Objective To generate and characterize natural killer cell (NK cell)-conditional Cd226 gene knockout mice using Cre-loxP technology, and to explore the role of CD226 on NK cells in alleviating intestinal inflammation in a murine model of ulcerative colitis (UC). Methods NK cell-conditional Cd226 gene knockout mice were generated by crossing loxP-flanked Cd226 mice with Ncr1-Cre mice via the Cre-loxP system. Polymerase chain reaction (PCR) and agarose gel electrophoresis were used for genotyping. A UC model was established by dextran sulfate sodium (DSS) induction. Flow cytometry was performed to analyze CD226 expression levels on NK cells and the infiltration of related immune cells in colon tissues. Hematoxylin-eosin (HE) staining was performed to assess the degree of colonic inflammation. Results DNA gel electrophoresis and flow cytometry confirmed the successful generation of NK cell-specific Cd226 knockout mice. After conditional knockout of Cd226 in NK cells, inflammation in the UC mouse model was alleviated. Flow cytometry results showed a reduced proportion of NK cells in peripheral blood and the colon lamina propria, while HE staining demonstrated attenuated inflammatory responses. Conclusion Specific knockout of Cd226 in NK cells mitigates intestinal inflammation in UC mice by reducing NK cell numbers and inhibiting their pro-inflammatory functions.
Animals ; Colitis, Ulcerative/pathology* ; Killer Cells, Natural/metabolism* ; Mice, Knockout ; T Lineage-Specific Activation Antigen 1 ; Antigens, Differentiation, T-Lymphocyte/genetics* ; Mice ; Disease Models, Animal ; Mice, Inbred C57BL ; Male

Analysis of the T-cell receptor (TCR) repertoire of innate CD4+ T cells selected by major histocompatibility complex (MHC) class II-dependent thymocyte-thymocyte (T-T) interaction (T-T CD4+ T cells) is essential for predicting the characteristics of the antigens that bind to these T cells and for distinguishing T-T CD4+ T cells from other types of innate T cells. Using the TCRmini Tg mouse model, we show that the repertoire of TCRalpha chains in T-T CD4+ T cells was extremely diverse, in contrast to the repertoires previously described for other types of innate T cells. The TCRalpha chain sequences significantly overlapped between T-T CD4+ T cells and conventional CD4+ T cells in the thymus and spleen. However, the diversity of the TCRalpha repertoire of T-T CD4+ T cells seemed to be restricted compared with that of conventional CD4+ T cells. Interestingly, the frequency of the parental OT-II TCRalpha chains was significantly reduced in the process of T-T interaction. This diverse and shifted repertoire in T-T CD4+ T cells has biological relevance in terms of defense against diverse pathogens and a possible regulatory role during peripheral T-T interaction.
Amino Acid Sequence ; Animals ; Antigens, Surface/metabolism ; CD4-Positive T-Lymphocytes/cytology/*immunology/*metabolism ; Cell Communication ; Cell Differentiation/genetics/immunology ; Clonal Evolution ; Histocompatibility Antigens Class II/*immunology ; *Immunity, Innate ; Immunophenotyping ; Lymphocyte Count ; Mice ; Mice, Knockout ; Mice, Transgenic ; Peptide Fragments/chemistry ; Phenotype ; Receptors, Antigen, T-Cell/chemistry/*genetics/metabolism ; Receptors, Antigen, T-Cell, alpha-beta/chemistry/genetics ; Spleen/cytology ; Thymocytes/cytology/immunology/metabolism

OBJECTIVETo construct the expression vector pLCK-CD69-IRES-EGFP that contains mouse cell surface activation protein CD69 and enhanced green fluorescent protein(EGFP),and to generate CD69 transgenic mice based on this vector.

METHODSFirst, RNA was extracted from mouse lung tissue and cDNA was synthesized via reverse transcription. PCR primer was designed through the PubMed searching, then mouse CD69 DNA fragment was amplified with PCR. Second, this DNA fragment was subcloned to the pInsulater-LCK-IRES-EGFP plasmid and constructed the transgenic vector after the verification of nucleotide sequence. Third, the expression vector was then transfected into 293 T cells and its expression in 293 T cells was observed under fluorescence microscope. Last, microinjection was performed to transfer the expression vector pLCK-CD69-IRES-EGFP into fertilized eggs, which were implanted into pseudo-pregnant recipient mice. After birth the tail samples of the pups were obtained for the purpose of genotyping to determine the transgenic founders. Fluorescence microscope and flow cytometer were used to measure the expression of CD69 on cells.

RESULTSThe construction of the expression vector pLCK-CD69-IRES-EGFP was verified by enzyme digestion and DNA sequencing. The transfected 293 T cell showed expression of the protein under fluorescence microscope. Identification of PCR for the tail tissue of the pups confirmed the present of CD69 transgene and resting lymphocytes demonstrated the expression of CD69.

CONCLUSIONThe construction of expression vector pLCK-CD69-IRES-EGFP and generation of CD69 transgenic mice have been successfully processed, which lays a foundation of the solid pattern studies in inflammatory diseases.

Animals ; Antigens, CD ; genetics ; Antigens, Differentiation, T-Lymphocyte ; genetics ; DNA, Complementary ; Genetic Vectors ; Genotype ; Green Fluorescent Proteins ; genetics ; Lectins, C-Type ; genetics ; Mice ; Mice, Transgenic ; Plasmids ; Polymerase Chain Reaction ; Sequence Analysis, DNA ; Transfection

OBJECTIVETo investigate the expression profile of immune effector molecules in peripheral natural killer cells (NK) in patients with chronic hepatitis virus B.

METHODSAccording to the infection status, patients were divided into four experiment groups: normal hepatic function and high HBV DNA level group, normal hepatic function and low HBV DNA level group, abnormal hepatic function and high HBV DNA level group and abnormal hepatic function and low HBV DNA level group. The expression of perforin (PF), granzyme B (Gr B), granulysin (GNLY), tumor necrosis factor alpha (TNFa) and interferon gamma (IFNr) in NK cells were detected by flow cytometer.

RESULTSCompared with control group (31.50%+/-27.64%), the expression of GNLY was significantly increased in normal hepatic function and high HBV DNA level group (59.74%+/-30.82%) and normal hepatic function and low HBV DNA level group (61.89%+/-33.30%); the expression of IFNr in normal hepatic function and high HBV DNA level group (39.89%+/-21.30%) and abnormal hepatic function and high HBV DNA level group (37.54%+/-18.79%) was lower than that in normal control group (57.38%+/-23.69%); the expression of PF, GrB, GNLY in abnormal hepatic function and high HBV DNA level group (35.47%+/-29.64%, 66.55%+/-22.92%, 42.03%+/-33.17%) was lower than that in normal hepatic function and high HBV DNA level group (56.98%+/-38.34%, 81.53%+/-19.58%, 59.74%+/-30.82%) and normal hepatic function and low HBV DNA level groups (62.95%+/-31.98%, 84.51%+/-14.57%, 61.89%+/-33.3%); there were positive correlations between ef PF, Gr B, GNLY, TNFa, and IFNr.

CONCLUSIONThe expression of IFNr in NK cells from patients with high HBV DNA replication level is lower than that in normal control group; the expression of PF, Gr B and GNLY in NK cells from patients with normal hepatic function is higher than that in NK cells from patients with abnormal hepatic function.

Adolescent ; Adult ; Antigens, Differentiation, T-Lymphocyte ; metabolism ; Case-Control Studies ; Cytokines ; metabolism ; DNA, Viral ; blood ; Female ; Flow Cytometry ; Gene Expression Profiling ; Granzymes ; metabolism ; Hepatitis B virus ; genetics ; immunology ; Hepatitis B, Chronic ; immunology ; pathology ; Humans ; Killer Cells, Natural ; immunology ; metabolism ; Liver Function Tests ; Male ; Middle Aged ; Perforin ; metabolism ; Virus Replication ; Young Adult

The G13 domain derived from granulysin shows high antimicrobial activities against Gram-positive and Gram-negative bacteria but does not lyse Jurkat cells or liposomes. To explore a new approach for high expression of the G13 domain, we fused the sequence encoding G13 to thioredoxin (Trx) gene to construct the recombinant expression vector (pThioHisA-G13). A cyanogen bromide (CNBr) cleavage site was introduced between the Trx and G13 to facilitate final release of the recombinant G13. The recombinant expression vector, pThioHisA-G13, was transformed into E. coli BL21 (DE3). Upon induction by IPTG Trx-G13 fusion protein was expressed and took the form of inclusion bodies counting 58% (W/W) of total cellular proteins. The inclusion body was solved by urea (8 mol/L) and then cleaved by CNBr. We purified the recombinant peptide G13 by one-step cation exchange chromatography. Results of agarose diffuse assay analysis indicated that the recombinant G13 exhibited antibacterial activity. The procedure described in this study will provide a reliable and simple method for highly efficient production of some cationic antimicrobial peptides.
Anti-Infective Agents ; metabolism ; Antigens, Differentiation, T-Lymphocyte ; genetics ; Cyanogen Bromide ; pharmacology ; Escherichia coli ; genetics ; metabolism ; GTP-Binding Protein alpha Subunits, G12-G13 ; biosynthesis ; genetics ; Inclusion Bodies ; metabolism ; Protein Structure, Tertiary ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Thioredoxins ; genetics ; Transfection

OBJECTIVETo observe the change of activation and proliferation ability of rat T-lymphocytes after suppress ICOS gene expression by RNA interference.

METHODSFour interference sites targeting at rat ICOS gene were designed and four pairs of oligonucleotide fragments were cloned into the pSilencer 4.1-CMV neo plasmid vectors then transfected into rat lymphocytes with cationic liposome. The expression of mRNA and protein of ICOS was detected by RT-PCR and flow cytometry. The alteration of lymphocyte proliferation ability was evaluated by mix lymphocyte reaction, and the secretion levels of IFN-gamma and IL-4 were measured by ELISA procedure.

RESULTSAfter transfection, the expression of mRNA and protein of ICOS in test groups were lower than that in control groups (P < 0.05). The ability of T-lymphocytes in proliferation was poor and the levels of IFN-gamma and IL-4 were reduced with ICOS gene shut down.

CONCLUSIONSRNA interference plasmid vector can suppress ICOS expression in rat T-lymphocytes significantly, and it may be useful for further study on transplantation immunity tolerance.

Animals ; Antigens, Differentiation, T-Lymphocyte ; genetics ; metabolism ; Cell Proliferation ; Cells, Cultured ; Female ; Genetic Vectors ; Inducible T-Cell Co-Stimulator Protein ; Interferon-gamma ; metabolism ; Interleukin-4 ; metabolism ; Lymphocyte Activation ; Male ; RNA Interference ; Rats ; Rats, Sprague-Dawley ; T-Lymphocytes ; immunology ; metabolism ; Transfection

Cytomegalovirus (CMV) infection is a dangerous complication in patients with chronic graft versus host disease (cGVHD). CMV-specific immunity depends on the activity of T cells. This study was aimed to investigate the effect of CMV pp65 gene modified dendritic cells (DCs) on activation of autologous T cells. Lentivirus system was utilized to introduce the CMV full-length pp65 gene into mouse DCs; CpG-DNA was used to induce mature DCs; flow cytometry and immunofluorescence were used to determine the expression of antigen and IFNgamma in T lymphocytes. The results showed that the DCs were infected with lentivirus at a multiplicity of infection (MOI) of 50 with optimal infectious efficiency of 30%-40%; mature DCs expressing pp65 gene could stimulate autologous naive T cells to express CD69 specifically; mature DCs expressing PP65 could stimulate autologous CD4+ or CD8+ T cells to produce IFNgamma. It is concluded that CMV pp65-modified and CpG-DNA-induced mature DCs can activate CMV-specific T lymphocytes in vitro.
Animals ; Antigens, CD ; genetics ; metabolism ; Antigens, Differentiation, T-Lymphocyte ; genetics ; metabolism ; Antigens, Viral ; immunology ; CD4-Positive T-Lymphocytes ; immunology ; CD8-Positive T-Lymphocytes ; immunology ; CpG Islands ; genetics ; Cytomegalovirus ; immunology ; DNA ; genetics ; Dendritic Cells ; cytology ; immunology ; metabolism ; Humans ; Interferon-gamma ; genetics ; metabolism ; Lectins, C-Type ; Lentivirus ; genetics ; metabolism ; Mice ; Phosphoproteins ; genetics ; metabolism ; Viral Matrix Proteins ; genetics ; metabolism

OBJECTIVETo explore the effects of adenovirus vector-mediated gene transfer of ICOSIg fusion protein on experimental autoimmune myocarditis (EAM) in Lewis rats.

METHODSExpression vector containing ICOSIg (p-Adeno-ICOSIg) was constructed by fusion of human ICOS and IgGFc segment. Adenovirus vector was digested by PacI enzyme and transfected into HEK 293 cells. Adenovirus expressing ICOSIg was produced. EGFP was constructed into adenovirus vector and used as control. EAM was induced in Lewis rats by injection of porcine cardiac myosin. All immunized Lewis rats were divided into 4 groups. Group A (n = 15) and B (n = 15) received adenovirus containing ICOSIg on day 0 and day 14 respectively to study the effects of costimulatory molecules gene therapy on T cell activation and inflammation; group C (n = 10) and group D (n = 10) received adenovirus containing EGFP on day 0 and day 14 respectively as controls. Group E (n = 10) was normal controls that did not receive immunization. On day 28, all rats were killed after echocardiography examination. Histopathological examination was performed to observe myocardial inflammation. Protein levels of ICOS, ICOSL, B7-1 and B7-2 were detected by Western blot. INF-gamma, IL-2 and IL-4 mRNA were determined by realtime RT-PCR.

RESULTSOn day 28, cardiac function was significantly improved and myocardial inflammation significantly attenuated in group B compared to group A, C and D (all P < 0.05). B7-1 expression at protein level was significantly lower in group B than that of group C (P < 0.05). ICOS and ICOSL expressions at protein level were significantly decreased in both group A and B compared with group C and D (P < 0.05). IFN-gamma mRNA level significantly decreased and IL-4 mRNA significantly increased in group A and B compared to group C and D (P < 0.05).

CONCLUSIONSBlockade of costimulatory pathway with gene therapy of ICOSIg alleviated autoimmune inflammatory damage and improved cardiac function in Lewis rats with EAM. Down-regulated costimulatory molecules in the myocardium and reduced inflammatory cytokine secretion might be responsible for the beneficial effects of ICOSIg in this model.

Adenoviridae ; genetics ; Animals ; Antigens, Differentiation, T-Lymphocyte ; genetics ; Autoimmune Diseases ; immunology ; pathology ; therapy ; Disease Models, Animal ; Gene Transfer Techniques ; Genetic Therapy ; Genetic Vectors ; Immunoglobulin Fc Fragments ; genetics ; Inducible T-Cell Co-Stimulator Protein ; Male ; Myocarditis ; immunology ; pathology ; therapy ; Rats ; Rats, Inbred Lew ; Recombinant Fusion Proteins ; genetics

Recent studies revealed that apoptotic cells are actively involved in immunosuppression and anti-inflammation. After being phagocytosed by macrophages, apoptotic cells can actively regulate cytokines secretion from lipopolysaccharide (LPS)-stimulated macrophages, in which the secretion of immunosuppressive cytokines such as interleukin-10 (IL-10) is increased while the pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNFa), interleukin-1beta (IL-1b) and leukin-8 (IL-8) are suppressed. In this paper, we first present evidence that phagocytosed apoptotic cells regulate cytokine secretion of LPS-stimulated macrophages, but also inhibit the activation of T lymphocytes stimulated by ConA. These data suggest that apoptotic cells can alter the biological behavior of macrophages which gain immunosuppressive property.
Animals ; Antigens, CD ; metabolism ; Antigens, Differentiation, T-Lymphocyte ; metabolism ; Apoptosis ; immunology ; Chemokine CXCL2 ; Chemokines ; biosynthesis ; genetics ; Concanavalin A ; pharmacology ; Cytokines ; biosynthesis ; Female ; Humans ; Immune Tolerance ; In Vitro Techniques ; Jurkat Cells ; Lectins, C-Type ; Lipopolysaccharides ; pharmacology ; Lymphocyte Activation ; drug effects ; Macrophages ; drug effects ; immunology ; Mice ; Mice, Inbred ICR ; Phagocytosis ; Receptors, Interleukin-2 ; metabolism ; Signal Transduction ; immunology ; T-Lymphocytes ; drug effects ; immunology ; Tumor Necrosis Factor-alpha ; biosynthesis ; genetics

The expression of inducible co-stimulator (ICOS) in peripheral blood T lymphocytes from the patients with systemic lupus erythematosus (SLE) and the role in the pathogenesis of SLE was investigated. By using two-color immunofluorescent staining and flow cytometric assay, the expression levels of ICOS in peripheal blood T lymphocytes from 33 patients with SLE and 16 healthy volunteers were detected. SLE diseases activity index (SLEDAI) of the patients with SLE was used to evaluate the disease activity. The correlation between the ICOS expression and SLEDAI was analyzed among the groups. The results showed that the expression levels of ICOS in T lymphocytes in active SLE group was markedly higher than those in the control and inactive SLE groups (both P< 0.01). There was no significant difference in the expression levels of ICOS between the inactive SLE and the control groups (P>0.05). In active SLE and inactive SLE groups, positive linear correlation was found between the levels of the ICOS expression in T lymphocytes and SLEDAI (r=0. 711, P=0.001; r=0.561, P=0.03). It was suggested that the expression of ICOS in peripheral blood T lymphocytes from the patients with active SLE was up-regulated and and ICOS might be related to the pathogenesis of SLE.
Antigens, Differentiation, T-Lymphocyte/*biosynthesis ; Antigens, Differentiation, T-Lymphocyte/genetics ; Lupus Erythematosus, Systemic/blood ; Lupus Erythematosus, Systemic/etiology ; Lupus Erythematosus, Systemic/*immunology ; T-Lymphocytes/*immunology