Analysis Of The Efficacy Of Immunosuppressive Treatment In The Treatment Of Activated Phosphoinositide 3-kinase ? Syndrome And T Cell Immune Response In PIK3CD GOF Mice After Infection

PART I ANALYSIS OF THE EFFICACY OF IMMUNOSUPPRESSIVE TREATMENT IN THE TREATMENT OF ACTIVATED PHOSPHOINOSITIDE 3-KINASE ? SYNDROMEObjective: To analyze the clinical and immunological changes of 6 cases of activated phosphoinositide 3-kinase ? syndrome(APDS)type 1 and 1 case of APDS type 2 after treatment with rapamycin or prednisone.To provide functional data for the treatment and pathogenesis of APDS.Methods: To analyze the clinical data and laboratory findings of the APDS patients treated with rapamycin or prednisone who admitted to our hospital during September 2015 to September 2019.The expression of phosphorylated AKT(Ser473)and the mean fluorescence intensity(MFI)of phosphorylated S6 was detected by immunoblot or flow cytometry,the absolute and relative numbers of peripheral lymphocyte subsets were detected by flow cytometry.Results: Six patients with APDS1 had a heterozygous mutation in PIK3 CD c.3061G> A,two of them were treated with rapamycin and 4 were treated with prednisone.One patient with APDS2 treated with prednisone had a heterozygous mutation in PIK3R1 c.1425+1G>A.After the treatment in APDS1 patients,hepatomegaly,splenomegaly and lymphadenopathy were improved,and anemia in one patient were improved.In APDS1 patients treated with rapamycin,the expression of phosphorylated AKT(Ser473)and MFI of phosphorylated S6 were reduced compared to healthy controls,while the APDS1 patients treated with prednisone had a reduction of phosphorylated S6 and an increase of phosphorylated AKT(Ser473).After the treatment with prednisone in APDS2,the hepatomegaly,splenomegaly and lymphadenopathy were significantly improved,and immunoglobulin M was decreased.Compared with healthy control,the MFI of phosphorylated AKT(Ser473)increased while the MFI of phosphorylated S6 decreased.Conclusion: The treatment of APDS includes antibiotic prophylaxis,immunoglobulin replacement therapy,immunosuppressant and hematopoietic stem cell transplantation.This study found that both rapamycin and prednisone have an inhibition on lymphoproliferation in patients with APDS.Prednisone has a significant improvement in autoimmune hemolytic anemia,but to relieve the frequency of infection and maintain the level of immunoglobulins,immunoglobulin replacement therapy is needed.The patients with APDS have a hyperactivation of PI3K,and rapamycin can reduce the activities of AKT and mTOR while prednisone can inhibit mTOR signaling.The targeted inhibitor of p110?may bring new hope for the treatment of APDS.PART II T CELL IMMUNE RESPONSE IN PIK3 CD GOF MICE AFTER INFECTINGObjective: To analyze the T cell immune response in PIK3 CD GOF mice after being infected with lymphocytic choroid plexus meningitis virus(LCMV)and study the effect of hyperactivation of PI3 K on the T cell immune response.To provide experimental basis for the pathogenesis of APDS.Methods: To measure the amounts and function of antigen-specific CD4~+T and CD8~+ T cells,and the T cells were isolated from the spleens of PIK3 CD GOF mice and matched wilt type(WT)mice which were infected with LCMV Armstrong.The amounts and proportions of antigen-specific T cells and cytokines were detected by flow cytometry.Results: After PIK3 CD GOF mice were infected with LCMV Armstrong,as compared with WT,the amounts of antigen-specific CD4~+T cells increased on day 8 and day 15,while it decreased on day 30 and day 45.The expression of cytokines produced by antigen-specific CD4~+T cells such as IFN-?,TNF-? and IL-2 increased on day 8 and day 15,while it decreased on day 45.The amonuts of antigen-specific CD8~+ T cells increased on day 8 while it decreased on day 30 and day 45.The amounts of IFN-? and TNF-? secreted by antigen-specific CD8~+ T cells increased on day 8 and day 15,and decreased on day 30 and day 45.On day 15,the proportion of SLECs in antigen-specific CD8~+ T cells is higher than WT.Conclusion: CD4~+and CD8~+ effector T cells responses present early overproliferation and overactivation and impaired memory establishment after being infected by LCMV.This study proposes the differentiation of memory T cells in PIK3 CD GOF mice is hindered,and the migration occurs during the transformation of effector T cells into memory T cells.The further experiments are needed to explore the effects of extrinsic or intrinsic factors,and to provide more informations on whether recurrent infections in APDS are related to memory T cells disorders.