Dendritic cells in psoriasis and effects of efalizumab

DESCRIPTION (provided by applicant): CANDIDATE: I am a dermatologist (MD PhD) and my broad career goal is to be an independent physician scientist in human translational skin research, particularly in the area of psoriasis. I am proposing to become a multi-disciplinary patient-oriented researcher, with an excellent grasp of a number of technologies, which will allow me to investigate therapeutic, mechanistic and pathologic questions appropriately and deeply. ENVIRONMENT: Rockefeller University is a world-renowned institution with a rich history of bench-bedside research. It provides an ideal environment to carry out this type of clinical research with a dedicated GCRC-funded research hospital, outstanding laboratories, excellent core facilities and equipment, an innovative Clinical Scholars Program for translational research trainees, and several inspiring lecture and seminar programs. There is no fee-for-service medicine at Rockefeller University, so I can dedicate 100% of my time to this career development plan. RESEARCH PROJECT: Psoriasis offers an excellent model of type 1 autoimmunity, and there is no ideal animal model of psoriasis to study. In the context of a clinical trial with efalizumab (anti-CD11a) for psoriasis, we identified a new type of cutaneous dendritic cell (DC) (CD11c+, HLA-DR+, CD86+, CD40+), which constitutes the most abundant type of leukocyte in psoriasis lesions. It also expresses TNF and iNOS, so these cells may be the human equivalent of recently described murine TNF- and indicible nitric oxide synthase (iNOS)-producing (TIP)-DCs. I plan to begin basic characterization of complex DC subsets that exist in blood and skin of humans, using efalizumab as a tool to modulate psoriasis disease activity, so that the contribution of different DC subsets to disease pathogenesis can be better refined. Furthermore, I will determine the extent to which efalizumab has direct effects on growth, differentiation and activation of DCs versus indirect effects through T cell modulation.