One of the biggest challenges in developing efficient vaccines against sexually transmitted diseases (STDs) – such as HIV or the herpes simplex virus – is understanding how to attract specialized immune cells, called CD8 + T cells, to the part of the body by where the virus first enters the body – such as the mucosa of the female genital tract – to establish themselves there.
And it is that, to be fully effective, this type of cells must be waiting in the tissue, ready to provide an immediate protective immune defense, instead of waiting in the bloodstream for an infection to occur, since they pass from the blood the tissues take time and the defensive response is less effective.
Until now, it was believed that the best strategy was to deliver the vaccine directly to the surface of the body where the infection could presumably begin – for example, female genital tissue – so that the immune system could generate CD8 + T cells that would then return to the body. vaccination point there to fight any future viruses they find. The problem is that administering vaccines directly to female genital tissue is not easy or pleasant for the patient, and it is not very efficient either.
A new method
In a study recently published in the journal Nature Communications , researchers from King’s College London have shown that it is possible, through skin vaccination, to generate protective CD8 + T cells that reach the mucous membranes of the genital area.
The team of scientists has discovered that their vaccination strategy brings together a platoon of immune cells – called innate lymphoid cells (ILC1) and monocytes – in genital tissues to work together to release chemicals called chemokines that send out a call to the CD8 + T generated by the vaccine so that they go to the genital tissue. This way, the vaccine does not have to be injected directly there.
“This study shows how specialized groups of innate immune cells in distant tissues can be harnessed to attract protective CD8 + T cells, thus preventing the first tissues where viruses land from becoming infected,” explains the study’s lead author, La Professor Linda Klavinskis, King’s College.
“Now we need to confirm these results with other types of vaccines than the one used in the study to see if the skin vaccine is capable of eliciting a similar response in all cases. If this is shown to be the case, this could have a significant impact on improving the effectiveness of vaccines against sexually transmitted diseases, “adds Klavinskis.
