The Study Of The Expression And Clinical Significance Of MIF In Pathological Scar And Normal Skin Tissues

ObjectiveAt present the formation mechanism of pathological scar has not been determined, and lack of effective therapeutic methods, Macrophage migration inhibitory factor (MIF) involved in the process of a variety of diseases, It plays a very important role in the tumor, autoimmune diseases, inflammation, angiogenesis and so on, these biological characteristics is similar to keloid。 This experiment is trying to compare the distribution and number of MIF in normal skin、hypertrophic scar、keloid with immunohistochemical method.Method:We collected 40 clinical pathological scar specimens after surgery, it includes 20 hypertrophic scars、20keloids, another 10 samples of the normal skin are used as control group. The samples were fixed by 10% neutral formalin and dehydrated with the gradient alcohol. Embedding the samples with wax and then sliced them into section. Haematoxylin-eosin(HE) staining and immunohistochemistry staining with rabbit MIF polyclonal antibody were performed. The immunohistochemistry staining the positive signal of MIF was brown granules. The average number of five visions which were taken from each section were compared. The same people under same microscope.Result:1. The morphology of HE staining under the microscope: ① Normal skin group can clearly see the epidermal strati fication, corneous layer and the transparent layer fusion, they were eosinophilic, basal cell showed short column, basophil. The dermal papilla is close to the epidermis, epidermal boundary difference really form different parts of the larger, which obviously true skin eyelid boundaries. The dermal papilla is horizontal type arrangement, low, flat, waist and abdomen dermal papilla protruding obvious, the large number, into the epidermal layer, The papillary layer is loose, light colored, net layers thick, dense, it can see more collagen fibers, fibroblasts are distributed in the meantime, the number of small, small hyper chromatic nuclei, normal skin tissue visible sweat and sebaceous glands, hair follicles, and catheter skin appendages. ②The number of basal cell and prickle cells layer of hypertrophic scar are thicker, the connection among the cell is loose, the transparent layer and the cuticle is thin, the dermal papilla is lower, Reticular layer is thick, dense, the collagen could be seen which stained dark, disordered, hyaline degeneration. It can see blood vessels, lymphatic, capillary expansion, inflammatory cells surrounding the vascular distribution, there are a lot of fibroblasts in two layers. ③The epidermis of the keloid is atrophic, in stratum granulosum, stratum lucidum and stratum corneum we could see a thin layer of eosinophilic staining, the cyton of stratum basale and stratum spinosum is large, the number of layer increased. The dermal papilla is looser and flat, reticular layer is thick, the collagen can be see which hyperplasia, Swirl or nodular distribution, stained dark, disordered, and hyaline degeneration which is like patchy structure of homogeneous eosinophilic staining, the coarse fiber bundle dividing the nodules; We can see the inflammatory cell invasived the keloid, the different period fibroblasts of two layers are visible,which has large number and volume,nuclear,much cytoplasm; atretic capillary occlusion or partial occlusion.2. The analysis of the image of immunohistochemical staining of MIF: ①Normal skin:MIF is mainly expressed in the epidermis,dermis tissues expressed less, skin appendage stained dark, hair follicles, sebaceous glands and ducts could see brown granules. ②Hypertrophic scar:The number of the MIF positive granules is bigger than the normal skin, stained dark, MIF is mainly expressed in the epidermis and the fibroblast cell layer of the dermal. ③Keloid:The number of the MIF positive granules is bigger than the normal skin and hypertrophic scar, and high density and wide distribution, stained dark, especially in the fibroblast layer and the surrounding of the atretic capillary. The number of MIF in keloid and hypertrophic scar is bigger than in normal skin, with a statistical significance(P<0.05). The number of MIF in keloid is bigger than in hypertrophic scar, with a statistical significance(P<0.05).Conclusion:MIF were positive expressed in normal skin, hypertrophic scar keloid, the expression of MIF in keloid was significantly higher than that in hypertrophic scar and normal skin, with a statistical significance(P<0.05).It means that the MIF may plays an important role during the pathological scar process. MIF may induce formation of pathological scar by promoting the proliferation of fibroblasts.