Persistent expansions of CD4+ CD8+ peripheral blood T cells

CD4+ CD8+ cells are present during T cell differentiation in the thymus. Less than 2% of normal T cells that coexpress CD4 and CD8 also are released in the circulation and are present in the peripheral blood. In this study, nine individuals are described that manifested persistent expansions (11% to 43%) of circulating CD4+ CD8+ T cells that in three cases had large granular lymphocyte (LGL) morphology in the absence of either lymphocytosis or overt lymphoproliferative disorders. Southern blot hybridization of enriched CD4+ CD8+ cells with T-cell receptor beta (TCR beta) and TCR gamma probes showed that most cases had the 12-kb Eco RI germinal band deleted or of decreased intensity. In several individuals new TCR beta-specific bands of different intensity and distinct from case to case suggested either monoclonal or oligoclonal and polyclonal expansions. Immunophenotypic analysis showed that in 7 out of 9 cases the CD4+ CD8+ T cells presented with CD8 dim expression. Furthermore, all the CD4+ CD8+ cells did not express many of the known activation antigens (low or absent CD25, CD38, CD71, HLA-DR), whereas they expressed high levels of CD2, CD29, CD56, and CD57. In addition, the CD4+ CD8+ cells of 5 out of 9 subjects coexpressed CD45RA and CD45RO suggesting that these cells might be "frozen" in an intermediate state between naive and memory T cells. In conclusion, the present CD4+ CD8+ cases fall within a larger spectrum of disorders ranging from apparently normal to reactive or proliferative situations and encompassing cells with LGL morphology or LGL-associated antigens expression either in the presence or in the absence of absolute lymphocytosis that deserve careful follow-up investigations.     

Simian immunodeficiency virus infection of CD4+CD8+ T cells in a macaque with an unusually high peripheral CD4+CD8+ T lymphocyte count

We assessed the possible role in vivo CD4(+) CD8(+) T cells as a viral reservoir for simian immunodeficiency virus (SIV), in a macaque with 50% CD4(+) CD8(+) T cells in peripheral blood. During primary infection (day 14) of this rhesus macaque with the pathogenic SIVmac251 strain, proviruses were detected at similar frequencies in CD4(+) CD8(+) T cells (1/10) and CD4(+) T cells (1/10) and at a lower frequency in CD8(+) T cells (1/800). On day 235, no viral DNA was detected in CD8(+) cells, despite the persistent high viral load, indicating that CD8(+) cells do not constitute a reservoir during the chronic phase of SIV infection. Infection induced early lymphopenia of CD4(+), CD4(+) CD8(+), and CD8(+) cells; only the CD8(+) cell population returned to initial levels and expanded further. We found that CD4(+) CD8(+) T cells expressed the costimulatory CD28 molecule less and were more prone to die in vitro after phytohemagglutinin/interleukin 2 stimulation than were CD4(+) T cells. Taken together, massive death of CD4(+) CD8(+) T cells during acute stages of SIV infection may explain why CD8(+) T cells did not represent a major reservoir for SIV at the onset of infection.     

慢性乙型肝炎患者外周血CD8+CD28+T淋巴细胞百分比的变化及其临床意义探讨

目的 探讨不同病程阶段的慢性乙型肝炎患者外周血CD8⁺CD28⁺T淋巴细胞百分比的变化,以及CD8⁺CD28⁺T淋巴细胞百分比变化与血清HBsAg水平的关系。方法 2018年4月~2018年8月我院诊治的慢性乙型肝炎患者88例,其中免疫耐受期20例,免疫清除期28例,非活动期20例,再活动期20例,另选择健康人20例。使用流式细胞术检测外周血CD8⁺CD28⁺T淋巴细胞百分比。结果 健康人与免疫耐受期患者外周血CD8⁺CD28⁺T淋巴细胞百分比分别为（26.1±3.5）%和（26.3±3.4）%,差异无统计学意义（P>0.05）;免疫清除期患者CD8⁺CD28⁺T淋巴细胞百分比为（40.1±4.7）%,显著高于健康人（P<0.05）;非活动期和再活动期患者外周血CD8⁺CD28⁺T淋巴细胞百分比分别为（20.3±2.2）%和（26.1±2.2）%,显著低于健康人（P<0.05）;外周血HBsAg低、中、高三组人群外周血CD8⁺CD28⁺T淋巴细胞百分比分别为（24.0±7.5）%、（28.4±8.9）%和（33.2±8.5）%,各组间差异有统计学意义（P<0.05）。结论 不同病程阶段的慢性乙型肝炎患者外周血CD8⁺CD28⁺T淋巴细胞百分比存在明显差异,可能与病毒长期刺激机体免疫系统,导致免疫系统功能失调有关,而这种失调可能参与了慢性乙型肝炎的发病过程。     

Expansion of TcRalphabeta+CD3+CD4-CD8- (CD4/CD8 double-negative) T lymphocytes in a case of staphylococcal toxic shock syndrome

A 55-year-old woman presented with staphylococcal toxic shock syndrome (TSS). During the course of the disease a significant lymphocytosis appeared, and a high number of TcRalphabeta+CD3+CD4-CD8- (double-negative, DN) lymphocytes was observed both in bone marrow and in peripheral blood samples. Correction of the altered lymphocyte immunophenotype was observed only 6 weeks after recovery from TSS. The immunophenotype of circulating and bone marrow lymphocytes was also studied during a phase of an aspecific febrile episode observed 2 months after recovery, but no subset of DN lymphocytes was found. A small subset of DN lymphocytes can be found in normal bone marrow, liver, thymus, and skin. These cells show peculiar immune regulatory properties and can increase in certain autoimmune diseases. Our findings may represent a specific effect of lymphocyte stimulation by the staphylococcal exotoxin, which is the effector agent of TSS.     

Evaluation of a quantitative determination of CD4 and CD8 molecules as an alternative to CD4+ and CD8+ T lymphocyte counts in Africans

In the developed word, monitoring HIV-infected patients is routinely determined by CD4+ T lymphocyte absolute counts. The reference procedure, flow cytometry, is expensive, requires sophisticated instrumentation and operators with specific training. Due to these limitations, CD4 counting is often unavailable in developing countries. The Capcellia assay is an enzyme-linked immunoassay for quantitative determination of CD4 and CD8 molecules. We evaluated this method in West Africa on blood samples collected from 39 HIV-uninfected and 44 HIV-infected adult subjects. CD4 concentration ranges were determined according to the clinical stages of the disease. We then studied the relationship between the two methods in the HIV-infected patients. The Spearman's rank correlation was 0.61 (95% confidence interval: 0.38-0.76, P < 0.0001). Nevertheless, determination of limits of agreement revealed discrepancies between the two methods, especially for CD4 counts > 0.4 x 10(9)/l, which are discussed. We conclude that the Capcellia assay is a convenient means to determine the immunodepression level where flow cytometric instrumentation is unavailable, and can be complementary to CD4 T lymphocyte enumeration.     

Age-dependent accumulation of monoclonal CD4+CD8+ double positive T lymphocytes in the peripheral blood of the elderly

Multicolour flow cytometric analysis enabled the identification of monoclonal B-cell lymphocytosis (MBL), frequently resembling chronic lymphocytic leukaemia, at a rather high frequency in peripheral blood (PB) samples from an elderly population. PB T lymphocytes from 103 otherwise healthy subjects >65 years of age and 51 younger donors (<65 years) were analysed. Besides CD4(+) and CD8(+) single positive (SP) cells, CD4(+)CD8(+) double positive (DP) mature T lymphocytes were present in both series and could be further distinguished into CD4(high)CD8(low) and CD4(low)CD8(high) subsets. An age-dependent increase of both DP T-cell subsets was observed, while SP T cells remained stable throughout life. Flow cytometry and polymerase chain reaction analysis of the TRBV expression profiles showed the presence of a TRBV restriction within CD4(+)CD8(+) DP cells in more than half (53/103; 55.3%) of the individuals >65 years of age, regardless the actual number of DP T cells observed. Clonal expansions were more prominent within the CD4(high)CD8(low) subset, accounting for most circulating DP clones (47/103; 45.6%). A few cases showed more than one (up to three) monoclonal expansion. Clonal CD4(low)CD8(high) DP T-lymphocyte expansions were detected in only 10/103 samples (9.7%) and showed a close phenotypic similarity to the rare T-cell large granular lymphocyte leukaemias. The similarities between DP clones and MBL in the elderly may help to better understand the mechanisms of immunosenescence and their relationships with the development of lymphoproliferative disorders.     

Early rheumatoid arthritis is associated with a deficit in the CD4+CD25high regulatory T cell population in peripheral blood

OBJECTIVE: Our aim was to test the hypothesis that there is a deficit in the CD4+CD25high regulatory T-cell population in early rheumatoid arthritis (RA), either in size or functional activity. METHODS: Peripheral blood mononuclear cells were examined from subjects with early active RA who had received no previous disease-modifying therapy (n = 43), from individuals with self-limiting reactive arthritis (n = 14), from subjects with stable, well-controlled RA (n = 82) and from healthy controls (n = 72). The frequencies of CD4+CD25high T-cells were quantified using flow cytometry, and function was assessed by the ability to suppress proliferation of CD4+CD25- T-cells. Paired blood and synovial fluid was analysed from a small number of RA and reactive arthritis patients. RESULTS: There was a smaller proportion of CD4+CD25high T-cells in the peripheral blood of early active RA patients (mean 4.25%) than in patients with reactive arthritis or in controls (mean 5.90 and 5.30%, respectively, P = 0.001 in each case). Frequencies in stable, well-controlled RA (mean 4.63%) were not significantly different from early active RA or controls. There were no differences in suppressor function between groups. Higher frequencies of CD4+CD25high T-cells were found in synovial fluid than blood in both RA and reactive arthritis. CONCLUSIONS: These data demonstrate a smaller CD4+CD25high regulatory T-cell population in peripheral blood of individuals with early active RA prior to disease-modifying treatment. This may be a contributory factor in the susceptibility to RA and suggests novel approaches to therapy.     

儿童和青少年自身免疫性肝炎患者外周血淋巴细胞亚群变化及其临床意义探讨

目的 研究儿童和青少年AIH患者外周血淋巴细胞亚群的变化及其临床意义。 方法 2015年6月～2019年1月我院收治的儿童和青少年AIH患者42例和健康儿童和青少年50例,使用流式细胞仪检测外周血单个核细胞表面标志物。结果 AIH患者外周血CD4⁺T细胞百分比为53.1(42.5,57.8)%,显著高于健康人,而CD14⁺T细胞百分比为62.2(40.1,76.8)%,显著低于健康人,而两组外周血CD8⁺T细胞百分比无显著性差异【25.9(12.5,32.4)%对18.7(12.8,28.5)%,P>0.05);AIH患者外周血CD4⁺T淋巴细胞表面CD45RA、CD45RO、CCR3和CD28表达百分比分别为26.1(15.2,32.8)%、19.2(13.5,27.3)%、15.4(2.1,53.8)%和51.2(34.4,56.9)%,均显著高于健康人;AIH患者外周血CD8⁺T淋巴细胞表面CD45RA、CCR3和CD25表达百分比分别为18.0(14.1,26.8)%、1.2(0.5,3.2)%和0.6(0.3,7.8)%,显著高于健康人【分别为13.6(8.2,18.3)%、0.5(0.3,0.6)%和0.3(0.2,0.5)%, P<0.05],而外周血CD8⁺T淋巴细胞表面CD45RO表达百分比为2.7(2.3,4.8)%,显著低于健康人;AIH患者外周血CD14⁺T淋巴细胞表面CD45R0表达百分比为 34.7(16.3,57.8)%,显著低于健康人。结论 外周血CD4⁺、CD8⁺和CD14⁺T 细胞比例失衡及其细胞表面分子表达异常与AIH患者发病或病情进展密切相关,值得进一步研究。     

感染鸭乙型肝炎病毒鸭外周血CD4~+和CD8~+T淋巴细胞水平变化

目的了解实验感染鸭乙型肝炎I型病毒(DHBV)的实验鸭外周血CD4+T和CD8+T淋巴细胞数变化及意义。方法采用经外周静脉注射含DHBV血清制备感染鸭,应用流式细胞仪检测感染DHBV实验鸭外周血CD4+T和CD8+T淋巴细胞数。结果在感染DHBV 7日后,实验鸭血清HBs Ag、鸭HBe Ag和抗-鸭HBc均阳性,说明感染成功,感染动物肝功能损害明显,血清ALT、AST水平急剧升高,与健康对照组比,差异显著(P0.01);感染动物外周血CD4+T细胞和CD8+T细胞分别为(38.41±9.59)%和(23.80±6.44)%,均显著高于对照组[分别为(23.06±12.30)%和(17.65±10.83)%,P0.01]。结论当HBV侵入机体时就会激发细胞免疫反应,大量的CD4+T和CD8+T细胞被释放入血,参与病毒清除和肝损伤过程。     

Reference values for peripheral blood lymphocyte phenotypes applicable to the healthy adult population in Switzerland

OBJECTIVES: Use of domestic reference values is known to improve the accuracy of flow cytometric analysis by integrating local variation due to race, gender, and age. In the absence of previously published estimates, we now report establishment of reference values for a wide range of peripheral blood lymphocyte phenotypes applicable to the healthy adult population in Switzerland and other regions with similar demographic characteristics. METHODS: A representative sample population was recruited from among well characterized local blood donors (n = 70) and quantitative multiparametric flow cytometry used to estimate absolute and proportional values for a range of T-, B-, and NK-cell subsets, including those associated with activation and maturity. Distribution-free methods were then applied to generate 95% reference values and to estimate the significance of gender and age-related differences. RESULTS: Reference values were obtained for the absolute and proportional levels of total CD3(+) T cells (536-1787 cells/microL, 54.90-84.03%), helper CD4(+) T cells (309-1139 cells/microL, 32.53-62.88%), cytotoxic CD8(+) T cells (137-823 cells/microL, 11.55-38.60%), activated CD3(+) T cells expressing CD25 (7-94 cells/microL, 0.50-5.95%), CD38 (102-554 cells/microL, 5.98-26.80%), HLA-DR (18-186 cells/microL, 1.25-9.68%) or CD38/HLA-DR (4-52 cells/microL, 0.30-2.30%), activated CD4(+) T cells expressing CD25 (7-52 cells/microL, 0.33-2.80%), CD38 (69-547 cells/microL, 6.13-32.20%), HLA-DR (11-55 cells/microL, 0.80-4.43%) or CD38/HLA-DR (4-22 cells/microL, 0.30-1.35%), activated CD8(+) T cells expressing CD25 (0-12 cells/microL, 0.00-0.69%), CD38 (13-124 cells/microL, 0.93-7.03%), HLA-DR (6-108 cells/microL, 0.33-6.38%) or CD38/HLA-DR (2-47 cells/microL, 0.13-2.68%), naive CD4(+) T cells expressing CD45RA(+)/CD62L(+) (84-761 cells/microL, 9.48-41.88%), naive CD8(+) T cells expressing CD45RA(+)/CD62L(+) (42-360 cells/microL, 3.68-19.23%), memory CD4(+) T cells expressing CD45RO(+) (247-807 cells/microL, 16.50-42.15%), memory CD8(+) T cells expressing CD45RO(+) (72-377 cells/microL, 3.78-22.80%), B-cells expressing CD19 (72-460 cells/microL, 4.70-19.13%) or CD20 (66-529 cells/microL, 4.63-21.00%), total CD3(-)/(CD16(+)/CD56(+)) NK-cells (77-427 cells/microL, 5.35-30.93%), and activated NK-cells expressing CD25 (0-10 cells/microL, 0-0.50%) or HLA-DR (3-99 cells/microL, 0.20-7.28%). CONCLUSION: It is anticipated that availability of localized reference values for an extended range of peripheral blood lymphocyte phenotypes should supplement previously published reference values and enhance the utility of flow cytometric analysis undertaken in Switzerland.     

乙型肝炎病毒感染者外周血T淋巴细胞CD127的表达及其意义

D127是IL-7受体α链,在维持T淋巴细胞(简称T细胞)内环境稳态过程中发挥着重要作用.在T细胞缺乏的条件下,CD127信号可以不依赖TCR刺激T细胞增殖,促进T细胞数量的恢复.其通过抗细胞凋亡作用保证T细胞的存活,恢复外周T细胞数量,促进外周T细胞的重构,维持T细胞内环境稳态[1].     

Expansion of natural killer cell receptor (CD94/NKG2A)-expressing cytolytic CD8 T cells and CD4+CD25+ regulatory T cells from the same cord blood unit

OBJECTIVE: Cord blood contains a significant number of precursor cells that differentiate to cytotoxic effector cells and immunoregulatory cells. We tried to expand inhibitory natural killer cell receptor CD94-expressing CD8 T cells with cytolytic activity and CD4(+)CD25(+) regulatory T cells from the same cord cell unit. METHODS: Cytotoxic CD94-expressing CD8 T cells were expanded from CD4-depleted cord blood using an immobilized anti-CD3 monoclonal antibody and a cytokine and also CD4(+)CD25(+) regulatory T cells were expanded from a CD4-enriched fraction derived from the same cord blood unit using anti-CD3/CD28 monoclonal antibody-coated Dynabeads and cytokines. RESULTS: We were able to obtain a more than 1000-fold expansion of CD94-expressing CD8 T cells and a more than 50-fold expansion of CD4(+)CD25(+) cells from the same cord blood unit. These expanded CD4(+)CD25(+) cells expressed FoxP3 mRNA at a level about 100-fold higher than that in isolated CD25(-) cells and could suppress allogeneic mixed lymphocyte culture by >80% (effector cells: CD4(+)CD25(+) cells = 2:1). Cytolytic activities of purified CD94-expressing cells detected by a 4-hour (51)Cr release assay against K562 were >60%. Coculture of CD94-expressing cells with expanded CD4(+)CD25(+) cells did not have any effect on cytolytic activities of purified CD94-expressing cells against K562 cells. CONCLUSION: These expanded cytolytic CD94-expressing CD8 cells might be able to induce a graft-vs-leukemia effect without enhancing graft-vs-host disease, and CD4(+)CD25(+) cells might be able to suppress allogeneic responses, including graft-vs-host disease and graft rejection after cord blood transplantation.     

CD4 alphabeta T lymphocytes express high levels of the T lymphocyte antigen CTLA-4 (CD152) in acute malaria

The role of T lymphocytes in human acute malaria remains under debate. The kinetics of T cell activation in acute malaria were investigated, with emphasis on CTLA-4 (CD152). In patients with malaria, CTLA-4 expression by CD4 alphabeta T lymphocytes was highly increased. After initiation of antiplasmodial treatment, it returned to control values within a few days. gammadelta T cells, which also are implicated in the pathogenesis of human malaria, did not express CTLA-4. The level of CTLA-4 expression at the time of hospital admission was correlated positively with other markers of disease severity-the peak of the parasitemia and the peak of serum neopterin levels. These results show that CTLA-4 is a sensitive and dynamic marker for T lymphocyte activation. Its strong increase in acute malaria argues for the involvement of T cells in the human immune response to plasmodia.     

Role of 4-1BB (CD137) in the functional activation of cord blood CD28(-)CD8(+) T cells

The CD28(-) subset of CD8(+) T cells is associated with cytotoxic T lymphocyte (CTL) effector function. We investigated a potential role for 4-1BB, a costimulatory molecule structurally related to members of the tumor necrosis factor (TNF) receptor family, in the generation and functional activation of CD28(-) CTLs by using human cord blood (CB) cells composed exclusively of naive CD8(+) T cells with few or no CD28(-) CTLs. The 4-1BB was induced preferentially on the CB CD28(-)CD8(+) T cells when CD28 down-regulation was induced by interleukin 15 (IL-15) and IL-12 stimulation. Anti-4-1BB costimulation induced dramatic phenotypic changes in the CD28(-) CTLs, including restoration of CD28 expression as well as that of memory markers such as CD45RO and CC chemokine receptor 6 (CCR6). Anti-4-1BB costimulation also promoted long-term survival of CD28(-) CTLs, which were sensitive to activation-induced cell death upon anti-CD3 stimulation. The memory-type CD28(+) CTLs induced by anti-4-1BB costimulation acquired a greatly enhanced content of granzyme B, a cytolytic mediator, and enhanced cytotoxic activity as compared with CD28(-) CTLs. Strong cytotoxicity of memory-type CTLs to a 4-1BB ligand-expressing Epstein-Barr virus (EBV)-transformed B-cell line was almost completely abrogated by 4-1BB-Fc, a soluble form of 4-1BB, suggesting involvement of 4-1BB in cytolytic processes. Taken all together, our results suggest that 4-1BB plays a role in the differentiation of effector memory CTLs.     

Cytochemistry of human T lymphocyte subpopulations in peripheral blood

With sequential investigation of immunological and cytochemical markers on single cells, T lymphocyte subsets defined by monoclonal antibodies were examined in the peripheral blood of healthy adults. Leu-3a+ T cells (helper/inducer) were 80.0 +/- 6.6% dot positive with unspecific acid alpha-naphthyl acetate esterase (ANAE) and 52.2 +/- 15.8% dot positive with diaminopeptidase IV (DAP IV) staining, as compared to 52.6 +/- 7.6% ANAE and 29.1 +/- 10.9% DAP IV dot positivity in Leu-2a+ T cells (suppressor/cytotoxic). Although these differences were significant (P less than 0.001 and P = 0.002, respectively), the rather high % of dot positivity in Leu-2a+ cells precludes ANAE or DAP IV staining as a simple method for the determination of T lymphocyte subsets. In acid phosphatase staining, no significant difference in focal positivity between Leu3a+ and Leu-2a+ T cell subpopulations was detected (63.3 +/- 10.9% and 52.3 +/- 10.0%, respectively; P greater than 0.1).     

氨茶碱对健康人外周血T细胞及CD4~+亚群凋亡的影响

目的观察氨茶碱对分离培养的健康人外周血T细胞及CD4+亚群凋亡的影响。方法密度梯度离心法及尼龙棉柱法分离健康成年人外周血T细胞,及CD8阴性选择磁性分离健康成年人外周血CD4+T细胞。分两部分进行:①外周血T细胞分对照组、氨茶碱组(0.14～18μg/ml),培养72h后用流式细胞术检测凋亡率变化;②CD4+T细胞分对照组、小剂量氨茶碱组(1.13μg/ml)培养48～72h后用流式细胞术检测凋亡率变化。结果①T细胞的分离纯度为81.3%～94.5%,CD4+T细胞的分离纯度为84%～90%;②(0.14～18μg/ml)氨茶碱共培养人外周血T细胞72h后,其中氨茶碱1.13～18μg/ml组凋亡率差异有统计学意义(P值均<0.05);氨茶碱0.14～0.56μg/ml组凋亡率与阴性对照组比较差异无统计学意义;③氨茶碱1.13μg/ml组干预后,培养CD4+T细胞48～72h,经流式细胞术检测凋亡率,与阴性对照组相比,P值均<0.05,48h的凋亡率与72h者相比,差异有统计学意义(P<0.05)。结论小剂量氨茶碱(1.13μg/ml)可诱导人外周血T细胞和CD4+T细胞凋亡率增加。     

HIV感染者/AIDS患者外周血CD38 HLA-DR分子在CD4+ CD8+T淋巴细胞上的表达

目的　观察国内艾滋病病毒 (HIV)感染者 /艾滋病 (AIDS)患者外周血CD38、HLA DR分子在CD+4 、CD+8T淋巴细胞上表达的变化 ,并探讨这些变化的临床意义。方法　用流式细胞仪检测 5 1例正常对照、14例HIV感染者和 3 6例AIDS患者的外周血CD+4 、CD+8T淋巴细胞表面的CD38、HLA DR分子的表达 ,用分枝DNA(bDNA)法检测 11例HIV感染者和 18例AIDS患者的血浆病毒载量。结果　CD+4 HLA DR+细胞百分比显示 ,AIDS组显著高于正常组及HIV组 ;CD+8HLA DR+T细胞百分比显示HIV组与AIDS组间无差异 ,而它们均显著高于正常组。CD+8、CD38+细胞百分比则是AIDS组 >HIV组 >正常组 ,CD+8CD38+、CD+8HLA DR+、CD+4 HLA DR+细胞百分比与病毒载量显著正相关。结论　在HIV感染过程中 ,HLA -DR+、CD38+在CD+4 、CD+8T淋巴细胞上的表达均显著增加 ,反映T淋巴细胞异常激活 ;尤其是CD+8CD38+细胞百分比随着疾病进展逐渐升高 ,预示疾病进展程度。在评价HIV感染者和AIDS患者的免疫状况时 ,不仅要考虑免疫细胞数量和功能的变化 ,还应考虑免疫细胞的激活水平     

HIV-specific cytotoxic T lymphocyte precursors exist in a CD28-CD8+ T cell subset and increase with loss of CD4 T cells.

OBJECTIVES: To determine whether the CD28-CD8+ T cells that develop during HIV infection contain HIV-specific cytotoxic precursor cells. DESIGN: CD8 subpopulations from six asymptomatic HIV-positive adults, with varying degrees of CD4 T cell loss, were sorted by flow cytometry and HIV-specific precursor cytotoxic T lymphocyte frequencies were measured. Three populations of CD8 T cells were tested: CD28+CD5-- T cells, CD28-CD57+ T cells (thought to be memory cells) and CD28-CD57- T cells (function unknown). METHODS: Sorted CD8 subsets were stimulated with antigen presenting cells expressing HIV-1 Gag/Pol molecules. Cytotoxic T cell assays on Gag/Pol expressing 51Cr-labeled Epstein-Barr virus transformed autologous B cells lines or control targets were performed after 2 weeks. Specific lysis and precursor frequencies were calculated. RESULTS: Both CD28 positive and CD28-CD57+ populations contained appreciable numbers of precursors (9-1720 per 10(6) CD8+ T cells). However, the CD28-CD57- population had fewer precursors in five out of six people studied. More CD28 positive HIV-specific cytotoxic T lymphocyte precursors were found in patients with CD4:CD8 ratios > 1, whereas more CD28-CD57+ precursors were found in patients whose CD4:CD8 ratios were < 1 (r2, 0.68). CONCLUSIONS: Memory HIV-specific precursor cytotoxic T lymphocytes are found in both CD28 positive and CD28-CD8+ cells, however, a CD28-CD57- subpopulation had fewer. Because CD28-CD57+ cells are antigen-driven with limited diversity, the loss of CD28 on CD8 T cells during disease progression may reduce the response to new HIV mutations; this requires further testing.     

非酒精性脂肪性肝病患者外周血恒定自然杀伤T细胞和CD4+/CD8+T细胞活化差异研究*

目的 分析不同非酒精性脂肪性肝病(NAFLD)患者外周血恒定自然杀伤T细胞(iNKT)、CD4⁺和CD8⁺ T细胞活化标记物(CD69、CD25、HLA-DR和NKG2D)的表达差异。方法 2020年1月～2022年7月我院诊治的NAFLD患者64例和同期健康体检者50例,对NAFLD患者行肝穿刺活检,使用流式细胞仪检测外周血iNKT、CD4⁺和CD8⁺T细胞CD69、CD25、HLA-DR和NKG2D表达。结果 在64例NAFLD患者中,经组织病理学检查,诊断NAFL 37例和NASH 27例;健康对照者、NAFL和NASH患者健康对照者、NAFL和NASH患者外周血CD69⁺iNKT细胞百分比分别为(10.1±1.7)%、(6.1±1.3)%和(26.7±3.6)%(P<0.05),CD25⁺iNKT细胞百分比分别为(83.0±5.9)%、(94.1±8.0)%和(90.8±7.5)%(P<0.05),HLA-DR⁺iNKT细胞百分比分别为(15.3±1.7)%、(15.8±2.0)%和(22.3±2.0)%(P>0.05),NKG2D⁺iNKT细胞百分比分别为(44.5±3.5)%、(59.7±4.0)%和(71.3±6.0)%(P<0.05);外周血CD69⁺CD4⁺ T细胞百分比分别为(0.7±0.2)%、(0.4±0.1)%和(0.5±0.1)%(P>0.05),CD25⁺CD4⁺ T细胞百分比分别为(1.4±0.6)%、(3.0±1.3)%和(1.5±0.7)%(P>0.05),HLA-DR⁺CD4⁺ T细胞百分比分别为(2.7±0.7)%、(4.1±1.0)%和(3.9±1.0)%(P<0.05),NKG2D⁺CD4⁺ T细胞百分比分别为(1.6±0.5)%、(0.6±0.2)%和(0.9±0.2)%(P<0.05);外周血CD69⁺CD8⁺ T细胞百分比分别为(2.0±0.4)%、(1.6±0.3)%和(2.1±0.6)%(P>0.05),CD25⁺CD8⁺ T细胞百分比分别为(1.3±0.3)%、(1.1±0.2)%和(1.0±0.2)%(P>0.05),HLA-DR⁺CD8⁺ T细胞百分比分别为(5.0±0.7)%、(6.5±1.0)%和(9.6±1.4)%(P<0.05),NKG2D⁺CD8⁺ T细胞百分比分别为(0.6±0.1)%、(0.5±0.1)%和(0.9±0.2)%(P<0.05)。结论 本研究发现NAFL与NASH患者可能存在外周血iNKT细胞、CD4⁺和CD8⁺ T细胞活化的免疫表型差异,显示NASH患者CD69⁺iNK T细胞百分比增高,可能对诊断有帮助,值得进一步研究。