CD3+T, CD4+T, CD8+T, and CD4+T/CD8+T Ratio and Quantity of γδT Cells in Peripheral Blood of HIV-Infected/AIDS Patients and Its Clinical Significance.

OBJECTIVE: To investigate the quantity of CD4+T, CD4+T, CD8+T, and γδT cells in peripheral blood of HIV-infected/AIDS patients as well as to explore the possible role of CD4/CD8 ratio and γδT cells in the progression of HIV/AIDS, aimed at providing evidence for the diagnosis and treatment of AIDS. METHODS: The quantity levels of CD3+T cells, CD4+T cells, CD8+T cells, and γδT cells in peripheral blood of 46 HIV-infected/AIDS patients and 30 healthy controls were detected by using flow cytometry. RESULTS: The count of CD3+T, CD4+T, CD8+T, and γδT cells ( x ¯ ± s , A/µl) in the peripheral blood was 1183.64 ± 132.58, 278.39 ± 122.38, 863.13 ± 82.38, and 22.53 ± 1.74 in the experimental group as well as 1456.46 ± 124.37, 788.74 ± 189.67, 569.61 ± 46.49, and 10.96 ± 0.28 in the control group, respectively. The p values of the two groups were <0.005 after the t-test, revealing a statistically significant difference. The proportion of CD3+T, CD4+T, CD8+T, and γδT cells in total lymphocytes in the two groups ( x ¯ ± s , %) was 71.83 ± 5.37, 13.39 ± 2.23, 62.93 ± 5.81, and 3.67 ± 0.87 in the experimental group, respectively. In the control group, the values were expressed as 66.72 ± 5.48, 42.77 ± 3.38, 31.41 ± 3.62, and 1.73 ± 0.36, respectively. After performing the t-test, p values in the two groups were <0.005 except CD3+T, with statistically significant differences. Besides, CD4/CD8 was 0.33 ± 0.11 in the experimental group and 1.48 ± 0.29 in the control group, t = 26.528, p < 0.001, exhibiting a significant statistical difference. CONCLUSION: HIV infection induces the activation and proliferation of CD8+T and γδT cells, contributing to the decrease of CD4+T cells, while CD8+T and γδT cells are involved in the immune response and tissue damage after HIV infection.

Altered distributions and functions of natural killer T cells and γδ T cells in neonates with neonatal encephalopathy, in school-age children at follow-up, and in children with cerebral palsy.

We enumerated conventional and innate lymphocyte populations in neonates with neonatal encephalopathy (NE), school-age children post-NE, children with cerebral palsy and age-matched controls. Using flow cytometry, we demonstrate alterations in circulating T, B and natural killer cell numbers. Invariant natural killer T cell and Vδ2+ γδ T cell numbers and frequencies were strikingly higher in neonates with NE, children post-NE and children with cerebral palsy compared to age-matched controls, whereas mucosal-associated invariant T cells and Vδ1 T cells were depleted from children with cerebral palsy. Upon stimulation ex vivo, T cells, natural killer cells and Vδ2 T cells from neonates with NE more readily produced inflammatory cytokines than their counterparts from healthy neonates, suggesting that they were previously primed or activated. Thus, innate and conventional lymphocytes are numerically and functionally altered in neonates with NE and these changes may persist into school-age.

γδ T cell frequencies are altered in HIV positive pregnant South African women and are associated with preterm birth.

BACKGROUND: Preterm birth is the leading cause of neonatal and child mortality worldwide. Maternal HIV infection and antiretroviral treatment (ART) increase the rate of preterm birth, but the underlying mechanisms remain unknown, limiting progress in prediction, prevention and treatment. While overall γδ T cell levels remain constant, acute HIV infection is associated with a depletion of the Vδ2 subset and an increase in the Vδ1 subset, which do not return to baseline with ART. γδ T cells have also been implicated in adverse pregnancy outcomes and we therefore investigated the potential association between maternal HIV infection, peripheral γδ T cell frequencies and preterm birth. METHODS: Study participants were HIV positive (n = 47) and HIV negative (n = 45) women enrolled in a prospective pregnancy cohort study at Chris Hani Baragwanath Academic Hospital in Soweto, South Africa. Women were enrolled in early pregnancy and gestational age was accurately determined by first trimester ultrasound scan. Peripheral blood samples were collected in each trimester and peripheral blood mononuclear cells isolated. Frequencies of γδ T cells, Vδ1+ and Vδ2+ γδ T cell subsets, and CCR6 chemokine receptor expression were determined by flow cytometry. RESULTS: Total γδ T cell levels were similar between HIV positive and HIV negative women throughout pregnancy. However, in each trimester maternal HIV infection was associated with reduced levels of the Vδ2+ subset and increased levels of the Vδ1+ subset, leading to a reversal of the Vδ1/Vδ2 ratio. Timing of ART initiation among HIV positive women did not affect levels of γδ T cells, the Vδ1+ and Vδ2+ subsets, or the Vδ1/Vδ2 ratio. Importantly, preterm birth was associated with lower total γδ T cell levels in early pregnancy and γδ T cell frequencies were lowest in HIV positive women who delivered preterm. Moreover, in the first trimester the proportion of Vδ1+ T cells that were CCR6+ was significantly reduced in HIV+ women and women who delivered preterm, resulting in the lowest proportion of CCR6+ Vδ1 T cells in HIV positive women who delivered preterm. CONCLUSIONS: Our findings suggest that altered γδ T cell frequencies may link maternal HIV infection and preterm birth. γδ T cell frequencies in early pregnancy may serve as predictive biomarkers to identify women at risk of delivering preterm.

Dissection of the Human T-Cell Receptor γ Gene Repertoire in the Brain and Peripheral Blood Identifies Age- and Alzheimer's Disease-Associated Clonotype Profiles.

The immune system contributes to neurodegenerative pathologies. However, the roles of γδ T cells in Alzheimer's disease (AD) are poorly understood. Here, we evaluated somatic variability of T-cell receptor γ genes (TRGs) in patients with AD. We performed deep sequencing of the CDR3 region of TRGs in patients with AD and control patients without dementia. TRG clones were clearly detectable in peripheral blood (PB) and non-neuronal cell populations in human brains. TRG repertoire diversity was reduced during aging. Compared with the PB, the brain showed reduced TRGV9 clonotypes but was enriched in TRGV2/4/8 clonotypes. AD-associated TRG profiles were found in both the PB and brain. Moreover, some groups of clonotypes were more specific for the brain or blood in patients with AD compared to those in controls. Our pilot deep analysis of T-cell receptor diversities in AD revealed putative brain and AD-associated immunogenic markers.

Incidence and outcomes of rare T cell lymphomas from the T Cell Project: hepatosplenic, enteropathy associated and peripheral gamma delta T cell lymphomas.

The T Cell Project was the largest prospective trial to explore the incidence, treatment patterns, and outcomes for T cell lymphomas. The rare subtypes of T cell lymphomas, including hepatosplenic T cell lymphoma (HSTCL), enteropathy associated T cell lymphoma (EATL), and peripheral gamma delta T cell lymphomas (PGDTCLs) are poorly represented in most studies and there is little data regarding treatment patterns. We report results from 115 patients with hepatosplenic (n = 31), enteropathy associated (n = 65), and PGDTCLs (n = 19). While anthracycline regimens were most commonly used as first line therapy, response rates ranged from 20%-40% and were suboptimal for all groups. Autologous stem cell transplantation was performed as a consolidation in first remission in a small number of patients (33% of HSTCL, 7% of EATL, and 12% of PGDTCL), and four patients with HSTCL underwent allogeneic stem cell transplantation in first remission. The progression free survival at 3 years ranged from 28%-40% for these rare subtypes, and the overall survival at 3 years was most favorable for PGDTCL (70%). These data highlight the need for novel treatment approaches for rare subtypes of T cell lymphomas and for their inclusion in clinical trials.

Distinct phenotype and function of circulating Vδ1+ and Vδ2+ γδT-cells in acute and chronic hepatitis B.

Hepatitis B virus (HBV) persists with global and virus-specific T-cell dysfunction, without T-cell based correlates of outcomes. To determine if γδT-cells are altered in HBV infection relative to clinical status, we examined the frequency, phenotype and function of peripheral blood Vδ1+ and Vδ2+γδT-cells by multi-parameter cytometry in a clinically diverse North American cohort of chronic hepatitis B (CHB), acute hepatitis B (AHB) and uninfected control subjects. We show that circulating γδT-cells were comprised predominantly of CD3hiCD4- Vδ2+γδT-cells with frequencies that were 2-3 fold higher among Asian than non-Asian Americans and inversely correlated with age, but without differences between CHB, AHB and control subjects. However, compared to control subjects, CHB was associated with increased TbethiEomesdim phenotype in Vδ2+γδT-cells whereas AHB was associated with increased TbethiEomesdim phenotype in Vδ1+γδT-cells, with significant correlations between Tbet/Eomes expression in γδT-cells with their expression of NK and T-cell activation and regulatory markers. As for effector functions, IFNγ/TNF responses to phosphoantigens or PMA/Ionomycin in Vδ2+γδT-cells were weaker in AHB but preserved in CHB, without significant differences for Vδ1+γδT-cells. Furthermore, early IFNγ/TNF responses in Vδ2+ γδT-cells to brief PMA/Ionomycin stimulation correlated inversely with serum ALT but not HBV DNA. Accordingly, IFNγ/TNF responses in Vδ2+γδT-cells were weaker in patients with CHB with hepatitis flare compared to those without hepatitis flares, and this functional deficit persisted beyond clinical resolution of CHB flare. We conclude that circulating γδT-cells show distinct activation and differentiatiation in acute and chronic HBV infection as part of lymphoid stress surveillance with potential role in clinical outcomes.

Early Pregnancy Human Decidua is Enriched with Activated, Fully Differentiated and Pro-Inflammatory Gamma/Delta T Cells with Diverse TCR Repertoires.

Pregnancy is a state where high and stage-dependent plasticity of the maternal immune system is necessary in order to equilibrate between immunosuppression of harmful responses towards the fetus and ability to fight infections. TCR γδ cells have been implicated in the responses in infectious diseases, in the regulation of immune responses, and in tissue homeostasis and repair. The variety of functions makes γδ T cells a particularly interesting population during pregnancy. In this study, we investigated the proportion, phenotype and TCR γ and δ repertoires of γδ T cells at the maternal⁻fetal interface and in the blood of pregnant women using FACS, immunohistochemistry and spectratyping. We found an enrichment of activated and terminally differentiated pro-inflammatory γδ T-cell effectors with specific location in the human decidua during early pregnancy, while no significant changes in their counterparts in the blood of pregnant women were observed. Our spectratyping data revealed polyclonal CDR3 repertoires of the δ1, δ2 and δ3 chains and γ2, γ3, γ4 and γ5 chains and oligoclonal and highly restricted CDR3γ9 repertoire of γδ T cells in the decidua and blood of pregnant women. Early pregnancy induces recruitment of differentiated pro-inflammatory γδ T-cell effectors with diverse TCR repertoires at the maternal⁻fetal interface.

Multivariate Computational Analysis of Gamma Delta T Cell Inhibitory Receptor Signatures Reveals the Divergence of Healthy and ART-Suppressed HIV+ Aging.

Even with effective viral control, HIV-infected individuals are at a higher risk for morbidities associated with older age than the general population, and these serious non-AIDS events (SNAEs) track with plasma inflammatory and coagulation markers. The cell subsets driving inflammation in aviremic HIV infection are not yet elucidated. Also, whether ART-suppressed HIV infection causes premature induction of the inflammatory events found in uninfected elderly or if a novel inflammatory network ensues when HIV and older age co-exist is unclear. In this study we measured combinational expression of five inhibitory receptors (IRs) on seven immune cell subsets and 16 plasma markers from peripheral blood mononuclear cells (PBMC) and plasma samples, respectively, from a HIV and Aging cohort comprised of ART-suppressed HIV-infected and uninfected controls stratified by age (≤35 or ≥50 years old). For data analysis, multiple multivariate computational algorithms [cluster identification, characterization, and regression (CITRUS), partial least squares regression (PLSR), and partial least squares-discriminant analysis (PLS-DA)] were used to determine if immune parameter disparities can distinguish the subject groups and to investigate if there is a cross-impact of aviremic HIV and age on immune signatures. IR expression on gamma delta (γδ) T cells exclusively separated HIV+ subjects from controls in CITRUS analyses and secretion of inflammatory cytokines and cytotoxic mediators from γδ T cells tracked with TIGIT expression among HIV+ subjects. Also, plasma markers predicted the percentages of TIGIT+ γδ T cells in subjects with and without HIV in PSLR models, and a PLS-DA model of γδ T cell IR signatures and plasma markers significantly stratified all four of the subject groups (uninfected younger, uninfected older, HIV+ younger, and HIV+ older). These data implicate γδ T cells as an inflammatory driver in ART-suppressed HIV infection and provide evidence of distinct "inflamm-aging" processes with and without ART-suppressed HIV infection.

Phenotypic Changes and Impaired Function of Peripheral γδ T Cells in Patients With Sepsis.

INTRODUCTION: Recent studies demonstrated the significant loss of gamma delta T (γδ T) cells in patients with sepsis. Given the distinct functions of γδ T cells in human anti-infection immunity, we are interested in evaluating the phenotype and function of peripheral γδ T cells in septic patients and determining their prognostic implication. METHOD: This prospective study has been conducted in three intensive care units of a university hospital. During the period from October 2014 to June 2015, we enrolled 107 patients who were consecutively admitted and diagnosed with severe sepsis or septic shock (excluding previous immunosuppression) and 45 healthy controls. Using flow cytometry, we analyzed the in vivo percentage of γδ T cells in cluster of differentiation (CD)3 cells from peripheral blood mononuclear cells as well as their expression of surface markers (CD69, natural-killer group 2 member D [NKG2D], programmed death receptor 1 [PD-1]) and intracellular cytokines (interferon-γ [IFN-γ], interleukin [IL]-17, IL-10, transforming growth factor-ß [TGF-ß]). Then we further evaluated the different responses of γδ T cells after the antigen stimulation ex vivo by measuring CD69 and IFN-γ expression. Lastly, we conducted the multiple logistic regressions to analyze the risk factor for prognosis. RESULTS: Compared with control group, γδ T cells in septic patients displayed a decrease in percentage, increase in CD69, decrease in NKG2D, and increase in cytokine expression (pro-inflammatory IFN-γ, IL-17, anti-inflammatory IL-10, TGF-ß) in vivo. After the antigen stimulation ex vivo, both CD69 and IFN-γ expression in γδ T cells were significantly lower in septic patients than control group. Importantly, the decrease in CD69 and IFN-γ expression was more pronounced in non-survivors than survivors. Multiple logistic regression analysis revealed that lower expression of IFN-γ after stimulation is a dependent risk factor that associated with patient 28-day death in septic patients (OR: 0.908 [95% CI: 0.853-0.966]). CONCLUSION: Septic patients showed altered phenotype and function of γδ T cells. The impaired IFN-γ expression by γδ T cells after the antigen stimulation is associated with mortality in septic patients.

Proportions of blood-borne Vδ1+ and Vδ2+ T-cells are associated with overall survival of melanoma patients treated with ipilimumab.

Human γδ T-cells possess regulatory and cytotoxic capabilities, and could potentially influence the efficacy of immunotherapies. We analysed the frequencies of peripheral γδ T-cells, including their most prominent subsets (Vδ1+ and Vδ2+ cells) and differentiation states in 109 melanoma patients and 109 healthy controls. We additionally analysed the impact of γδ T-cells on overall survival (OS) calculated from the first dose of ipilimumab in melanoma patients. Higher median frequencies of Vδ1+ cells and lower median frequencies of Vδ2+ cells were identified in patients compared to healthy subjects (Vδ1+: 30% versus 15%, Vδ2+: 39% versus 64%, both p < 0.001). Patients with higher frequencies of Vδ1+ cells (≥30%) had poorer OS (p = 0.043) and a Vδ1+ differentiation signature dominated by late-differentiated phenotypes. In contrast, higher frequencies of Vδ2+ cells (≥39%) were associated with longer survival (p = 0.031) independent of the M category or lactate dehydrogenase level. Patients with decreasing frequencies of Vδ2+ cells under ipilimumab treatment had worse OS and a lower rate of clinical benefit than patients without such decreases. Therefore, we suggest frequencies of both Vδ1+ and Vδ2+ cells as candidate biomarkers for outcome in melanoma patients following ipilimumab. Further studies are needed to validate these results and to clarify whether they represent prognostic associations or whether γδ T-cells are specifically and/or functionally linked to the mode of action of ipilimumab.

[Changes and clinical significance of innate-like lymphocyte subsets in peripheral blood of patients with advanced non-small cell lung cancer].

OBJECTIVE: To investigate the percentages and correlations of innate-like lymphocyte subsets, αßT cells and B2 cells in peripheral blood of patients with non-small cell lung cancer (NSCLC) and normal individuals. METHODS: A total of 16 healthy controls, 5 NSCLC first-visit patients and 15 NSCLC stable-state patients were included to take the peripheral blood samples. Flow cytometry was performed to detect the percentages of invariant natural killer T (iNKT), γδT, B1, αßT and B2 cell subsets in peripheral blood lymphocytes. RESULTS: The percentage of iNKT cells in the stable-state patients was significantly lower than that of the healthy people and first-visit patients. In addition, the percentage of αßT cells in the stable-state patients was significantly higher than that of the healthy people. The fist-visit patients had a markedly higher percentage of γδT cells than the stable-state patients, but a significantly lower percentage of B1 cells than the healthy people. There was an obviously positive correlation between iNKT cells and γδT cells in the stable-state patients. We also found a significantly positive correlation between B1 cells and B2 cells in both stable-state patients and healthy people. CONCLUSION: The percentages of innate-like lymphocyte subsets in patients with NSCLC are in disequilibrium.

Regulatory T, natural killer T and γδ T cells in multiple sclerosis and chronic fatigue syndrome/myalgic encephalomyelitis: a comparison.

BACKGROUND: Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME), and Multiple Sclerosis (MS) may share some similarities in relation to reduced NK cell activity. It is likely that other cells such as regulatory T (Tregs), invariant Natural Killer T (iNKT) and gamma delta T (γδ T) cells may also be dysregulated in CFS/ME and MS. OBJECTIVE: To evaluate and compare specific immune regulatory cells of patients with CFS/ME, patients with MS and healthy controls. METHOD: Sixty three volunteers were included in this study: 24 were CFS/ME patients, 11 were MS patients and 27 were healthy controls. Blood samples were obtained from all participants for flow cytometry analysis of iNKT cells, Tregs and γδ T cell phenotypes. RESULTS: We observed a significant increase in Tregs in the CFS/ME group (p≤0.05) compared to the healthy control group. Total γδ and γδ2 T cells were significantly reduced in MS patients in comparison with the healthy control group. Conversely, CD4+iNKT percentage of iNKT, was significantly increased in the CFS/ME group compared with healthy controls and the double-negative iNKT percentage of iNKT significantly decreased compared with the healthy control group. CONCLUSIONS: This study has not identified any immunological disturbances that are common in both MS and CFS/ME patients. However, the differential expression of cell types between the conditions investigated suggests different pathways of disease. These differences need to be explored in further studies.

(99) Tc-methylene diphosphonate improves rheumatoid arthritis disease activity by increasing the frequency of peripheral γδ T cells and CD4(+) CD25(+) Foxp3(+) Tregs.

AIM: γδ T cells exhibit important functions in the pathogenesis of rheumatoid arthritis (RA). In recent years, numerous studies harnessed the γδ T cell-activating capacity of aminobiphosphonates for the treatment of malignant tumors. As (99) Tc-methylene diphosphonate ((99) Tc-MDP) has long been widely used for the treatment of RA in China with good efficacy, we are interested in whether this drug exerts its therapeutic effect on RA by modulating peripheral γδ T cells of RA patients. OBJECTIVES: To investigate the effect of (99) Tc-MDP on the frequency of γδ T cells and CD4(+) CD25(+) Foxp3(+) Tregs in the peripheral blood of patients with active RA. METHODS: Nineteen patients with active RA were treated with (99) Tc-MDP intravenously at a dose of 20 µg/day consecutively for 10-14 days. Before and after treatment, the main clinical and laboratory parameters for each patient were evaluated. The frequency of CD3(+) γδ(+) T cells and CD4(+) CD25(+) Foxp3(+) Tregs was detected by flow cytometry. Serum levels of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10 and transforming growth factor (TGF)-ß were measured with enzyme-linked immunosorbent assay. RESULTS: After intravenous (99) Tc-MDP therapy, the frequency of peripheral CD3(+) γδ(+) T cells and CD4(+) CD25(+) Foxp3(+) Tregs were significantly elevated, paralleled with decreased serum levels of TNF-α and IL-6 and increased level of serum TGF-ß. The elevation of peripheral CD3(+) γδ(+) T cells was positively correlated with increased serum TGF-ß and decreased disease activity. CONCLUSION: (99) Tc-MDP may improve the activity of RA through upregulating the frequency of peripheral γδ T cells and CD4(+) CD25(+) Foxp3(+) Tregs as well as affecting the serum cytokine environment by increasing TGF-ß and decreasing TNF-α and IL-6.

The longitudinal analysis of large granular lymphocytosis in patients with Philadelphia chromosome-positive leukemia treated with dasatinib.

Dasatinib, a 2nd-generation tyrosine kinase inhibitor (TKI), can specifically induce large granular lymphocytes (LGL) in some patients with Philadelphia chromosome (Ph)-positive leukemia. To investigate the properties of the induced LGLs, we performed prospective and longitudinal analyses. From Feb 2011 to Jan 2013, a total of 17 patients with Ph-positive leukemia who were previously untreated or refractory to imatinib were enrolled. T cell receptor (TCR)-γ/δ gene rearrangements and phenotypic profiles of lymphocytes were examined before and during administration of dasatinib. LGL lymphocytosis was observed in half of the dasatinib-treated cases (LGL+ group), showing a relation to increased achievement of complete cytogenetic response within 6 months. The phenotypes of the increased lymphocytes were revealed to be mostly natural killer cells. In the LGL+ group, clonal TCR-γ gene rearrangements were frequently detected at diagnosis (six of nine cases) and persisted during therapy, compared with only two of eight in the LGL- group. The proportion of regulatory T cells to CD4+ T cells at diagnosis was lower in the LGL+ compared with the LGL- group (median 4.2 vs. 6.6 %), and this disparity was sustained throughout the therapeutic period. These results demonstrate that immunological condition at diagnosis may affect LGL lymphocytosis in some dasatinib-treated patients.

Dynamics of Circulating γδ T Cell Activity in an Immunocompetent Mouse Model of High-Grade Glioma.

Human γδ T cells are potent effectors against glioma cell lines in vitro and in human/mouse xenograft models of glioblastoma, however, this effect has not been investigated in an immunocompetent mouse model. In this report, we established GL261 intracranial gliomas in syngeneic WT C57BL/6 mice and measured circulating γδ T cell count, phenotype, Vγ/Vδ repertoire, tumor histopathology, NKG2D ligands expression, and T cell invasion at day 10-12 post-injection and at end stage. Circulating γδ T cells transiently increased and upregulated Annexin V expression at post-tumor day 10-12 followed by a dramatic decline in γδ T cell count at end stage. T cell receptor repertoire showed no changes in Vγ1, Vγ4, Vγ7 or Vδ1 subsets from controls at post-tumor day 10-12 or at end stage except for an end-stage increase in the Vδ4 population. Approximately 12% of γδ T cells produced IFN-γ. IL-17 and IL-4 producing γδ T cells were not detected. Tumor progression was the same in TCRδ-/- C57BL/6 mice as that observed in WT mice, suggesting that γδ T cells exerted neither a regulatory nor a sustainable cytotoxic effect on the tumor. WT mice that received an intracranial injection of γδ T cells 15m following tumor placement showed evidence of local tumor growth inhibition but this was insufficient to confer a survival advantage over untreated controls. Taken together, our findings suggest that an early nonspecific proliferation of γδ T cells followed by their depletion occurs in mice implanted with syngeneic GL261 gliomas. The mechanism by which γδ T cell expansion occurs remains a subject for further investigation of the mechanisms responsible for this immune response in the setting of high-grade glioma.

Gamma delta T-cell large granular lymphocyte lymphoma in a dog.

A 2-year and 6-month-old female neutered Labrador Retriever with Horner syndrome, megaesophagus, and a mediastinal mass was referred to the Queen Mother Hospital for Animals of the Royal Veterinary College. A large granular lymphocyte (LGL) lymphoma was diagnosed on cytology; flow cytometric analysis revealed a γδ T-cell phenotype (CD3+, CD5+, CD45+, TCRγδ+, CD4-, CD8-, CD34-, CD21-). Chemotherapy was started with a combination of lomustine, vincristine, procarbazine, and prednisolone, followed by bleyomicin. Euthanasia was elected by the owners, due to progressive deterioration and lack of quality of life, 28 days after diagnosis. This is the first cytologic and immunophenotypic characterization of a canine γδ T-cell lymphoma with LGL morphology and probably of mediastinal origin. The role of chemotherapy in delaying the disease progression remains unknown.

Persistent complete remission of acute leukemic-phase CCR4-positive gamma-delta peripheral T-cell lymphoma by autologous stem cell transplantation with mogamulizumab.

Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), frequently shows a poor outcome. Especially, expressions of CC chemokine receptor 4 (CCR4) and γδ T-cell receptor (TCR) are associated with worse prognosis in PTCL-NOS. We here report successful treatment with autologous peripheral blood stem cell transplantation (auto-PBSCT) combined with anti-CCR4 antibody mogamulizumab for a very rare case of CCR4+γδTCR+ PTCL-NOS that coexisted with Hodgkin's lymphoma. PTCL-NOS in this patient progressed to leukemic phase, whereas Hodgkin's lymphoma disappeared with standard chemotherapies within 4 years of the initial diagnosis. Leukemic-phase PTCL-NOS was refractory to several chemotherapies. However, auto-PBSCT following high-dose chemotherapy combined with pre- and post-transplant mogamulizumab, which is a humanized monoclonal antibody to CCR4, provided persistent complete remission of PTCL-NOS, despite residual γδTCR+ in the transplanted stem cell product, suggesting a purging effect of mogamulizumab. At 15 months after transplantation, we also found markedly fewer effector regulatory T cells, which may have contributed to prolonged remission. This case suggests that autologous stem cell transplantation combined with mogamulizumab may have a potential to cure T-cell neoplasms that express CCR4 including leukemic-phase PTCL-NOS.

Correlation of gammadelta-T-cells, Th17 cells and IL-17 in peripheral blood of patients with allergic rhinitis.

BACKGROUD: Gammadelta-T-cells play an important role in the mucosal immune system of the respiratory tract. Th17 cells plays an important role in promoting inflammation and autoimmune diseases. Th17 cells mainly secrete IL-17. However, little information is available on the relation between gammadelta-T-cells and Th17 cells in allergic rhinitis (AR). OBJECTIVE: To explore the correlation between the prevalence of gammadelta-T-cells, the prevalence of Th17 cells and the expression of IL-17 in the peripheral blood of patients with AR. METHODS: Peripheral blood from the AR group (32 cases) and the control group (20 cases) was collected from March 2012 to July 2012. The percentages of gammadelta-T-cells and Th17 cells were measured by flow cytometry, and the levels of IL-17 were measured by ELISA. RESULTS: The percentage of gammadeta-T-cells and Th17 cells in the AR group were significantly higher than those in the control group (P < 0.01). The levels of IL-17 in the AR group were also significantly higher than those in the control group (P < 0.01). There were positive correlations between the gammadelta-T-cell percentage and the Th17 cell percentage in the peripheral blood of AR patients (r = 0.597, P < 0.01); and between the gammadelta-T-cells percentage and the levels of IL-17 (r = 0.469,P < 0.01). However, no correlation was found between the Th17 cell percentage and the levels of IL-17 (r = 0.100, P > 0.05). CONCLUSION: Gammadelta-T-cells and Th17 cells may be involved in the pathogenesis of AR; gammadelta-T-cells may primarily be associated with the secretion of IL-17.

Phenotypic characterization of circulating CD4/CD8 T-lymphocytes in ß-thalassemia patients.

BACKGROUND: Infection is one of the most common causes of death in ß-thalassemia patients. This may be due in part to an underlying immunological abnormality. During the past decade, a subset of CD3+ T cells that express both CD4+CD8+ (DP) T-cells were discovered and have been described in several pathological conditions. However, phenotypic characterization of this unique T-lymphocyte subset in patients with ß-thalassemia has not yet been investigated. METHODS: Flow cytometry was used to determine the frequency of such CD4+CD8+(DP) cells in concert with frequencies of CD4+, CD8+, NKT cells and γδ-TCR T-lymphocytes in the peripheral blood of ß-thalassemia/HbE patients. The frequencies of these lymphocyte subsets were compared with those in blood samples from healthy volunteers. RESULTS: The results showed that the frequency of lymphocytes was significantly increased in splenectomized ß-thalassemia/HbE patients but the frequencies of CD3+, CD4+ and CD8+ T-lymphocytes were not significantly different among the studied groups. However, analysis of unconventional T-lymphocytes revealed a significant increase in the frequency of CD4-CD8- in splenectomized ß-thalassemia/HbE patients. The frequencies of CD4-CD8dim and CD4+CD8+ in ß-thalassemia/HbE patients were similar to the controls. Further classification of the CD4+CD8+ cells revealed that ß-thalassemia/HbE patient expressed significantly high levels of CD4brightCD8dim, with a marked increase found in non-splenectomized patients. Furthermore, significant increases in the frequency of γδ-TCR and NKT cells were also demonstrated in these splenectomized ß-thalassemia/HbE patients. CONCLUSION: Our findings show the alteration of unconventional T-lymphocyte subsets in ß-thalassemia/HbE patients, which may be responsible or may reflect the impaired immune response in ß-thalssemia disease.

Involvement of CD161+ Vδ1+ γδ T cells in systemic sclerosis: association with interstitial pneumonia.

OBJECTIVE: Interstitial pneumonia (IP) is a chronic progressive interstitial lung disease associated with high mortality and poor prognosis. However, the pathogenesis of IP remains to be elucidated. The aim of this study was to clarify the role of CD161(+) Vδ1(+) γδ T cells in SSc patients with IP. METHODS: The proportion of CD161(+) Vδ1(+) γδ T cells in peripheral blood mononuclear cells (PBMCs) and serum sialylated carbohydrate antigen (KL-6) levels were determined. GeneChip analysis was performed with CD161(-) and CD161(+) Vδ1(+) γδ T cells. Cytokine and chemokine expression from CD161(+) Vδ1(+) γδ T cells was measured and used to evaluate the effect of culture supernatant on fibroblast proliferation. RESULTS: The proportion of CD161(+) Vδ1(+) γδ T cells was significantly higher in SSc than healthy controls (HCs) and correlated negatively with serum KL-6 levels in IP-positive SSc patients. The gene and mRNA expression level of chemokine ligand 3 (CCL3) was markedly higher in CD161(+) Vδ1(+) γδ T cells than in CD161(-) Vδ1(+) γδ T cells. CD161(+) Vδ1(+) γδ T cells in IP-positive SSc patients showed higher production of CCL3 and lower production of IFN-γ than in HCs. Culture supernatant derived from IP-negative and IP-positive SSc patients promoted fibroblast proliferation, whereas that from HCs did not. CONCLUSION: The small proportion and the altered cell functions of CD161(+) Vδ1(+) γδ T cells among PBMCs in SSc patients play a role in the pathogenesis of IP. These findings suggest that CD161(+) Vδ1(+) γδ T cells may play a regulatory role in the pathogenesis of IP in SSc patients via IFN-γ production.