Amelioration of SARS-CoV-2 infection by ANO6 phospholipid scramblase inhibition.

As an enveloped virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) delivers its viral genome into host cells via fusion of the viral and cell membranes. Here, we show that ANO6/TMEM16F-mediated cell surface exposure of phosphatidylserine is critical for SARS-CoV-2 entry and that ANO6-selective inhibitors are effective against SARS-CoV-2 infections. Application of the SARS-CoV-2 Spike pseudotyped virus (SARS2-PsV) evokes a cytosolic Ca2+ elevation and ANO6-dependent phosphatidylserine externalization in ACE2/TMPRSS2-positive mammalian cells. A high-throughput screening of drug-like chemical libraries identifies three different structural classes of chemicals showing ANO6 inhibitory effects. Among them, A6-001 displays the highest potency and ANO6 selectivity and it inhibits the single-round infection of SARS2-PsV in ACE2/TMPRSS2-positive HEK 293T cells. More importantly, A6-001 strongly inhibits authentic SARS-CoV-2-induced phosphatidylserine scrambling and SARS-CoV-2 viral replications in Vero, Calu-3, and primarily cultured human nasal epithelial cells. These results provide mechanistic insights into the viral entry process and offer a potential target for pharmacological intervention to protect against coronavirus disease 2019 (COVID-19).

Microneedle Array Patch (MAP) Consisting of Crosslinked Hyaluronic Acid Nanoparticles for Processability and Sustained Release.

AIMS: Crosslinked hyaluronic acid (X-linked HA) is not suitable for making microneedles because of the low fluidity of X-linked HA hydrogel. Microneedles were fabricated using X-linked HA nanoparticles (X-linked HA-NPs) to utilize the sustained drug delivery capability of X-linked HA-NPs and to obtain the processability advantages of X-linked HA. METHOD: The puncture performance of a microneedle array patch (MAP) made of crosslinked hyaluronic acid nanoparticles (X-linked HA-NP-MAP) was evaluated by insertion in vitro into porcine skin. After a predetermined attachment time, the remaining height of the X-linked HA-NP-MAP was measured to determine the dissolution rate. X-linked HA-NP-MAP and free HA-MAP containing Rhodamine B isothiocyanate-dextran were administered into the back skin of mice, and the relative fluorescent intensity in the back skin was measured over time. RESULTS: The puncture performance of the X-linked HA-NP-MAP was over 90%. The diameter of redispersed X-linked HA-NPs was same as that of the premolded X-linked HA-NPs. The dissolution rate was not different from that of free HA-MAP. In an in vivo experiment, X-linked HA-NP-MAP was administered into the mouse's back skin successfully and the relative fluorescent intensity of X-linked HA-NP-MAP lasted longer than that of HA-MAP. CONCLUSION: X-linked HA-NPs provide the biocompatibility, the processability of micromolding, sustained drug release, successful penetration into the skin, and relatively short insertion time for full disintegration of NPs in the skin. X-linked HA-NP-MAP can be used for various applications that require several days of sustained drug release.

Delayed-Onset Anaphylaxis Caused by IgE Response to Influenza Vaccination.

Influenza vaccine-associated anaphylaxis is a very rare allergic reaction to vaccines, but the most concerning and life-threatening adverse reaction. Although the safety of influenza vaccines has been well documented, occasional cases of anaphylaxis in vaccinated patients have been reported. In this study, we analyzed the immunoglobulin E (IgE) response to whole influenza vaccines in a pediatric case of delayed-onset anaphylaxis after influenza vaccination. The patient showed elevated specific IgE levels against whole influenza vaccines, especially with split virion from egg-based manufacturing process. Specific IgE levels to influenza vaccines showed decreased over. We evaluated a causal relationship between influenza vaccine and anaphylaxis event by enzyme-linked immunosorbent assay. Delayed-onset anaphylaxis after influenza vaccination can occur in children without predisposing allergic diseases. In addition, the results suggested that formulation and production system of influenza vaccines could affect the probability of severe allergic reaction to vaccines.

Development and clinical study of the use of infrared radiation to accelerate the dissolution rate of a microneedle array patch (MAP).

The dissolution rate of a microneedle array patch (MAP) determines how long a MAP must remain attached to the skin (often called "wear time"). In this study, the dissolution rate of a MAP was increased, not by changing the drug formulation but by employing an infrared (IR) device that is widely used for hospital treatment and in-home therapy. A MAP with microneedles 480 µm in height was prepared using hyaluronic acid (HA). Changes in transepidermal water loss (TEWL), the surface temperature of the skin, and the dissolution rate of the MAP tips with IR irradiation were evaluated on human skin in vivo. Time for recovery from erythema that occurred after MAP attachment and IR irradiation was also evaluated. TEWL increased more than fourfold with IR irradiation. Water that evaporated as a result of IR irradiation was trapped in the skin layer by the patch, resulting in the increased dissolution rate of the MAP tips. After 10 min of IR irradiation, the height of the dissolving tips compared with their initial height increased from 41 to 56%, and the dissolved volume of the tips compared with their initial volume increased from 7 to 18%. During the 10 min of irradiation, the skin surface temperature rose from 32 to 40 °C. Erythema occurred in the early stage of treatment with IR irradiation and MAP attachment, but it abated within 2 h after removal of the MAP and cessation of IR irradiation. Through this study, it was possible to shorten the administration time of MAPs by using an IR device that could be easily accessed. This method can be applied to various types of MAPs in order to reduce the time that the MAPs must remain attached to the skin without changing the drug formulation. Graphical abstract The increase in dissolution rate of dissolving microneedle array patch (MAP) as a result of infrared radiation. a Water-soluble tips of MAP dissolved in water in skin without infrared irradiation. Dotted line indicates the initial dissolving microneedles. b Water in skin and subcutaneous layer evaporated actively with infrared irradiation and was stored under patch of MAP. Increased amount of water in skin induced faster dissolution of MAP tips.