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Objective@#To study the specific killing effect of CD4 membrane protein targeted chimeric antigen receptor modified T (CAR-T) cell.@*Methods@#The second generation CD4 targeted chimeric antigen receptor containing 4-1BB costimulation domain was insert into lentiviral vector through recombinant DNA technology. Lentivirus was prepared and packaged by 293T cells with four plasmids. Beads activated T cells were transduced with lentivirus and the transduction efficiency was checked with Protein L and flow cytometry. T cell subsets and IFN-γ concentrations were detected with probe-tagged antibody and cytometric bead assay.@*Results@#①The transduction efficiency of activated T cells with prepared lentivirus were 50.0%-70.0%. A subset of CD8+ T cell acquired dim expression of CD4 membrane protein after activation. CD4+T cell and CD8+CD4dim T cell were gradually killed by CD4 targeted CAR-T post lentivirus transduction. ②The kill efficacy of CD4 targeted CAR-T cell and control T cell toward KARPAS 299 T cell at an E∶T ratio of 8∶1 for 24 h was (96.9±2.1)% and (11.2±3.1)%, CAR-T cell has a higher killing efficacy than control T cell (t=7.137, P=0.028). The IFN-γ concentrations in culture supernatant of CAR-T cell with K562-CD4 cell, CAR-T cell with K562 cell and CAR-T cell alone were (15 648±2 168), (1 978±354) and (1 785±268) pg/ml, CAR-T cell cocultured with K562-CD4 cell produced more IFN-γ than the other two controls (P<0.01).@*Conclusions@#CD4 targeted CAR-T has an immunophenotype of CD8+CD4-T cell. CD4 targeted CAR-T cell has killing efficacy toward normal CD4+T cell and CD4+T lymphoma cell. CD4 targeted CAR-T cell also has a killing efficacy toward CD4dim target cell.
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<p><b>OBJECTIVE</b>To detect structural changes in the brain in fetuses with agenesis of the corpus callosum (ACC) and holoprosencephaly (HPE) in the first trimester.</p><p><b>METHODS</b>The ultrasound data were analyzed retrospectively in 620 normal singleton fetuses between 11 and 13(+6) gestational weeks, 5 fetuses diagnosed to have ACC, and 13 fetuses with HPE. The midbrain diameter (MD) and falx diameter (FD) were measured and their ratio (MD/FD) was calculated for comparative analysis.</p><p><b>RESULTS</b>No significant difference was found in the MD, FD, and MD/FD ratio between fetuses with ACC and HPE (P>0.05). Compared to the normal fetuses, all the fetuses with ACC and HPE showed significantly increased mean MD and MD/FD ratio (P<0.05); 4 (80%) fetuses with ACC and 11 (84.6%) with HPE had a reduced FD. All the fetuses with ACC and HPE had MD/FD ratios greater than 1, which were below 1 in all the normal fetuses.</p><p><b>CONCLUSION</b>In the first trimester, fetuses with ACC and HPE have measurable abnormalities in the midbrain and falx area of the brain, and these changes, represented by abnormal midsagittal MD, FD and their ratio, can be of value in detecting ACC or HPE in fetuses in the first trimester.</p>
Subject(s)
Female , Humans , Pregnancy , Agenesis of Corpus Callosum , Diagnosis , Corpus Callosum , Diagnostic Imaging , Fetus , Gestational Age , Pregnancy Trimester, First , Retrospective Studies , Ultrasonography, PrenatalABSTRACT
Viral infections remain the common cause of morbidity and mortality in immunocompromised patients receiving allogeneic hematopoietic stem cell transplantation (allo-HSCT).Virus antigens can be recognized by cytotoxic T-lymphocytes (CTL) in the context of HLA class Ⅰ molecules.T-cell-based immunotherapies are now being included in the clinical practice of transplant recipients to prevent and treat viral infections and complications associated with CMV,AdV and EBV.Here,the current status and future feasibility of CTL immunotherapy for virus infections after allo-HSCT are discussed.
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ObjcetiveTo study the chimerism status ot bone marrow mesenchymal stem cells (BMSC) following double-unit cord blood stem cell transplantation (DCBT).MethodsBone marrow mononuclear cells were isolated by ficoll density gradient centrifugation from the patient following DCBT and healthy donors.After cultured for about 20 days,BMSC surface makers,the ability to differentiate into adipocytes and osteoblast and the expression of hematopoietic and immune molecules were detected,moreover,chimerism status of BMSC were also evaluated by STR-PCR.ResultsMSC derived from the patient were similar to normal adult BMSC in morphology,surface and differentiation ability.Besides,MSC from the patient can express a variety of hematopoietic and immune molecules normally.The results of STR-PCR showed that the patient demonstrated complete donor chimerism,hematopoiesis in BM and PB were from a single unit cord blood (donor chimerism was 96.4％ and 95.7％,respectively).But the predominant cord blood chimerism of BMSC was 5.4％,the remaining part was from the patient himself.ConclusionSustained hematopoiesis was derived from a single unit cord blood following DCBT.The majority of BMSC were origin from host tissue,mixed chimerism donor part of MSC stemed from the engrafted unit of cord blood.
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BACKGROUND: Tissue engineering method has been employed to recover cartilage defect and overcome many traditional shortages.OBJECTIVE: In vitro marrow mesenchymal stem cells (MSCs) of adult rat was induced to differentiate into chondrocyte phenotype so as to probe into the feasibility of MSCs to be cartilage seed cell in tissue engineering.DESIGN: Completely randomized design and controlled experimental study.SETTING: Department of Histology and Embryology, and Department of Neurobiology, Harbin Medical University MATERIALS: Six Wistar rats of either gender, cleanness grade, were provided by Experimental Animal Center, Affiliated Second Hospital, Harbin Medical University. Permission number of experimental animal production was SCXK(black) 20020002.METHODS: The MSCs of the second generation adult rat was taken and divided into test group and control group. The test group was induced with serum free and control group was induced with 10% fetal calf serum. Collagen type Ⅱ immunohistochemical staining, toluidine blue staining was performed to detect differentiation.MAIN OUTCOME MEASURES: Identification of chondrocyte, comparison of the positive rate of Collagen type Ⅱ immunohistochemical staining at different induction time point.RESULTS: Induced MSCs had identical characteristic to the chondrocyte.CONCLUSION: In vitro culture can induce MSCs to differentiate directly to chondrocyte-like cell. The results suggest that it is feasible to use MSCs as seed cells in the cartilage tissue engineering.
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We performed a set of explorations and reform on teaching Histology and Embryology in English to improve the teaching quality.This article summarized some experiences of teachers training,preparation before class the use of the teaching method,and selection of suitable textbook and examinations.