[The Study of Lipofibroblasts Differentiation of CD90⁺ and CD90⁻ Orbital Fibroblasts Subsets in Patients with TAO].

OBJECTIVE: Divided orbital fibroblasts from patients with thyroid-associated ophthalmopathy (TAO) into CD90⁺ and CD90⁻ subsets respect to surface CD90 expression, then determined whether CD90⁺ and/or CD90⁻ fibroblasts were capable of differentiating into lipofibroblasts.

METHODS: Fibroblasts subset separation into CD90⁺ and CD90⁻ subsets was accomplished by three to four rounds of magnetic bead selection, then treated with 3-isobutyl-1-lmethylxanthine (IBMX), insulin and dexamethasone which was an known inducer of the lipofibroblastic phenotype, then the cells were observed every day to find Lipid droplets. Oil red O staining were conducted at 5 d, 10 d, 15 d, 20 d and 25 d after inducing. The percent of lipofibroblasts were calculated.

RESULTS: The ratio in fibroblast derived from extraocular muscles of differentiating into lipofibroblast is less than from connective/adipose tissue (P < 0.05). The ratio of CD90⁺ fibroblast is less than CD90⁻ fibroblast (P < 0.05). CD90⁺ cells derived from extraocular miscles could not be induced to differentiate into lipofibroblast. The ratio in CD90⁻ fibroblast from connective/adipose tissue is highest (P < 0.05).

CONCLUSION: Orbital fibroblast which has the function of differentiating into lipofibroblast is mainly CD90⁻ connective/adipose tissue.