The molecular mechanism of enterovirus infection uncovering; the study finding that body proteins called albumin and certain ions within the attacked host cells can affect the genetic workings of enteroviruses; and enhance their infection. The researchers explain that enteroviruses are one of the commonest infections leading to both acute as well as chronic infections.
These are successful viruses that can cause several infectious illnesses. Most of these infections are mild but if the virus affects the central nervous system, the infection can get severe. Polio viruses for example are enteroviruses and so are viruses that lead to hand, foot and mouth disease (HFMD). In 9 out of 10 infected persons there may be mild or no symptoms of the infection. In the others there may be fever, flu like illness, muscle and body aches and a rash along with gastrointestinal symptoms such as abdominal pain, cramps and diarrhoea.
Mechanism of enterovirus infection
According to the European Centre for Disease Prevention and Control, the way the infection spreads is via secretions from infected persons including saliva, mucus or sputum or feces. Children are most vulnerable to this infection and persons with a risk of complications with this infection include those who are young, old, pregnant or with low immunity.
However, the study finding that the molecular mechanisms of why enterovirus infections are more severe in some and generally mild in most individuals were not well understood. For this the team used real time measurements of the uncoating of the virus in high resolutions. They noted that there was a common molecule within the serum as well as the interstitial fluids; made up of albumin and ions from the vescicles of the cells that could help the multiplication of the virus particle.
The virus particle
But the researchers noted that the virus becomes more expanded and fenestrated. This allows the smaller molecules such as ions to enter into it. Before the ions can enter, the virus particle is first primed by the albumin present in the host cell; the team explains. The albumin primed virus particle becomes “metastable” or “infectious intermediate”, the write. As the ions enter into the virus particle; they alter the genome to cause release of the genome; and this facilitates the multiplication of the virus within the body.
The team used radioactively labelled enterovirus particle; and performig real-time spectroscopy using sucrose gradients. They explained that at 37 degrees the albumin in the host cell triggered metastable uncoating; intermediate of echovirus 1 without receptor engagement. They also added that this process of activation of the virus; by the albumin could be blocked by saturating the albumin present in the host cells using fatty acids.