SARS-CoV-2 serology testing: Progress and challenges.

The coronavirus disease 2019 (COVID-19) pandemic has caused the most devasting social and economic impact of this century. The current pandemic will end only after a safe, effective vaccine becomes available and protective herd immunity has been achieved through vaccination. The key parameter to gauge protective immunity is neutralizing antibody levels. Thus, reliable serology testing is essential to diagnose whether an individual has been previously infected, as a large proportion of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections is asymptomatic. For both naturally infected and vaccinated individuals, it is critical to monitor their neutralizing antibody titers over time. This is because, when neutralizing antibody levels wane below a threshold which remains to be determined, they become vulnerable to reinfection. Due to the importance of serology testing, academia and industry have developed different platforms for serological diagnosis, many of which have achieved the Food and Drug Administration (FDA) Emergency Use Authorizations (EUA). Here we summarize the status of COVID-19 serology testing, discuss challenges, and provide future directions for improvement.

Making sense of spike D614G in SARS-CoV-2 transmission.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiologic agent of the current coronavirus disease 2019 (COVID-19) pandemic, has evolved to adapt to human host and transmission over the past 12 months. One prominent adaptive mutation is the asparagine-to-glycine substitution at amino acid position 614 in the viral spike protein (D614G), which has become dominant in the currently circulating virus strains. Since spike protein determines host ranges, tissue tropism, and pathogenesis through binding to the cellular receptor of angiotensin converting enzyme 2 (ACE2), the D614G mutation is hypothesized to enhance viral fitness in human host, leading to increased transmission during the global pandemic. Here we summarize the recent progress on the role of the D614G mutation in viral replication, pathogenesis, transmission, and vaccine and therapeutic antibody development. These findings underscore the importance in closely monitoring viral evolution and defining their functions to ensure countermeasure efficacy against newly emerging variants.

Laryngoscopy Grade Improvement and Difficult Airway Resolution in Infants With Robin Sequence Undergoing Mandibular Distraction Osteogenesis: A Multi-Institutional Study.

OBJECTIVE: Mandibular distraction osteogenesis (MDO) aims to relieve tongue-based airway obstruction in Robin Sequence (RS). We investigated direct laryngoscopy grade (DLG) improvement and difficult airway (DA) resolution following MDO. DESIGN: Retrospective cohort analysis. SETTING: Three tertiary care institutions. PATIENTS: Sixty-four infants with RS who underwent a single MDO procedure in their first year of life were identified from January 2010 to January 2019. MAIN OUTCOME MEASURES: The primary outcome was DLG pre- and post-MDO. Secondary outcomes included DA designation, pre- and post-MDO polysomnographic assessment for obstructive sleep apnea (OSA), length of stay, need for gastrostomy, and major/minor adverse events. RESULTS: Median DLG improved from II pre-MDO to I at the time of distractor removal (n = 43, P < .001). No significant change was seen in patients with a third recorded time point (eg, palatoplasty; n = 78, P = .52). Twenty-six (47%) of 55 patients were designated as DA pre-MDO, and 10 (18%) of 55 patients retained the label post-MDO (P < .01). Five (50%) of these 10 patients appeared to be inappropriately retained. Median obstructive apnea-hypopnea index improved from 38.6 (range 31.2-62.8) pre-MDO to 2.9 (range 1-3.9) post-MDO (n = 12; P = .002). CONCLUSION: Mandibular distraction osteogenesis allowed for DLG improvement that was stably maintained as well as functional improvement in OSA, with minimal morbidity. Difficult airway designation persisted in the electronic record of some infants despite clinical resolution.

Microglial Metabolism After Pediatric Traumatic Brain Injury - Overlooked Bystanders or Active Participants?

Microglia play an integral role in brain development but are also crucial for repair and recovery after traumatic brain injury (TBI). TBI induces an intense innate immune response in the immature, developing brain that is associated with acute and chronic changes in microglial function. These changes contribute to long-lasting consequences on development, neurologic function, and behavior. Although alterations in glucose metabolism are well-described after TBI, the bulk of the data is focused on metabolic alterations in astrocytes and neurons. To date, the interplay between alterations in intracellular metabolic pathways in microglia and the innate immune response in the brain following an injury is not well-studied. In this review, we broadly discuss the microglial responses after TBI. In addition, we highlight reported metabolic alterations in microglia and macrophages, and provide perspective on how changes in glucose, fatty acid, and amino acid metabolism can influence and modulate the microglial phenotype and response to injury.

RNA-Peptide nanoplexes drug DNA damage pathways in high-grade serous ovarian tumors.

DNA damaging chemotherapy is a cornerstone of current front-line treatments for advanced ovarian cancer (OC). Despite the fact that a majority of these patients initially respond to therapy, most will relapse with chemo-resistant disease; therefore, adjuvant treatments that synergize with DNA-damaging chemotherapy could improve treatment outcomes and survival in patients with this deadly disease. Here, we report the development of a nanoscale peptide-nucleic acid complex that facilitates tumor-specific RNA interference therapy to chemosensitize advanced ovarian tumors to frontline platinum/taxane therapy. We found that the nanoplex-mediated silencing of the protein kinase, MK2, profoundly sensitized mouse models of high-grade serous OC to cytotoxic chemotherapy by blocking p38/MK2-dependent cell cycle checkpoint maintenance. Combined RNAi therapy improved overall survival by 37% compared with platinum/taxane chemotherapy alone and decreased metastatic spread to the lungs without observable toxic side effects. These findings suggest (a) that peptide nanoplexes can serve as safe and effective delivery vectors for siRNA and (b) that combined inhibition of MK2 could improve treatment outcomes in patients currently receiving frontline chemotherapy for advanced OC.