Humanized anti-DEspR IgG4S228P antibody increases overall survival in a pancreatic cancer stem cell-xenograft peritoneal carcinomatosis ratnu/nu model.

BACKGROUND: Pancreatic peritoneal carcinomatosis (PPC), with the worst median overall-survival (mOS), epitomizes the incurability of metastatic cancer. Cancer stem cells (CSCs) underpin this incurability. However, inhibitors of CSC-stemness fail to increase mOS in cancer patients despite preclinical tumor-reduction. This shortfall reinforces that preclinical efficacy should be defined by increased mOS in the presence of cancer comorbidities, CSC-heterogeneity and plasticity. The primary objectives of this study are: to test the dual endothelin-1/signal peptide receptor, DEspR, as a nodal therapeutic target in PPC, given DEspR induction in anoikis-resistant pancreatic CSCs, and to validate humanized anti-DEspR antibody, hu-6g8, as a potential therapeutic for PPC. METHODS: We used heterogeneous pools of CSCs selected for anoikis resistance from reprogrammed Panc1 and MiaPaCa2 tumor cells (TCs), and adherent TCs reprogrammed from CSCs (cscTCs). We used multiple anti-DEspR blocking antibodies (mAbs) with different epitopes, and a humanized anti-DEspR recombinant mAb cross-reactive in rodents and humans, to test DEspR inhibition effects. We measured DEspR-inhibition efficacy on multiple prometastatic CSC-functions in vitro, and on tumorigenesis and overall survival in a CSC-derived xenograft (CDX) nude rat model of PPC with comorbidities. RESULTS: Here we show that DEspR, a stress-survival receptor, is present on subsets of PDAC Panc1-TCs, TC-derived CSCs, and CSC-differentiated TCs (cscTCs), and that DESpR-inhibition decreases apoptosis-resistance and pro-metastatic mesenchymal functions of CSCs and cscTCs in vitro. We resolve the DNA-sequence/protein-function discordance by confirming ADAR1-RNA editing-dependent DEspR-protein expression in Panc1 and MiaPaCa2 TCs. To advance DEspR-inhibition as a nodal therapeutic approach for PPC, we developed and show improved functionality of a recombinant, humanized anti-DEspR IgG4S228P antibody, hu-6g8, over murine precursor anti-DEspR mabs. Hu-6g8 internalizes and translocates to the nucleus colocalized with cyto-nuclear shuttling galectins-1/3, and induces apoptotic cell changes. DEspR-inhibition blocks transperitoneal dissemination and progression to peritoneal carcinomatosis of heterogeneous DEspR±/CD133 ± Panc1-derived CSCs in xenografted nude rats, improving mOS without chemotherapy-like adverse effects. Lastly, we show DEspR expression in Stage II-IV primary and invasive TCs in the stroma in PDAC-patient tumor arrays. CONCLUSION: Collectively, the data support humanized anti-DEspR hu-6g8 as a potential targeted antibody-therapeutic with promising efficacy, safety and prevalence profiles for PPC patients.

Clinical safety and efficacy of a preloaded monofocal hydrophobic acrylic intraocular lens in a real-world population.

BACKGROUND: This study was designed to evaluate visual, refractive and safety outcomes in eyes after they underwent phacoemulsification and implantation of a preloaded monofocal hydrophobic acrylic intraocular lens. METHODS: This was a single center observational study conducted at Ashford and St Peter's Hospitals NHS Foundation Trust, United Kingdom. Patients were included if they had cataract extraction with in-the-bag implantation of the EyeCee® One preloaded intraocular lens from August to October 2019. Pre-operative, surgery-related and 2 weeks and 3 months post-operative data was collected. Surgeons at this trust were then asked to complete a feedback form to evaluate their experience of implanting the EyeCee® One. RESULTS: One hundred fifty-two eyes were included in the study. Ninety-four (62%) of these eyes had cataract but no concomitant ocular pathology that could potentially affect visual acuity. Three months post-operatively, 98.7% of all eyes had monocular CDVA ≤0.3 logMAR. 100% of the eyes without concomitant ocular pathology achieved this target. The mean CDVA of all eyes in this study improved from 0.43 ± 0.43 logMAR pre-operatively, to 0.05 ± 0.11 logMAR post-operatively (p < 0.05). The mean sphere and spherical equivalent values showed significant improvements (p < 0.05) and (p < 0.05). There were no intraoperative complications and 1.3% of patients reported complications 2 weeks post-operatively. All of the participating surgeons said they would use the EyeCee® One again with 64% providing an overall rating of 'excellent' for their experience of implanting this intraocular lens. CONCLUSIONS: This study indicates excellent post-operative visual acuity and refractive outcomes in eyes after EyeCee® One implantation. This is accompanied with very little risk of intraoperative and post-operative complications.

Restarting cataract surgery during the COVID-19 pandemic; a prospective study analysing 30 day outcomes after elective cataract surgery in the United Kingdom.

BACKGROUND: Cataract is a significant cause of preventable blindness in the United Kingdom and worldwide. Prior to the COVID-19 pandemic, cataract surgery was the most commonly performed operation by the National Health Service in the United Kingdom. The aim of this study is to evaluate the safety of elective cataract surgery performed in the United Kingdom in a COVID-19 free hospital during the COVID-19 pandemic. METHODS: Single centre prospective observational cohort study of consecutive patients undergoing elective cataract surgery in the United Kingdom over a 3 month period from May to August 2020. Electronic medical records were reviewed and patients were contacted at 30 days post-operatively. Data collection included symptoms suggestive of COVID-19 infection, hospital admission, mortality, intra-operative and post-operative surgical complications. RESULTS: A total of 649 elective cataract surgeries were performed. Two patients (0.3%) developed worsening dyspnoea during the 30 day post-operative period, but tested negative for COVID-19 infection. Three patients (0.5%) were hospitalised, unrelated to COVID-19 infection, of which one patient (0.2%) passed. Four patients (0.6%) suffered posterior capsular rupture. 601 (93.2%) had no post-operative complications. CONCLUSION: This study demonstrates a safe model for the resumption of elective cataract surgery during the COVID-19 pandemic, providing strict infection control measures are in place.

Refractive surprise after cataract surgery secondary to smeared optics of swept-source optical coherence tomography biometer: a case report.

BACKGROUND: Inaccurate biometry can lead to the wrong intraocular lens implantation and result in refractive surprise following cataract surgery. It is important to be sceptical of biometry results that do not match the refractive or clinical picture and ask for it to be repeated. CASE PRESENTATION: We present a unique cause of refractive surprise in a patient undergoing cataract surgery. Pre-operative refraction demonstrated hypermetropia, yet swept-source optical coherence tomography (SS-OCT) biometry repeatedly calculated the axial length as > 35.00 mm in both eyes. The patient underwent phacoemulsification and intraocular lens insertion using the provided biometry calculations, however post-operatively the patient had a + 14.00 dioptre refractive surprise. Analysis of biometry performed on the same day identified other patients with exaggerated axial lengths, supporting the theory that the biometer's smeared optical surface was responsible. Following servicing of the machine, repeat biometry of the patient calculated the axial length consistent with a hypermetrope (21.67 mm) and the intraocular lens exchange was successful in correcting the refractive error. CONCLUSIONS: Ensure the optical surfaces of the biometer are cleaned regularly, and consider repeating biometry on separate days if repeat biometry still is not in keeping with the refractive or clinical picture. Additionally, re-confirm the axial length with another modality.

A Case of Acute Myeloid Leukaemia Presenting as Subacute Intracranial Hypertension in a Young Adult.

We report a case of an 18-year-old woman presenting with headache, papilloedema, and cerebrospinal fluid (CSF) pleocytosis. She was subsequently diagnosed with acute myeloid leukaemia, which is to date the only reported case manifesting as central nervous system-localised disease in an adult. The intracranial hypertension was treated successfully with chemotherapy, acetazolamide, and CSF drainage, with no permanent visual impairment. The mechanism by which haematological malignancy causes intracranial hypertension is not fully elucidated, but we hypothesise that in our case, blast infiltration interfered with CSF reabsorption at the arachnoid granulations.

A deimmunised form of the ribotoxin, α-sarcin, lacking CD4+ T cell epitopes and its use as an immunotoxin warhead.

Fungal ribotoxins that block protein synthesis can be useful warheads in the context of a targeted immunotoxin. α-Sarcin is a small (17 kDa) fungal ribonuclease produced by Aspergillus giganteus that functions by catalytically cleaving a single phosphodiester bond in the sarcin-ricin loop of the large ribosomal subunit, thus making the ribosome unrecognisable to elongation factors and leading to inhibition of protein synthesis. Peptide mapping using an ex vivo human T cell assay determined that α-sarcin contained two T cell epitopes; one in the N-terminal 20 amino acids and the other in the C-terminal 20 amino acids. Various mutations were tested individually within each epitope and then in combination to isolate deimmunised α-sarcin variants that had the desired properties of silencing T cell epitopes and retention of the ability to inhibit protein synthesis (equivalent to wild-type, WT α-sarcin). A deimmunised variant (D9T/Q142T) demonstrated a complete lack of T cell activation in in vitro whole protein human T cell assays using peripheral blood mononuclear cells from donors with diverse HLA allotypes. Generation of an immunotoxin by fusion of the D9T/Q142T variant to a single-chain Fv targeting Her2 demonstrated potent cell killing equivalent to a fusion protein comprising the WT α-sarcin. These results represent the first fungal ribotoxin to be deimmunised with the potential to construct a new generation of deimmunised immunotoxin therapeutics.

Pre-clinical considerations in the assessment of immunogenicity for protein therapeutics.

Protein therapeutics offer distinct advantages over other classes of drugs largely due to the high level of target specificity and generally low toxicity. Problems have, however, been encountered with some protein therapeutics inducing undesirable immune responses in patients. This immunogenicity can produce pleiotropic effects including the development of a high affinity B cell-mediated humoral response that is often directed against the therapeutic. Opinions are divided as to the principal causes of clinical immunogenicity and, as a result, this area has been the subject of much research. One thing that has emerged as a result of this intense activity is the development of pre-clinical models that can provide a level of prediction of the immunogenic potential of novel protein therapeutics before administration in man.