Coronavirus Disease 2019 Vaccine Barriers: Educating Patients to Alleviate Fear of Receiving the Vaccine.

Vaccination is an important step to avoid coronavirus disease 2019 infection and alleviate the disruption caused by the pandemic. Health care providers can improve outcomes by educating themselves and subsequently encouraging patients to vaccinate against the virus. This can be accomplished by understanding how the coronavirus disease 2019 vaccine works and what causes barriers and fear of vaccination.

Biodistribution and Tolerability of AAV-PHP.B-CBh-SMN1 in Wistar Han Rats and Cynomolgus Macaques Reveal Different Toxicologic Profiles.

Recombinant adeno-associated viruses (AAVs) have emerged as promising vectors for human gene therapy, but some variants have induced severe toxicity in Rhesus monkeys and piglets following high-dose intravenous (IV) administration. To characterize biodistribution, transduction, and toxicity among common preclinical species, an AAV9 neurotropic variant expressing the survival motor neuron 1 (SMN1) transgene (AAV-PHP.B-CBh-SMN1) was administered by IV bolus injection to Wistar Han rats and cynomolgus monkeys at doses of 2 × 1013, 5 × 1013, or 1 × 1014 vg/kg. A dose-dependent degeneration/necrosis of neurons without clinical manifestations occurred in dorsal root ganglia (DRGs) and sympathetic thoracic ganglia in rats, while liver injury was not observed in rats. In monkeys, one male at 5 × 1013 vg/kg was found dead on day 4. Clinical pathology data on days 3 and/or 4 at all doses suggested liver dysfunction and coagulation disorders, which led to study termination. Histologic evaluation of the liver in monkeys showed hepatocyte degeneration and necrosis without inflammatory cell infiltrates or intravascular thrombi, suggesting that hepatocyte injury is a direct effect of the vector following hepatocyte transduction. In situ hybridization demonstrated a dose-dependent expression of SMN1 transgene mRNA in the cytoplasm and DNA in the nucleus of periportal to panlobular hepatocytes, while quantitative polymerase chain reaction confirmed the dose-dependent presence of SMN1 transgene mRNA and DNA in monkeys. Monkeys produced a much greater amount of transgene mRNA compared with rats. In DRGs, neuronal degeneration/necrosis and accompanying findings were observed in monkeys as early as 4 days after test article administration. The present results show sensory neuron toxicity following IV delivery of AAV vectors at high doses with an early onset in Macaca fascicularis and after 1 month in rats, and suggest adding the autonomic system in the watch list for preclinical and clinical studies. Our data also suggest that the rat may be useful for evaluating the potential DRG toxicity of AAV vectors, while acute hepatic toxicity associated with coagulation disorders appears to be highly species-dependent.

A Blood-based Test for the Detection of ROS1 and RET Fusion Transcripts from Circulating Ribonucleic Acid Using Digital Polymerase Chain Reaction.

We have developed novel methods for the isolation and characterization of tumor-derived circulating ribonucleic acid (cRNA) for blood-based liquid biopsy. Robust detection of cRNA recovered from blood represents a solution to a critical unmet need in clinical diagnostics. The test begins with the collection of whole blood into blood collection tubes containing preservatives that stabilize cRNA. Cell-free, exosomal, and platelet-associated RNA is isolated from plasma in this test system. The cRNA is reverse transcribed to complementary DNA (cDNA) and amplified using digital polymerase chain reaction (dPCR). Samples are evaluated for both the target biomarker as well as a control gene. Test validation included limit of detection, accuracy, and robustness studies with analytic samples. The method developed as a result of these studies reproducibly detect multiple fusion variants for ROS1 (C-Ros proto-oncogene 1; 8 variants) and RET (rearranged during transfection proto-oncogene; 8 variants). The sample processing workflow has been optimized so that test results can consistently be generated within 72 hours of sample receipt.

Broad vaccine coverage predicted for a bivalent recombinant factor H binding protein based vaccine to prevent serogroup B meningococcal disease.

Factor H binding proteins (fHBP), are bacterial surface proteins currently undergoing human clinical trials as candidate serogroup B Neisseria meningitidis (MnB) vaccines. fHBP protein sequences segregate into two distinct subfamilies, designated A and B. Here, we report the specificity and vaccine potential of mono- or bivalent fHBP-containing vaccines. A bivalent fHBP vaccine composed of a member of each subfamily elicited substantially broader bactericidal activity against MnB strains expressing heterologous fHBP than did either of the monovalent vaccines. Bivalent rabbit immune sera tested in serum bactericidal antibody assays (SBAs) against a diverse panel of MnB clinical isolates killed 87 of the 100 isolates. Bivalent human immune sera killed 36 of 45 MnB isolates tested in SBAs. Factors such as fHBP protein variant, PorA subtype, or MLST were not predictive of whether the MnB strain could be killed by rabbit or human immune sera. Instead, the best predictor for killing in the SBA was the level of in vitro surface expression of fHBP. The bivalent fHBP vaccine candidate induced immune sera that killed MnB isolates representing the major MLST complexes, prevalent PorA subtypes, and fHBP variants that span the breadth of the fHBP phylogenetic tree. Importantly, epidemiologically prevalent fHBP variants from both subfamilies were killed.

Detection of LP2086 on the cell surface of Neisseria meningitidis and its accessibility in the presence of serogroup B capsular polysaccharide.

The outer membrane protein LP2086, a human factor H binding protein, is undergoing clinical trials as a vaccine against invasive serogroup B meningococcal (MnB) disease. As LP2086 is a surface protein, expression of capsular polysaccharide could potentially limit accessibility of anti-LP2086 antibodies to LP2086 expressed on the surface of bacteria. To determine whether variability in expression levels of the serogroup B capsule (Cap B) might interfere with accessibility of anti-LP2086 antibody binding to LP2086, we evaluated the ability of anti-Cap B and anti-LP2086 antibodies to bind to the surface of 1263 invasive clinical MnB strains by flow cytometry. One of the anti-LP2086 monoclonal antibodies used recognizes virtually all LP2086 sequence variants. Our results show no correlation between the amount of Cap B expressed and the binding of anti-LP2086 antibodies. Furthermore, the susceptibility of MnB bacteria to lysis by anti-LP2086 immune sera was independent of the level of Cap B expressed. The data presented in this paper demonstrates that Cap B does not interfere with the binding of antibodies to LP2086 expressed on the outer membrane of MnB clinical isolates.

Outer membrane protein (OMP) based vaccine for Neisseria meningitidis serogroup B.

A family of outer membrane lipoproteins of Neisseria meningitidis, LP2086, has been shown to induce serum bactericidal activity against a broad variety of meningococcal strains. Two sub-families of serologically distinct LP2086 proteins (A and B) have been identified. In the present study, we have shown that polyclonal anti-serum against rLP2086 is protective in vivo in an infant rat passive-protection model. Additionally, the LP2086 protein is displayed on the surface of 91% meningococcal strains as measured in a whole cell ELISA using polyclonal anti-sera raised against these proteins. We also demonstrate based on the reactivity of anti-rLP2086 antibody with recombinantly expressed C- and N-terminal fragments of rLP2086 in a Western blot assay that the C-terminal fragment of LP2086 dictates sub-family specificity and the N-terminal fragment determines the family specificity. A formulation containing family A and B of LP2086 potentially would provide broad protection against a majority of Neisseria meningitidis strains.