So Dietz's team examined patients with stiff skin syndrome and found them to have excessive amounts of fibrillin-1 in the skin. The researchers then sequenced the fibrillin-1 gene in these same patients and found all the stiff skin syndrome mutations clustered in a single region of the fibrillin-1 protein known to interact with neighboring cells. Further examination showed that these mutations prevent fibrillin-1 from interacting with neighboring cells and lead to increased amounts and activity of TGFbeta, which causes excessive collagen outside cells.
The researchers then examined biopsies from patients with scleroderma and found all of the abnormalities seen in stiff skin syndrome. "It appears that fibriillin-1 helps to inform cells about the quality of their surroundings and also provides a mechanism - by concentrating TGFbeta - to induce extra cellular matrix production if the cell senses a deficiency," says Dietz. "A breakdown in signaling coupled with excessive fibrillin-1 and TGFbeta leads to a perfect storm for skin fibrosis in stiff skin syndrome."
While it remains unknown what triggers similar molecular events in scleroderma, these findings do suggest a number of potential treatment strategies, says Dietz.
Source: Johns Hopkins Medical Institutions