Effects Of Interleukin-22 On The Expression Of CCL28 In HaCaT Cells

Psoriasis is a polygenic hereditary inflammatory skin disease caused by a combination of environmental and genetic factors.It is one of the most common chronic diseases in dermatology that affects the physical and mental health of patients and imposes a heavy financial burden on patients and society.Clinically,psoriasis is often divided into the following four types: psoriasis vulgaris,pustular psoriasis,psoriatic arthritis,and erythrodermic psoriasis.The etiology and pathogenesis of psoriasis have not been defined.Currently,it is considered that psoriasis is a T-cell-mediated immune-mediated disease that targets human epidermal keratinocytes.Th22 is the most advanced T cell subgroup in the research on psoriasis.IL-22 is a member of the IL-10 family.Th1 cells,Th17 cells,and Th22 cells all secrete the cytokine IL-22.Domestic and foreign studies indicated that the expression of IL-22 in peripheral blood and skin tissue of patients with psoriasis is significantly higher than that of normal people.At the same time,studies have also shown that the expression of IL-22 was in positive correlation with the severity of psoriasis.After treatment of psoriasis patients,not only the peripheral blood of patients but also the expression of IL-22 in the skin lesions were lower than that before treatment.This suggests that IL-22 plays an important role in the pathogenesis of psoriasis.CCL28 is also known as mucosae-associated epithelial chemokine(MEC).It is a chemokine of a CC family,first reported by Pan et al in 2000.The gene of CCL28 is located on the long arm of human chromosome 5 and is mainly expressed in epithelial cells of mucosal tissues,such as salivary glands,breasts,respiratory tract,and reproductive tract.Foreign studies have shown that the expression of CCL28 in serum and skin lesions of patients with psoriasis is significantly higher than that in normal people.CCL28 has two receptors,CCR3 and CCR10.There are many ligands for CCR3.Common ones are chemokine 5,chemokine 8,chemokine 7,and so on.But there are only two types of CCR10 receptors,CCL27 and CCL28.It is worth exploring that CCL27 and CCL28 have a high degree of homology.Our previous studies showed that existing studies have shown that IL-22 can promote the expression of CCL27 and thus affect the proliferation and differentiation of keratinocytes,and that IL-22 may regulate its biological effects through MAPK-ERK1 / 2 pathway.Thus we speculated that IL-22 may affect the expression of human epidermal keratinocyte CCL28 through the MAPK-ERK1 / 2 pathway in the body of patients with psoriasis,thereby affecting the proliferation and differentiation of human keratinocytes.However,no research has been reported on the corealtion between IL-22 and CCL28.Therefore,in this experiment,we examined the effect of IL-22 on the expression of CCL28 in HaCaT cells by treating HaCaT cells with IL-22 and MAPK-ERK1 / 2 pathway blockers.On the other hand,We injected IL-22 subcutaneously into a mouse model of 5% imiquimod induced psoriatic lesions,and detected the expression of CCL28 in the lesions.Object:In this study,the expression of CCL28 in the skin tissues of patients with psoriasis and healthy people was detected by immunohistochemistry.Then through cell experiments and animal experiments to explore the effect of IL-22 on the expression of CCL28 in HaCaT cells and psoriatic-like mouse model skin tissue,so as to explore the role of IL-22 / CCL28 axis in the pathogenesis of psoriasis.Methods:1.Twelve skin tissue samples from patients with psoriasis and 12 healthy human skin tissue samples were taken.The specimens of patients with psoriasis are from the Department of Dermatology and Pathology of the General Hospital of Tianjin Medical University.These patients have been diagnosed with psoriasis based on clinical and pathological conditions.Healthy human skin tissue specimens are derived from normal skin tissue cut by surgery in the Department of Plastic and Aesthetic Medicine,General Hospital of Tianjin Medical University.IHC method was used to detect the expression of CCL28 in the skin tissues of normal and psoriasis patients.2.The cultured HaCaT cells were divided into 6 groups and given the following treatments: PBS control group,12.5ug / L IL-22 group,25 ug / L IL-22 group,50 ug / L IL-22 group,100 ug / L IL-22 group and blocker group(50ug / L IL-22 + PD98059).The blocker group was administered in the following way: 2ul MAPK-ERK1 / 2 blocker PD98059 was first added to the culture well so that the final solubility of the well was 50 umol / L,and then placed in a cell incubator at 37 ° C.2 hours later,add IL-22 to the empty so that the final concentration of IL-22 is 50 ug / L,and then place it in a cell incubator at 37 ° C for culture.After 24 hours,the position of CCL28 in HaCaT cells was detected by immunofluorescence.HaCaT cell proliferation was detected by CCK8 method.Total protein and m RNA of HaCaT cells were extracted after treatment.The expression of CCL28 in HaCaT cells was detected by Western Blot,ELISA and RT-PCR.SPSS 21.0 software was used for one-way analysis of variance and Dunnett-t test.P <0.05 was considered statistically significant.3.Female BALB / c mice were randomly divided into four groups.Two groups of the experimental group were treated with imiquimod cream on the back skin,and the other two groups of control group were treated with vaseline on the back skin.Malemice were grouped and treated in the same way.The mice in the experimental group were successfully modeled 5 days later and developed psoriasis-like skin lesions.After the successful modeling,one group was randomly selected from the experimental group and the control group,and mouse-derived IL-22 was injected into the skin tissue of the back of the selected group of mice.After 48 hours,the mice were treated with a decapitation method,and the back skin tissue was removed.The expression of CCL28 in the skin tissue of each group was detected by immunohistochemistry.Results:1.Human epidermal tissue immunohistochemical detection showed that CCL28 protein was mainly expressed in the cytoplasm of human epidermal cells.In normal human skin,CCL28 is mainly expressed in the basal layer,and the other layers are expressed in a small amount,and the expression is weak.While,in the epidermal tissue of psoriasis patients,CCL28 is widely expressed,and the expression intensity is significantly higher than that of normal skin.2.IL-22 can not only promote the proliferation of HaCaT cells,but also promote the expression of CCL28 in HaCaT cells.This promotion appears concentration-dependent.That is,as the concentration of IL-22 increases,the proliferation rate of HaCaT cells will accelerate.The expression of CCL28 will also increase.On the other hand,after adding MAPK-ERK1 / 2 pathway blocker PD98059,not only the proliferation of HaCaT cells but also the expression of CCL28 in HaCaT cells were reduced compared to the 50 ug / L IL-22 group.3.Using 5% imiquimod can successfully induce psoriasis-like skin lesions in mice.Subcutaneous injection of IL-22 in the back of mice can increase the expression of CCL28 in the skin tissues of normal mice and psoriatic lesions.Conclusions:1.The expression of CCL28 in the epidermal tissue of patients with psoriasis was significantly higher than that in normal human skin tissue.2.IL-22 can promote the proliferation of HaCaT cells and the expression of CCL28 in HaCaT cells in a concentration-dependent manner,and MAPK-ERK1 / 2 pathway blockers can block this promotion.3.IL-22 can increase the expression of CCL28 in the skin tissue of normal mice and the skin tissue of mice with psoriasis-like lesions.In summary,the IL-22 / CCL28 axis may serve as a target for the treatment of psoriasis,providing a new direction for the treatment of patients with psoriasis.