Adjuvanted Recombinant Glycoprotein E Herpes Zoster Vaccine

Pre-Clinical Development of an Adenovirus Vector Based RSV and Shingles Vaccine Candidate

Respiratory syncytial virus (RSV) infection and shingles are two viral diseases that affect older adults, and a combined vaccine to protect against both could be beneficial. RSV infection causes hospitalisations and significant morbidity in both children and adults and can be fatal in the elderly. The RSV fusion (F) envelope glycoprotein induces a strong RSV-neutralising antibody response and is the target of protective immunity in the first RSV vaccine for older adults, recently approved by the FDA. An initial childhood infection with the varicella zoster virus (VZV) results in chickenpox disease, but reactivation in older adults can cause shingles. This reactivation in sensory and autonomic neurons is characterized by a skin-blistering rash that can be accompanied by prolonged pain. The approved protein-in-adjuvant shingles vaccine induces VZV glycoprotein E (gE)-fspecific antibody and CD4+ T cell responses and is highly effective. Here we report the evaluation of RSV/shingles combination vaccine candidates based on non-replicating chimpanzee adenovirus (ChAd) vectors. We confirmed the cellular and humoral immunogenicity of the vaccine vectors in mice using T cell and antibody assays. We also carried out an RSV challenge study in cotton rats which demonstrated protective efficacy following a homologous prime-boost regimen with our preferred vaccine candidate.

Alphaherpesvirus glycoprotein E: A review of its interactions with other proteins of the virus and its application in vaccinology

The viral envelope glycoprotein E (gE) is required for cell-to-cell transmission, anterograde and retrograde neurotransmission, and immune evasion of alphaherpesviruses. gE can also interact with other proteins of the virus and perform various functions in the virus life cycle. In addition, the gE gene is often the target gene for the construction of gene-deleted attenuated marker vaccines. In recent years, new progress has been made in the research and vaccine application of gE with other proteins of the virus. This article reviews the structure of gE, the relationship between gE and other proteins of the virus, and the application of gE in vaccinology, which provides useful information for further research on gE.

Aging and Options to Halt Declining Immunity to Virus Infections

Immunosenescence is a process associated with aging that leads to dysregulation of cells of innate and adaptive immunity, which may become dysfunctional. Consequently, older adults show increased severity of viral and bacterial infections and impaired responses to vaccinations. A better understanding of the process of immunosenescence will aid the development of novel strategies to boost the immune system in older adults. In this review, we focus on major alterations of the immune system triggered by aging, and address the effect of chronic viral infections, effectiveness of vaccination of older adults and strategies to improve immune function in this vulnerable age group.

Preventing Varicella-Zoster: Advances With the Recombinant Zoster Vaccine

Prevention strategies against varicella zoster infection include chemoprophylaxis with acyclovir and live attenuated zoster vaccine. However, resistance to acyclovir has been problematic, and safety concerns have limited the use of the live attenuated vaccine in immunosuppressed patients. Recombinant zoster vaccine, made available in 2017 for the immunocompetent host, has been evaluated for safety, immunogenicity, and efficacy in several immunocompromised settings as well. The present review compares the live attenuated vaccine and the recombinant zoster vaccine and highlights data on the use of recombinant zoster vaccine in different immunocompromised states. Robust data are available for the safety, immunogenicity, and efficacy of the recombinant vaccine in the autologous stem cell population, particularly among patients with multiple myeloma. The vaccine appears safe and immunogenic in populations including those with cancer (solid tumors and hematologic malignancies), HIV-infected patients, and renal transplant recipients. Efficacy and safety data in other populations are awaited before use of the recombinant vaccine can be more widespread. It is anticipated that an increased use of the recombinant zoster vaccine, particularly in immunosuppressed patients, would lead to a decreased use of acyclovir prophylaxis.