Search

The aim of this study was to study the role of Th1/Th2 cell-associated chemokines in the formation of hypertrophic scars in rabbit ears. Twenty-six New Zealand white rabbits were used to establish the hypertrophic scar model of rabbit ear and the normal scar model of rabbit's back. Two rabbits were sacrificed on days 0 and 21, 28, 35, 42, 49, 56, and 63 after operation. The specimens were stained with haematoxylin-eosin (HE). Scar elevation index (SEI) was used to detect the expression of 10 chemokines related to Th1/Th2 cells in both scar formation expressions. Real-time polymerase chain reaction (PCR) results showed that two chemokines (CXCL10, CXCL12) were highly expressed during the formation of normal scar, and there was almost no expression during the formation of hypertrophic scar (*P < 0.05). The chemokines (CCL2, CCL3, CCL4, CCL5, CCL7, CCL13, CX3CL1) were almost non-expressed in the formation of normal scars but were expressed for a long time in the formation of hypertrophic scars. The four chemokines, CCL2, CCL4, CCL5, and CX3CL1, maintained a long-term high expression level during the formation of hypertrophic scars (P < 0.01). There were also three chemokines (CCL14, CCL19, CCL21) that were almost undetectable in normal scarring, but there was transiently low-level expression (P < 0.05) only during the peak proliferative phase in proliferative scarring. Th1/Th2 cell-associated chemokines are different in the type, quantity and expression, and maintenance time of rabbit ear hypertrophic scars., (© 2019 Medicalhelplines.com Inc and John Wiley & Sons Ltd.)

Immunological factors play important roles in the occurrence of hypertrophic scars. Imiquimod can be used as an immunosuppressive agent to regulate the function of T-helper (Th) cell subsets Th1 and Th2. In this article, we explored the impact of imiquimod on scar hyperplasia through Th cells. A rabbit ear hypertrophic scar model was built. Four round wounds were cut in each rabbit's ears ventrally with a diameter of 1 cm and bilateral symmetry. All the right ear wounds were treated with 5% imiquimod cream. The blank control group contained all the left ear wounds, which were treated with Vaseline ointment at the same time. Haematoxylin and eosin and Masson staining showed that imiquimod collagen deposition was significantly reduced compared with the control group, scar index (SEI) showed that the proliferative degree reached its peak on the 28th day after operation in blank group, and the degree of hyperplasia was significantly higher than that of the imiquimod group (P < .05). Real-time Polymerase chain reaction results showed that the imiquimod induced the expression of Th2 cell-related chemokines CCL2, CCL3, CCL5, CCL7, and CCL13 at each time point, which were significantly lower than that of the blank control group, and the expressions of Th1 cell-associated chemokines CXCL10 and CXCL12 at each time point was significantly higher than the blank control group (P < .05). Imiquimod can be used to regulate the expression of Th1 and Th2 cell-associated chemokines to control scar hyperplasia., (© 2019 Medicalhelplines.com Inc and John Wiley & Sons Ltd.)