Functionally distinct T-helper cell phenotypes predict resistance to different types of parasites in a wild mammal.

The adaptive immune system is critical to an effective response to infection in vertebrates, with T-helper (Th) cells pivotal in orchestrating these responses. In natural populations where co-infections are the norm, different Th responses are likely to play an important role in maintaining host health and fitness, a relationship which remains poorly understood in wild animals. In this study, we characterised variation in functionally distinct Th responses in a wild population of Soay sheep by enumerating cells expressing Th-subset specific transcription factors and quantifying Th-associated cytokines. We tested the prediction that raised Th1 and Th2 responses should predict reduced apicomplexan and helminth parasite burdens, respectively. All measures of Th-associated cytokine production increased with age, while Th17- and regulatory Th-associated cytokine production increased more rapidly with age in males than females. Independent of age, sex, and each other, IL-4 and Gata3 negatively predicted gastro-intestinal nematode faecal egg count, while IFN-γ negatively predicted coccidian faecal oocyst count. Our results provide important support from outside the laboratory that Th1 and Th2 responses predict resistance to different kinds of parasites, and illustrate how harnessing specific reagents and tools from laboratory immunology will illuminate our understanding of host-parasite interactions in the wild.

Monoclonal/polyclonal PAX-8, PTH and GATA3 immunohistochemistry in parathyroid lesions.

BACKGROUND: Parathyroid gland (PG) is an endocrine organ which may display different immunohistochemical stainings with chief cells and oxyphilic cells in normal as well as hyperplasic/tumoral lesions. PURPOSE: In this study, we aimed to identify the demographic properties and diagnostic value of the GATA3 antibody, which is a transcription factor in addition to PTH, and of PAX-8 (monoclonal and polyclonal) antibody. METHODS: We have analyzed in detail the cellular components and staining intensities of 46 adenomas all of which contained parathyroid rims, 12 hyperplasia and 5 adjacent non-neoplastic thyroidectomy materials (63 patients, 114 tissues). RESULTS: While no staining was identified in the thyroid tissue, cytoplasmic PTH immunoreactivity was observed in all (100%) normal parathyroid tissues, rim of PGs and hyperplasia, and in 43/46 cases (93.4%) of adenomas. Adenoma and hyperplasia were less stained than normal PG (p < 0.05). We detected GATA3 staining in all cases except for the thyroid (100%). Weak positivity (1+) was most apparent in adenoma cases (p < 0.05). Monoclonal PAX-8 immunoreactivity was not identified in any normal parathyroid tissue and rim of PG but positive immunoreactivity was detected in 83.3% of hyperplasia cases (10/12), 84.8% of adenoma (39/46) and 100% of thyroid tissues (5/5) (p < 0.05). However, polyclonal PAX-8 immunoreactivity was detected in one normal parathyroid tissue (1/5) and seven (7/46) rim of PGs. In cases of hyperplasia and adenoma, positive immunoreactivity was 75% (9/12) and 74% (34/46), respectively. CONCLUSION: In conclusion, we have observed that PTH and GATA3 constitute a much more reliable and sensitive marker for parathyroid and are stained less in adenomas. While monoclonal PAX-8 (MRQ-50) never stains normal parathyroid and rim of PGs, it may help in the differential diagnosis of proliferated parathyroid lesions as a considerably sensitive and relatively specific marker by staining hyperplasic parathyroid, adenomas and the thyroid.

The impact of 17ß-estradiol and progesterone therapy on peripheral blood mononuclear cells of asthmatic patients.

There is a significant fluctuation in clinical symptoms of asthmatic females during their life course, suggesting that the reproductive status and the level of sex hormones may affect the development of asthma and its exacerbation. In this study, we aimed to assess the biological effects of 17ß-estradiol (E2) and progesterone (P4), alone or in combination form, on the transcription factors and production of cytokines in peripheral blood mononuclear cells (PBMCs). PBMCs of the mild-to-moderate asthmatic patients and healthy controls (HCs) were treated with equivalent serum levels of E2 or P4 maintained during hormone replacement therapy (HRT). The expression levels of T-bet, GATA-3, RORγt, PU.1, and Foxp3 were assessed by quantitative PCR. We also measured the concentration of IL-4, IL-9, IL-10, IFN-γ, and TGF-ß in cell culture supernatants using ELISA. IL-4 production and GATA-3 expression levels slightly increased when asthmatic PBMCs were treated with E2 (p < 0.01), P4 (p < 0.01), or E2 + P4 (p < 0.001) compared to the untreated cells. IL-9 secretion (p < 0.001) and PU.1 gene expression levels (p < 0.05) were slightly higher in asthmatic patients' PBMCs before treatment but hormone therapy did not affect the level of them. Although the untreated asthmatic PBMCs produced a lower amount of IFN-γ compared to HCs (p < 0.01), hormone treatment did not affect the levels of IFN-γ secretion in patient groups. Moreover, we did not observe any significant changes in IL-10 and TGF-ß secretion in the supernatant of hormone treated cells. We found that the common applied HRT may faintly increase GATA-3 expression and IL-4 production levels in PBMCs of asthmatic patients and can slightly increase asthma severity.

Indirubin regulates MPL and TNF expression in peripheral blood mononuclear cells from patients with primary immune thrombocytopenia.

Indirubin, a traditional Chinese medicine, is currently used to treat certain autoimmune diseases such as primary immune thrombocytopenia (ITP) in clinics. However, the effects of indirubin on expression of related genes in peripheral blood mononuclear cells (PBMCs) from ITP patients have not been investigated. In the present study, PBMCs were isolated from 19 adult patients with well-characterized active ITP and 20 healthy controls (HCs) and then treated with increasing concentrations of indirubin. The mRNA expression levels of thrombopoietin receptor (MPL), GATA binding protein 3 (GATA3), DNA methyltransferase 3B (DNMT3B), interleukin-6 (IL6), tumor necrosis factor (TNF), and interferon gamma (IFN-γ) were determined by quantitative real-time polymerase chain reaction (PCR). We found that indirubin had no cytotoxic effect on PBMC viability. Significantly lower MPL (p < 0.05) and GATA3 (p < 0.05) expression together with markedly higher IL6 (p < 0.05), TNF (p < 0.0001), and IFN-γ (p < 0.001) mRNA levels were observed in ITP patients compared with HCs. Notably, indirubin significantly enhanced MPL expression and inhibited TNF expression in PBMCs from ITP patients (p < 0.05). In summary, indirubin may play a direct role in thrombopoiesis by activating cellular MPL and normalizing TNF expression to suppress inflammation in ITP. This study may thus improve our understanding of indirubin and provide important information for optimizing therapeutic strategies for ITP patients.

Distinct Alterations in the Composition of Mucosal Innate Lymphoid Cells in Newly Diagnosed and Established Crohn's Disease and Ulcerative Colitis.

BACKGROUND AND AIMS: Innate lymphoid cells [ILC] have been suggested to play a role in inflammatory bowel disease [IBD]. Here, we investigated the ILC compartment in intestinal biopsies and blood from distinct patient groups with Crohn's disease [CD] and ulcerative colitis [UC], either newly diagnosed or with disease established for at least 1 year. This approach allowed us to simultaneously investigate temporal, disease-specific, and tissue-specific changes in ILC composition in IBD. METHODS: ILC subset frequencies, phenotype, and transcription factor profile in blood and intestinal biopsies were investigated by multi-parameter flow cytometry analysis. Endoscopic disease severity was judged using the ulcerative colitis endoscopic index of severity and the simple endoscopic score for Crohn's disease. RESULTS: The frequency of NKp44+ILC3 was decreased in inflamed tissue, both in patients with CD and those with UC, already at the time of diagnosis, and correlated with disease severity. Simultaneously, the frequency of ILC1 was increased in patients with CD, whereas the frequency of ILC2 was increased in patients with UC. However, in patients with established UC or CD, both ILC1 and ILC2 were increased. In contrast to the ILC composition in inflamed tissue, ILC in non-inflamed tissue or blood were unchanged compared with non-IBD controls. Finally, in patients undergoing treatment with an anti-α4ß7 antibody the frequencies of ILC in peripheral blood remained unchanged. CONCLUSIONS: We report both shared and distinct changes in ILC composition depending on diagnosis and disease duration. The alterations in ILC composition in IBD occur selectively at inflamed sites in the gut.

HIV Infection Functionally Impairs Mycobacterium tuberculosis-Specific CD4 and CD8 T-Cell Responses.

Human immunodeficiency virus (HIV) infection is the major risk factor predisposing for Mycobacterium tuberculosis progression from latent tuberculosis infection (LTBI) to tuberculosis disease (TB). Since long-term-treated aviremic HIV-infected individuals remained at higher risk of developing TB than HIV-uninfected individuals, we hypothesized that progression from LTBI to pulmonary TB (PTB) might be due not only to CD4 T-cell depletion but also to M. tuberculosis-specific CD4 T-cell functional impairment. To test this hypothesis, M. tuberculosis-specific T-cell frequencies and cytokine profiles were investigated in untreated Tanzanian individuals suffering from LTBI (n = 20) or PTB (n = 67) and compared to those of untreated M. tuberculosis/HIV-coinfected individuals suffering from LTBI (n = 15) or PTB (n = 10). We showed that HIV infection significantly reduced the proportion of Th2 (interleukin 4 [IL-4]/IL-5/IL-13) producing M. tuberculosis-specific CD4 T cells and IL-2-producing M. tuberculosis-specific CD4 and CD8 T cells in individuals with LTBI or PTB (P < 0.05). Interestingly, the loss of IL-2 production was associated with a significant increase of PD-1 expression on M. tuberculosis-specific CD4 and CD8 T cells (P < 0.05), while the loss of Th2 cytokine production was associated with a significant reduction of Gata-3 expression in memory CD4 T cells (P < 0.05). Finally, we showed that the serum levels of IL-1α, IL-6, C-reactive protein (CRP), IL-23, and IP-10 were significantly reduced in M. tuberculosis/HIV-coinfected individuals with PTB compared to those in HIV-negative individuals with PTB (P < 0.05), suggesting that HIV infection significantly suppresses M. tuberculosis-induced systemic proinflammatory cytokine responses. Taken together, this study suggests that in addition to depleting M. tuberculosis-specific CD4 T cells, HIV infection significantly impairs functionally favorable M. tuberculosis-specific CD4 T-cell responses in Tanzanian individuals with LTBI or PTB.IMPORTANCEMycobacterium tuberculosis and human immunodeficiency virus (HIV) infections are coendemic in several regions of the world, and M. tuberculosis/HIV-coinfected individuals are more susceptible to progression to tuberculosis disease. We therefore hypothesized that HIV infection would potentially impair M. tuberculosis-specific protective immunity in individuals suffering from latent tuberculosis infection (LTBI) or active pulmonary tuberculosis (PTB). In this study, we demonstrated that M. tuberculosis/HIV-coinfected individuals have fewer circulating M. tuberculosis-specific CD4 T cells and that those that remained were functionally impaired in both LTBI and PTB settings. In addition, we showed that HIV infection significantly interferes with M. tuberculosis-induced systemic proinflammatory cytokine/chemokine responses. Taken together, these data suggest that HIV infection impairs functionally favorable M. tuberculosis-specific immunity.

[Up-regulation of atrial natriuretic peptide and GATA3 levels in peripheral blood of children with respiratory syncytial virus bronchiolitis].

Objective To investigate the relationship between changes in atrial natriuretic peptide (ANP) signal and GATA3 expression in peripheral blood of children with bronchiolitis, and to explore the possible mechanism of ANP signal in the pathogenesis of bronchiolitis.Methods 20 normal children, 16 children with mild bronchiolitis, and 14 medium-severe children were enrolled. ELISA was used to detect the level of ANP and interleukin-4(IL-4) in plasma. Real-time fluorescent quantitative PCR was performed to determine the mRNA expression of natriuretic peptide receptor A(NPRA)and GATA3 in peripheral blood mononuclear cells(PBMCs) .Western blot analysis was used to determine the protein expression of NPRA and GATA3. Results As the degree of inflammation of bronchiolitis increases, the level of ANP and IL-4 in plasma increased significantly, and the mRNA and protein expression of NPRA and GATA3 in PBMCs also increased. Conclusion The levels of ANP, NPRA, IL-4 and GATA3 increased in peripheral blood of children with bronchiolitis.

The Imbalance of FOXP3/GATA3 in Regulatory T Cells from the Peripheral Blood of Asthmatic Patients.

BACKGROUND: Treg cells play an important role in the pathogenic progress of asthma. OBJECTIVE: To address the alterations of Treg cells in asthma. METHODS: Proliferation-and function-associated markers of Treg cells along with the percentage of Treg cells producing some cytokine from asthmatics and healthy subjects were analyzed by flow cytometry. Besides, the expressions of USP21 and PIM2 in Treg cells were measured by cell immunochemistry after Treg cells were sorted. RESULTS: Treg cells from asthmatic patients showed lower proliferation activity and were more likely to be apoptotic. These cells expressed lower levels of GITR, CTLA-4, Nrp-1, and IL-10 compared to those from the healthy control. Th2-like Treg cells increased in asthmatic patients, while the percentage of IFN-r+ Treg cells was similar between two groups. Moreover, the percentage of IL-4+ Treg cells is related to the asthma control. Treg cells from asthmatic patients expressed more FOXP3 as well as GATA3; the expression level of GATA3 negatively correlated with FEV1%pred. Increased expressions of USP21 and PIM2 in Treg cells from asthmatic patients were found. CONCLUSION: Treg cells decreased in asthmatic patients, with an impaired immunosupression function and a Th2-like phenotype, which may be due to overexpression of GATA3 and FOXP3, regulated by USP21 and PIM2, respectively.

[Effect of Acupuncture on the Expression of Transcription Factor T-bet/GATA-3 in Plasma of Rats with Chronic Fatigue Syndrome].

OBJECTIVE: To observe the effect of acupuncture on the expression of T-box expressed in T cell (T-bet)/GATA binding factor-3 (GATA-3) in plasma of rats with chronic fatigue syndrome (CFS) and explore the mechanism of acupuncture treatment for CFS. METHODS: Forty-eight healthy male SD rats were randomly divided into blank control group, CFS model group, acupuncture group, and ginsenoside group (12 rats in each group). CFS rat model was established by combining restriction and cold water swimming. Acupuncture was applied to "Baihui"(GV 20), "Guanyuan" (CV 4) and "Zusanli" (ST 36, bilate-ral) acupoints, once a day for two weeks. The ginsenoside group was gavage administrated with ginsenoside, once a day for two weeks. After 14 days, behavioural changes were observed, and the expression levels of T-bet/GATA-3 genes in plasma were detected by RT-PCR. RESULTS: Compared with the blank control group, the time for immobility of forced suspensory test was signi-ficantly longer (P<0.05) and the time for exhaustive swimming was significantly shortened (P<0.05) in the CFS model group. Compared with the model group, the two indexes above-mentioned were reversed (P<0.05) both in the acupuncture group and the ginsenoside group, and the effects in the acupuncture group were more significant than those in the ginsenoside group (P<0.05). Compared with the blank control group, the expression level of T-cell transcription factor T-bet gene in plasma was higher in the CFS model group (P<0.05), companied with lower GATA-3 gene expression (P<0.05). The ratio of T-bet/GATA-3 was higher in the model group than in the blank control group(P<0.05). Compared with the CFS model group, all the indexes above-mentioned were reversed (P<0.05) in the two treatment groups. Acupuncture group showed a better effect on reducing T-bet gene expression than the ginsenoside group (P<0.05). CONCLUSIONS: Acupuncture can decrease the expression level of T-bet gene while increase the expression of GATA-3 gene, which may be associated with its role in treating CFS.

[γ-secretase inhibitor MW167 reduces the level of GATA3 in peripheral blood mononuclear cells in children with respiratory syncytial virus bronchiolitis].

Objective To study the changes of GATA3 in peripheral blood mononuclear cells (PBMCs) of children with respiratory syncytial virus (RSV) bronchiolitis after γ-secretase inhibitor (GSI) MW167 blocks Notch signaling. Methods The study enrolled 30 patients with RSV bronchiolitis and 25 normal controls. PBMCs were separated and divided into normal control group, RSV group, and MW167 treated group. The level of interleukin-4 (IL-4) in supernatant was detected by ELISA; level of GATA3 mRNA was determined by real-time fluorescent quantitative PCR; and the expressions of Notch1 intracellular domain (NICD) and GATA3 proteins were examined by Western blotting. Results Compared with RSV group, the levels of IL-4 decreased, and the levels of GATA3 mRNA, NICD and GATA3 proteins also significantly decreased in MW167 treated group. Conclusion GSI can block the Notch signaling pathway and decrease the level of GATA3.

Association between cytokine profile and transcription factors produced by T-cell subsets in early- and late-onset pre-eclampsia.

Pre-eclampsia (PE) is an obstetric pathology characterized by abnormal activation of the innate and adaptive immune systems dependent on the imbalance of T helper subsets. The present study aimed to evaluate the gene and protein expression of T helper type 1 (Th1)/Th2/Th17/regulatory T (Treg) cell transcription factors in peripheral blood lymphocytes from pregnant women with PE employing quantitative RT-PCR and flow cytometry techniques, as well as the cytokine profile produced by these CD4+ T-cell subsets in the plasma of pregnant women with PE, classified as early-onset PE (n = 20), late-onset PE (n = 20) and normotensive pregnant women (n = 20). Results showed a higher percentage of CD4+ T cells expressing the RORc transcription factor (Th17) and a lower percentage of cells expressing FoxP3 (Treg) in women with early-onset PE compared with late-onset PE and normotensive groups. A lower gene expression of GATA-3 transcription factor was detected in cells of women with early-onset PE compared with the late-onset PE group. Endogenous plasma levels of interleukin-6 (IL-6), IL-17 and tumour necrosis factor-α were significantly higher in the early-onset PE group than in the late-onset PE and normotensive groups, whereas IL-4 (Th2 profile) and IL-22 (Th17 profile), were not significantly different between the studied groups. The endogenous levels of transforming growth factor-ß and IL-10 were significantly lower in the pre-eclamptic than in the normotensive groups of the same gestational age, with a significant difference between early- and late-onset PE. The results show that in women with PE there is an imbalance between inflammatory and anti-inflammatory profiles in CD4+ T-cell subsets, with polarization to Th17 profiles in the early-onset PE, considered as the severe form of PE.

Role of Th1/Th2 cells and related cytokines in autoimmune hepatitis.

BACKGROUND/AIMS: Dysregulation of T cell response is thought to play an important role in the immunopathogenesis of autoimmune hepatitis. However, no consensus has yet been reached regarding the implications of a distinct T cell subset in the pathogenesis of this progressive liver disease. Therefore, T-bet and GATA-3 expression was examined in patients with autoimmune hepatitis (AIH) and in healthy controls. Moreover, the profile of Th1 (IFN-γ) and Th2 (IL-4) cytokine gene expression was analyzed. MATERIALS AND METHODS: Levels of mRNA transcripts were measured in peripheral blood mononuclear cells (PBMCs) using a two-step reverse transcription quantitative real-time polymerase chain reaction with SYBR Green. RESULTS: T-bet and IFN-γ mRNA expression was significantly higher in AIH patients compared to healthy controls (p<0.05), whereas no differences were observed for either GATA-3 or IL-4 mRNA expression (p>0.05). CONCLUSION: Alterations in the Th1/Th2 cell balance may be responsible for both disease progression and the resulting complications.

Cross-fostering increases TH1/TH2 expression in a prenatal dexamethasone exposure rat model.

BACKGROUND: Prenatal dexamethasone exposure has been reported to increase allergy potential in childhood possibly by interference with normal immunological development in utero. This study investigated the effects of prenatal dexamethasone on T helper cell immune responses in a rat model. METHODS: Pregnant rats received either dexamethasone 0.1 mg/kg/day or normal saline from gestational day 14-21. Off-springs were cared for by their biological mother, or cross-fostered by the opposing group. Spleen and blood samples were collected at post-natal day 7 and 120 and tested for mRNA expression and plasma cytokine levels of Th1/Th2/Th17 immune response. RESULTS: Both Th1 (T-bet) and Th2 (GATA-3) mRNA expression were shown to have a significant increase in the prenatal dexamethasone exposure group at day 120 (p<0.05). The plasma levels for Th1 (IFNγ and IL-2) and Th2 (IL-4, IL-5, IL-13) were found to have no significant differences between the two group (p>0.05). The mRNA expression of Th17 (RORγt) showed a significant decrease at post-natal day 120 as well as the plasma level of IL-17A at day 7 (11.21±1.67 vs. 6.23±1.06 pg/ml, p = 0.02). Cross-fostering by a dexamethasone exposed mother resulted in a significant increase in Th1/Th2 mRNA expression (p<0.05) and decrease of Th17. CONCLUSIONS: Prenatal dexamethasone exposure increased Th1, Th2 and decreased Th17 expression. Cross-fostering by a dexamethasone exposed mother results in more prominent increase of Th1 and Th2 expression.

Increased interleukin-27 promotes Th1 differentiation in patients with chronic immune thrombocytopenia.

Chronic immune thrombocytopenia (cITP) is an autoimmune disease with disturbed cytokine profile. Although plasma levels of IL-27 are shown to be associated with cITP, its association with T cell subsets has not been studied. The objective of this study was to study the association between IL-27 and different T cell subsets in patients with cITP. Heparinized blood was collected from 31 patients with cITP and 36 healthy controls (platelet count <100 × 10(9)/l and 103-280 × 10(9)/l, respectively). The percentage of Th1, Th2 and Th17 cells in peripheral blood mononuclear cells (PBMCs) were enumerated by flow cytometry, and the mRNA levels of IL-27, T-bet, GATA-3 and retinoid-related orphan receptor gamma (RORγt) by real-time reverse transcriptase polymerase chain (RT-PCR). Plasma cytokine levels of IL-27, interferon-gamma (IFN-γ), IL-4 and IL-17A were estimated by flow cytometrix. The effect of exogenous recombinant IL-27(rhIL-27) on the differentiation of T cells into Th1, Th2 and Th17 cells was investigated by cell culture. The percentage of Th1 and Th17 cells and the plasma concentration and mRNA levels of IL-27 were significantly higher in cITP patients compared with healthy controls. Plasma levels of IL-27 correlated positively with percentage of Th1 cells in patients with cITP. Exogenous (rhIL-27) could significantly up-regulate the percentage of Th1 cells and down-regulate Th2 cells in vitro. Th17 cells were reduced in the presence of (rhIL-27) in controls but had no effect in patients with cITP. The up-regulation of IL-27 might cause Th1 differentiation and might be involved in the pathophysiology of cITP.

Adequate Th2-type response associates with restricted bacterial growth in latent mycobacterial infection of zebrafish.

Tuberculosis is still a major health problem worldwide. Currently it is not known what kind of immune responses lead to successful control and clearance of Mycobacterium tuberculosis. This gap in knowledge is reflected by the inability to develop sufficient diagnostic and therapeutic tools to fight tuberculosis. We have used the Mycobacterium marinum infection model in the adult zebrafish and taken advantage of heterogeneity of zebrafish population to dissect the characteristics of adaptive immune responses, some of which are associated with well-controlled latency or bacterial clearance while others with progressive infection. Differences in T cell responses between subpopulations were measured at the transcriptional level. It was discovered that a high total T cell level was usually associated with lower bacterial loads alongside with a T helper 2 (Th2)-type gene expression signature. At late time points, spontaneous reactivation with apparent symptoms was characterized by a low Th2/Th1 marker ratio and a substantial induction of foxp3 reflecting the level of regulatory T cells. Characteristic gata3/tbx21 has potential as a biomarker for the status of mycobacterial disease.

Research on the roles of transcription factors T-bet and GATA-3 in aplastic anemia.

BACKGROUND: Aplastic anemia (AA) is a type of bone marrow hematopoietic system disease. The immune mediated hematopoietic inhibition is recognized as the most common pathogenesis of AA. However, the roles of the T-bet/GATA-3-mediated cell immune disorder in aplastic anemia (AA) is still unknown. METHODS: Experimental samples were obtained from 27 patients with AA, including 15 cases of severe AA (SAA) and 12 cases of immune mediated AA (MAA), and 25 healthy volunteers (control group). The secretory levels of IFN-gamma and IL-4 cytokines were determined by ELISA. The mRNA expression levels of transcription factors T-bet, GATA-3, and FoxP3 were measured in PBMCs by RT-PCR. Th1, Th2, and T lymphocyte subsets were detected in peripheral blood by flow cytometry. RESULTS: Compared to the healthy control group, the expression of T-bet mRNA and the percentage of Th1-type cells in the AA group significantly increased (p < 0.01), while the expression of GATA-3 and FoxP3 mRNA and the percentage of Th2-type cells decreased sharply (p < 0.05, p < 0.01). Compared with MAA, the expression of T-bet mRNA and the percentage of Th1-type cells increased significantly in SAA (p < 0.01); meanwhile, the expression of GATA-3 mRNA and the proportion of Th2-type cells decreased noticeably (p < 0.05, p < 0.01). Particularly, the percentage of CD3+ and CD3+CD8+ T cells in the AA group increased (p < 0.05), while the percentage of CD3+CD4+, CD4+CD25+, and CD4+CD8+ cells decreased (p < 0.05, p < 0.01). CONCLUSIONS: Abnormal expression of the transcription factors T-bet and GATA-3 contributes to the imbalance of Thl/Th2 lymphocytes associated with immune dysfunction, leading to the development and progression of AA.

Role of CD4(+) and CD8α(+) T cells in protective immunity against Edwardsiella tarda infection of ginbuna crucian carp, Carassius auratus langsdorfii.

Edwardsiella tarda is an intracellular pathogen that causes edwardsiellosis in fish. Our previous study suggests that cell-mediated immunity (CMI) plays an essential role in protection against E. tarda infection. In the present study, we adoptively transferred T-cell subsets sensitized with E. tarda to isogenic naïve ginbuna crucian carp to determination the T-cell subsets involved in protecting fish from E. tarda infection. Recipients of CD4(+) and CD8α(+) cells acquired significant resistance to infection with E. tarda 8 days after sensitization, indicating that helper T cells and cytotoxic T lymphocytes plays crucial roles in protective immunity to E. tarda. Moreover, transfer of sensitized CD8α(+) cells up-regulated the expression of genes encoding interferon-γ (IFN-γ) and perforin, suggesting that protective immunity to E. tarda involves cell-mediated cytotoxicity and interferon-γ-mediated induction of CMI. The results establish that CMI plays a crucial role in immunity against E. tarda. These findings provide novel insights into understanding the role of CMI to intracellular pathogens of fish.