Live Attenuated Zoster Vaccine Boosts Varicella Zoster Virus (VZV)-Specific Humoral Responses Systemically and at the Cervicovaginal Mucosa of Kenyan VZV-Seropositive Women

Oral Polio Vaccine to Protect Against COVID-19: Out of the Box Strategies?

The global coronavirus disease 2019 pandemic has raised significant concerns of developing rapid, broad strategies to protect the vulnerable population and prevent morbidity and mortality. However, even with an aggressive approach, controlling the pandemic has been challenging, with concerns of emerging variants that likely escape vaccines, nonadherence of social distancing/preventive measures by the public, and challenges in rapid implementation of a global vaccination program that involves mass production, distribution, and execution. In this review, we revisit the utilization of attenuated vaccinations, such as the oral polio vaccine, which are safe, easy to administer, and likely provide cross-protection against respiratory pathogens. We discuss the rationale and data supporting its use and detail description of available vaccines that could be repurposed for curtailing the pandemic.

Effect of water immersion restraint stress on gastric mucosa in rats with removed salivary glands

OBJECTIVE

To explore the effect of salivary gland removal on water immersion restraint stress (WIRS)-induced gastric mucosal injury (GMI) in rats.

METHODS

Eighty male WISTAR rats were allocated into sham operation (sham) group, sham + WIRS group, salivary gland removal group, and salivary gland removal + WIRS group, with 20 rats in each group. In the sham group, skin and subcutaneous tissues were cut to expose glands. The rats in other three groups were subjected to a total salivary gland resection, and all their submandibular glands and sublingual glands and part of the parotid glands were removed, and the parotid duct was ligated. Afterwards, rats were exposed to WIRS for one and a half months and sacrificed. The severity of GMI was scored, and any histologic and ultrastructural changes were monitored.

RESULTS

There were differences in the Guth index (GMI evaluation) scores among the four groups (P=0.000), which were higher in salivary gland removal + WIRS group than those in the other three groups (all P<0.001), and were higher in the sham + WIRS group and salivary gland removal group than those in the sham group (all P=0.000). Compared with other groups, the gastric mucosa was severely injured in the salivary gland removal + WIRS group, with obvious congestion, edema, inflammatory cell infiltrate, mucosal shedding, bleeding ulcers, enlarged intercellular spaces, and damaged organelles.

CONCLUSION

Salivary gland removal aggravates WIRS-induced GMI to a certain extent.

Live attenuated varicella-zoster virus vaccine does not induce HIV target cell activation

BACKGROUND

Varicella-zoster virus (VZV) is under consideration as a promising recombinant viral vector to deliver foreign antigens including HIV. However, new vectors have come under increased scrutiny, since trials with adenovirus serotype 5-vectored (Ad5-vectored) HIV vaccine demonstrated increased HIV risk in individuals with pre-immunity to the vector that was thought to be associated with mucosal immune activation (IA). Therefore, given the prospect of developing an HIV/VZV chimeric vaccine, it is particularly important to define the impact of VZV vaccination on IA.

METHODS

Healthy VZV-seropositive Kenyan women (n = 44) were immunized with high-dose live attenuated VZV vaccine, and we assessed the expression on CD4+ T cells isolated from blood, cervix, and rectum of IA markers including CD38 and HLA-DR and of markers of cell migration and tissue retention, as well as the concentration of genital and intestinal cytokines. A delayed-start group (n = 22) was used to control for natural variations in these parameters.

RESULTS

Although immunogenic, VZV vaccination did not result in significant difference in the frequency of cervical activated (HLA-DR+CD38+) CD4+ T cells (median 1.61%, IQR 0.93%-2.76%) at 12 weeks after vaccination when compared with baseline (median 1.58%, IQR 0.75%-3.04%), the primary outcome for this study. VZV vaccination also had no measurable effect on any of the IA parameters at 4, 8, and 12 weeks after vaccination.

CONCLUSION

This study provides the first evidence to our knowledge about the effects of VZV vaccination on human mucosal IA status and supports further evaluation of VZV as a potential vector for an HIV vaccine.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02514018.

FUNDING

Primary support from the Canadian Institutes for Health Research (CIHR). For other sources, see Acknowledgments.