BACKGROUNDTriggering receptor expressed on myeloid cell-1 (TREM-1) may play a vital role in mammalian target of rapamycin (mTOR) modulation of CD8+ T-cell differentiation through the transcription factors T-box expressed in T-cells and eomesodermin during the immune response to invasive pulmonary aspergillosis (IPA). This study aimed to investigate whether the mTOR signaling pathway modulates the proliferation and differentiation of CD8+ T-cells during the immune response to IPA and the role TREM-1 plays in this process.

METHODSCyclophosphamide (CTX) was injected intraperitoneally, and Aspergillus fumigatus spore suspension was inoculated intranasally to establish the immunosuppressed IPA mouse model. After inoculation, rapamycin (2 mg.kg-1.d-1) or interleukin (IL)-12 (5 μg/kg every other day) was given for 7 days. The number of CD8+ effector memory T-cells (Tem), expression of interferon (IFN)-γ, mTOR, and ribosomal protein S6 kinase (S6K), and the levels of IL-6, IL-10, galactomannan (GM), and soluble TREM-1 (sTREM-1) were measured.

RESULTSViable A. fumigatus was cultured from the lung tissue of the inoculated mice. Histological examination indicated greater inflammation, hemorrhage, and lung tissue injury in both IPA and CTX + IPA mice groups. The expression of mTOR and S6K was significantly increased in the CTX + IPA + IL-12 group compared with the control, IPA (P = 0.01; P= 0.001), and CTX + IPA (P = 0.034; P= 0.032) groups, but significantly decreased in the CTX + IPA + RAPA group (P < 0.001). Compared with the CTX + IPA group, the proportion of Tem, expression of IFN-γ, and the level of sTREM-1 were significantly higher after IL-12 treatment (P = 0.024, P= 0.032, and P= 0.017, respectively), and the opposite results were observed when the mTOR pathway was blocked by rapamycin (P < 0.001). Compared with the CTX + IPA and CTX + IPA + RAPA groups, IL-12 treatment increased IL-6 and downregulated IL-10 as well as GM, which strengthened the immune response to the IPA infection.

CONCLUSIONSmTOR modulates CD8+ T-cell differentiation during the immune response to IPA. TREM-1 may play a vital role in signal transduction between mTOR and the downstream immune response.

Animals ; CD8-Positive T-Lymphocytes ; cytology ; metabolism ; Cell Differentiation ; genetics ; physiology ; Female ; Interferon-gamma ; metabolism ; Invasive Pulmonary Aspergillosis ; metabolism ; Lymphocyte Activation ; genetics ; physiology ; Mice ; Mice, Inbred BALB C ; Myeloid Cells ; cytology ; metabolism ; Ribosomal Protein S6 Kinases ; metabolism ; TOR Serine-Threonine Kinases ; genetics ; metabolism ; Tissue Culture Techniques

BACKGROUNDAspergillosis infection is common in the patients with insufficient immunity. The role of mammalian target of rapamycin (mTOR), T-box expressed in T-cells (T-bet), and eomesodermin (EOMES) in mediating T lymphocytes differentiation in response to Aspergillus fumigatus infection in immunocompromised rats was investigated in this study.

METHODSInvasive pulmonary aspergillosis (IPA) of immunosuppressive twenty male rats were established and sacrificed at 24 h (n = 5), 48 h (n = 5), 72 h (n = 5), and 96 h (n = 5) after A. fumigatus infection. In addition, control (n = 5), cyclophosphamide (CTX) (n = 5), and aspergillosis (n = 5) group were also established the tissues and pathology of lung tissue was examined by hematoxylin and eosin staining. CD8+ T-cells was sorted by flow cytometry. Serum mTOR, S6K, T-bet, and EOMES were quantified by enzyme-linked immunosorbent assay.

RESULTSHistology of lung tissue indicated severe lung tissue injury including infiltration of inflammatory cells, alveolar wall damage or degradation, blood congestion, and hemorrhage in the CTX, IPA, and CTX + IPA rats. Hyphae were seen in the IPA, and CTX + IPA groups. The proportion of CD8+ T-cells was significantly increased in the animals of CTX + IPA. Memory CD8+ T-cells was significantly increased in early stage (24 h and 48 h, P < 0.001), but decreased in the late phase of fungal infection (72 h and 96 h) in the animals of CTX + IPA. In addition, at early stage of fungal infection (24 h and 48 h), serum mTOR (P < 0.001), S6K (P < 0.001), and T-bet (P < 0.05) was significantly higher, while EOMES was significantly lower (P < 0.001), in CTX + IPA group than that in control, CTX alone or IPA alone group. Conversely, serum mTOR, S6K, T-bet, and EOMES showed opposite changed in the late stage (72 h and 96 h). Pearson's correlation analysis indicated that mTOR and S6K were significantly correlated with T-bet (r = 0.901 and 0.91, respectively, P < 0.001), but negatively and significantly correlated with EOMES (r = -0.758 and -0.751, respectively, P < 0.001).

CONCLUSIONSmTOR may regulate transcription factors of EOMES and T-bet, and by which mechanism, it may modulate lymphocytes differentiation in animals with immune suppression and fungal infection.

Animals ; CD8-Positive T-Lymphocytes ; cytology ; metabolism ; Cell Differentiation ; genetics ; physiology ; Invasive Pulmonary Aspergillosis ; metabolism ; pathology ; Lung ; metabolism ; pathology ; Lymphocytes ; cytology ; immunology ; Male ; Rats ; Rats, Wistar ; T-Box Domain Proteins ; genetics ; metabolism ; TOR Serine-Threonine Kinases ; genetics ; metabolism ; Tissue Culture Techniques

OBJECTIVETo investigate the effects of iron overload on apoptosis and function of splenic CD8+ T cells in mice.

METHODSForty C57BL/6 mice were randomly divided into control groups, Iron overload (IO), IO+NAC and IO+DFX groups. The iron overload model was established by intraperitoneal injection of iron dextran, and saline was injected as the control. The levels of intracellular reactive oxygen species (ROS) and labile iron pool (LIP) were analyzed by measuring the mean fluorescence intensity (MFI) of 2-7 dichlorofluorescein (DCF) or calcein. The ratio of CD8+ T cells and the levels of IFN-γ, TNF-α, Granzyme-B, and perforin in CD8+ T cells were detected by flow cytometry. The CD8+ T cell apoptosis was determined by flow cytometry with Annexin V/PI double staining. Real-time PCR was used to detect the expression of IFN-γ, TNF-α, Granzyme-B, perforin, BCL-2, and bax at mRNA level in CD8+ T cells.

RESULTSIron overload was found by spleen iron staining and flow cytometry. The level of intracellular ROS in iron overload (IO) groups was higher than that of the control groups (P<0.01). The percentage of CD8+ T cells in spleen from mice with IO was lower than that in control groups (P<0.05). The expression of IFN-γ and Granzyme-B in CD8+ T cells in IO group were lower than that in control group, the expression of IFN-γ and Granzyme-B at mRNA level in CD8+ T cells was lower than that of control group (P<0.05). CD8+ T cell apoptosis in iron overload group was significantly higher than that in control groups (P<0.01); the expression of BCL-2 at mRNA level was lower than that in control group, but the expression of BAX at mRNA level was higher than that in control group (P<0.05). These effects could be reversed after treating iron-overloaded mice with DFX or NAC.

CONCLUSIONIron overload can inhibit the ratio of CD8+ T cells of splenic cells in mice, decrease the expression of IFN-γ, Granzyme-B, increase the apoptosis of CD3+ CD8+/CD8-. These effects may be regulated through increasing the intracellular ROS level, and can be partially reversed after treating iron-overloaded mice with DFX or NAC.

Animals ; Apoptosis ; CD8-Positive T-Lymphocytes ; cytology ; pathology ; Granzymes ; metabolism ; Interferon-gamma ; metabolism ; Iron ; metabolism ; Iron Overload ; physiopathology ; Mice ; Mice, Inbred C57BL ; Perforin ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Random Allocation ; Reactive Oxygen Species ; metabolism ; Spleen ; cytology ; Tumor Necrosis Factor-alpha ; metabolism ; bcl-2-Associated X Protein ; metabolism

Heat-shock protein (Hsp) 70 potentiates specific immune responses to some antigenic peptides fused to it. Here, the prokaryotic plasmids harboring the envelope glycoprotein E0 gene of classical swine fever virus (CSFV) and/or the Hsp70 gene of Haemophilus parasuis were constructed and expressed in Escherichia coli Rosseta 2(R2). The fusion proteins were then purified. Groups of Balb/c mice were immunized with these fusion proteins, respectively, and sera collected 7 days after the third immunization. Immune effects were determined via an enzyme-linked immunosorbent assay and flow cytometric analyses. E0-Hsp70 fusion protein and E0+Hsp70 mixture significantly improved the titer of E-specific antibody, levels of CD4+ and CD8+ T cells, and release of interferon-γ. These findings suggested that Hsp70 can significantly enhance the immune effects of the envelope glycoprotein E0 of CSFV, thereby laying the foundation of further application in pigs.
Animals ; Antibodies, Viral ; blood ; CD4-Positive T-Lymphocytes ; cytology ; immunology ; CD8-Positive T-Lymphocytes ; cytology ; immunology ; Cell Proliferation ; Classical swine fever virus ; genetics ; Female ; HSP70 Heat-Shock Proteins ; genetics ; immunology ; Haemophilus parasuis ; genetics ; Immunization ; Interferon-gamma ; metabolism ; Mice ; Mice, Inbred BALB C ; Plasmids ; genetics ; Recombinant Fusion Proteins ; genetics ; immunology ; Viral Envelope Proteins ; genetics

We evaluated the effectiveness of rhamnogalacturonan II (RG-II)-stimulated bone marrow-derived dendritic cells (BMDCs) vaccination on the induction of antitumor immunity in a mouse lymphoma model using EG7-lymphoma cells expressing ovalbumin (OVA). BMDCs treated with RG-II had an activated phenotype. RG-II induced interleukin (IL)-12, IL-1beta, tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) production during dendritic cell (DC) maturation. BMDCs stimulated with RG-II facilitate the proliferation of CD8+ T cells. Using BMDCs from the mice deficient in Toll-like receptors (TLRs), we revealed that RG-II activity is dependent on TLR4. RG-II showed a preventive effect of immunization with OVA-pulsed BMDCs against EG7 lymphoma. These results suggested that RG-II expedites the DC-based immune response through the TLR4 signaling pathway.
Acute-Phase Proteins/metabolism ; Adaptor Proteins, Vesicular Transport/metabolism ; Animals ; Antigens, CD14/metabolism ; Bone Marrow Cells/cytology/drug effects ; CD8-Positive T-Lymphocytes/*immunology ; Carrier Proteins/metabolism ; Cell Differentiation/drug effects ; Cell Nucleus/drug effects/metabolism ; Cell Proliferation/drug effects ; Cytokines/biosynthesis ; Dendritic Cells/cytology/drug effects/enzymology/*immunology ; Enzyme Activation/drug effects ; Lymphocyte Activation/*drug effects ; Membrane Glycoproteins/metabolism ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Mitogen-Activated Protein Kinases/metabolism ; Myeloid Differentiation Factor 88/metabolism ; NF-kappa B/metabolism ; Neoplasms/immunology/*pathology ; Pectins/*pharmacology ; Phenotype ; Protein Transport/drug effects ; Receptors, Chemokine/metabolism ; Signal Transduction/drug effects ; T-Lymphocytes, Cytotoxic/cytology/drug effects ; Toll-Like Receptor 4/*agonists/metabolism

In this study, we showed the direct interaction between Mycobacterium avium subsp. paratuberculosis fibronectin attachment protein (FAP) and toll-like receptor4 (TLR4) via co-localization and binding by using confocal microscopy and co-immunoprecipitation assays. FAP triggered the expression of pro- and anti-inflammatory cytokines in a TLR4-dependent manner. In addition, FAP-induced cytokine expression in bone marrow-derived dendritic cells (BMDCs) was modulated in part by glycogen synthase kinase-3 (GSK-3). FAP-induced expression of CD80, CD86, major histocompatibility complex (MHC) class I, and MHC class II in TLR4+/+ BMDCs was not observed in TLR4-/- BMDCs. Furthermore, FAP induced DC-mediated CD8+ T cell proliferation and cytotoxic T lymphocyte (CTL) activity, and suppressed tumor growth with DC-based tumor vaccination in EG7 thymoma murine model. Taken together, these results indicate that the TLR4 agonist, FAP, a potential immunoadjuvant for DC-based cancer vaccination, improves the DC-based immune response via the TLR4 signaling pathway.
*Adhesins, Bacterial/genetics/metabolism ; Animals ; CD8-Positive T-Lymphocytes/metabolism ; *Cancer Vaccines/therapeutic use ; Cell Proliferation ; Cytokines/metabolism ; Dendritic Cells/*cytology ; Disease Models, Animal ; Gene Expression Regulation ; Glycogen Synthase Kinase 3/metabolism ; Humans ; Mice ; Mice, Inbred C57BL ; Mycobacterium avium/genetics/metabolism ; Paratuberculosis/metabolism ; Protein Binding ; Signal Transduction ; T-Lymphocytes, Cytotoxic/metabolism ; *Thymoma/genetics/metabolism ; *Toll-Like Receptor 4/agonists/genetics/metabolism

BACKGROUNDIt has been reported that CD8(+) regulatory cells could be induced upon oral tolerance. The purpose of this study was to investigate the changes of CD8α(+) T cells in dextran sulfate sodium (DSS)-induced colitis mice pretreated by oral immune regulation.

METHODSThe effects of five low oral doses of colitis-extracted proteins (CEP) on colitis were evaluated by clinical manifestation and histological lesions. The percentages of CD8α(+) T cells gating on CD3(+) T cells were evaluated in the gut-associated lymphoid tissues (GALT) and the spleens by flow cytometry. Differences between the two groups were compared by Student's t test or Mann-Whitney U test.

RESULTSCompared to bovine serum albumin (BSA)-fed control mice, administration of CEP resulted in marked alleviation of colitis. The proportion of CD8α(+) T cells, not only in intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs) of the large intestine (LI) but also in spleen from CEP-fed colitis mice, was significantly higher than that from BSA-fed colitis mice (LI-IELs: (71.5 ± 5.4)% vs. (60.1 ± 4.3)%, P < 0.01; LI-LPLs: (60.7 ± 5.2)% vs. (51.9 ± 4.7)%, P < 0.01; spleen: (24.1 ± 3.6)% vs. (20.3 ± 4.1)%, P < 0.05; n = 8). Mucosal repair in repair-period mice five days after termination of DSS treatment was also accompanied by an increase of CD8α(+) T cells in large intestinal mucosal lymphocytes (LI-IELs: (72.1 ± 3.7)% vs. (61.5 ± 4.5)%, P < 0.01; LI-LPLs: (62.1 ± 5.7)% vs. (52.7 ± 3.6)%, P < 0.01; n = 8). The proportion of CD3(+) T cells increased in Peyer's patches (PPs) and decreased in mesenteric lymph nodes (MLNs) from colitis mice compared to untreated mice, whereas the change pattern of CD3(+) T cells in PPs and MLNs from CEP-fed colitis mice was just on the contrary.

CONCLUSIONImprovement of DSS-induced colitis resulted from oral immune regulation is associated with an increase in CD8α(+) T cells in spleen and large intestinal mucosa.

Administration, Oral ; Animals ; CD8-Positive T-Lymphocytes ; metabolism ; Colitis ; chemically induced ; complications ; Dextran Sulfate ; toxicity ; Flow Cytometry ; Lymphocytes ; cytology ; metabolism ; Male ; Mice ; Mice, Inbred BALB C ; Proteins ; administration & dosage ; immunology ; Spleen ; cytology ; metabolism

OBJECTIVETo investigate the quantity and the pathway to damage hematopoietic cells of CD8+CD25+ and CD8+ HLA-DR+ effector T cells in peripheral blood (PB) of severe aplastic anemia(SAA) patients and explore the immunopathogenesis of SAA.

METHODSThe quantity of CD8+ CD25+ and CD8+ HLA-DR+ cells in PB and the expressions of perforin, granzyme B, tumor necrosis factor-beta (TNF-beta) and FasL in 29 SAA (14 untreated and 15 recovered) patients and 12 normal controls were analyzed by flow cytometry.

RESULTSThe fraction of CD8+ CD25+ T cells in CD8+ T cells was (3.67 +/- 2.58)% in untreated SAA patients, (5.19 +/- 4. 29)% in recovered patients and (4.84 +/- 2.31)% in normal controls, and that of CD8+ CD25+ T cells in CD3+ cells in the three groups was (2.25 +/- 1.35)%, (2.98 +/- 1.35)% and (2.11 +/- 1.88)%, respectively. They had no statistic difference among the 3 groups (P >0.05). The fraction of CD8+ HLA-DR+ T cells in CD8+ T cells was (39.30 +/- 8.13)% in untreated patients, which was significantly higher than that in recovered patients [(20.65 +/- 5.38)%] and controls [(18.34 +/- 6.68)%] (P<0.001), while there was no statistic difference between the latter two groups (P>0.05). CD8+ HLA-DR+ T cells in CD3+ cells was (27.81 +/- 7.10)% in untreated group, which was significantly higher than that of recovered group [(12.02 +/- 3.03)%] and controls [(8.50 +/-2.33)%] (P<0.01). And that in recovered group was higher than that in control group (P<0.05). The expressions of perforin, granzyme B, TNF-beta and FasL of CD8+ HLA-DR+ T cells in untreated group were 8.51%, 96.08%, 72.11% and 94.25% respectively, which were higher than those in recovered group (1.78%, 85.20%, 34.38% and 51.20%) and controls (1.86%, 82.09% ,17.92% and 32.91%). There was no statistic difference between recovered patients and controls (P>0.05).

CONCLUSIONThere were elevated quantity of CD8+ HLA-DR+ T cells and high expressions of perforin, granzyme B, TNF-beta and FasL in SAA, which might contribute to the bone marrow failure.

Adolescent ; Adult ; Anemia, Aplastic ; blood ; metabolism ; pathology ; CD8-Positive T-Lymphocytes ; cytology ; Case-Control Studies ; Child ; Fas Ligand Protein ; metabolism ; Female ; Granzymes ; metabolism ; Humans ; Lymphocyte Count ; Lymphotoxin-alpha ; metabolism ; Male ; Middle Aged ; Perforin ; metabolism ; Young Adult

PURPOSE: Postinfectiously irritable bowel syndrome (PI-IBS) develops in 3-30% of individuals with bacterial gastroenteritis. Recent studies demonstrated increases in inflammatory components in gut mucosa of PI-IBS patients even after complete resolution of infection. We aimed to investigate histological changes in colon and rectum of PI-IBS subjects after long term period of infection. MATERIALS AND METHODS: We recruited PI-IBS subjects who had been diagnosed IBS after complete resolution of enteritis caused by shigellosis outbreak 3 years earlier. We compared unmatched four groups, PI-IBS (n = 4), non PI-IBS (n = 7), D-IBS (n = 7, diarrhea predominant type) and healthy controls (n = 10). All of them underwent colonoscopic biopsy at three areas, including descending colon (DC), sigmoid colon (SC) and rectum, which were assessed for 5-hydroxytryptamine (5-HT)/peptide YY (PYY)-containing enterochromaffin (EC) cell, intraepithelial (IEL) and lamina propria T lymphocyte (CD3), CD8 lymphocytes, mast cells and CD68/calprotectin+ macrophages. RESULTS: All subjects had no structural or gross abnormalities at colonoscopy. In PI-IBS, 5-HT containing EC cells, PYY containing EC cells, IELs, CD3 lymphocytes, CD8 lymphocytes, mast cells, and CD68 + macrophages were increased compared to control (p < 0.05). In D-IBS, PYY containing EC cells, IELs, and CD3 lymphocytes were increased compared to control (p < 0.05). In PI-IBS, 5-HT containing EC cells tended to increase and PYY containing EC cells, CD8 lymphocytes, mast cells, and CD68+ macrophages were increased compared to non PI-IBS (p < 0.05). Calprotectin + marcrophages were decreased in PI-IBS, non PI-IBS and IBS compared to control. CONCLUSION: The immunoendocrine cells were sporadically increased in PI-IBS, non PI-IBS and D-IBS compared with control. Our findings in a very small number of patients suggest that mucosal inflammation may play a role in long-term PI-IBS, and that other sub-groups of IBS and larger scale studies are needed to confirm this observation.
Adult ; Antigens, CD/metabolism ; Antigens, Differentiation, Myelomonocytic/metabolism ; CD8-Positive T-Lymphocytes/cytology ; Case-Control Studies ; Colon, Descending/pathology ; Colon, Sigmoid/pathology ; Colonoscopy ; Dysentery, Bacillary/*complications ; Enterochromaffin Cells/cytology ; Female ; Humans ; Immunohistochemistry ; Intestinal Mucosa/*pathology ; Irritable Bowel Syndrome/metabolism/*pathology ; Macrophages/cytology ; Male ; Mast Cells/cytology ; Peptide YY/metabolism ; Rectum/pathology ; Serotonin/metabolism

4-1BB, a member of the tumor necrosis factor receptor (TNFR) superfamily, is a major costimulatory receptor that is rapidly expressed on the surface of CD4+ and CD8+ T cells after antigen- or mitogen-induced activation. The interaction of 4-1BB with 4-1BBL regulates immunity and promotes the survival and expansion of activated T cells. In this study, the expression of 4-1BB and 4-1BBL was examined during regeneration of the murine thymus following acute cyclophosphamide-induced involution. Four-color flow cytometry showed that 4-1BB and 4-1BBL were present in the normal thymus and were preferentially expressed in the regenerating thymus, mainly in CD4+CD8+ double-positive (DP) thymocytes. Furthermore, the CD4loCD8lo, CD4+CD8lo and CD4loCD8+ thymocyte subsets, representing stages of thymocyte differentiation intermediate between DP and single-positive (SP) thymocytes, also expressed 4-1BB and 4-1BBL during thymus regeneration but to a lesser degree. Interestingly, the 4-1BB and 4-1BBL positive cells among the CD4+CD8+ DP thymocytes present during thymus regeneration were TCR(hi) and CD69+ unlike the corresponding controls. Moreover, the 4-1BB and 4-1BBL positive cells among the intermediate subsets present during thymus regeneration also exhibited TCRhi/int and CD69+/int phenotypes, indicating that 4-1BB and 4-1BBL are predominantly expressed by the positively selected population of the CD4+CD8+ DP and the intermediate thymocytes during thymus regeneration. RT-PCR and Western blot analyses confirmed the presence and elevated levels of 4-1BB and 4-1BBL mRNA and protein in thymocytes during thymus regeneration. We also found that the interaction of 4-1BB with 4-1BBL promoted thymocyte adhesion to thymic epithelial cells. Our results suggest that 4-1BB and 4-1BBL participate in T lymphopoiesis associated with positive selection during recovery from acute thymic involution.
4-1BB Ligand/genetics/*metabolism ; Animals ; Antigens, CD137/genetics/*metabolism ; CD4-Positive T-Lymphocytes/cytology/metabolism ; CD8-Positive T-Lymphocytes/cytology/metabolism ; Cell Adhesion ; Cell Differentiation ; Cell Line ; Cells, Cultured ; Cyclophosphamide/pharmacology ; Epithelial Cells/cytology ; Gene Expression Regulation ; Immunosuppressive Agents/pharmacology ; Male ; Mice ; Mice, Inbred C57BL ; RNA, Messenger/genetics ; *Regeneration ; T-Lymphocytes/*cytology/metabolism ; Thymus Gland/*cytology/drug effects/*physiology