Cellular immunity is an important component of human immune system and plays a crucial role in the fight against tumor cell or invasive pathogens. Researches on cell-based immunotherapy have long been focused on eliciting tumor-specific CD8+ cytotoxic T lymphocytes (CTL) because of their potent killing activity and their ability to reject transplanted organs. However, the resulting treatments have been surprisingly poor at inducing complete tumor rejection, in both the experimental models and clinical trials. The CD4+ T cells has been studied mainly for their role as helpers for CD8+ CTL, even suggesting that the tumor-specific CD4 T regulatory cells could act as suppressors of antitumor responses. Recent studies indicated that CD4+T cells are not a pure cell lineage with single function, but a cell population with complex functions. Moreover CD4+ T cells may not only be helper cells, but also act as potent effector cells or partners with NK cells that can clear a wide variety of tumors. In a word, the antitumor potential of effector CD4+ T cells might have been underestimated. In this article, the classification and differentiation of CD4+ T cells, the function and secreted cytokines of CD4+ T cells, the CD4+ T cells and tumor immune, the tumor-immuno regulatory effects of CD4+ T cells, and clinical researches of CD4+ T cells are reviewed.
CD4-Positive T-Lymphocytes ; classification ; cytology ; immunology ; Cytokines ; metabolism ; Cytotoxicity, Immunologic ; Humans ; Immunity, Cellular

PURPOSE: This study was done to evaluate the effects of psychosocial interventions on cortisol and immune response in adult patients with cancer. METHODS: MEDLINE via PubMed, Cochrane Library CENTRAL, EMBASE, CINAHL and domestic electronic databases were searched. Twenty controlled trials (11 randomized and 9 non-randomized trials) met the inclusion criteria with a total of 862 participants. Methodological quality was assessed using the Cochrane's Risk of Bias for randomized studies and the Risk of Bias Assessment tool for non randomized studies. Data were analyzed using the RevMan 5.2.11 program of Cochrane library. RESULTS: Overall, study quality was moderate to high. The weighted average effect size across studies was -0.32 (95% CI [-0.56, -0.07], p=.010, I2=45%) for cortisol concentration, -0.62 (95%CI [-0.96,-0.29], p<.001, I2=0%) for T lymphocyte (CD3) and -0.45 (95%CI [-0.74, -0.16], p=.003, I2=0%) for Th lymphocyte (CD4) numbers. Psychosocial interventions were not effective for Tc lymphocyte (CD4), NK cell, monocyte, and cytokine response. CONCLUSION: Although these results provide only small evidence of successful immune modulation, they support the conclusion that psychosocial interventions can assist cancer patients in reducing emotional distress and improving immune response.
CD4-Positive T-Lymphocytes/cytology/immunology ; Cytokines/metabolism ; Databases, Factual ; Humans ; Hydrocortisone/*analysis ; Killer Cells, Natural/cytology/immunology ; Monocytes/cytology/immunology ; Neoplasms/metabolism/pathology/*therapy ; Psychotherapy ; T-Lymphocytes/cytology/*immunology

CD4+ T lymphocytes play a major role in regulation of adaptive immunity. Upon activation, naive T cells differentiate into different functional subsets. In addition to the classical Th1 and Th2 cells, several novel effector T cell subsets have been recently identified, including Th17 cells. There has been rapid progress in characterizing the development and function of Th17 cells. Here I summarize and discuss on the genetic controls of their differentiation and emerging evidence on their plasticity. This information may benefit understanding and treating immune diseases.
Animals ; CD4-Positive T-Lymphocytes/cytology/*immunology ; Cell Differentiation ; Cell Lineage ; Cytokines/*genetics ; Epigenesis, Genetic ; Gene Expression Regulation ; Humans ; Interleukin-17/immunology/metabolism ; T-Lymphocytes, Regulatory ; Th1 Cells/immunology ; Th17 Cells/*immunology ; Th2 Cells/immunology ; Transcription Factors/*genetics ; Transcription, Genetic

Blockade of signal 1 or 2 for T-cell activation by the use of anti-CD45RB and anti-CD154 monoclonal antibodies (mAb) (two-signal blockade) has been proven effective in preventing or delaying graft rejection. However, the mechanisms of its immunomodulatory effects are clearly unknown and the present studies were performed to determine how the two-signal blockade modulate allogeneic immune responses, especially T-cell mediated cellular immunity, in a murine skin allograft model. We now report on the profound inhibition of alloreactive T cells by two-signal blockade via CD4-dependent mechanisms. C57BL/6 mice of BALB/c skin allograft were treated with anti-CD45RB, anti-CD154, CTLA4-Ig, or their combinations. For depletion of CD4 or CD8 T cells, the recipients received CD4-depleting or CD8-depleting mAb. We confirmed that survival of skin allograft was markedly prolongated in the two-signal blockade-treated group. In depletion study, anti-CD45RB, anti-CD154 and CD4-depleting mAb-treated group showed acute rejection of skin allograft in contrast to CD8-depleting group treated with the two-signal blockade. In the group treated with the two-signal blockade, the proportions of CD4+CD45RB(low)and CD8+CTLA-4 regulatory T cells were increased while effector CD8+ T cells, including IFN-gamma-secreting and CD8+CD62L(low)T cells, were decreased when compared with non-treated group. In contrast, the CD4-depleted group treated with the two-signal blockade resulted in recovery from immunoregulatory effects of two-signal blockade. In addition, results of IL-4 and IL-10 production were also showed CD4-dependence. Therefore, the two-signal blockade is accompanied by CD4-dependent mechanisms in allogeneic skin transplantation.
Transplantation, Homologous ; T-Lymphocytes, Regulatory/cytology/immunology ; Skin Transplantation/*immunology ; Signal Transduction/drug effects/immunology ; Mice, Inbred C57BL ; Mice, Inbred BALB C ; Mice ; Male ; Lymphocyte Depletion ; Lymphocyte Activation/immunology ; Interleukin-4/biosynthesis ; Interleukin-10/biosynthesis ; Graft Rejection/*immunology/prevention & control ; Flow Cytometry ; Cytotoxicity, Immunologic/immunology ; CD8-Positive T-Lymphocytes/cytology/immunology/metabolism ; CD40 Ligand/*immunology ; CD4-Positive T-Lymphocytes/cytology/immunology/metabolism ; Antigens, CD45/*immunology ; Antigens, CD4/*immunology ; Antibodies, Monoclonal/administration & dosage/*pharmacology ; Antibodies, Blocking/administration & dosage/pharmacology ; Animals

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 biological characteristic of third-party-derived tolerogenic DC(tDC) and the influence of third-party-derived tDC on acute graft-versus-host-disease (aGVHD) following allogeneic bone marrow transplantation (allo-BMT) in mice.

METHODStDC from bone marrow cells of D1 mice was cultured with low doses of GM-CSF, IL-10 and TGF-β1D1. The phenotype, expression of cytokines and function associated molecules were identified with FACS and RT-PCR. Mixed lymphocyte reaction was applied to analyze the influence of third-party-derived tDC on allo-CD4(+)T cells proliferation in vitro. Different doses of D1-tDC were adoptive transferred in the aGVHD model in allogeneic BMT which B6 mice as donors and D2 mice as recipients. Survival time, clinical GVHD score and the levels of Th1/2 cytokines in serum were monitored after allo-BMT using the aGVHD model as control.

RESULTStDC expressed lower levels of MHC II and co-stimulatory molecules, such as CD80, CD86 and CD40, even when stimulated by LPS. The results by RT-PCR indicated that tDC expressed low levels of IL-12p40 and high levels of immunosuppressive molecules, such as IL-10, TGF-β, Fas Ligand, indoleamine 2, 3-dioxygenase (IDO) and arginase. In the allogeneic MLR, third-party tDC suppressed allo-CD4(+)T cells proliferation, which was relative to the dose of tDC. In the B6→D2 mouse model, all aGVHD mice died within 18 days. Remarkably, if 10(4) third-party tDC were transferred, 60% mice survived at least 60 days. When the doses of tDC were reduced to 10(3) cells, only 20% of mice survived day 60, and when increased tDC to 10(5), all of the mice died within day 37 after allo-BMT. The cytokine levels in serum indicated that 10(4) tDC-treated mice secreted in vivo high level of IL-10 21d after BMT (P < 0.05), the levels of IL-10 in 10(3), 10(4) and 10(5) tDC-treated mice were (114.23 ± 7.78), (646.18 ± 212.02), (121.97 ± 10.47) ng/L, respectively.

CONCLUSIONThird-party tDC could suppress allo-CD4(+)T cells proliferation in vitro and prevent aGVHD in allogeneic BMT mode, which may be mediated by modulating tolerogenic cytokines secretion, such as IL-10. And this effect was associated with the dose of tDC. Adoptive therapy by transfusing third-party tDC cultured with low doses of GM-CSF, IL-10 and TGF-β1 could significantly prolong the survival of recipients and prevent aGVHD in allogeneic BMT.

Animals ; Bone Marrow Transplantation ; adverse effects ; CD4-Positive T-Lymphocytes ; cytology ; Cell Proliferation ; Dendritic Cells ; cytology ; immunology ; metabolism ; Graft vs Host Disease ; prevention & control ; Interleukin-10 ; immunology ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Transforming Growth Factor beta1 ; immunology ; Transplantation, Homologous

T cell anergy has been successfully induced under different conditions in cloned CD4(+) T cells, but induction of T cell anergy in vivo has been difficult and controversial. Due to the low frequency of naturally occurring T cell population with specificity to a defined antigen, it is very difficult to study anergy of naïve T cells without prior in vivo priming which complicates the interpretation of experimental data. To solve this problem, we adopted the HNT-TCR transgenic mice which have homogeneous antigen specific CD4(+) T cell population. In this study, we generated an influenza virus hemagglutinin (HA) peptide-specific CD4(+) T cell clone from the HNT-TCR transgenic mice and induced anergy using APCs which were treated with the crosslinker, ECDI (1-ethyl-3-3(3-dimethylaminopropyl) carbodiimide). The proliferative response of the cloned or freshly purified naïve CD4(+) transgenic T cells after treatment with ECDI-treated APCs and the HA peptide antigen was monitored as the index of anergy induction. The results showed that anergy was successfully induced in the cloned HNT-TCR transgenic CD4(+) T cells. It was determined that the induced anergy was antigen- and MHC-specific. By contrast, anergy was not observed in freshly purified naïve CD4(+) transgenic T cells under the same conditions. The results suggest that naïve CD4(+) T cells may have different anergy inducing requirements, or that cloned CD4(+) T cells may have certain priming or in vitro cloning artifact which makes them more susceptible to anergy induction. We propose that induction of T cell anergy may depend on the T cell growth, activation and differentiation state or cloning conditions. The results from the present study may have important implications for the study of the mechanism(s) underlying T cell anergy induction in vivo and for applications of immune tolerance based therapy.
Animals ; Antigen-Presenting Cells ; immunology ; metabolism ; Antigens, CD ; genetics ; immunology ; metabolism ; CD4 Antigens ; immunology ; CD4-Positive T-Lymphocytes ; cytology ; immunology ; Clonal Anergy ; genetics ; immunology ; Clone Cells ; immunology ; Epitopes, T-Lymphocyte ; biosynthesis ; Immune Tolerance ; genetics ; Major Histocompatibility Complex ; immunology ; Mice ; Mice, Transgenic ; Receptors, Antigen, T-Cell ; physiology

OBJECTIVETo study the relationship between the change of regulatory T cell number in CD4+ T subset and the growth of tumor in H22 hepatocellular carcinoma-bearing mice.

METHODSTumor-bearing mice were established by subcutaneous inoculation of H22 hepatocelluler carcinoma cells. Flow cytometry was used to detect the expression of CD4 and CD25 molecules of the T cells which came from the tumor-bearing mice. The Foxp3 gene expression was detected by RT-PCR and flow cytometry. CD4+ CD25+ T cells and CD4+ CD25- T cells were separated and purified by immuno-magnetic beads. The proliferation and suppressive function of the CD4+ CD25+ T cells coming from tumor-bearing mice was measured by [3H]-thymidines incorporation experiment in vitro, and then effect of CD4+ CD25+ T cells originated from hepatocellular carcinoma-bearing mice on tumor growth was observed in vivo.

RESULTS(1) Compared with mice of the control group, the percentage of CD4+ CD25+ T cells of CD4+ T cells in tumor-bearing mice is not only higher in draining lymph nodes (18.80% < or = 0.06%) vs. (9.50% +/- 0.03%), (P < 0.01), but also higher in non-draining lymph nodes (LN) and spleen (SP), LN: (16.28% +/- 0.02%) vs. (9.50% +/- 0.03%), P < 0.01; SP: (17.28% +/- 0.06%) vs. (11.08% +/- 0.04%), (P < 0.05). The expression of regulatory T cell specific marker Foxp3 gene was also increased. In the same tumor-bearing mice, the number of CD4+ CD25+ T cells in draining lymph node was relatively higher than the contralateral nondraining lymph node, but the difference was statistically not significant (18.8% +/- 0.06%) vs. (16.28% +/- 0.02%), (P > 0.05). (2) The CD4+ CD25+ T cells purified from tumor-bearing mice--like naturally occurring regulatory T cells--were anergic to anti-CD3 monoclonal antibody stimulation in vitro, but it could suppress CD4+ CD25- T cells proliferation. (3) The percentage of CD4+ CD25+ T cells was positively related to tumor size. It could also suppress the anti-tumor effect of CD4+ CD25- T cells in vivo. Conclusion The growth of hepatocellular carcinoma in mice can boost the amount of regulatory T cells. The amount of regulatory T cells is positively related to tumor size, indicating that attack on regulatory T cells could be used as one of modalities in cancer treatment in the future.

Animals ; CD4 Antigens ; immunology ; CD4-Positive T-Lymphocytes ; cytology ; immunology ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; Female ; Flow Cytometry ; Forkhead Transcription Factors ; genetics ; metabolism ; Gene Expression Regulation, Neoplastic ; Interleukin-2 Receptor alpha Subunit ; immunology ; Liver Neoplasms ; immunology ; metabolism ; pathology ; Liver Neoplasms, Experimental ; immunology ; metabolism ; pathology ; Lymph Nodes ; immunology ; metabolism ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasm Transplantation ; Reverse Transcriptase Polymerase Chain Reaction ; Spleen ; immunology ; metabolism ; T-Lymphocytes, Regulatory ; cytology ; immunology ; metabolism

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 investigate the effect of tumor necrosis factor-α-induced protein 8 like-2 (TIPE2) on apoptosis of CD4T lymphocytes in a murine model of severe burn injury.

METHODSA total of 140 male mice were randomly allocated into 6 groups. Small RNA interference technique was used to construct a siTIPE2-overexpressing lentivirus, and severe burn injury models were established in the mice. CD4T cells were purified from spleen of the mice, and the expressions of TIPE2, Smad2/Smad3, P-Smad2/P-Smad3 and Bcl-2/Bimprotein in CD4Tregs were detected. The changes in mitochondrial membrane potential and cytochrome C in CD4T cells were detected, and the activities of caspase-3, caspase-8, and caspase-9 were analyzed.

RESULTSDown-regulation of TIPE2 promoted the apoptosis of CD4T lymphocytes in siTIPE2-burn group, in which the protein expressions of P-smad2/P-Smad3 decreased, Bcl-2 expression increased and Bim expression decreased significantly as compared with the other groups (P<0.01 or 0.05). The mitochondrial membrane potential and cytochrome C expression in CD4T cells were down-regulated in siTIPE2-burn group (P<0.05) with a lowered caspase-3 activity compared with TIPE2-burn group (P<0.01) and decreased caspase-8 and caspase-9 compared with the other groups (P<0.05). The apoptosis rate was the highest in TIPE2-burn group, whose Smad2/Smad3 was higher than that in the sham group (P<0.05) and the expression of P-smad2/P-Smad3 significantly increased compared with the other groups (P<0.05). In TIPE2-burn group, the mitochondrial membrane potential in CD4T cells was decreased (P<0.01), the expression of cytochrome C increased markedly (P<0.01), and the activities of caspase-3, caspase-8, and caspase-9 were all obviously higher than those in the other groups (P<0.05).

CONCLUSIONAs an important immunoregulatory molecule, TIPE2 can promote the apoptosis of CD4T lymphocyte in mice with sever burn injury.

Animals ; Apoptosis ; Burns ; immunology ; CD4-Positive T-Lymphocytes ; cytology ; Caspase 3 ; metabolism ; Caspase 8 ; metabolism ; Caspase 9 ; metabolism ; Down-Regulation ; Intracellular Signaling Peptides and Proteins ; metabolism ; Male ; Mice ; Smad2 Protein ; metabolism ; Smad3 Protein ; metabolism ; Spleen