CD4+ T cells in lung tissue predict responsiveness to cyclosporin A in interstitial pneumonia

OBJECTIVE: A limited number of case studies have demonstrated the steroid-sparing and disease stabilization effects of cyclosporin A (CsA) combined with corticosteroid in patients with chronic interstitial pneumonia (IP). Although CsA is known to inhibit the proliferation and function of CD4+ T cells, it is not clear what type of IP is responsive to CsA administration. METHODOLOGY: In order to evaluate whether any lymphocyte subsets in alveolar tissue predict the responsiveness to CsA, morphometric analysis was performed on lung tissue obtained from six IP patients who were treated with a combination of CsA and steroid because the therapeutic effect of steroid alone had been limited. RESULTS: Cell densities of CD4+ T cells were significantly decreased in the alveolar tissues obtained from CsA responders (n = 3) compared to non-responders (n = 3) (120 +/- 86/mm2 vs 503 +/- 172/mm2, P=0.0495). CD4/CD8 ratios of CsA responders were also significantly lower than those of non-responders (0.315 +/- 0.070 vs 1.975 +/- 0.965, P=0.0463). However, cell densities of CD8+ T cell and areas of B cells aggregates were similar in both groups. CONCLUSIONS: The present observations, contrary to expectation, reveal that lower cell densities of CD4+ T cells and lower CD4/CD8 ratios are associated with responsiveness to CsA in combination therapy, suggesting that pharmacological actions other than suppression of CD4+ T cells explain the efficacy of CsA in patients with chronic IP.     

The role of CD4+ and CD8+ T cells in protective immunity to the murine nematode parasite Trichuris muris

The role ofCD4⁺ and CD8⁺ T cells in protective immunity to Trichuris muris was studied in CD4⁺ or CD8⁺ or both CD4⁺ and CD8⁺ T cell-depleted BALB/c mice. To assess in vivo depletion of T-cell subsets, CD4⁺ and CD8⁺ T cells in the Peyer's patches, the mesenteric lymph nodes (MLN), and the spleens of mice treated with T cell-specific monoclonal antibodies (MoAbs) were analysed by FACS. CD4⁺ T cells were selectively depleted in mice injected with anti-CD4 MoAb i.p. and injection of anti-CD8 MoAb resulted in selective depletion ofCD8⁺ T cells. The expulsion ofl. muris was inhibited in CD4⁺ T cell-depleted mice and numerous worms were detected in the large intestine on days 14 and 21 after infection, although no suppression of protective immunity to T. muris was observed in CD8⁺ T cell-depleted mice. Moreover, there was no difference in suppression of protective immunity to T. muris between CD4⁺ T cell-depleted and both CD4⁺ and CD8⁺ T cell-depleted mice. These results indicate that CD4⁺ T cells play a central role in protective immunity to T. muris infection.     

肺结核患者外周血CD_4~+、CD_8~+T细胞Blimp-1表达下降

目的研究活动性肺结核患者外周血单个核细胞(PBMCs)Blimp-1的表达及临床意义。方法采集31例活动期肺结核患者和45位健康对照组外周血,纯化PBMCs,用结核分枝杆菌ESAT-6和CFP-10混合性抗原肽库刺激,通过细胞表面标记和细胞内细胞因子染色技术,采用流式技术检测CD+4、CD+8T细胞Blimp-1的表达。结果与对照组比较,肺结核患者PBMCs中的CD+4、CD+8T细胞亚群分布出现显著性下降,且肺结核患者CD+4T细胞中Blimp-1的表达比例(%)下降(肺结核组89.5%(83.8%,95.7%),对照组94.5%(89.8%,98.7%),P0.05),且CD+4、CD+8T细胞中Blimp-1的表达量(平均荧光强度)也显著性下降(CD+4T细胞:肺结核组9.28(7.5,18.9),对照组15.4(11,25.4),P0.05);CD+8T细胞:肺结核组9.01(6.08,14.7),对照组14.2(9.53,23.1),P0.05)。结论活动期肺结核CD+4、CD+8T细胞群内Blimp-1的表达下降可能会使效应性和调节性T细胞的分化出现异常。Blimp-1可能参与结核病的疾病进程,这为研究结核病的诊断和治疗提供了线索。     

Interferon-gamma and interleukin-4 reciprocally regulate CD8 expression in CD8+ T cells

The CD8 co-receptor can modulate CD8⁺ T cell function through its contributions to T cell receptor (TCR) binding and signaling. Here we show that IFN-γ and IL-4 exert opposing effects on the expression of CD8α mRNA and surface CD8 protein during CD8⁺ T cell activation. IL-4 caused down-regulation of surface CD8 on ovalbumin (OVA)_257–264-specific TCR-transgenic OT-I CD8⁺ T cells activated with OVA_257–264-coated antigen presenting cells or polyclonal stimuli, and on wild type CD8⁺ T cells activated with polyclonal stimuli. This effect was enhanced in each case when the cells lacked a functional IFN-γ or IFN-γR gene. When WT or IFN-γ-deficient OT-I CD8⁺ T cells were analyzed 9 days after co-injection with control or IL-4-expressing OVA⁺ tumor cells into RAG-2^−/−γc^−/− mice, CD8 levels were highest on WT donor cells from mice that received the control tumor and lowest on IFN-γ-deficient donor cells from mice that received the IL-4-expressing tumor. The latter CD8^low cells displayed markedly impaired binding of OVA_257–264/MHC tetramers and peptide/MHC-dependent degranulation. The data reveal an unexpected role for IFN-γ in tuning the CD8 co-receptor during primary CD8⁺ T cell activation both in vitro and in vivo.     

CD8~+ T细胞在早期内毒素血症对心功能的损害作用

目的:探讨CD8+T细胞在早期内毒素血症心脏损伤中的浸润及其对心功能的影响。方法:野生雄性小鼠20只随机分为野生对照组和野生内毒素血症组,每组各10只;CD8敲除雄性小鼠10只,随机分为CD8敲除对照组和CD8敲除内毒素血症组,每组各5只。对照组均给予0.9%氯化钠液腹腔注射,内毒素血症组均给予脂多糖腹腔注射。6 h显微超声检测射血分数及短轴缩短分数;即刻处死并收取野生对照组及野生内毒素血症组各3只小鼠心脏组织,流式细胞技术检测心脏细胞悬液中巨噬细胞(F4/80+细胞)及CD8+T细胞、CD4+T细胞分布;其余小鼠心脏组织进行病理切片HE染色,观察心肌纤维断裂及炎症细胞浸润。结果:与野生对照组相比,野生内毒素血症组射血分数及短轴缩短分数显著降低(均为P<0.05);野生内毒素血症组F4/80+细胞、CD4+T细胞及CD8+T细胞均显著增加(均为P<0.05)。与野生内毒素血症组相比,CD8基因敲除内毒素血症组射血分数及短轴缩短分数均显著升高(均为P<0.05)。结论:急性内毒素血症导致心肌纤维损伤、心功能不全,心脏组织CD8+T等炎症细胞浸润;而缺乏CD8+T细胞时则减轻内毒素血症导致的心功能损伤,提示CD8+T细胞在急性内毒素血症诱导的心功能不全早期发挥重要作用。     

CD4+ T lymphocytes contribute to protective immunity induced in sheep and goats by Haemonchus contortus gut antigens

Immunization with parasite antigens derived from the gut of adult Haemonchus contortus induces significant levels of protection against the parasite in sheep and goats. However, the mechanisms of immunity involved in this protection are not clear. Here, we investigate the requirement for CD4⁺ T lymphocytes in gut antigen-induced immunity against H. contortus. Gut antigen immunized animals were depleted (>98%) of their CD4⁺ T lymphocytes in peripheral blood by intravenous injection of an anti-CD4 MoAb. Depletion in peripheral blood persisted for at least eight days, after which there was gradual recovery of CD4⁺ T lymphocytes. Serum antibody levels in gut antigen-immunized animals correlated significantly with worm parameters, suggesting a contribution by antibody to the immunity observed. By covariate analysis, using ELISA OD as the covariate, CD4⁺ T lymphocyte depletion was shown to partially abrogate immunity induced by gut antigen immunization, against challenge infection with H. contortus. The greatest effect of CD4⁺ T lymphocyte depletion was observed at 14 days post-infection, with differences between CD4⁺ T lymphocyte depleted and intact animals less apparent between days 21 and 25. Collectively, our data indicate that CD4⁺ T lymphocytes contribute to immunity induced by gut antigens. Our results also suggest that antibody works synergistically with CD4⁺ T lymphocytes to confer this immunity.     

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.     

The role of CD8+ cells in the establishment and maintenance of a Trichuris muris infection

Chronic infection by the caecal-dwelling intestinal murine nematode Trichuris muris occurs if given as a high-dose infection to 'susceptible' AKR mice or as a low-dose infection to the normally 'resistant' C57BL/6 mouse strain. Both regimes result in a type 1 cytokine response, i.e. high levels of IFN-gamma and IL-12. Here we show this susceptible response is associated with a large population of CD8(+) IFN-gamma(+) cells within the mesenteric lymph nodes and numerous CD8(+) cells infiltrating the caecal mucosa. Despite this, the in vivo abolition of CD8(+) cells within AKR and C57BL/6 mice, either prior to infection or once infection has become established, failed to affect chronicity, implying that CD8(+) T cells are not essential for the initiation or maintenance of the susceptible response to T. muris. Interestingly, the percentage of IFN-gamma(+) CD4(+) cells increased in treated groups, perhaps in a compensatory role. The majority of antigen-specific cytokine responses were comparable in both treated and control groups, although IL-5 was fivefold higher in animals receiving anti-CD8 mAbs and IFN-gamma was also raised in treated mice. Mastocytosis was unaltered by CD8 depletion, however, paradoxically, eosinophilia within the caecum was reduced in treated mice. Together these data clearly demonstrate that CD8(+) T cells are associated with chronic T. muris infection; however, these cells are dispensable for both the early and late phases of this response, but do appear to play a role in the regulation of certain cytokines and caecal eosinophilia.     

CD8+ T cells suppress autologous megakaryocyte apoptosis in idiopathic thrombocytopenic purpura

To investigate the effect and mechanism of the CD8⁺ T cells in bone marrow on autologous megakaryocytopoiesis in idiopathic thrombocytopenic purpura (ITP) patients, we prepared bone marrow mononuclear cells (MNCs) from 15 chronic ITP patients and 13 controls. MNCs were cultured in vitro directly (MNC group) or after depleting CD8⁺ T cells (CD8⁺ T-dep group) or adding purified autologous CD8⁺ T cells to CD8⁺ T-dep MNCs (Coculture group) or adding dexamethasone to the coculture (DEX group) all in semi-solid and liquid culture systems. The quantity and quality of megakaryocytes were measured. The megakaryocyte count was increased in the presence of autologous CD8⁺ T cells of patients with chronic ITP, while platelet production was reduced. In addition, lower percentages of polyploidy and apoptotic megakaryocytes, and higher levels of soluble Fas (sFas) in supernatant were observed. Dexamethasone successfully corrected this effect of CD8⁺ T cells on autologous megakaryocytopoiesis. These studies provide evidence that activated CD8⁺ T cells in bone marrow of patients with chronic ITP might suppress megakaryocyte apoptosis, leading to impaired platelet production. Megakaryocyte apoptosis would be a novel target for the management of ITP.     

原发性肝癌患者外周血CD4+T、CD8+T、Tc17、Th17和Treg淋巴细胞的变化及其意义

目的 了解原发性肝癌(PLC)患者外周血CD4+T、CD8+T、Tc17、Th17和Treg淋巴细胞的变化.方法 2018年6月～2019年12月我院诊治的PLC患者83例(巴塞罗那临床肝癌分期A期25例,B期23例,C期18例,D期17例)和健康人35例,采用流式细胞技术检测外周血CD4+T、CD8+T及Tc17(C...     

CD4~+ CD25~+调节性T细胞与恶性腹水的相关研究进展

CD4+ CD25+调节性T细胞(CD4+ CD25+Treg细胞)是具有独特免疫调节功能的T细胞亚群,抑制免疫反应,在机体免疫稳态维持、肿瘤免疫及移植耐受等方面发挥重要的作用。近年来,调节性T细胞在肿瘤免疫及治疗的研究中受到越来越广泛的关注。现就调节性T细胞在恶性腹水方面的研究做一简要综述。     

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。     

CD4CD4+和CD8CD4+ T淋巴细胞与动脉粥样硬化相关性研究进展

在动脉粥样硬化的发生发展过程中CD4+和CD8+T淋巴细胞有着重要的意义,近年来越来越多的研究显示了CD4+和CD8+T淋巴细胞参与了动脉粥样硬化的免疫炎症反应,受到了国内外学者的关注,同时,也成为心血管领域和免疫学界难以攻关的课题。本文对CD4+和CD8+T淋巴细胞与动脉粥样硬化相关性研究进展做一简要综述。     

Induction of CD4+CD8+ double positive T cells and increase in CD5+ B cells in efferent lymph in sheep infected with Trypanosoma evansi

The effects of Trypanosoma evansi on efferent lymphocyte phenotypes draining from a lymph node primed with Pasteurella haemolytica vaccine were studied in sheep. The prefemoral efferent lymphatic ducts of the infected sheep along with those of two uninfected sheep were surgically cannulated. Lymph was collected and lymphocytes recovered from it analysed by two-colour indirect immunofluorescence staining and cytofluoremetry in a fluorescence activated cell analyser (FACSCAN). The study showed the appearance and persistence of T. evansi in the efferent lymph for a long period of time and the appearance of CD4⁺CD8⁺ (double positive, DP) T lymphocytes in the efferent lymph of infected animals. The infection also resulted in increases in CD5⁺ B cells in the prefemoral efferent lymph. In addition, there were decreases in the output of conventional B cells, CD5⁺ and CD4⁺ T cell subsets but large increases in CD8⁺ cells followed by terminal depletion of all cell subsets. In contrast, inoculation of sheep with pasteurella vaccine antigen alone produced little alterations in the proportions, but large increases in the numbers of all T cell subsets except that of CD8⁺ cells which also showed little variation; and there was a concurrent increase in the numbers and proportions of efferent B cells. In addition, the abnormal expression of DP and CD5⁺ B cells did not occur in the uninfected vaccinated sheep. It is concluded that these abnormal changes in the kinetics of efferent lymphocyte phenotypes are likely to play a role in the genesis of the generalized immunosuppression seen in trypanosome-infected hosts.     

支气管哮喘大鼠CD4+CD25+T细胞的变化及地塞米松干预作用的研究

目的 研究支气管哮喘(简称哮喘)大鼠模型支气管肺泡灌洗液(BALF)、血液、脾脏CD4+CD25+T细胞的变化,及地塞米松对CD4+CD25+T细胞的影响.方法 50只SD大鼠随机分为5组,空白对照(A)组,哮喘(B)组,地塞米松1(C)组、地塞米松2(D)组,地塞米松3(E)组.A组第l天给予腹腔注射生理盐水l ml,第15～21天每天给予生理盐水雾化.B、C、D、E组用卵蛋白建立哮喘大鼠模型,第1天,每只大鼠腹腔注射抗原l ml(卵蛋白1 mg+灭活百日咳杆菌9×106个+氢氧化铝干粉100 mg)混悬液,第15～21天给予1%的卵蛋白雾化30 min,C、D、E组于雾化后分别给予腹腔注射地塞米松0.2 mg/kg、1 mg/kg、2 mg/kg.采用流式细胞仪检测的方法 ,观察大鼠体内BALF、外周血、脾脏CD4+CD25+T细胞的变化及使用不同剂量地塞米松后对其的影响.结果 B组BALF、外周血、脾脏CD4+CD25+T细胞表达占CD4+T细胞的百分比分别是(42.21±5.62)%、(12.69±2.70)%、(11.15±1.05)%,A组结果 分别是(18.76±5.85)%、(6.21±1.73)%、(7.85±2.13)%.B组与A组比较,差异均具有统计学意义(P＜0.01,P＜0.01,P＜0.05);C组、D组、E组BALF中CD4+CD25+T细胞占CD4+T细胞的百分比表达分别是(10.49±4.03)%、(13.28±5.12)%、(7.51±5.39)%,显著低于A组和B组,(P＜0.05,P＜0.01);外周血中,C组(6.03±1.43)%、D组(4.88±0.95)%与A组(6.21±1.73)%比较,差异无统计学意义,E组(3.49±0.62)%与C组、A组比较,差异有统计学意义(P＜0.05).脾脏中,C组(7.25±1.82)%、D组(8.63±3.18)%与A组(7.85±2.13)%比较,差异无统计学意义,E组(3.38±1.37)%与C组、D组、A组比较,差异有统计学意义(P＜0.05).结论 CD4+CD25+T细胞在哮喘大鼠体内有明显的优势表达,可能是哮喘发病的机制之一.地塞米松可以抑制CD4+CD25+T细胞的表达.BALF内CD4+CD25+T细胞的变化与外周血和脾脏的变化具有一致性,监测外周血或脾脏CD4+CD25+T细胞变化可了解肺部情况.     

Protective and pathogenic roles of CD8+ T cells during malaria infection

CD8+ T cells play a key role in protection against pre-erythrocytic stages of malaria infection. Many vaccine strategies are based on the idea of inducing a strong infection-blocking CD8+ T cell response. Here, we summarize what is known about the development, specificity and protective effect of malaria-specific CD8+ T cells and report on recent developments in the field. Although work in mouse models continues to make progress in our understanding of the basic biology of these cells, many questions remain to be answered - particularly on the roles of these cells in human infections. Increasing evidence is also emerging of a harmful role for CD8+ T cells in the pathology of cerebral malaria in rodent systems. Once again, the relevance of these results to human disease is one of the primary questions facing workers in this field.     

Aging and CD8+ T cell immunity to respiratory virus infections

The capacity of the immune system to mediate effective immune responses to pathogens declines with age. In the case of immune responses to newly encountered antigens, several studies have demonstrated that this decline reflects both a loss of naïve T cells and changes in the repertoire and function of these cells over time. However, comparatively little is known about the impact of age on established memory T cells pools. Here we discuss age-related changes in memory CD8⁺ T cell pools elicited by influenza and parainfluenza viruses and the impact of these changes on immunity in general.     

In vitro cytotoxicity of CD8+ T cells in multi-drug-resistant tuberculosis. A preliminary report

Background and objective:   Specific CD8+ T-cell cytotoxicity has been recognized as being involved in the elimination of drug-susceptible tuberculosis (DS-TB). Given that there is currently no information on the cytotoxic effector functions of CD8+ T cells in multi-drug-resistant tuberculosis (MDR-TB), our objective was to analyse the cytotoxic activity, both basal and stimulated, of CD8+ T cells from MDR-TB patients and compare it with that of DS-TB patients, as well as purified protein derivative (PPD)+ and PPD− subjects.
Methods:   Cytotoxic activity of CD8+ T cells from MDR-TB patients, DS-TB patients, PPD+ and PPD− subjects was measured by a colorimetric assay, using H37Rv culture filtrate protein as the antigenic stimulus.
Results:   Twenty-eight subjects were studied (7 MDR-TB patients, 7 DS-TB patients, 7 PPD+ subjects and 7 PPD− subjects). In the presence of the antigenic stimulus, the cytotoxic activity of CD8+ T cells from MDR-TB patients (% lysis) increased from 6.7% to 59.6% ( P  < 0.001). In DS-TB patients lysis increased from 3.2% to 22.5% ( P  < 0.001), whereas in PPD+ subjects it increased from 2.7% to 12.0% ( P  < 0.001) and in PPD− subjects from 1.3% to 3.2% ( P  < 0.001). Basal cytotoxic activity was significantly higher for MDR-TB patients than PPD+ and PPD− subjects ( P  = 0.003), but not compared with that for DS-TB patients ( P  = 0.05). Stimulated cytotoxic activity was highest for MDR-TB patients.
Conclusions:   CD8+ T cells from MDR-TB patients showed an exaggerated cytotoxic activity after antigenic stimulation. Further studies are required to elucidate the role of this response in the immunopathogenesis of MDR-TB.