Department of Microbiology and Immunology
3775 University street, Room: 608
Montreal, QC H3A 2B4
Phone: (514) 398-1376
Lab: (514) 398-6386
Fax: (514) 398-7052
connie [dot] krawczyk [at] mcgill [dot] ca (Email)
The immune system possesses the unique capacity to protect an organism from a broad range harmful threats including microbes, parasites and cancer. When misdirected, the immune system is capable of causing disease and suffering through detrimental immunopathological reactions, seen in diseases such as inflammatory and autoimmune conditions. All immune responses are not created equal, and for the maintenance of health, immune responses must be tailored to the type of threat or invasion the body faces. Cells of the innate immune system, such as Dendritic Cells (DCs) are the first responders and play a key role in creating pathogen-specific microenvironments through the generation of secreted mediators including cytokines, chemokines and lipids, and through modification of cell phenotype. T cells, part of the adaptive response, respond to the different activation phenotypes of DCs and other cells of the innate system and in turn differentiate accordingly into distinct effector types, designated as lineages. In addition to “Signal 1”, antigen-specific stimulation, and “Signal 2”, a costimulatory signal, a differentiation signal (“Signal 3”) is required for effective T cell activation and differentiation. The nature of Signal 3 is determined by cells and mediators within the inflammatory microenvironment. We have shown that Signal 3 provided by DCs is a powerful regulator of T cell function not only at the time of activation, but during differentiation and recall responses.
My laboratory is studying the molecular mechanisms by which DCs detect a threat and shape the development of ensuing immune responses. We focus on the molecular mechanisms by which DCs are activated and the how they transmit pathogen-specific information to other components of the immune system.