Human rhinovirus polyprotein (HRV polyprotein)

Human rhinovirus (HRV) antigens encompass the structural and non-structural proteins derived from the viral polyprotein, which are critical for the virus's ability to infect host cells and replicate (Native Antigen Company, 2020) [14]. The structural proteins VP1, VP2, VP3, and VP4 assemble into an icosahedral capsid that protects the viral RNA and facilitates cell entry; VP1 is particularly notable for containing a hydrophobic pocket that serves as a target for capsid-stabilizing drugs like pleconaril (PMC, 2008) [8]. Non-structural proteins, most importantly the 3C and 2A proteases, are responsible for the proteolytic processing of the polyprotein into individual functional components, making them vital targets for antiviral inhibition by compounds such as rupintrivir (Taylor & Francis, 2019) [6]. HRV is the primary cause of the common cold and a major driver of complications in patients with underlying respiratory conditions, such as asthma and chronic obstructive pulmonary disease (COPD) (PMC, 2017) [9]. Therapeutic development against these antigens is complicated by the existence of more than 160 distinct serotypes and the virus's propensity for developing resistance mutations in drug-binding regions (MDPI, 2022) [12]. Consequently, while several small molecules have reached clinical trials, none have yet achieved widespread regulatory approval for the general population (Frontiers, 2018) [18].

Other names

Rhinovirus antigensHuman rhinovirus antigensHRV antigensRhinovirus capsid proteinsRhinovirus 3C proteaseRhinovirus 2A proteaseVP1VP2VP3VP4

Drugs targeting rhinovirus antigens primarily act through two mechanisms: capsid stabilization and protease inhibition (PMC, 2019) [2]. Capsid binders like pleconaril and pirodavir bind to a hydrophobic pocket in the VP1 protein, preventing the conformational changes required for viral uncoating and RNA release into the host cell (PMC, 2008) [8]. Protease inhibitors like rupintrivir target the viral 3C protease, an enzyme essential for cleaving the viral polyprotein into functional structural and non-structural proteins, thereby halting viral replication (PNAS, 1999) [3].