Cameron Alexander and George Pasparakis at the University report that this first communication occurred by way of sugar groups on the vesicle surface.
The vesicles later transfer information to the cells-in the form of dye molecules.
Complex structures made of many sugar components on the surfaces of cells are the 'language' used for processes such as cell recognition, for example, in the differentiation of tissues or the identification of endogenous cells and foreign invaders.
Scientists would like to be able to use this glycocode to 'address' target cells and to intervene directly in cellular processes to treat diseases or to guide regeneration of damaged tissues.
To understand more about the 'language' of cells, the British researchers took an interesting route: they constructed vesicles, tiny capsules whose outer shell is made of special polymer building blocks.
The polymer chains are equipped with side chains bearing glucose units that wind up being exposed on the vesicle surface.
The researchers brought the vesicles together with bacteria that have glucose-binding proteins on their surface.
The behaviour of the bacteria varies depending on the polymer's composition and the size of the vesicles.
Among the bacteria were some individuals that enter into very strong bonds with large vesicles.
These associated bacteria are then in a position to receive molecular 'information' from the vesicles: dye molecules that were previously placed in the vesicles transferred specifically into the interior of these bacteria.
"Our vesicles can be viewed as simple replicas of living cells that can communicate with real cells by way of the glycocode as well as through signal molecules inside the vesicles," said Alexander.
Possible applications include drug transporters that deliver their cargo to specific target cells, or antibiotic transporters that deliver their toxic load exclusively to infectious agents.
The study is published in the journal Angewandte Chemie International Edition.