Group 4 (4 animals), implanted with a 5-FU-sustained ring, was reserved for staged samples of aqueous humor for kinetic determination of active agent release.

RESULTS

Clinical evaluation based on biomicroscopy and histology showed a lesser reaction of secondary cataract in eyes with the ring. Compared to group 1, central posterior capsular opacification appeared significantly lower in density and surface in groups 2 and 3. No intraocular toxicity was observed. The poor sensitivity of the 5-FU detection method (high-performance chromatography) impaired pharmacokinetic evaluation.

DISCUSSION

CONCLUSIONS

The decrease in secondary cataract reaction in cases of implanted capsular ring demonstrated the advantages of its mechanical effect. However, the benefit of an additive pharmacological action related to the release of 5-FU could not be proved. Nevertheless, the theoretical concept of a drug-sustained delivery system seems attractive and thus calls for evaluation of other potential modulators of cell behavior.

[Non-biodegradable drug-sustained capsular ring for prevention of secondary cataract. Part I: In vitro evaluation]

PURPOSE

The appearance of secondary cataract constitutes the most common complication of cataract surgery since the advent of phacoemulsification. Prevention is today one of the most crucial challenges of research in ophthalmology. We have developed a drug-sustained capsular ring releasing 5-fluorouracil (5-FU). This system aims to combine mechanical and pharmacological properties with the ability to interfere on the lens epithelial cellular processes of secondary cataract. This first article will report on the in vitro evaluation of this system.

MATERIALS AND METHOD

Development of a hydrogel that can serve as a mechanical support and as a release of an active agent requires a comparative trial of multiple hydrophobic products providing rigidity to the ring and of hydrophilic products providing the ability to release a drug. The choice of 5-FU as a non-proliferate agent was based on its well-known pharmacological properties and its wide use in ophthalmology. Evaluation comprised adjustment of the adequate copolymer, then of the loading phase, and finally assessment of 5-FU release. The mechanical characteristics and cytocompatibility of the ring were also assessed.

RESULTS

The characteristics of drug release differed depending on the water content and resulting volume of the copolymer. The pharmaceutical and mechanical testing led to selecting the HPMA-MMA combination (75:25). However, a burst effect within the first 2 hours was observed in all cases. That limit was eliminated by creating a biodegradable surface coating of Poly Lactid-co-Glycolid (PLG 50:50) that could provide a positive barrier effect against migration and a controlled continual release of 0.25 microg/h extended to 9 days. Mechanical tests of tension, compression, and traction showed the crucial influence of the ring's hydration state. The cytocompatibility study showed no evidence of cellular toxicity.

DISCUSSION/CONCLUSIONS

The synthesized copolymer is able to release a constant, regular and safe rate of 5-FU, higher than CI50 over a period of 9 days for a cell proliferation phase of 3-5 days. We adjusted the ring associating the mechanical properties and the ability to release 5-FU, allowing further evaluation on animal models, the subject of the second part of this report.

Evidence of hyaluronic acid and hyaluronic acid binding sites on human corneal endothelium

A highly specific hyaluronic acid (HA) recognizing protein (HABR) was used to study whether the human corneal endothelium is covered by HA and to quantify the amount. Tritiated high molecular weight HA was used to determine the capacity of the human endothelium to bind exogenous HA. Human corneas were obtained from keratoconus patients having corneal transplantation and from postmortem eyes. The corneas were immersed in a 4% formaldehyde solution containing 1% cetylpyridine chloride for histochemistry, frozen for biochemistry, or used for 3H-HA (Mr 3 x 10(6) binding. For the biochemical determinations, 125I-labeled HABR was used. Tritiated HA was used for the binding experiment. A specific layer of HA covering the endothelial cells of the corneal buttons was demonstrated. The biochemical analysis also revealed the presence of HA. Finally, the human endothelial cells had specific hyaluronic acid binding sites.

Phrenic nerve pacing of the quadriplegic patient

Phrenic nerve pacing can be used to free a quadriplegic patient from ventilatory dependency. During a 6-year period (1982 to 1988), 23 patients with an age range of 17 to 63 years (mean 31 years) underwent implantation of a phrenic nerve pacemaker because of ventilatory dependency resulting from quadriplegia. Fourteen patients had a unilateral phrenic nerve implant and nine had a bilateral implant. The time from injury to implantation was 12 to 16 weeks. The site of implantation was the cervical phrenic nerve in 13 patients and the thoracic phrenic nerve in 10 patients. During the past 24 months, only a transthoracic approach has been used. The indication for pacing was failure to be weaned from ventilatory support in all patients. Failure to stimulate the phrenic nerve at implantation was noted in three patients, despite preoperative testing indicating an acceptable response. There were no deaths, and minor complications developed in three patients. Follow-up is available in all patients: Eight patients are completely free from the ventilator; nine patients are in markedly improved condition but require the ventilator at night; three patients are in moderately improved condition; and three patients had no response. Three patients required reexploration for component failure from 6 weeks to 18 months after implantation.

[Congenital corneal opacity caused by thickening of Bowman's membrane]

Congenital corneal opacifications are rare, yet their causes are manifold. Only a few cases have been described in which the most striking histopathological feature is a thickening of Bowman's membrane. The authors found an isolated thickening of this membrane in the corneas of a baby who, shortly after birth, presented with corneal opacifications in both eyes. Only a few months after penetrating keratoplasty was performed the condition recurred. Bowman's membrane was found to be thickened in the graft as well.

Cushing's syndrome due to ectopic ACTH production by a nasal paraganglioma

A patient is described with Cushingoid features and a tumor of the paranasal sinuses. Laboratory studies revealed hyperglycemia, hypokalemia, alkalosis, hypercortisolemia, and elevated serum ACTH levels. The cortisol level increased briskly in response to parenteral ACTH, but was only partially suppressed by dexamethasone. Microscopically, the tumor was found to be a paraganglioma containing many neurosecretory granules.. Treatment with methyrapone, o,p'DDD, and irradiation of the tumor resulted in a lasting remission. It is concluded that this unique patient suffered from Cushing's syndrome due to ectopic ACTH production by a paraganglioma of the paranasal sinuses.

The syndrome of inappropriate antidiuretic hormone secretion in multiple sclerosis

The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) occurred during an excerbation of multiple sclerosis (MS). Rapid symptomatic improvement occurred with correction of the hyponatremia. Although the pathophysiology responsible for development of the SIADH in this patient is unknown, CNS involvement by MS is a likely explanation.

Acute choroidal ischemia as a complication of photocoagulation

Acute choroidal vascular insufficiency as a complication of photocoagulation has been little noticed. In 17 eyes of 16 patients photocoagulated with either xenon or argon sources for proliferative sickle cell retinopathy, gray lesions of the fundus developed peripheral to the photocoagulation sites. Histologic examination of similar gray lesions produced in monkeys showed necrosis and atrophy of the outer half of the retina. Intense photocoagulation of the human fundus, even with smaller spot sizes, may occlude a choroidal artery, producing separate gray lesions of distinctive shape. The lesions in both the patients and the monkeys progressed to granular hyperpigmentation by two to three weeks after photocoagulation.

Angioid streaks and sickle haemoglobinopathies

Five patients had angioid streaks associated with sickle cell haemoglobinopathy. Other diseases associated with angioid streaks were ruled out, as was elastic tissue degenegation in sickle cell patients. After studying over 350 patients, we believe the incidence of angioid streaks in sickle cell disease to be between 1 and 2 per cent.