Genetic Engineering of Transfusable Platelets with mRNA-Lipid Nanoparticles is Compatible with Blood Banking Practices.

Platelets contribute to a variety of physiological processes including inflammation, sepsis and cancer. However, due to their primary role in hemostasis, platelet transfusions are largely restricted to managing thrombocytopenia and bleeding. One way to expand the utility of platelet transfusions would be to genetically engineer donor platelets with new or enhanced functions. We have previously shown that lipid nanoparticles containing mRNA (mRNA-LNP) can be used to genetically modify authentic platelets in a non-clinical crystalloid solution. Currently, platelets collected for transfusion are stored in plasma or in plasma supplemented with platelet additive solution (PAS) at supraphysiological concentrations at room temperature, or at 4 ºC if intended for use in acute hemorrhage. Here we describe a new plasma-optimized mRNA-LNP for transfecting platelets directly in plasma and plasma supplemented with PAS that is scalable to physiological and supraphysiological platelet concentrations. Transfecting platelets in clinical solutions with mRNA-LNP does not affect aspects of in vitro physiology, and transfected platelets are storable. The compatibility of this transfection system with current clinical practices could enable future mRNA-LNP based platelet products and cell therapies.

Safety and immunogenicity of S-Trimer (SCB-2019), a protein subunit vaccine candidate for COVID-19 in healthy adults: a phase 1, randomised, double-blind, placebo-controlled trial.

BACKGROUND: As part of the accelerated development of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), we report a dose-finding and adjuvant justification study of SCB-2019, a protein subunit vaccine candidate containing a stabilised trimeric form of the spike (S)-protein (S-Trimer) combined with two different adjuvants. METHODS: Our study is a phase 1, randomised, double-blind placebo-controlled trial at a specialised clinical trials centre in Australia. We enrolled healthy adult volunteers in two age groups: younger adults (aged 18-54 years) and older adults (aged 55-75 years). Participants were randomly allocated either vaccine or placebo using a list prepared by the study funder. Participants were to receive two doses of SCB-2019 (either 3 µg, 9 µg, or 30 µg) or a placebo (0·9% NaCl) 21 days apart. SCB-2019 either had no adjuvant (S-Trimer protein alone) or was adjuvanted with AS03 or CpG/Alum. The assigned treatment was administered in opaque syringes to maintain masking of assignments. Reactogenicity was assessed for 7 days after each vaccination. Humoral responses were measured as SCB-2019 binding IgG antibodies and ACE2-competitive blocking IgG antibodies by ELISA and as neutralising antibodies by wild-type SARS-CoV-2 microneutralisation assay. Cellular responses to pooled S-protein peptides were measured by flow-cytometric intracellular cytokine staining. This trial is registered with ClinicalTrials.gov, NCT04405908; this is an interim analysis and the study is continuing. FINDINGS: Between June 19 and Sept 23, 2020, 151 volunteers were enrolled; three people withdrew, two for personal reasons and one with an unrelated serious adverse event (pituitary adenoma). 148 participants had at least 4 weeks of follow-up after dose two and were included in this analysis (database lock, Oct 23, 2020). Vaccination was well tolerated, with two grade 3 solicited adverse events (pain in 9 µg AS03-adjuvanted and 9 µg CpG/Alum-adjuvanted groups). Most local adverse events were mild injection-site pain, and local events were more frequent with SCB-2019 formulations containing AS03 adjuvant (44-69%) than with those containing CpG/Alum adjuvant (6-44%) or no adjuvant (3-13%). Systemic adverse events were more frequent in younger adults (38%) than in older adults (17%) after the first dose but increased to similar levels in both age groups after the second dose (30% in older and 34% in younger adults). SCB-2019 with no adjuvant elicited minimal immune responses (three seroconversions by day 50), but SCB-2019 with fixed doses of either AS03 or CpG/Alum adjuvants induced high titres and seroconversion rates of binding and neutralising antibodies in both younger and older adults (anti-SCB-2019 IgG antibody geometric mean titres at day 36 were 1567-4452 with AS03 and 174-2440 with CpG/Alum). Titres in all AS03 dose groups and the CpG/Alum 30 µg group were higher than were those recorded in a panel of convalescent serum samples from patients with COVID-19. Both adjuvanted SCB-2019 formulations elicited T-helper-1-biased CD4+ T-cell responses. INTERPRETATION: The SCB-2019 vaccine, comprising S-Trimer protein formulated with either AS03 or CpG/Alum adjuvants, elicited robust humoral and cellular immune responses against SARS-CoV-2, with high viral neutralising activity. Both adjuvanted vaccine formulations were well tolerated and are suitable for further clinical development. FUNDING: Clover Biopharmaceuticals and the Coalition for Epidemic Preparedness Innovations.

Repair of Tracheoesophageal Fistula via Median Sternotomy Approach.

Tracheoesophageal fistula (TEF) and esophageal atresia (EA) are rare congenital anomalies occurring in approximately 1 in 2500 to 3500 neonates. We present a neonatal patient diagnosed with EA/TEF in conjunction with pulmonary agenesis requiring definitive repair via median sternotomy. The child was born at 33 weeks gestational age with post-delivery respiratory distress necessitating intubation. A nasogastric tube was unable to be passed. After subsequent imaging, TEF and pulmonary agenesis were diagnosed. During planned staged repair with ligation of TEF via standard right thoracotomy approach, significant ventilatory compromise was encountered. Due to concern for ventilatory compromise and anatomical variance limiting visualization, a median sternotomy approach was utilized for definitive repair. This exposure and repair were successful and may be considered for cases with complex pulmonary malformation limiting standard thoracotomy. To our knowledge, this is only the second reported case of a successful TEF/EA repair using a median sternotomy approach.

Pyloric Duplication Cyst in Newborn Male.

An enteric duplication cyst (EDC) is a rare congenital anomaly. Although EDCs can occur at any point throughout the gastrointestinal tract, they are most commonly reported in the ileum and only around 5-7% are of gastroduodenal origin. We report a case of a pyloric duplication cyst in a 3 hour old male with prenatal ultrasound showing a cystic mass. The patient had an abdominal ultrasound after birth that showed a mass with probable trilaminar wall. The diagnosis of pyloric duplication cyst was made in surgery and confirmed with histopathologic examination following resection. The patient is doing well with appropriate weight gain at follow-up appointments.

Surgical Resection of Bilateral Polycystic Ovaries Causing Ureteral Obstruction.

Ovarian cysts in adolescents are typically managed conservatively given the low rate of malignancy and the cysts typically regress over time. We present a case of a 14 year-old female with large bilateral adnexal cysts causing ureteral obstruction which was successfully treated with surgical resection and ensuring maximum preservation of ovarian tissue.

Management of Neuroendocrine Ductal Carcinoma In Situ of the Breast.

Neuroendocrine tumors are defined as tumors that express neuroendocrine markers, specifically synaptophysin and/or chromogranin in at least 50% of tumor cells. To date, neuroendocrine cancers of the breast are extremely rare with reports that they account for less than 1% of all neuroendocrine tumors and less than .1% of all breast cancers. Limited literature exists to guide treatment decisions tailored to neuroendocrine tumors of the breast, despite the possibility that they may be associated with an overall worse prognosis. We present a rare case of neuroendocrine ductal carcinoma in situ (NE-DCIS) which was discovered upon workup for bloody nipple discharge. In this case, NE-DCIS was managed with the standard recommended treatment regimen for ductal carcinoma in situ.

Management of Hidden Cutaneous Melanoma of the Umbilicus.

Melanoma is currently the fifth most common cancer in the United States (US) and most often develop on areas that have increased sun exposure, such as the arms, legs, back or face. The incidence of primary cutaneous melanoma increases each year and curative treatment improves with earlier detection of disease. Primary cutaneous umbilical melanoma is extremely rare with as few as 46 cases reported worldwide. As a result, limited literature is available regarding the management of tumors originating in the umbilicus. By evaluating uncommon areas such as the umbilicus, earlier detection and possible intervention can be provided. We present a rare case of a 33-year-old female with a primary cutaneous melanoma of the umbilicus successfully treated with wide local excision (WLE) and sentinel lymph node biopsy (SLNB).

Surgical Control of Bleeding From Ovarian Torsion in the Setting of Immune Thrombocytopenic Purpura Without Splenectomy.

Immune thrombocytopenic purpura (ITP) is a disorder caused by autoimmune antibodies which target glycoprotein IIb/IIIa complex or other platelet membrane antigens leading to platelet destruction. These platelets are then cleared by the spleen resulting in thrombocytopenia. Immune thrombocytopenic purpura affects about 1 to 6.4 cases in 100 000 children making it one of the most common causes of symptomatic thrombocytopenia in the pediatric population. It is rare that children or adolescents present with serious bleeding due to ITP. Common presentations include petechiae, bleeding gums, or bruising. Bleeding requiring hospitalization or transfusions is unusual and only occurs in approximately 5% of children. Even more uncommon is the presentation of severe bleeding complications requiring surgery for resolution. We present a case of a 17-year-old girl with acute ITP complicated by intraperitoneal hemorrhage and refractory thrombocytopenia due to ovarian cyst requiring oophorectomy.