The Pivotal Role Of ??T17 Cells In Relapse Of Psoriasis After Glucocorticoid Treatment

Objective:1.To compare gene expression at skin lesions and??T cells percentage at skin leions and peripheral blood at pro-,pre-treatment and relapse of paoriasis in the process of Glucocorticoid topical therapy.2.To establish the mice model of recurrence of paoriasis after GC topical treatment.3.To detect whether IL-17-producing??T???T17?cells take part in relapse of paoriasis after GC topical treatment.4.To detect whether migration of??T17 cells participate in relapse of paoriasis after GC topical treatment.5.To detect whether CCR6 or CCR2 played a role in??T cells migration during GC treatment.Methods:1.Psoriasis patients were recruited and treated with Halamethasone for 2 weeks.Skin lesions and peripheral blood were taken at pre-,pro-treatment and relapse.RNA-seq was used to detect gene expression at skin lesions,percentages of CD3 and??T cells were detected by flow cytometry.2.C57BL/6 mice were used to establish the mice model of relapse of paoriasis after GC topical treatment,that is,mice were divided into GC treatment group and Vasline control group.Imiquimod?IMQ??10mg/ear/day?was topically applied on mouse ear skin for 3 weeks.From day 6,inflammatory skin was treated with GC?10mg/ear/day?or Vaseline?Vas??10mg/ear/day?as control.Treatment was done on day 21 and mice were allowed to rest for 2 weeks and then re-challenged with IMQ for 7 days.Tcrd^-/-mice were used to follow the same procedure as above.So there were WT/IMQ/Vas group,WT/IMQ/GC group,Tcrd^-/-/IMQ/Vas group,Tcrd^-/-/IMQ/GC group.Measuring ear skin thickness every day.At pro-,pre-treatment and relapse,skin tissue,cervical draining lymph nodes?CLN?and distant inguinal lymph nodes?ILN?were removed to detect percentages of CD3⁺,??,V?4⁺,V?4⁺V4?⁺T cells and Interleukin17?IL-17?level.3.FTY720 was used to inhibit the migration of lymph nodes cells,was injected before IMQ rechallenge.Measuring ear skin thickness every day.Skin tissue,CLN and ILN were removed to detect percentages IL-17-producing CD3⁺,??,V?4⁺,V?4⁺V4?⁺T cells at the time of relapse.4.Ccr6^-/-and Ccr2^-/-mice were used to follow the same procedure as WT mice,mice were divided into WT/IMQ/Vas group,WT/IMQ/GC group,Ccr6^-/-/IMQ/Vas group,Ccr6^-/-/IMQ/GC group,Ccr2^-/-/IMQ/Vas group,Ccr2^-/-/IMQ/GC group.Measuring ear skin thickness every day.Skin tissue,CLN and ILN were removed to detect percentages IL-17-producing CD3⁺,??,V?4⁺,V?4⁺V4?⁺T cells after GC treatment.Results:1.After effective GC topical treatment,PASI score,chemokines gene expression such as CCL20,CCL2 and skin??T cells percentage decreased,peripheral blood??T cells percentage increased.However,at the time of relapse,PASI score,chemokines gene expression such as CCL2 and skin??T cell percentage increased,peripheral blood??T cell percentage decreased.2.Successfully established relapse of paoriasis after GC topical treatment mice model using WT mice,while Tcrd^-/-mice showed no significant difference of psoriasis with no-treated group when relapse.In WT mice treated with GC,percentages of IL17-producing CD3⁺,??,V?4⁺,V?4⁺V4?⁺T cells decreased in skin but increased in CLN and PLN after treatment.However,at the time of relapse,percentages of IL-17-producing CD3⁺,??,V?4⁺,V?4⁺V4?⁺T cells increased in skin but decreased in CLN and PLN.3.After injected with FTY720,mice treated with GC showed allivation of psoriasis when relapse.IL-17-producing CD3⁺,??,V?4⁺,V?4⁺V4?⁺T cells decreased in skin and PLN but increased in CLN.4.Ccr2^-/-mice showed the similar results with WT mice,percentages of IL-17-producing CD3⁺,??,V?4⁺,V?4⁺V4?⁺T cells decreased in skin but increased in CLN and PLN after treatment.However,Ccr6^-/-mice showed allivation of psoriasis when relapse,percentages of IL-17-producing CD3⁺,??,V?4⁺,V?4⁺V4?⁺T cells not only decreased in skin but also in CLN and PLN after treatment.Conclusion:1.Topical GC treatment can alleviate psoriasis effectively,differential chemokine gene expression and change of??T cells percentage at skin lesion and peripheral blood showed migration of??T cells might be the reason of alleviation and relapse of psoriasis after GC treatment.2.Successfully established recurrence of paoriasis after GC topical treatment mice model with WT mice but not Tcrd^-/-mice,showed??T cells play a pivotal role in this model.IL-17-producing??T cells migrate to CLN and ILN after GC treatment,while back home back to skin when relapse.3.It is CCR6 not CCR2has a critical role in the migration of??T cells during GC treatment.