HIV-1感染者CD73~+CD8~+ T细胞减少与T细胞异常活化的相关性研究

目的探讨HIV-1感染者外周血CD8~+T细胞上CD73的表达特点及其与T细胞异常活化和疾病进展的关系。方法研究入选65例HIV-1感染者和27例健康对照。通过流式细胞术检测研究对象外周血CD73~+CD8~+T细胞的频率和绝对计数,并将患者CD73~+CD8~+T细胞绝对计数和频率与其CD4~+T细胞计数、HIV-1载量以及CD38~+CD8~+T细胞频率进行相关性分析。结果与健康对照相比,HIV-1感染者外周血CD73~+CD8~+T细胞绝对计数和频率均明显降低(P均0.05);HIV-1感染者外周血CD73~+CD8~+T细胞绝对计数和频率与CD4~+T细胞计数呈正相关(r=0.555,P=0.001;r=0.342,P=0.005),与CD38~+CD8~+T细胞频率呈负相关(r=-0.384,P=0.002;r=-0.387,P=0.001);HIV-1感染者CD73~+CD8~+T细胞的绝对计数与HIV-1载量呈弱负相关(r=-0.261,P=0.035)。结论 HIV-1感染者外周血CD73~+CD8~+T细胞的减少不但与患者T细胞的活化程度呈显著负相关,而且与AIDS疾病进展相关。     

Persistent numbers of tetramer+ CD8(+) T cells, but loss of interferon-gamma+ HIV-specific T cells during progression to AIDS

Although CD8(+) T cells initially suppress human immunodeficiency virus (HIV) replication, cytotoxic T-cell precursor frequencies eventually decline and fail to prevent disease progression. In a longitudinal study including 16 individuals infected with HIV-1, we studied both the number and function of HIV-specific CD8(+) T cells by comparing HLA-peptide tetramer staining and peptide-induced interferon-gamma (IFN-gamma) production. Numbers of IFN-gamma-producing T cells declined during progression to acquired immunodeficiency syndrome (AIDS), whereas the number of tetramer+ T cells in many individuals persisted at high frequencies. Loss of IFN-gamma-producing T cells correlated with declining CD4(+) T-cell counts, consistent with the need of CD4(+) T-cell help in maintaining adequate CD8(+) T-cell function. These data indicate that the loss of HIV-specific CD8(+) T-cell activity is not due to physical depletion, but is mainly due to progressively impaired function of HIV-specific CD8(+) T cells.     

Prognostic significance of tumour-infiltrating T lymphocytes and T-cell subsets in de novo diffuse large B-cell lymphoma: a multiparameter flow cytometry study

Tumour-infiltrating T lymphocytes (TIL-T) have been implicated in playing a role in controlling tumour growth. We evaluated TIL-T in 55 cases of de novo diffuse large B-cell lymphoma (DLBCL) using three- or four-colour flow cytometric immunophenotyping (FCI). The percentage of TIL-T varied from 3% to 72% of total viable cellular events (mean 32 +/- 20%). The CD4:CD8 ratio varied from 0.17 to 13 (mean 2.3 +/- 2.2). Cases with >/= 20% T cells and those with CD4:CD8 ratios > or = 2.0 showed a significantly better overall survival (P = 0.017 and P = 0.034 respectively). These findings were independent of clinical stage at diagnosis. The T-cell percentage and CD4:CD8 ratio were moderately correlated (Spearman correlation coefficient = 0.47, P = 0.001) and multivariate analysis revealed that the association of the two factors with prognosis was mutually dependent. The T cells in 23 cases were studied for CD45RO. The mean percentage of total T cells expressing CD45RO was 86 +/- 10%. There was a trend towards better survival for those patients with a higher percentage of CD45RO+ T cells (P = 0.06). These results suggest that TIL-T, particularly CD4+ T cells, may play a role in the control of DLBCL, and measurement of T-cell percentage and T-cell subsets using FCI may be useful in predicting the clinical behaviour of DLBCL.     

De novo T-cell generation in patients at different ages and stages of HIV-1 disease

We assessed de novo T-cell generation by determining T-cell receptor-rearrangement excision circles (TRECs) based on patient age and on stage of HIV-1 infection. TRECs were measured in purified CD4 and CD8 T cells of a large cohort of HIV-1-infected subjects (n = 297) with chronic infection but no previous antiretroviral treatment and of a control group of HIV-negative subjects (n = 120). HIV-1-infected subjects were stratified on the basis of CD4 T-cell counts in 3 groups, early-stage disease (more than 500 CD4 T cells), intermediate-stage disease (200-500 CD4 T cells), and late-stage disease (fewer than 200 CD4 T cells). Compared with the control group, CD8 TREC contents were severely reduced (P <.001) in HIV-1-infected subjects regardless of the stage of HIV disease. In contrast, CD4 TREC contents were significantly increased (P =.003) in HIV-1-infected subjects during early-stage disease, similar at intermediate-stage disease, and severely reduced only at late-stage disease. We show that the increase in CD4 TRECs was mostly limited to younger (younger than 45 years) patients at early-stage disease. Our results demonstrate a dichotomy between TREC contents in CD4 and CD8 T-cell populations in HIV-1 infection and indicate that thymus function in younger subjects is preserved at early and intermediate stages of HIV infection.     

Immune restoration does not invariably occur following long-term HIV-1 suppression during antiretroviral therapy. INCAS Study Group

BACKGROUND: Current antiretroviral treatment can induce significant and sustained virological and immunological responses in HIV-1-infected persons over at least the short- to mid-term. OBJECTIVES: In this study, long-term immune reconstitution was investigated during highly active antiretroviral therapy. METHODS: Patients enrolled in the INCAS study in The Netherlands were treated for 102 weeks (range 52-144 weeks) with nevirapine (NVP) + zidovudine (ZDV) (n = 9), didanosine (ddl) + ZDV (n = 10), or NVP + ddl + ZDV (n = 10). Memory and na?ve CD4+ and CD8+ T cells were measured using CD45RA and CD27 monoclonal antibodies (mAb), T-cell function was assayed by CD3 + CD28 mAb stimulation, and plasma HIV-1 RNA load was measured by ultra-direct assay (cut-off < 20 copies/ml). RESULTS: Compared to both double combination regimens the triple combination regimen resulted in the most sustained increase in CD4+ T cells (change in CD4+, + 253 x 10(6) cells/l; standard error, 79 x 10(6) cells/l) and reduction of plasma HIV-1 RNA. In nine patients (31%) (ddl + ZDV, n = 2; NVP + ddl + ZDV, n = 7) plasma HIV-1 RNA levels remained below cut-off for at least 2 years. On average, these long-term virological responders demonstrated a significantly higher increase of na?ve and memory CD4+ T cells (P = 0.01 and 0.02, respectively) as compared with patients with a virological failure, and showed improved T-cell function and normalization of the na?ve; memory CD8+ T-cell ratio. However, individual virological success or failure did not predict the degree of immunological response. T-cell patterns were independent of baseline CD4+ T-cell count, T-cell function, HIV-1 RNA load or age. Low numbers of na?ve CD4+ T cells at baseline resulted in modest long-term na?ve T-cell recovery. CONCLUSIONS: Patients with prolonged undetectable plasma HIV-1 RNA levels during antiretroviral therapy do not invariably show immune restoration. Na?ve T-cell recovery in the setting of complete viral suppression is a gradual process, similar to that reported for immune recovery in adults after chemotherapy and bone marrow transplantation.     

SDF-1alpha is a potent inducer of HIV-1-Specific CD8+ T-cell chemotaxis, but migration of CD8+ T cells is impaired at high viral loads

Multiple impairments in HIV-1-specific cytotoxic T cells (CTL) have been reported, but derangements in HIV-1-specific CD8+ T-cell chemotaxis have not been described previously. We assessed migration to SDF-1alpha (stromal cell-derived factor 1-alpha) and CX3CL1 in vitro and expression of cognate receptors, CXCR4 and CX3CR1, by flow cytometry in peripheral blood and lymph node CD8+ T cells from HIV-1-seropositive and -seronegative individuals. Compared with seronegative individuals, percentages of CXCR4+CD8+ T cells were reduced (median, 26% versus 74%, p < 0.001) and percentages of CX3CR1+CD8+ T cells were increased (median, 33% versus 15%, p = 0.03) in seropositive individuals. Robust migration of peripheral blood mononuclear cell (PBMC) CD8+ T cells to SDF-1alpha (1 alphag/ml) was observed in both HIV-1-seropositive (median chemotactic index [CI] 4.9) and -seronegative (median CI 2.8) subjects (p = 0.46). CI to SDF-1alpha was not significantly related to percentage of CXCR4+CD8+ T cells or density of CXCR4, but correlated inversely with plasma HIV-1 RNA concentration (r = -0.82, p = 0.03). Little chemotaxis was observed in response to CX3CL1 and it was unrelated to CX3CR1 expression. Lymph node CD8+ T-cell chemotaxis to SDF-1alpha and CX3CL1 in four subjects demonstrated the same patterns observed in PBMC. HIV-1-specific tetramer-staining CD8+ T cells exhibited chemotaxis of similar magnitude as PBMC CD8+ T cells in a subset of subjects. These data suggest that SDF-1alpha is a potent chemoattractant for HIV-1-specific CTL, but that impairments in migration of HIV-1-specific CTL may exist at high viral loads. Improved understanding of the determinants of CTL localization may provide insight into novel therapies to enhance delivery of CTL to sites of HIV-1 replication.     

Intracellular IFN-gamma expression by CD3+/CD8+ cell subset in B-CLL patients correlates with stage of the disease

Changes in the cytokine network may be responsible for malignant cell accumulation in B-cell chronic lymphocytic leukaemia (B-CLL). Among different cytokines of question interferon gamma (IFN-gamma) is indicated to prevent malignant cells from entering apoptosis. The aim of the study was to determine IFN-gamma production capacity of T-cell subsets and B lymphocytes in B-CLL patients in comparison with healthy individuals and during disease progression. Forty patients with newly diagnosed, untreated B-CLL and 20 healthy individuals were studied. The two- and three-colour flow cytometry techniques were used to detect intracellular cytokine expression. We detected statistically significantly higher percentage of both CD3+/CD4+/IFN-gamma+ and CD3+/CD8+/IFN-gamma+ in patients than in controls (P < 0.001 in both cases). Moreover the percentage of CD3+/CD8+/IFN-gamma+ cells correlated with stage of the disease (R = 0.39, P = 0.01) and parameters of disease progression like lymphocyte count and total tumour mass score (R = 0.33, P = 0.03 and R = 0.31, P = 0.04, respectively). By contrast, the percentage of CD19+/IFN-gamma+ cells in B-CLL group was lower than in controls (P < 0.01). These findings indicate that T-cell populations rather than malignant B cells are the source of IFN-gamma in B-CLL patients. The subset of CD3+/CD8+ cells expressing IFN-gamma seems to play a special role in the disease progression and more precise investigation should elucidate its role as a prognostic marker in B-CLL and a target for therapeutic strategies.     

The magnitude and breadth of hepatitis C virus-specific CD8+ T cells depend on absolute CD4+ T-cell count in individuals coinfected with HIV-1

CD8(+) T-cell responses are an essential antiviral host defense in persistent viral infections, and their sustained effectiveness is thought to be critically dependent on CD4(+) T-helper cells. To determine the relationship between HIV-1-induced CD4(+) T-cell depletion and hepatitis C virus (HCV)-specific CD8(+) T-cell responses during viral persistence, we studied 103 persons positive for HCV, 74 coinfected with HIV-1. CD8(+) T-cell responses to the entire HCV polyprotein were determined by using an interferon-gamma enzyme-linked immunospot (ELISpot) assay. Although HIV-1 infection by itself was not associated with a diminished HCV-specific response, HIV-1-associated CD4(+) depletion was associated with significantly lower HCV-specific CD8(+) T cells (R = 0.48, P < .0001). In contrast, declining CD4(+) counts over the same range were not associated with diminished Epstein-Barr virus (EBV)- (R = 0.19, P = .31) or HIV-1-specific (R = -0.13, P = .60) CD8(+) T-cell responses in persons infected with all viruses. These data indicate that frequencies of circulating HCV-specific CD8(+) T-cell responses are sensitive to absolute CD4(+) T-cell counts and provide a possible explanation for the accelerated HCV disease course in persons coinfected with HIV-1 and HCV.     

HIV／AIDS患者血浆病毒载量及外周血T淋巴细胞亚群的变化

目的：观察国内HIV／AIDS患者血浆病毒载量和外周血CD4^ 、CD8^ T淋巴细胞的变化，探讨这些变化的临床意义。方法：选择未经抗病毒治疗的HIV／AIDS患者124例，用bDNA法检测血浆病毒载量，并用流式细胞仪检测外周血CD4^ 、CD8^ T淋巴细胞。结果：AIDS患者的血浆病毒载量明显高于HIV感染者，血浆病毒载量与CD4^ 细胞计数呈显著负相关，但其最高峰位于CD4^ 细胞计数100／μl处，然后随着CD4^ 细胞计数的下降而减少。CD4^ T细胞计数为AIDS组＜HIV组＜正常对照组：HIV感染者的CD8^ T细胞计数显著高于正常组和AIDS组，而AIDS患者CD8^ T细胞数则随着CD4^ T细胞减少而下降。结论：血浆病毒载量随着疾病进展而显著升高，但在疾病晚期则有所降低。外周血CD4^ T细胞计数随着疾病的进展而进行性减少；CD8^ T细胞计数在感染早期显著升高，进入晚期则减少。在评价HIV感染者和AIDS患者病情时，应结合病毒载量、CD4^ 、CD8^ T细胞计数综合分析。     

Immunological comparison of HIV-1-, HIV-2- and dually-reactive women delivering in Abidjan, C?te d'Ivoire.

OBJECTIVES: To compare the basic immunological changes induced by HIV-1 and HIV-2 infection and to assess the immune status of subjects serologically reactive to both HIV-1 and HIV-2 (dually-reactive). DESIGN: Immune parameters were studied cross-sectionally in women delivering in Abidjan, C?te d'Ivoire, West Africa, where HIV-1 and HIV-2 are endemic. In this area, a significant number of sera from infected individuals are reactive to both HIV-1 and HIV-2. SUBJECTS AND METHODS: Two hundred and twenty-eight women delivering in a major maternity clinic were screened for HIV-1 and HIV-2 using an enzyme-linked immunosorbent assay. Seropositivity was confirmed by Western blot. The immune parameters studied were CD4+ and CD8+ lymphocyte subsets, immunoglobulin (Ig) serum levels, neopterin and beta 2-microglobulin (beta 2M) serum levels. RESULTS: Similar but less pronounced immune changes were present in HIV-2-reactive subjects compared with HIV-1- and dually-reactive subjects. The observed differences between the HIV-seropositive groups could not be explained by differences in age or disease stage but paralleled differences in the frequency of persistent generalized lymphadenopathy (PGL). The intermediate immune profile of HIV-2-reactives (between seronegatives and HIV-1- and dually-reactives) was most clearly reflected by the number of CD8+ lymphocytes, the CD4:CD8 ratio and the IgG serum level. Median neopterin and beta 2M levels, though significantly increased in all HIV-seropositive groups, did not differ significantly between HIV-2-, HIV-1- and dually-reactives. CONCLUSIONS: HIV-2 infection is associated with typical HIV-related immunological changes. Immunologically, dually-reactives resemble HIV-1-reactives more closely than HIV-2-reactive subjects.     

'Modeling' relationships among HIV-1 replication, immune activation and CD4+ T-cell losses using adjusted correlative analyses

OBJECTIVE: To model the relationships among HIV-1 replication, immune activation and CD4+ T-cell losses in HIV-1 infection. METHODS: Cross-sectional analysis of baseline data from the Viral Activation by Transfusion Study. Comparisons of unadjusted and adjusted correlative analyses to establish models for mechanisms of cell loss in AIDS. RESULTS: Using these analyses, significant correlations were found among plasma levels of tumor necrosis factor alpha (TNFalpha) and its type two receptor (TNFrII), interleukin-6 (IL-6), beta2-microglobulin, expression of CD38 and HLA-DR on CD8+ T lymphocytes and plasma levels of HIV-1 RNA. When correlations among these indices were adjusted for possible intermediary correlations, the relationship between HIV-1 RNA levels and all plasma markers of immune activation could be accounted for by the correlation between plasma HIV-1 RNA and plasma TNFrII levels. In addition, the negative correlations that both HIV-1 RNA levels and TNFrII levels had with CD4+ T-cell counts were partially accounted for by the correlations of HIV-1 RNA and TNFrII with CD38 expression on CD8+ T cells. In persons with advanced disease (CD4+ T cells < 50 x 10(6)/l) IL-6 levels were inversely correlated with CD4+ T-cell counts. CONCLUSIONS: This analysis is consistent with a model wherein HIV-1 replication induces TNFalpha expression that induces multiple other indices of immune activation. In this model, HIV-1 replication and TNFalpha expression induce CD4+ T-cell losses at least in part through mechanisms reflected in heightened CD38 expression.     

Proliferation of double-negative (CD4−CD8−) T cells bearing T-cell receptor-αβ in a haemophiliac with human immunodeficiency virus type 1 infection and factor VIII inhibitor: functional properties of double-negative T-cell receptor-αβ+ T cells

We present a patient with haemophilia A showing human immunodeficiency virus type 1 (HIV-1) infection and factor VIII inhibitor in whom a novel T-cell subpopulation, double-negative (CD4-CD8-) T cells bearing T-cell receptor (TCR)-alpha beta, proliferated polyclonally in the peripheral blood. An interleukin-2-dependent T-cell line with a CD4-CD8-TCR-alpha beta+ phenotype was established from the peripheral blood lymphocytes of the patient, and its biological functions were studied. It was found that the CD4-CD8-TCR-alpha beta+ T cells possessed both HLA-unrestricted cytotoxicity and helper function for immunoglobulin production by B cells. In addition, these T cells were found to produce interferon-gamma and interleukin-2 following activation via CD3-TCR complexes. These data demonstrating the multifunction of these newly defined CD4-CD8-TCR-alpha beta+ T cells thus suggest that these cells play an important role in protection against HIV infection. The mechanism of production of factor VIII inhibitor in the present case is also discussed focusing on the CD4-CD8-TCR-alpha beta+ T cells.     

Immunological changes in primary HIV-1 infection

Homosexual men with symptomatic primary HIV-1 infection displayed a pronounced lymphopaenia with significantly depressed numbers of CD3+, CD4+ and CD8+ cells and B cells during the first week of illness. Subsequently, the CD8+ cell counts rose in parallel with numbers of CD3+ cells, atypical lymphocytes and activated (CD38+ and HLA-Dr+) cells to attain maximal levels about a month following onset of illness. In contrast CD4+ and B cell numbers remained low for an extended period of time. Early signs of a host response included a transient appearance of interferon-alpha in the blood and raised levels of neopterin and beta 2-microglobulin (beta 2-M). Neither CD4+/CD8+ cell ratio nor beta 2-M resumed completely normal values during a follow-up period of 2 years. These findings shed some light on pathogenetic events during early HIV-1 infection and suggest that the infection, following the acute symptomatic stage, usually enters a stage of chronic active rather than latent infection.     

Low percentages of circulating CD8(+)/CD45RA(+) human T lymphocytes expressing beta7 integrin correlate with the occurrence of intestinal acute graft-versus-host disease after allogeneic hematopoietic stem cell transplantation

OBJECTIVE: Effector phase of acute graft-versus-host disease (a-GVHD) is mainly mediated by donor-derived, anti-host cytotoxic T cells. T-cell homing into gut-associated lymphoid tissues is ascribed to the alpha4beta7 integrin. We reasoned that development of intestinal a-GVHD might be triggered by recruitment in the intestinal mucosa of circulating, alloreactive, alpha4beta7(+) donor T cells. Therefore, we evaluated the correlation existing between circulating beta7(+) T-lymphocyte subsets early after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and occurrence of a-GVHD. PATIENTS AND METHODS: Surface expression of beta7 integrin on T cells was evaluated by means of direct immunofluorescence, in three-color analysis. Sixty-five patients given allo-HSCT were evaluated: 13 of them experienced intestinal a-GVHD, 14 developed a-GVHD without intestinal involvement, and 38 did not develop a-GVHD. Patients were studied early after initial signs of hematologic reconstitution and before occurrence of a-GVHD. RESULTS: We found a significantly higher absolute number of CD8(+) and a significantly lower percentage of CD8(+)CD45RA(+)beta7(+) T cells in patients with intestinal a-GVHD than in patients with a-GVHD without intestinal involvement (p = 0.003 and p = 0.003, respectively) or not experiencing a-GVHD (p = 0.02 and p = 0.002, respectively). In particular, we found that intestinal a-GVHD occurred in over 70% of patients showing an absolute number of CD8(+) T cells > or = 60 x 10(6)/L and a percentage of circulating CD8(+)CD45RA(+)beta7(+) T cells < 35%. CONCLUSION: Measuring the absolute number of CD8(+) T cells and percentage of CD8(+)CD45RA(+)beta7(+) T cells at time of hematologic reconstitution may help identify patients at risk of developing intestinal a-GVHD who could benefit from strategies aimed at hampering alloreactive T-cell homing to intestinal mucosa.     

T-cell receptor variable region gene usage by CD4+ and CD8+ T cells in bronchoalveolar lavage fluid and peripheral blood of sarcoidosis patients.

Sarcoidosis is a chronic noncaseating granulomatous disease of unknown etiology. An accumulation of CD4+ T cells in the alveolar space of the lungs is a characteristic feature of the disease. We have in this study analyzed T-cell receptor (TCR) variable region (V) gene usage by CD4+ and CD8+ lung and peripheral blood T cells of 29 sarcoidosis patients and 15 control subjects. In the patient group, we found a 100% positive correlation between TCR V alpha 2.3+ CD4+ lung T-cell expansions and the expression of the HLA-DR3(17),DQ2 haplotype. The remaining TCR V alpha/V beta gene products analyzed in this study--V alpha 12, V beta 2, V beta 3, V beta 5.1, V beta 5.2/5.3, V beta 5.3, V beta 6.7, V beta 8.1, and V beta 12--were in general normally expressed by CD4+ T cells, although some of them were used to a significantly higher or lower degree by lung T cells compared to peripheral blood T cells. We also performed repeated TCR V gene analyses on some HLA-DR3+ patients and found an association between the ratio bronchoalveolar lavage fluid/peripheral blood V alpha 2.3+ CD4+ T cells and clinical signs of disease activity. Finally, when analyzing TCR V gene usage by CD8+ bronchoalveolar lavage fluid and peripheral blood T cells, a normal V alpha 2.3 usage was found in all cases, but lung-restricted T-cell expansions using other TCR V gene segment products were identified.     

人类免疫缺陷病毒感染者T淋巴细胞亚群增殖、活化与疾病进展的相关性

目的 探讨慢性未治疗HIV/AIDS患者T淋巴细胞增殖活化与疾病进展的相关性.方法 以16例健康人及49例慢性未治疗的HIV/AIDS患者为研究对象,HIV/AIDS患者根据CD4+T淋巴细胞计数分为CD4+T淋巴细胞<200×106/L组、(200～350)X106/L组、>350X106/L组.分离患者外周血单个核细胞(PBMC),Ki-67标记细胞增殖,CD38标记细胞活化,流式细胞仪检测各项指标.数据采用单因素方差分析.结果CD4+T淋巴细胞<200×106/L组Ki-67+CD4+T 淋巴细胞比例为7.92%±4.37%,高于健康对照组的0.39%±0.24%、(200～350)×106/L组的2.61%±2.12%和>350X 106/L组的2.65%±2.13%,差异均有统计学意义(F=21.961,P<0.01);CD4+T淋巴细胞<200X106/L组Ki-67+CD8+T淋巴细胞比例为2.87%±1.13%,高于健康对照组的0.15%±0.90%、(200～350)×106/L组的1.40%±1.17%和>350×106/L组的1.22%±0.80%,差异均有统计学意义(F=19.203,P<0.01).且Ki-67+CD4+和Ki-67+CD8+T淋巴细胞比例与CD4+T淋巴细胞计数呈负相关(r=-0.654,r=-0.539;均P<0.01),而与病毒载量无关.CD4+T淋巴细胞<200×106/L组CD38+CD4+、CD38+CD8+T淋巴细胞比例分别为44.14%±20.65%和50.64%±21.08%,健康对照组为10.22%±3.98%和6.46%±3.99%,(200～350)×106/L组为16.03%±10.20%和19.33%±13.43%,>350×106/L组为13.69%±10.70%和16.98%±15.75%(F=14.333,F=15.412;均P<0.01),且CD4+和CD8+T淋巴细胞Ki-67的表达程度与CD38呈正相关(r=0.527,r=0.391;均P=0.002).结论 随着慢性HIV/AIDs疾病的进展,T淋巴细胞的增殖与活化均显著增高,T淋巴细胞活化可能是免疫持续激活的结果.     

正常T细胞分泌激活因子基因多态性与HIV-1感染者病毒载量、CD+4细胞计数和CD+4/CD+8比值的关系

目的分析正常T细胞分泌激活因子(RANTES)启动子和内含子等位基因,对艾滋病病毒1型(HIV-1)感染者外周血CD+4细胞计数、CD+4/CD+8比值和病毒载量的关系,以期探讨RANTES单核苷酸多态性(SNP)和艾滋病(AIDS)发病的关系.方法用流式细胞仪和real time法对40例汉族HIV-1感染者测定外周血CD+4、CD+8细胞计数和病毒载量,应用PCR-RFLP法进行基因分型.结果对RANTES-403、-28和In1.1三个位点等位基因与外周血CD+4T淋巴细胞计数、CD+4/CD+8+比值和病毒载量的关系的分析表明,具有RANTESIn1.1 C/C和T/C基因型的感染者,与较高的病毒载量、较低的C+4T细胞计数和C+4/CD+8比值有关.In1.1 T/T与T/C、C/C基因型的log10病毒载量的差异有非常显著的统计学意义(P＜0.01),但是不同基因型之间CD+4T淋巴细胞计数和CD+4/CD+8细胞比值则无显著性差异.log10病毒载量和CD+4T淋巴细胞计数(r=-0.447,P＜0.01)、CD+4/CD+8比值(r=-0.369,P＜0.05)有显著的负相关关系.结论所研究人群中,具有RANTES In1.1C的基因型者,与较高的病毒载量、较低的CD+4T细胞计数和CD+4/CD8+比值有关,它们是反映AIDS进程的主要指标,可能加速AIDS发病进程;而RANTES-403和-28等位基因的影响则处于相对次要的作用.     

Increased levels of activated subsets of CD4 T cells add to the prognostic value of low CD4 T cell counts in a cohort of HIV-infected drug users

OBJECTIVE: To identify subsets of CD4 T lymphocytes that can predict the development of AIDS and to assess whether increased levels of these cellular markers could provide additional independent prognostic information to the CD4 T cell count and plasma HIV-1-RNA levels. DESIGN AND METHODS: In a prospective study, a cohort of 85 HIV-positive intravenous drug users [clinical categories of the CDC classification A (n = 48) and B (n = 37)] were followed for a period of 37+/-13 months. Memory and activated CD4 and CD8 T cells were quantitated by three-colour flow cytometry at baseline and expressed as a percentage of total CD4 and CD8 lymphocytes. Clinical evaluations were performed at 6 month intervals. The relationships between these lymphocyte subsets and progression to AIDS were studied using Kaplan-Meier plots and proportional hazards regression models. RESULTS: After adjustment for the level of CD4 T cells and plasma HIV-1-RNA levels, the elevation in the subset CD4+CD38+DR+ was the marker within the functionally distinct subsets of CD4 T lymphocytes with additional prognostic value in bivariate Cox regression models. In multivariate models, increased percentages of CD4+CD38+DR+ T cells provided the strongest independent prognostic information for progression to AIDS (relative hazard, 1.07; P < 0.0001). CONCLUSION: Our results suggest that high levels of CD4+CD38+HLA-DR+ T cells reflect the increasing degree of CD4 T cell activation during the progression of HIV infection, and could be used together with the CD4 T cell and HIV-RNA levels to evaluate more accurately the progressive cellular immune impairment associated with the risk of progression to AIDS.     

Relationship of frequency of CD4+CD25+Foxp3+ regulatory T cells with disease progression in antiretroviral-naive HIV-1 infected Chinese

Forty-five antiretroviral-naive HIV-1 infected patients and 14 healthy controls in North China were enrolled in this study. The frequency of CD4+CD25+Foxp3+ regulatory T cells (Tregs) and levels of expression of CD95, HLA-DR and CD38 in T cells were detected by flow cytometry. We found that the frequency of Tregs was higher in AIDS patients than in asymptomatic HIV-1 infected patients (P=0.004). The frequency of Tregs was significantly correlated with absolute CD4 count, viral load, CD4+CD95+ T cells and CD8+CD95+ T cells (P<0.05). The relationship between the frequency of Tregs and immune activation was not found in HIV-infected patients. We concluded that the frequency of Tregs in HIV-infected Chinese patients was significantly correlated with disease progression.     

Expansions of CD8+CD28- and CD8+TcRVbeta5.2+ T cells in peripheral blood of heavy alcohol drinkers

BACKGROUND: Despite heavy alcohol consumption, only a low percentage of heavy drinkers develop liver disease. Imbalances in T-cell subsets and iron metabolism parameters are common findings in heavy drinkers, yet the possible role played by discrete T-lymphocyte subsets under heavy alcohol consumption remains unclear. METHODS: To gain new insights into the possible role played by T lymphocytes during alcohol consumption, characterization of CD28 expression and TcR repertoire in peripheral blood CD4+ and CD8+ T cells by two and three-color flow cytometry was performed. A group of heavy alcohol drinkers (AHD, n = 71) and a group of age-matched controls (n = 81), both HLA-phenotyped and HFE-genotyped, constituted the groups under study. RESULTS: Marked expansions of CD28- T cells within the CD8+ but not the CD4+ T-cell pool were observed in AHD compared with controls. These CD8+CD28- expansions were paralleled by expansions of CD8+ T cells bearing specific TcR Valpha/beta chains, namely VP5.2. Moreover, AHD, but not controls, carrying the H63D mutation in the HFE gene showed significantly higher percentages of CD28- T cells within the CD8+ T-cell pool than AHD carrying the normal HFE gene. Finally, high numbers of CD8+CD28- T cells in AHD were associated with lower levels of the liver-related enzymes ALT and GGT. CONCLUSIONS: This study showed that under active ethanol consumption, expansions of discrete CD8+ T-cell subsets occur within the CD8+ T-cell pool, that molecules of the MHC-class I locus seem to influence the extent of the expansions, and that high numbers of CD8+CD28- T cells are associated with low levels of liver enzymes in AHD.