Research

Removal of inhibitory immune cells temporarily increases efficiency, 
but not duration, of vaccine protection

As the efficiency of the malaria vaccine RTS,S (Mosquirix™) has decreased considerably over time, we have looked for a means to prolong the protective effect by manipulating the immune response in a mouse model.

In the course of the immune response, antigen-presenting cells (APC) take up antigens and present them to activate effector T lymphocytes (Teff). Consequently, Teff multiply and produce messenger molecules mediating the destruction of pathogens.
In the course of the immune response, antigen-presenting cells (APC) take up antigens and present them to activate effector T lymphocytes (Teff). Consequently, Teff multiply and produce messenger molecules mediating the destruction of pathogens. However, APC as well as Teff can be inhibited by so-called regulatory T lymphocytes (Treg).

We looked at animals genetically-deficient in so-called regulatory T lymphocytes, a group of cells that inhibit other immune cells. These animals showed a temporarily stronger reaction to both the first and second vaccinations but no development of so-called memory cells, which mediate long-term protection. Immunological memory therefore appears to be regulated by other, yet unknown mechanisms.

 


Espinoza Mora M.R. et al., PLoS One 2014, 9:e104627

Maria del Rosario Espinoza Mora, Christiane Steeg, Susanne Tartz, Volker Heussler, Bernhard Fleischer, Thomas Jacobs and external co-operation partners (see publication)