The Correlation Analysis Between Fibroblasts CD90 Expression And The Pathogenesis Of Hypertrophic Scars

OBJECTIVE:To further explore the pathogenesis of hypertrophic scars, the differences of CD90 expression and biological characteristics of fibroblasts in abnormal scars and normal skin were investigated. CD90 expression of fibroblasts in abnormal scars and normal skin was undertaken by immunohistochemistry. The expression of CD90 and its correlation with the proliferation, synthesis and contraction of fibroblasts was analyzed.METHODS:1. The 18 hypertrophic scars from operation were divided into hypertrophic scar group(HTS, n=18), scar junction group(n=18) and normal skin group(NS, n=18). 2. Two pathologists checked all the tissue sections with haematoxylin-eosin dyeing in order to support the clinical diagnosis. The paraffin block of tissue chips were consisted of one core taken from each of the hypertrophic scar group, scar junction group and normal skin group. Each paraffin block of tissue chips including 54 points of the tissue was put into array as 9×6. 3. Cut the paraffin block of tissue chips into five pieces of tissue chips. The specimens of tissue chips were detected for the expression of CD90,TGF-β₁,α-SMA,Collagen-I and III by immunohistochemical staining. All the results were analyzed statistically. 4. The correlation of CD90 expression with that of TGF-β₁,α-SMA,Collagen-I and III was determined by means of statistical analysis.RESULTS:1. The tissue chips containing hypertrophic scars were successfully constructed, and the correlation analysis of multiple factors got well effect in immunohistochemical detection. 2. Immunohistochemistry showed that 11 cases had CD90 positive phenotypic fibroblasts in 18 cases of hypertrophic scar group, 8 cases in scar junction group, and 3 cases in normal skin group. They had a significantly statistical difference (P<0.05) in comparison with normal skin. 3. TGF-β₁ andα-SMA rarely expressed in normal skin, but they had varied expressions in hypertrophic scars and scar junction. They had a significantly statistical difference (P<0.05) in comparison with normal skin. 4. The total contents of collagen in tissue of hypertrophic scars and scar junction were very close, all were higher than those in normal skin. Most hypertrophic scars showed as collagen-I, while most nomal skin showed as collagen-III. 5. Statistical analysis could verify the correlation of CD90 expression with that of TGF-β₁ andα-SMA.CONCLUSIONS: 1. The tissue chips are high efficiency and well controlled in quality for multiple factors'investigation. It can be further used in the study of hypertrophic scars. 2. Fibroblasts expressing CD90 in hypertrophic scars might be some phenotypes specifically related to scar formation. 3. The findings of increased TGF-β₁ indicated that TGF-β₁ may participate and play an important role in the formation of hypertrophic scars, so it was of great clinical significance for the prevention and treatment of hypertrophic scars. 4. The expression ofα-SMA can be induced by TGF-β₁ in hypertrophic scars. 5. The variety of composition and distribution of collagen I/III in the hypertrophic scars plays an important role in the formation and development of hypertrophic scars. 6. The expression of CD90 have correlation with that of TGF-β₁ andα-SMA, they might have some synergistic relationships in hypertrophic scarring.