Research interest:  unconventional T cells

Immunity against pathogen-derived proteins and peptides is well understood and applied in vaccines.  The mechanism of immunity against lipids and other non peptidic antigens is less well studied, but potentially as important and applicable in vaccines. 

In humans, unconventional T cells recognizing lipid antigens presented by CD1 molecules become activated during infection with Mycobacterium tuberculosis.  The nature of the antigens and how they are recognized, and the functionality of the reacting T cells has been studied in just a few cases.  The mouse has been widely used as a model animal to study many aspects of the immune system.  However, mice do not have the the CD1a, CD1b, and CD1c molecules that present most known lipid antigens.  Because cattle express a full set of CD1 proteins and is a natural host for mycobacterial infections, unconventional T cells can be studied during these infections and experimental vaccines can be developed and tested in this target species.  Also, we have recently performed comparative analyses of the canine, equine, and porcine CD1 system, as well as other non-classical antigen presenting molecules.  Whave also successfully worked with human T cells that were fresly isolated from blood donations. 

In addition to our work on lipid antigens from Mycobacterium tuberculosis, we are now looking for lipids from unrelated, clinically relevant bacteria that stimulate the CD1 system.  Also, we have provided proof of principle that N-myristoylated peptides can be recognized by the human immune system via presentation by the CD1c protein, which opens the possibility that the CD1 system may also be activated by viral infections.