The effect of CD07813 in the transplant model of psoriasis; in which a psoriatic lesion is induced in non-lesional skin transplanted onto immune-deficient (BNX) mice by injecting activated peripheral blood cells intra-dermally into the transplant. RD/10/15700

Small (5 mm diameter) biopsies from healthy skin of psoriasis patients
(volunteers) will be transplanted onto immune-deficient mice. A psoriasis
lesion will be induced in the transplant by injecting the volunteers
super-antigen activated white blood cells into the transplant. One week later
we will start treating the transplants topically with the various test
substances.

In previous projects a number of compounds were tested that had a positive
effect in the transplant model of psoriasis. However, it proved difficult to
prepare formulations that were stable enough to use in clinical studies. A new
compound (CD07813) has now been developed (a modification of 1of the previous
chemicals) which is active in vitro and also has good pharmaceutical
properties. this will be tested in the mouse psoriasis model.

Volunteers (psoriasis patients) will donate 3 x 0.5 mm skin biopsies and 27 ml
blood. The skin to be removed (non-involved skin) will be disinfected and the
anaesthetised by injecting it with xylocaine. Three 0.5 mm diameter skin
biopsies will then be taken and the wound sites closed using stitches. The
wounds will be covered with a plaster and kept dry for 24 hrs. After 7 days the
stitches will be removed.

The risks associated with the research are small, possible small scars or
discolouration at the biopsy site.