The Molecular Mechanism Of Vascular Endothelial Injury In Patients Witli Preeclampsia

Immunodeficiency,centrometric instability and facial abnormality syndrome(ICF)is an autosomal recessive disease,and thus most ICF patients were born from consanguineous marriage.Based on different disease genes,ICF can be divided into at least five groups(ICF1-4 and ICFX),among which approximately 30% of ICF patients(ICF2)bear non-sense ZBTB24 mutations that generate a pre-mature stop codon.ICF patients often suffer from recurrent respiratory and gastrointestinal infections due to hypogammaglobulinemia,in spite of the normal amount of circulating T/B cells in most patients.However,detailed immunological phenotyping has demonstrated a lack of circulating CD19+CD27+ memory B cells in ICF patients,and moreover,autopsy revealed the absence of germinal center structure in one ICF2 patients.ZBTB24 is ubiquitously expressed in human cells and tissues at m RNA levels,but the highest expressions are detected in B-cell compartment.Our previsous study showed that downregulation of ZBTB24 hampers the cell-cycle progression in human GC-derived B lymphoma Raji cells via upregulating the expression of IRF4 & PRDM1,two transcription factors with essential roles in B-cell differentiation toward memory or plasma cells.These data indicate ZBTB24 may function as a novel transcription factor with a pivotal role in the proliferation and differentiation of human B cells.In the current study,we first generated zbtb24loxp/loxp mice by using CRISPER/CAS9 gene-targeting technology.zbtb24loxp/loxp mice were subsequently crossed with CD19-cre+ mice to generate the B-cell specific zbtb24 knockout CD19-cre+zbtb24loxp/loxp(zbtb24B-CKO)mice.The selective and efficient depletion of zbtb24 in B cells were confirmed at DNA,m RNA and protein levels by normal/quantitative PCR and western blotting.Phenotypic analyses demonstrate that the development of B/T cells in the bone marrow,thymus,peripheral blood and peritoneal cavity are comparable in control or zbtb24B-CKO mice.However,zbtb24B-CKO mice have increased numbers of FOB in the spleen at the expense of MZB cells,albeit that the total numbers of splenic B & T cells are comparable in these mice.Moreover,the baseline levels of Ig G1 is significantly decreased in sera of zbtb24B-CKO mice.Unexpectedly,zbtb24B-CKO mice do not display a general antibody defects upon immunizations with CFA/IFA-OVA or NP-CGG-alum.In contrast,higher levels of antigen-specific Ig G2 b were detected in zbtb24B-CKO mice.Accordingly,zbtb24-deficient B cells produce increased levels of Ig G2 b,Ig G2 c and Ig G3,but not Ig M,Ig G1 & Ig A,upon in vitro stimulations,which can not be attributed to different numbers of FOB and MZB cells as similar results were obtained on purified FOB cells.The comparable expressions of TGF-?RII and T-bet in control and zbtb24-deficient B cells imply that zbtb24 modulates the class-switch recombination(CSR)of anitbodies independent of TGF-?/T-bet.Additionally,zbtb24-deficiency seems to slightly promote the cellular survival in vitro,but has no significantly impact on cellular proliferations upon stimulation with ?-Ig M/?-CD40 or LPS.Together,these data indicate that selective depletion of zbtb24 in CD19+ B cells has no effect on their development in the bone marrow,but disturbs the fate decisions between FOB vs.MZB in the periphery.In contrast to the phenotpyes observed in ICF2 patients,knockout of zbtb24 in murine B cells not only does not blunt the general in-vivo antibody immune responses,but also augments the productions of Ig G2b/2c after immunizations,indicating that the functions of ZBTB24/zbtb24 may differ in humans and mice.