Phagocyte Biology Laboratory

Dr. Bryan Heit, Western University

We are happy to have published two new papers with our collaborators over the past two weeks.

The first paper was published with our collaborators Dr. Warren Lee and Dr. Greg Fairn, both from the┬áSt. Michael’s Hospital in Toronto, where we identified the mechanisms mediating the transport of HDL (good cholesterol) into the brain. Unlike other vascular beds in the body, which allow HDL to slowly “leak” into tissues, the vasculature of the brain is very tight, and materials must be actively transported across. We discovered that the scavenger receptor SR-BI binds to HDL in the blood and then transports the HDL across the blood-brain barrier via a process termed “transcytosis”, in which the cells lining the blood vessels shuttle material from the blood-side to the brain-side inside of small intracellular vesicles. More details can be found in our paper, available free at this link.

Paper on SR-BI and HDL Transport into the Brain

The second paper was published with our collaborator Dr. Dawn Bowdish at McMaster University. This study investigated the recent (hominid) evolution of the phagocytic receptor MARCO which is required for the destruction of many pathogens via phagocytosis. This study demonstrated that MARCO has undergone recent evolution, with some of the newly occurring mutations enhancing the bacteria-clearing capabilities of MARCO. Additional details can be found in the paper, available at this link.

Paper on  the evolution of MARCO