The function of immune system degenerates in an aging-dependent manner and this results in immunosenescence. Human immune system includes two parts: genetic/innate immunity and adaptive immunity. The former is involved in monocytes, nature killer cells, and dendritic cells, the later is involved in acquired B and T lymphocytes. During the aging of immunity system, the both parts of immunity are damaged to some degree. Generally, innate immunity seems well-retained and the acquired immunity is degenerative seriously with aging. Immunocyte senescence is closely related to the elderly decreased ability to control infectious disease, cancer and to their generally poor response to vaccination. This review summarized the research progress on immunosenescence characteristics in aged phase.
Age Factors ; Aging ; immunology ; Antibody Formation ; immunology ; Cellular Senescence ; Humans ; Immunity, Cellular ; immunology ; Lymphocyte Activation

We studied host immune parameters which might be related to the activity and the pathogenetic mechanism of chronic active hepatitis. The subjects consisted of 45 cases with hepatitis B virus surface antigen (HBsAg)-positive chronic active hepatitis (CAH), 44 HBsAg-negative CAH, 22 with inactive chronic hepatitis, and 45 cases of normal persons, hepatitis B virus (HBV) carriers, or the patients with acute myocardial infarction. The in vitro assay for the in vivo activated lymphocytes was performed by measuring spontaneous thymidine uptake (SLT) of lymphocytes isolated from peripheral blood. SLT was significantly (p less than 0.001) elevated in cases with HBsAg-positive (1227 +/- 806 cpm) and-negative CAH (1017 +/- 559 cpm) compared to the patients with inactive chronic hepatitis (347 +/- 79 cpm) and to the control group (320 +/- 106 cpm). SLT values observed in 7 cases with active disease (group I and II), in which remission and relapsing phase could be assessable, were elevated from 648 +/- 121 cpm in remission phase to 1548 +/- 606 cpm one to two weeks before the appearance of biochemical evidence (SGPT) of relapse. This pattern of SLT elevation, however, was not observed in patients with inactive hepatitis. Neither the abnormal distribution of T-celi subsets nor the presence of conventional HBV markers were related to the elevated SLT value. Our findings may therefore indicate that SLT might be useful in assessment of the disease activity in patients with CAH.
Adult ; Alanine Transaminase/blood ; Female ; Hepatitis, Chronic/*immunology ; Humans ; Lymphocyte Activation ; Lymphocyte Culture Test, Mixed ; Male ; Middle Aged ; T-Lymphocyte Subsets/immunology

This study was aimed to explore the level of NK cell activity in the patients with secondary hemophagocytic syndrome (HPS) and its significance for early diagnosis of this disease. 16 suspected HPS patients and 25 healthy subjects were enrolled in this study. The activity of NK cells in peripheral blood was detected by a released LDH assay. The activity level of NK cells in peripheral blood from patients who were finally diagnosed as HPS was compared with healthy subjects. The results showed that 8 out of 16 suspected HPS patients were finally diagnosed as secondary HPS. The activity of NK cells in peripheral blood of these 8 patients was obviously lower than that in healthy subjects with statistical significance (p<0.001), and showed abnormal in the early stage of this disease. It is concluded that the detection of NK cell activity may play an important role in earlier diagnosis of secondary hemophagocytic syndrome.
Case-Control Studies ; Early Diagnosis ; Humans ; Killer Cells, Natural ; immunology ; Lymphocyte Activation ; immunology ; Lymphohistiocytosis, Hemophagocytic ; diagnosis ; immunology

This study was purposed to explore the immunoregulatory effects of human bone marrow mesenchymal stem cells (MSCs) on active T lymphocytes in vitro and the new strategy to prevent graft-versus-host disease (GVHD) in allogeneic hematopoietic stem cell transplantation (allo-HSCT). Mononuclear cells from human peripheral blood cells were isolated and cultured in the presence of phytohemagglutinin (PHA) (final concentration was 10 microg/ml) for different times. The ability of T lymphocyte proliferation and activation was measured by (3)H-Thyramine incorporation. The expressions of CD3(+)CD4(+), CD3(+)CD8(+), CD4(+)CD25(+) and CD4(+)CD152(+) on T cells were detected by FCM after coculture for 72 hours. Experiment was divided into 4 groups: A group as control (no added MSCs), B group (actived T cells + 2 x 10(4) MSCs), C group (actived T cells + 4 x 10(4) MSCs), D group (actived T cells + 8 x 10(4) MSCs). The results showed that the ability of T lymphocyte proliferation in the same PHA concentration increased with prolonging of time. ability of T lymphocyte proliferation was strongest when culturing for 48 hours (p < 0.01); the expressions of CD44, CD105, CD29 and FIK1 of MSCs were positive, expressions of CD33, CD34, CD45 and HLA-DR were negative. MSCs inhibited T lymphocyte proliferation and the inhibitory effect depended on the amount of MSCs. CD3(+)CD8(+), CD4(+)CD25(+) and CD4(+)CD152(+) T cells cocultured with MSCs increased obviously and CD3(+)CD4(+) expression significantly decreased, as compared with control group (p < 0.01). It is concluded that the MSCs inhibit T lymphocyte proliferation induced by mitogen (PHA), and perform their immunosuppressive function by up-regulation of CD3(+)CD8(+), CD4(+)CD25(+) and CD4(+)CD152(+) expressions and down-regulation of CD3(+)CD4(+) expression.
Bone Marrow Cells ; cytology ; Cell Separation ; Cells, Cultured ; Humans ; Lymphocyte Activation ; immunology ; Mesenchymal Stromal Cells ; cytology ; immunology ; T-Lymphocytes ; immunology

The aim of this study was to explore the regulatory function of interleukin-6(IL-6) on human Th17 cells. Human peripheral blood CD4(+) T cells were purified from healthy donors by anti-CD4 monoclonal antibody (mAb) conjugated microbeads. The experiment was divided into 2 groups. Test group in which CD4(+) T cells (1 × 10(6)/ml) were stimulated by human recombined IL-6 (20 ng/ml) for 4 days; control group in which CD4(+) T cells did not stimulated by IL-6. The concentrations of IL-17 protein in the supernatants were assayed by enzyme-linked immunosorbent assay (ELISA), and quantity of Th17 cells were detected by flow cytometry. The results showed that as compared to control group, IL-17 protein level in the supernatants of CD4(+) T cells significantly increased in IL-6 stimulated group: (337.05 ± 189.09 pg/ml; vs 15.07 ± 12.70 pg/ml) (p < 0.05). Furthermore, the percentage of Th17 cells in cultures of CD4(+) T cells stimulated by IL-6 was significantly higher than that in control group (4.05% ± 0.30% vs. 2.81% ± 0.44%)(p < 0.01). It is concluded that IL-6 promotes the expansion of Th17 cells in vitro.
CD4-Positive T-Lymphocytes ; cytology ; immunology ; Cells, Cultured ; Humans ; Interleukin-6 ; pharmacology ; Lymphocyte Activation ; immunology ; Th17 Cells ; drug effects ; immunology

OBJECTIVETo establish a method for isolating exosomes from dendritic cells (DC), and to analyse its biological characteristics and function in antitumor immunity.

METHODSImmature DCs (im-DC) from human peripheral blood mononuclear cells were loaded with the antigen of K562 tumor cells, then exosomes were secreted from imDC and lipopolysaccharide (LPS) induced mature DC (mDC). The exosomes from imDC and mDC were isolated separately by ultracentrifugation and ultrafiltration. The exosomes diameter was determined, their profile was observed by electron microscope, and the surface molecules were detected by Western blot. To analyse the effect of exosomes on antitumor immunity, the proliferation, IFN-gamma expression, CD69 up-regulation and cytotoxicity of antigen-specific T cells were measured.

RESULTSExosomes were small flattened sphere vesicles with an average diameter of 72.3 nm and expressed CD80, CD86, HLA-DR, FasL, CD54 and MFG-E8 molecules. As compared to immature exosomes, exosomes from mDC were proved to express more CD80 and less MFG-E8, to be more potent for inducing antigen-specific T cells proliferation and immunity respond in vitro: at its optimum concentration, the absorption value of T cell proliferation test was 0.50 +/- 0.01, CD69 was up-regulated and (13.4 +/- 5.8)% of T cells was in proliferating, (22.8 +/-2.4)% of T cells expressed IFN-gamma, and (21.3 +/-8.6)% of tumor cells were killed.

CONCLUSIONA simple and quick method to isolate and analyse exosomes is established. The exosomes can induce antitumor immunity respond.

Cells, Cultured ; Dendritic Cells ; immunology ; secretion ; Exosomes ; immunology ; Humans ; Lymphocyte Activation ; drug effects ; T-Lymphocytes ; drug effects ; immunology

AIMTo investigate intermittent hypoxia effects on splenocyte mitogen-induced proliferation.

METHODSRats were exposured to intermittent hypoxia in a hypobaric chamber 4 h/d for 1 d, 2 d, 5 d and 15 d.

RESULTS5 km (10.8% O2) hypoxia for 1 d significantly inhibited ConA-induced splenocytes proliferation by--74.57% +/- 7.33% (P < 0.05). Hypoxia (5 km) for 2 d, 5 d and 15 d did not markedly affect splenocyte proliferation (97.03 +/- 7.18%, 104.5% +/- 8.38%, 99.55% +/- 3.8% respectively). Hypoxia 2 km (16.0% O2) for 1 d, 2 d, 5 d and 15 d had no influence on splenocytes proliferation (93.19% +/- 11.88%, 96.43% +/- 7.9%, 99.03% +/- 10.97%, 100.54% +/- 9.54% respectively). We also demonstrated that acute hypoxia exposure (5 km) 4 h significantly suppressed DNA contents of rat splenocytes by 76.22% +/- 7.06% (P < 0.05). The suppressed DNA synthesis were returned to control level after the hypoxia for 5 d and 15 d.

CONCLUSIONThese results suggest that the acute hypoxia (5 km, 4 h) induces a transient suppression on splenic lymphocyte proliferation, and the intermittent hypoxia may induce an adaptation response of the splenocytes proliferation.

Animals ; Cell Proliferation ; Hypoxia ; immunology ; Lymphocyte Activation ; Lymphocytes ; cytology ; immunology ; Male ; Rats ; Rats, Sprague-Dawley ; Spleen ; immunology

In allogeneic transplantation, including the B6 anti-BALB.B settings, H60 and H4 are two representative dominant minor histocompatibility antigens that induce strong CD8 T-cell responses. With different distribution patterns, H60 expression is restricted to hematopoietic cells, whereas H4 is ubiquitously expressed. H60-specific CD8 T-cell response has been known to be dominant in most cases of B6 anti-BALB.B allo-responses, except in the case of skin transplantation. To understand the mechanism underlying the subdominance of H60 during allogeneic skin transplantation, we investigated the dynamics of the H60-specific CD8 T cells in B6 mice transplanted with allogeneic BALB.B tail skin. Unexpectedly, longitudinal bioluminescence imaging and flow cytometric analyses revealed that H60-specific CD8 T cells were not always subdominant to H4-specific cells but instead showed a brief dominance before the H4 response became predominant. H60-specific CD8 T cells could expand in the draining lymph node and migrate to the BALB.B allografts, indicating their active participation in the anti-BALB.B allo-response. Enhancing the frequencies of H60-reactive CD8 T cells prior to skin transplantation reversed the immune hierarchy between H60 and H4. Additionally, H60 became predominant when antigen presentation was limited to the direct pathway. However, when antigen presentation was restricted to the indirect pathway, the expansion of H60-specific CD8 T cells was limited, whereas H4-specific CD8 T cells expanded significantly, suggesting that the temporary immunodominance and eventual subdominance of H60 could be due to their reliance on the direct antigen presentation pathway. These results enhance our understanding of the immunodominance phenomenon following allogeneic tissue transplantation.
Animals ; Antigen Presentation ; Antigen-Presenting Cells/immunology/metabolism ; CD8-Positive T-Lymphocytes/*immunology ; Epitopes, T-Lymphocyte/*immunology ; Female ; Graft Rejection/*immunology ; Interferon-gamma ; Lymphocyte Activation/immunology ; Lymphocyte Count ; Mice ; Minor Histocompatibility Antigens/*immunology/metabolism ; *Skin Transplantation ; Transplantation, Homologous

OBJECTIVETo test the antitumor effect of a human triple-negative breast cancer cell-dendritic cell (DC) fusion vaccine.

METHODSDCs were isolated from fresh peripheral blood of healthy donors. The fusion vaccine was prepared by fusing the DCs and MDA-MB-231 cells via electrofusion. The morphology of the vaccine was identified under inverted fluorescence microscope and the phenotypes were analyzed with flow cytometry. The production of interleukin-12 (IL-12) and interferon-γ (IFN-γ) by the fusion cells was assessed using ELISA. A CCK-8 kit was used to examine the effect of the vaccine in stimulating the proliferation and cytotoxicity of autologous T lymphocytes.

RESULTSThe DCs isolated from peripheral blood mononuclear cells highly expressed CD83, CD86, CD11c and HLA-DR on the cell surface. The fusion cells were irregular in shape and coexpressed the phenotypes of DCs and MDA-MB-231 cells. The fusion cells possessed a strong ability to stimulate the proliferation of T lymphocytes in vitro. Compared with the control group, the fusion vaccine showed a stronger antitumor effect against the breast cancer cells.

CONCLUSIONThe triple-negative breast cancer-DC fusion vaccine prepared by electrofusion can stimulate the proliferation of T lymphocytes and induces strong cytotoxicity of the T cells against breast cancer cells.

Breast Neoplasms ; immunology ; Cancer Vaccines ; immunology ; Cell Fusion ; Cell Line, Tumor ; Dendritic Cells ; immunology ; Female ; Humans ; Interferon-gamma ; immunology ; Interleukin-12 ; immunology ; Lymphocyte Activation ; T-Lymphocytes, Cytotoxic ; immunology

This study was aimed to establish the reference values of blood lymphocyte immunophenotype in healthy adult between Ugyur and Han nationalities in Xinjiang and to compare the difference between these two nationalities in respect to nationality and gender, anticoagulated peripheral blood samples of 75 Ugyur people and 104 Han people were stained with monoclonal antibodies; the lymphocytes were analyzed by flow cytometry for the expression of lymphocyte-population bearing surface markers, the data were analyzed by SPSS 11.0. The results showed that the reference ranges of blood lymphocyte subsets in Uygur and Han adults were as follows: total T cells amounted to 67.85 +/- 8.97% and 69.98 +/- 10.14% respectively; helper T cell to 36.86 +/- 5.74% and 40.07 +/- 6.10% respectively; inhibitor T cell to 26.67 +/- 6.15% and 27.16 +/- 6.29% respectively; CD4/CD8 ratio to 1.46 +/- 0.47 and 1.56 +/- 0.47 respectively; NK cell to 16.91 +/- 9.89% and 12.81 +/- 7.34% respectively; B cell to 10.09 +/- 3.33% and 11.78 +/- 3.81% respectively; CD3(+)/HLA-DR(+) to 10.05 +/- 2.95% and 11.27 +/- 4.98% respectively; CD25(+) cell to 1.76 +/- 5.26% and 4.10 +/- 4.30% respectively. The differences of those two nationalities were mainly in total T cells, NK cell, B cell and CD25(+) cell. Furthermore there were also some differences between male and female. There might exist differences in helper T cells, CD4/CD8 ratio between Ugyur male and female, while this difference in Han lied in inhibitor cell and NK cell. Compared to those of two nationalities, the helper T cell percentage and CD4/CD8 ratio of Uygur male were lower than those in Han male. And in female, Uygur people had higher percent of NK cell (P < 0.01), but lower CD25(+) cell than those in Han's (P < 0.01). In conclusion, the nationalities and gender could influence the reference value of lymphocyte immunophenotype, the reference values of blood lymphocyte immunophenotype in the normal healthy adults of Ugyur and Han nationalities in Xinjiang were defined, and the differences between these two nationalities in respect to nationality and gender were elucidated.
Adult ; China ; ethnology ; Female ; Flow Cytometry ; Humans ; Immunophenotyping ; methods ; Killer Cells, Natural ; immunology ; Lymphocyte Activation ; immunology ; Lymphocyte Subsets ; immunology ; Male ; Middle Aged ; Reference Values ; T-Lymphocyte Subsets ; immunology ; T-Lymphocytes ; immunology