Influence of Gold Nanoparticles on the Immune Response to Rift Valley Fever Vaccine and Related Hepatophysiological Toxicity, Histological, and Immunohistochemical Alterations

INTRODUCTION Vaccination is one of the most important ways to control healthcare costs and stimulate a protective immune response against infection in all countries. Adjuvant carriers can deposit antigens at the injection site, improve their appearance to immunecompetent cells, stimulate T cells, improve antigen processing, and increase B cell antibody secretion . In the preparation of antibodies and vaccines against pathogens, nanoparticles (NPs) are used as carriers and adjuvants. 1,2 NPs interact with the immune system and modulate its activity, resulting in immune stimulation, and have promising medical applications. These modulating effects may be beneficial or harmful. Gold nanoparticles (AuNPs) have the potential to be a useful tool in the development of successful vaccines against infectious diseases. AuNPs penetrate macrophages through receptor-mediated endocytosis and are found primarily in lysosomes and the perinuclear space, depending on their size and shape. The Rift Valley fever virus (RVFV), a member of the genus Phlebovirus in the Bunyaviridae family, causes Rift Valley fever (RVF). In the Arabian Peninsula and Sub-Saharan Africa, RVFV is a mosquito-borne zoonotic pathogen that causes serious outbreaks in humans and livestock. Fever is a symptom of human diseases, which may contribute to retinitis, encephalitis, hemorrhagic fever, and occasionally death. RVFV can be detected using a quantitative reverse transcription polymerase chain reaction (qRT-PCR) or an enzyme-linked immunosorbent assay that detects genomic segments (L, M, S) or surface and nonstructural viral proteins, respectively. These tests have a high sensitivity and specificity, but they necessitate the transport of unknown samples from the field to a laboratory, which increases the risk of virus transmission. Zaher et al. used unmodified gold nanoparticles (AuNPs) that change color in the presence of RVFV RNA to create a prototype point-of-care diagnostic test specific for RVFV detection, resulting in a simple but sensitive assay. The nanogold assay yields qualitative results that Original article