In vivo demonstration of microvascular pathology by intravital microscopy in experimental chronic graft-versus-host disease: analogy with scleroderma.

Experimental models of chronic graft-versus-host disease have been advocated for studying the pathogenesis of scleroderma. However, microvascular abnormalities have not been documented in these models, whereas in man, cutaneous microvascular pathology (demonstrable by intravital microscopy) is a common feature of scleroderma. In our study scleroderma-like skin disease was evoked by allogeneic bone marrow transplantation in rats. Intravital microscopy of the skin of these animals showed strongly dilated capillaries, resembling the dilated loops in patients. This finding demonstrates that chronic graft-versus-host (scleroderma-like) disease may be pertinent to study the pathogenesis of microvascular injury in scleroderma.