Philippa MarrackProfessor

We study lymphocytes, the cells which recognize that an infection is occurring in the body. Amongst these, we are particularly interested in T cells. They recognize infections in an unexpected way, by reacting with fragments of the infection bound to special proteins of the body, the MHC proteins. We are trying to find out how T cells learn to react in this fashion. We are also interested in the ways in which T cells are prevented from attacking MHC proteins bound to fragments of their own host. In most people such attack is efficiently avoided. However, in some individuals T cells do react in this way, and this event causes autoimmune diseases such as rheumatoid arthritis and juvenile diabetes. Our recent experiments suggest that the diseases occur because the peptide fragments involved are binding to MHC in an unexpected way. B cells, the cells that produce antibodies, are also involved in autoimmune disease.. We have recently found an unusual population of B cells that might be involved in the process. The power of the immune response is harnessed in vaccines, vaccines act by inducing T and B cell memory to protect us against invading organisms. We study how this is accomplished, with the hope that this understanding will help us design better vaccines.