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Cervical cancer ranks as the second most common cancer in women in India, primarily caused by persistent infection with the human papillomavirus (HPV). Given its long latent period, secondary prevention through screening and early detection is essential. However, fear and stigma associated with cancers and the costs involved in disease management are the prominent barriers to its uptake. HPV vaccination is one of the vital components of the World Health Organization's (WHO) Global Strategy to speed up the elimination of cervical cancer as a public health problem. In India, four prophylactic HPV vaccines are currently available. These vaccines are non-infective and highly immunogenic, safe, and effective when administered before HPV exposure. According to WHO recommendations, the primary target group for HPV vaccination consists of girls between the ages of 9 and 14 years. Further, studies have confirmed that both single-dose and two-dose schedules of the HPV vaccine offer comparable efficacy and protection. HPV vaccines are administered intramuscularly in the deltoid region, with 0.5 ml as the standard dose. These vaccines may cause local reactions, as well as mild systemic reactions, such as headache and myalgia, but they are transient. Implementing catch-up vaccination for adolescent girls aged between 9 and 14 years at the time of HPV vaccine introduction would be a cost-effective and sustainable strategy. This would serve as a crucial component of public health efforts to manage HPV infections and eliminate cervical cancer in India. [ABSTRACT FROM AUTHOR]

Getah virus (GETV) is an emerging mosquito-borne virus with economic impact on the livestock industry in East Asia. In this study, we successfully produced GETV virus-like particles (VLPs) in insect cells using the baculovirus expression vector system. We show that the GETV envelope glycoproteins were successfully expressed at the surface of the insect cell and were glycosylated. VLPs were isolated from the culture fluid as enveloped particles of 60–80 nm in diameter. Two 1 µg vaccinations with this GETV VLP vaccine, without adjuvant, generated neutralizing antibody responses and protected wild-type C57/BL6 mice against GETV viremia and arthritic disease. The GETV VLP vaccine may find application as a horse and/or pig vaccine in the future. [ABSTRACT FROM AUTHOR]

Perceived inefficiency and inadequate knowledge of the human respiratory syncytial virus (hRSV) assembly process present a hurdle for large-scale production of authentic hRSV virus-like particles (VLPs) for vaccine purposes. We previously established that the matrix protein, phosphoprotein (P), and fusion protein carboxy-terminus were sufficient to generate VLPs that resemble filamentous wildtype hRSV. Here, the contribution of P was examined. By co-expressing matrix, fusion, and modified P proteins, a ser/thr-rich P region (residues 39–57) was found to be critical for VLP formation, whereas the oligomerization domain was not. Substitutions throughout region 39–57 inhibited VLP formation and relevant amino acids were identified. Phosphomimetic substitutions of serines and threonines inhibited VLP formation; Phosphoblatant substitutions did not. The data show that P not only co-regulates replication and transcription but also has an important role in assembly, mediated by a separate domain that likely interacts with M and/or F and is highly regulated by phosphorylation. • A ser/thr -rich viral assembly domain (AD) was identified in the RSV phosphoprotein. • Several AD residues blocked VLP formation when individually mutated to alanine. • Phosphomimetic substitutions of ser/thr in the AD blocked VLP formation. • The phosphoprotein is multifunctional and highly regulated by phosphorylation. [ABSTRACT FROM AUTHOR]

Vaccines to efficiently block or limit sexual transmission of both HIV and human papilloma virus (HPV) are urgently needed. Chimeric virus-like-particle (VLP) vaccines consisting of both multimerized HPV L1 proteins and fragments of SIV gag p27, HIV-1 tat, and HIV-1 rev proteins (HPV–SHIV VLPs) were constructed and administered to macaques both systemically and mucosally. An additional group of macaques first received a priming vaccination with DNA vaccines expressing the same SIV and HIV-1 antigens prior to chimeric HPV–SHIV VLP boosting vaccinations. Although HPV L1 antibodies were induced in all immunized macaques, weak antibody or T cell responses to the chimeric SHIV antigens were detected only in animals receiving the DNA prime/HPV–SHIV VLP boost vaccine regimen. Significant but partial protection from a virulent mucosal SHIV challenge was also detected only in the prime/boosted macaques and not in animals receiving the HPV–SHIV VLP vaccines alone, with three of five prime/boosted animals retaining some CD4+ T cells following challenge. Thus, although some immunogenicity and partial protection was observed in non-human primates receiving both DNA and chimeric HPV–SHIV VLP vaccines, significant improvements in vaccine design are required before we can confidently proceed with this approach to clinical trials. [Copyright &y& Elsevier]