Dispatches from the microbiome: membrane vesicles as mediators of bacterial-bacterial and bacterial-human cell communication

The National Institute of General Medical Sciences awarded Cornell University $437,344 on September 1, 2026, under the Biomedical Research and Research Training program (CFDA 93.859) to investigate bacterial extracellular vesicles as mediators of bacterial-bacterial and bacterial-human cell communication.

The research examines how bacterial extracellular vesicles facilitate transport of protein cargo across the mucosal barrier to host cells and distant body sites, with potential applications to understanding microbiome-related disease mechanisms, microbial evolution, and genetic engineering of human-associated microbes. The work expands from the principal investigator's foundational research on horizontal gene transfer to encompass host-microbe interactions and therapeutic applications of vesicles as engineering tools.

Performance runs through June 30, 2031, and is located in Ithaca, New York. Cornell University's Office of Sponsored Programs received the award as the prime recipient.

Abstract

Due to the presence of a thick mucosal barrier, IT is thought that bacteria and human cells mainly interact via diffusible small molecules. However, there is a growing recognition of the role of bacterial extracellular vesicles (bevs) in host-microbe interactions that contribute to disease. Bevs facilitate the transport of larger cargo, most notably proteins, to host cells. My lab and others have found that even though they originate in the GUT, bevs can easily translocate across the mucosa to distant body sites with cell type-specific tropisms, suggesting a mechanism by which bacteria cause extraintestinal manifestations common to microbiome-related disorders. Our research shows that certain protein cargo remains functional after BEV engulfment, suggesting that there are mechanisms by which these proteins can escape the endosome. Whereas my original exposure to bevs was through their potential role in horizontal gene transfer, which served as the foundational research of my lab pre-tenure, we will now expand our focus towards understanding the role of bevs in host- microbe interactions, microbial evolution, and leveraging bevs as an engineering tool to alter genetically intractable human-associated microbes.