Increased chromosome damage in systemic sclerosis skin fibroblasts

Area of Science:

• Dermatology
• Genetics
• Cell Biology

Background:

• Systemic sclerosis (SSc) is an autoimmune disease characterized by fibrosis and vascular abnormalities.
• Chromosomal instability has been implicated in the pathogenesis of various diseases, but its role in SSc is not fully understood.

Purpose of the Study:

• To investigate chromosome damage, specifically micronucleus frequency, in dermal fibroblasts from SSc patients.
• To compare micronucleus frequencies in fibroblasts from affected and non-affected skin of SSc patients with those from healthy controls.

Main Methods:

• Primary dermal fibroblast cultures were established from affected and non-affected skin of SSc patients and from healthy controls.
• Micronucleus (MN) frequency was assessed in cultured fibroblasts, both spontaneously and after exposure to the clastogen bleomycin.
• The number of MN+ cells per 1000 binucleated cells (MN+ cells/1000 BN) was quantified.

Main Results:

• Fibroblasts from both affected and non-affected skin of SSc patients exhibited significantly higher spontaneous micronucleus frequencies compared to controls.
• After bleomycin treatment, fibroblasts from SSc patients (both affected and non-affected skin) showed significantly elevated micronucleus frequencies relative to controls.
• No significant difference in micronucleus frequency was observed between fibroblasts from affected and non-affected skin within SSc patients.

Conclusions:

• Dermal fibroblasts from SSc patients display an increased frequency of both spontaneous and clastogen-induced micronuclei.
• This suggests that increased clastogenesis is a generalized phenomenon in SSc, affecting fibroblasts from clinically distinct skin areas.
• The findings highlight potential chromosomal instability in SSc pathogenesis.