Rescue from toxic shock

The new vaccine has the potential to treat and prevent the toxic shock caused by streptococcal infection, from which more than 160,000 people die every year.

Streptococcal toxic shock syndrome is an acute condition that often leads to death within a few days. It is caused by streptococci – a group of bacteria that lead to frequent and usually harmless diseases, such as tonsillitis, or unpleasant, but more rare and not fatal – for example, streptodermia.

In about one in a hundred cases, the infection manifests itself as an invasive streptococcal infection, which can quickly lead to death. The mortality rate in this case exceeds 25% even in modern equipped clinics.

In invasive streptococcal infection, strains produce large amounts of toxins that bind to blood proteins, causing activation of T-lymphocytes and a massive inflammatory response of the immune system. As a result, streptococcal toxic shock syndrome (STSS) develops. Invasive streptococcal infection and streptococcal toxic shock are common all over the world, especially among disadvantaged populations, and most often affect very young and very old people.

An international research team, which includes scientists from Melbourne, Australia, and Edmonton, Canada, used transgenic mice with human leukocyte antigens to develop the world's first vaccine against STSS. This vaccine was called J8, it demonstrated a reduction in bacterial load by 1000-1,000,000 times in the spleen and blood.

Using a transgenic mouse model, the authors demonstrated that two proteins are important for the development of toxic shock – streptococcal pyrogenic exotoxin (SpeC) and M-protein. Antibodies in the composition of J8, developed on the basis of these proteins, destroyed infection in mice and eliminated mitogenic and inflammatory activity caused by M-protein.

Vaccination prevented toxic shock, in addition, it led to the production of antibodies in healthy mice. This makes it possible to obtain monoclonal antibodies (antibodies created by identical immune cells that are clones of a unique parent cell) that could be used to study the effectiveness of the J8 vaccine in humans.

Article by M. Pandey et al. Antibodies to the conserved region of the M protein and a streptococcal superantigen cooperatively resolve toxic shock-like syndrome in HLA-humanized mice published in the journal Science Advances.

Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru .