CD4 T lymphocyte activation in BLV-induced persistent B lymphocytosis in cattle

Bovine leukemia virus (BLV) is an oncogenic retrovirus in the human T cell leukemia virus family. BLV infects B lymphocytes and induces a nonmalignant persistent lymphocytosis (PL) and leukemia/lymphoma in cattle. There is evidence that CD4 T lymphocytes are activated during BLV infection and promote the development of PL. How CD4 T lymphocytes are activated by BLV infection is not known. We observed that CD4 T lymphocytes from PL cattle proliferated in the presence of autologous, irradiated peripheral blood mononuclear cells (PBMC), whereas no proliferation occurred in cell cultures from BLV-infected non-PL cattle. Proliferation required direct contact with metabolically active irradiated PBMC but was not associated with viral protein expression or inhibited by antibodies to BLV. Unexpectedly, B lymphocytes alone failed to account for the irradiated PBMC stimulation of CD4 T lymphocytes. These observations and the magnitude of the proliferative response suggest that activation is polyclonal and involves mechanisms other than BLV antigen-specific stimulation.     

癌灶CD4~+CD25~+和CD8~+ T细胞亚群与卵巢浆液性癌患者生存期相关

检测卵巢浆液性癌患者癌组织中CD4+CD25+及CD8+T细胞的数目,探讨其两种T细胞介导的免疫功能对疾病发展及预后的影响。免疫组织化学双标及单标的染色方法检测41例卵巢浆液性癌患者手术切除癌组织标本中CD4+CD25+和CD8+T细胞的数目。结果显示,癌灶中CD4+CD25+T淋巴细胞为(19.95±11.50)个/10HPF,CD8+T淋巴细胞为(43.46±16.69)个/10HPF。生存分析发现高CD4+CD25+T细胞组患者总生存期较低CD4+CD25+T细胞组缩短,差异有显著性(P<0.05);而高CD8+T细胞组患者总生存期与低CD8+T细胞组相比延长,且差异有显著性(P<0.05),此外两种T细胞数目与患者年龄、病理分级、临床分期、腹水细胞学及淋巴结转移等临床病理因素均无关(P>0.05)。结果表明,卵巢浆液性癌中高CD4+CD25+T细胞提示患者预后不良,可能与CD4+CD25+T细胞介导的免疫抑制导致肿瘤免疫逃逸有关;癌组织中高CD8+T细胞提示患者预后较好,两种T细胞对卵巢浆液性癌预后的评估有重要的价值,同时可以通过阻断CD4+CD25+T细胞的免疫抑制作用改善卵巢浆液性癌患者的预后,为卵巢癌治疗提供靶目标。     

CD4+T淋巴细胞的活化在HIV-1感染长期非进展者及典型进展者之间差异的研究

目的了解CD4 T淋巴细胞的活化在长期感染非进展者(LTNP)及典型进展者(TP)之间的差异,探讨HIV感染的免疫基础。方法收集24例HIV-1感染患者(7名LTNP患者,17名TP患者)及15例健康对照的抗凝血标本,流式细胞术检测CD4 T淋巴细胞的活化标志物CD38并检测其CD4计数等指标;bDNA方法检测患者体内的病毒载量。结果与正常人相比,LTNP患者的CD4 T淋巴细胞的活化的差异无统计学意义(P>0.05)而TP患者的活化程度明显增高(P<0.01);HIV感染者CD4 T淋巴细胞CD38的表达水平与CD4计数呈正相关,与病毒载量呈负相关。结论随着疾病的进展,CD4 T淋巴细胞的活化程度逐渐增高;LTNP患者CD4 T淋巴细胞的活化程度没有明显增高可能是其疾病长期不进展的原因之一。     

Immunoregulatory CD4+ CD45R+ suppressor/inducer T lymphocyte subsets and impaired cell-mediated immunity in patients with Down''s syndrome.

The monoclonal antibodies 2H4 and 4B4 allow CD4+ and CD8+ T lymphocytes to be subdivided into CD45R+ and CDW29+ functional subpopulations. The CD4+ CD45R+ lymphocytes are designated as suppressor/inducer and CD4+ CDW29+ as helper/inducer subsets. Peripheral blood lymphocytes from 19 patients with Down's syndrome and 19 age- and sex-matched normal controls were analysed for the CD45R+ and CDW29+ subsets from the CD4+ and CD8+ T lymphocytes. The percentage of CD4+ CD45R+ cells (suppressor inducer) was markedly increased and of CD4+ CDW29+ cells (helper/inducer) decreased in all patients with Down's syndrome. In contract, the percentage of CD8+ CD45R+ and CD8+ CDW29+ subsets showed no major differences between patients with Down's syndrome and normal controls. Moreover, an alteration in the CD4+ and CD45R+ and CD4+ CDW29+ T cell subsets was accompanied by a markedly reduced proliferative response to phytohaemagglutinin and concanavalin A stimulation of the CD4+ T lymphocytes. Thus, a deficiency exists in patients with Down's syndrome in the CD4+ CDW29+ helper/inducer T cell subset which may contribute to their impaired cell-mediated immunity.     

RA患者外周血CD8＋CD28-和CD4＋CD25＋调节性T细胞的表达及疾病活动性指标相关性分析

目的：检测类风湿性关节炎（RA）患者外周血CD8＋CD28-、CD4＋CD25＋调节性T细胞亚群,探讨其与临床活动性指标的关系。方法：采用流式细胞术检测台州医院RA患者外周血CD8＋CD28-、CD4＋CD25＋ T细胞亚群比例,探讨调节性T细胞与RA活动性、类风湿因子（RF）、免疫球蛋白（Ig）、C反应蛋白（CRP）、补体C3、抗CCP抗体、抗核抗体（ANA）、血小板（PLT）及血沉（ESR）的关系。结果：活动期RA患者外周血CD4＋CD25＋调节性T细胞亚群比例显著低于正常对照组（P〈0.01）,但稳定期RA患者与正常对照组结果差异无统计学意义（P〉0.05）。活动期和稳定期RA患者CD8＋CD28-与正常对照组相比较,结果无统计学意义（P〉0.05）;CD4＋CD25＋与CRP密切相关（r=-0.593,P〈0.05）,CD8＋CD28-与ESR相关系数呈弱相关。CD4＋CD25＋和CD8＋CD28-细胞与RF、IGG、C3、ANA、anti-CCP和PLT未见明显相关性。结论：活动期RA患者外周血CD4＋CD25＋ T细胞亚群比例减少,CD4＋CD25＋ T细胞可能与类风湿性关节炎疾病进展有关。     

Circulating CD4+CD8+ T lymphocytes in patients with Kawasaki disease

We serially monitored cell surface antigen expression on mononuclear cells in peripheral blood isolated from patients with Kawasaki disease (KD), and found, for the first time, that a markedly increased number of CD4⁺CD8⁺ T lymphocytes was present in some of the patients (11 of the 24 cases). The cases of five of these 11 patients were complicated with coronary artery lesion (CAL); the 13 patients with normal numbers of CD4⁺CD8⁺ T lymphocytes did not have CAL. The patients' age, sex and grade of systemic inflammation evaluated by peripheral leucocyte count and serum C-reactive protein levels were not correlated to the number of CD4⁺CD8⁺ T lymphocytes. Other cell surface antigen characteristics of the CD4⁺CD8⁺ T lymphocytes included CD3⁺, CD45RA⁺, CD45RO⁺, CD16^?, and HLA-DR⁺. These results indicate that the surface antigen characteristics of the KD peripheral blood examined were the same as those of Epstein–Barr virus infection without CD45RA⁺. These findings provide useful information for the analysis of the pathogenesis of KD.     

中国恒河猴(Macaca mulatta)外周血CD4+CD25+T淋巴细胞的研究

目的:研究中国恒河猴外周血中CD4 CD25 T淋巴细胞亚群及其分布频率。方法:利用流式细胞术对50只中国恒河猴外周血CD4 CD25 T淋巴细胞进行了分析。结果:发现所有被检测的恒河猴个体中均存在明显的CD4 CD25 T淋巴细胞亚群;CD4 CD25 T淋巴细胞大约占CD4 T淋巴细胞的9.1%(变化范围为2.6%～18.1%);其中CD4 CD25highT淋巴细胞约占2.5%(0.3%～5.5%)。对不同年龄和性别个体中CD4 CD25 T淋巴细胞频率的初步分析未发现统计学上有年龄或性别差异。结论:中国恒河猴可用于与CD4 CD25 T细胞相关的人类疾病的研究中。     

Peripheral T lymphocyte depletion by apoptosis after CD4 ligation in vivo: selective loss of CD44- and 'activating' memory T cells.

We have demonstrated that a single intravenous bolus of rat anti-CD4 MoAb caused a small but prolonged increase in apoptosis in murine lymph nodes. We have quantified this process using the novel Highly Optimized Microscope Environment (HOME) interactive images analysis system and shown that the increase in apoptosis was sufficient to account for the observed depletion of the peripheral CD4+ T cell subset. This occurred in the absence of any other exogenous signal. Furthermore, there was no evidence of an inflammatory or necrotic response in the tissues, indicating that this was unlikely to be Fc or complement-mediated antibody killing. The anti-CD4-induced depletion selectively removed CD44- T cells. Using mice previously immunized with yeast-derived HIV-1 p24 recombinant protein there was sparing of memory T cell function after in vivo anti-CD4 treatment, except during a window of less than 24 h duration, when simultaneous exposure to antigen and anti-CD4 antibody resulted in the depletion of specific memory T lymphocyte function. This indicated that a very minor alteration in the frequency of apoptosis had a marked effect on cell number over time, and suggested that opportunistic infection associated with CD4+ T cell depletion may be explained by loss of memory cells when there is antigenic stimulation at the same time as CD4 ligation. These results have implications for the pathology of HIV-associated disease which is associated with ligation of CD4 molecules in vivo.     

Human mucosal CD4+ T cells but not blood CD4+ T cells respond vigorously towards CD28 engagement

Human lamina propria T lymphocytes (LPT) possess functional properties profoundly different from those of peripheral blood T lymphocytes (PBT). While they are characterized by a low proliferative response to T cell receptor (TCR)/CD3 stimulation in vitro their responsiveness to activation through the 'co-stimulatory' CD2-receptor is enhanced when compared to PBT. In this study, we demonstrate that engagement of another co-stimulatory receptor on both LPT and PBT, namely CD28, by a single monoclonal antibody (mAb), respectively, strongly activates the former but not the latter through a PI3-kinase dependent signalling pathway leading to the production of inflammatory cytokines such as interleukin (IL)-2, tumour necrosis factor (TNF)-α, interferon (IFN)-γ and granulocyte-macrophage colony-stimulating factor (GM-CSF). In addition to the high sensitivity of LPT to CD2 stimulation, this finding supports the notion that 'non-specific/innate' mechanisms to activate T lymphocytes play a predominant role vis-à-vis'TCR driven/adaptive' responses in the intestinal mucosa. Furthermore, it suggests that results from preclinical tests for therapeutic antibodies performed with human blood derived T cells are probably insufficient to predict reactivities of tissue-resident immune cells, which--given their quantitative predominance--may critically determine the in-vivo response to such compounds.     

CD4-mediated functional activation of human CD4+CD25+ regulatory T cells

Naturally occurring CD4(+)CD25(+)FoxP3(+) regulatory T cells (CD25(+) Tregs) constitute a specialized population of T cells that is essential for the maintenance of peripheral self-tolerance. The immune regulatory function of CD25(+) Tregs depends upon their activation. We found that anti-CD4 antibodies activate the suppressive function of human CD25(+) Tregs in a dose-dependent manner. We demonstrate that CD4-activated CD25(+) Tregs suppress the proliferation of CD4(+) and CD8(+) T cells, their IL-2 and IFN-gamma production as well as the capacity of CD8(+) T cells to re-express CD25. By contrast, anti-CD4 stimulation did not induce suppressive activity in conventional CD4(+) T cells. These results identify CD4 as a trigger for the suppressive function of CD25(+) Tregs and suggest a possible CD4-mediated exploitation of these cells.     

存放温度及时间对于HIV/AIDS患者外周血CD4+、CD8+细胞测定结果的影响

目的　研究HIV AIDS患者外周血CD4 、CD8 淋巴细胞数在不同条件下 (时间、温度和处理过程 )的变化。方法　选取HIV AIDS患者 34例 ,用流式细胞术检测在 4℃条件下放置不同时间(2、2 4、4 8、72h)的外周血CD4 、CD8 细胞数的变化 ,对经过处理的外周血 (处理过的血样 )CD4 、CD8 细胞数的变化进行比较 ;对室温条件下放置不同时间 (2、2 4、4 8、72h)处理过的血样CD4 、CD8 细胞数的变化进行比较。结果　在 4℃时 ,全血放置 2、2 4、4 8、72h的CD4 细胞计数差异无显著意义(P >0 0 5 ) ,而CD8 细胞数放置 72h时则差异有显著意义 (P <0 0 5 ) ;处理过的样品放置 72hCD4 细胞计数差异才有显著意义 (P <0 0 5 ) ,而CD8 细胞数在 2 4h时差异就有显著意义 (P <0 0 5 )。在室温时 ,处理过血样放置 2、2 4、4 8、72h的CD4 细胞计数差异无显著意义 (P >0 0 5 ) ,而CD8 细胞数在 4 8h则差异有显著意义 (P <0 0 5 )。结论　抗凝全血在 4℃放置 4 8h ,检测CD4 、CD8 淋巴细胞数 ,结果是可靠的。处理过血样在室温放置 2 4h ,检测CD4 、CD8 淋巴细胞数 ,结果是可靠的。 2 4～4 8h虽然CD4 淋巴细胞没有变化 ,但CD8 淋巴细胞却发生明显的变化 ,两者比例必然发生变化。     

Assessment of alloreactive T cell subpopulations of aged mice in vivo. CD4+ but not CD8+ T cell-mediated rejection response declines with advanced age

The present investigation explored age-related alterations in T cell populations mediating allospecific responses in vivo. Healthy aged and young H-2^b and H-2^bxH-2^k mice were engrafted with major histocompatibility complex (MHC) class II-disparate bm12 skin, rejection of which requires CD4⁺ T cells, and MHC class I-disparate bm1 skin, rejection of which requires CD8⁺ T cells. Aged mice of both genders exhibited prolonged survival of bm12 skin grafts relative to their young counterparts but rejected bm1 skin grafts at a rate equivalent to that of young mice. Consistent with prolonged survival of bm12 skin grafts, markedly diminished levels of Ia^bm12 CTL activity were elicited from T cells of aged mice in vitro. However, no such decline was observed in the level of K^bm1 CTL from T cells of aged mice. The alterations in Ia^bm12 allospecific responses were not attributable to quantitative changes in CD4⁺ T cells of aged mice, and addition of soluble T cell helper factors to response cultures of aged mice did not augment Ia^bm12 cytotoxic T lymphocytes activity. These data demonstrate that aging fundamentally affects CD4⁺ T cell-mediated allospecific responses particularly in vivo, and that deficient generation of soluble T cell helper factors alone cannot explain this deficit.     

慢性乙型肝炎患者外周血CD4~+CD25~+Treg与CD4~+和CD8~+ T淋巴细胞亚群的相关研究

目的:探讨慢性乙型肝炎患者外周血中CD4+CD25+调节性T细胞的含量和CD4+CD8+T淋巴细胞亚群分布,两者之间相关性及与HBV的相关性。方法:采用流式细胞术检测50例慢性乙型肝炎患者和20例健康对照者外周血中CD4+CD25high、CD4+CD25+Foxp3+Treg细胞表达及CD3/CD4/CD8 T淋巴细胞亚群,荧光定量PCR法检测HBV DNA含量。结果:慢性乙型肝炎患者外周血中CD4+CD25highTreg明显高于健康对照组(P0.01),且随HBV DNA载量增加,患者外周血中CD4+CD25highTreg细胞的水平逐渐升高。慢性乙型肝炎患者外周血中CD4+CD25+Foxp3+Treg细胞也相应增高,且与CD4+CD25highTreg细胞的变化成正相关(r=0.890,P0.001)。与健康对照组比较,患者组CD4+T细胞百分率及CD4+/CD8+比值均降低,而CD3+T细胞和CD8+T细胞百分率差异无显著性(P0.05)。CD4+CD25highTreg细胞与HBV DNA取对数后成正相关(r=0.782,P0.001),与谷丙转氨酶(ALT)成正相关(r=0.432,P0.005);与CD3+、CD4+、CD8+T细胞水平及CD4+/CD8+比值均无相关性(P0.05)。CD3+、CD4+、CD8+T淋巴细胞及CD4+/CD8+比值与HBV DNA载量之间亦无相关性(P0.05)。结论:慢性乙型肝炎患者外周血中CD4+CD25+Treg细胞增高,且与HBV的复制水平及ALT增高具有一致性,而T细胞亚群是否可作为监测CHB患者免疫状态的指标需进一步探讨。     

Dynamics of the expression of activation marker complex during polyclonal activation of human peripheral blood CD4+ and CD8+ lymphocytesin vitro

A study of the expression of early and late activation markers on the surface of regulatory subsets of human peripheral blood T lymphocytes revealed marked differences between patients with bronchopulmonary pathology and healthy donors in the dynamics of CD25, CD71, and HLA-DR expression. The results are of significance for the evaluation of both the activation state of the cell and its functional potential in the realization of the immune response. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 483–485, November, 1994 Presented by R. V. Petrov, Member of the Russian Academy of Sciences     

慢性乙型肝炎患者CD4~+和CD8~+T细胞亚群的研究

目的:比较不同感染状态慢性乙型肝炎(CHB)患者外周血CD4+和CD8+T细胞亚群的差异。方法:收集CHB患者78例,根据感染状态分为乙型肝炎e抗原(HBeAg)阳性且肝功能正常、HBeAg阳性且肝功能异常和HBeAg阴性3组。13例健康志愿者(正常对照组)来自曙光医院体检中心。应用流式细胞术(FCM)检测不同感染状态CHB患者外周血中CD4+CD25+、CD8+CD28-、CD4+CD95+、CD8+CD95+细胞亚群的分布情况,并对各亚群分布情况与HBeAg和HBVD-NA水平的相关性进行分析。结果:与正常对照组相比,HBeAg(+)肝功能正常组的CD4+CD25+/CD4+和CD4+CD95+/CD4+明显升高(P<0.01,P<0.05),3个感染组CD8+CD28-/CD8+值均明显升高(P<0.01);与HBeAg(+)肝功能正常组相比,HBeAg(+)肝功能异常组和HBeAg(-)组的CD4+CD25+/CD4+明显降低(P<0.01),HBeAg(-)组CD8+CD95+/CD8+明显降低(P<0.05),HBeAg(+)肝功能异常组的CD8+CD95+/CD8+明显降低(P<0.01)。CD4+CD25+/CD4+,CD4+CD95+/CD4+与HBVDNA呈正相关(P<0.01,P<0.05),CD8+CD28-/CD8+与HBVDNA和HBeAg均呈正相关(P<0.01)。结论:CHB患者外周血中CD4+CD25+、CD8+CD28-T、CD4+CD95+细胞表达频率增加,可能对慢性乙肝病毒感染过程中的免疫耐受起一定作用。     

Circulating CD3+ CD4+ CD+ T lymphocytes in multiple sclerosis

Triple-antibody flow cytometry was used to search for distinctive populations of peripheral blood lymphocyte immunophenotypes in multiple sclerosis (MS). Using monoclonal antibodies to the cell surface markers CD3, CD4, and CD8, T cell subsets were quantified on a cohort of 31 MS patients (not treated with corticosteroids for at least 6 months), 30 healthy donors, and 14 patients with other autoimmune diseases (also corticosteroid treatment-free for at least 6 months). Untreated MS patients displayed a significantly greater population of CD3+CD4+CD8+ circulating T cells than healthy donors (P = 0.023). Patients with other autoimmune diseases displayed mean populations of CD3+CD4+CD8+ cells greater than normal donors and less than MS, but not significantly different from either. An additional 45 MS patients who had received corticosteroid therapy within the previous 6 months were phenotyped. Treatment of symptomatic MS with corticosteroids was associated with a smaller population of circulating CD3+CD4+CD8+ cells. Some MS patients have significantly greater numbers of peripheral blood T lymphocytes simultaneously expressing CD3, CD4, and CD8 surface markers than healthy donors and this population of cells may be reduced by corticosteroids treatment. This triple positive phenotype may be a manifestation of a systemic immune abnormality in MS.     

Absence of Epstein-Barr virus-specific, HLA class II-restricted CD4+ cytotoxic T lymphocytes in infectious mononucleosis.

Cytotoxic T lymphocytes (CTL) with the CD4+ phenotype that recognize major histocompatibility complex (MHC) class II antigens are detectable very frequently in cultures of human alloreactive or virus-specific T cells. The significance of these CD4+ CTL for an immune reaction in vivo is not clear. Since Epstein-Barr virus (EBV) transformed B cells express HLA-class I and class II antigens equally well both CD8+ and CD4+ CTL should be stimulated during an acute EBV infection. We analysed the MHC specificity and the phenotype of EBV-specific CTL from patients with infectious mononucleosis (IM). When tested directly without any previous culture, T cells from patients in the acute phase of IM showed specific MHC-restricted cytotoxicity against the autologous B cell line. Addition of a HLA class I specific monoclonal antibody (MoAb) but not of a HLA class II specific MoAb resulted in a complete blocking of the lytic activity. Cell sorting revealed that the entire cytotoxic activity was present in the CD8+ fraction whereas no specific CTL were detectable in the CD4+ fraction. The absence of cytotoxicity in CD4+ cells was not due to a lack of activation of these cells since both CD8+ and CD4+ cells were activated in situ, showing spontaneous growth in interleukin-2 (IL-2) and expressing the activation marker TP103. Frequency estimation revealed that 1/300-1/600 CD8+ but only 1/2000-1/4000 CD4+ T cells gave rise to a specific CTL colony after 10 days. If CD4+ colonies were tested repeatedly for cytotoxicity we found that CD4+ CTL acquired their cytotoxicity during in vitro culture. In addition, we isolated EBV-specific CD4+ T cell clones able to lyse their stimulator cells in the presence but not in the absence of lectin, even after a long period of culture. Taken together our results show that cytotoxicity mediated by CD4+ T cells does not play a role in an anti-viral immune response.     

Cytomegalovirus (CMV) infection, CD4+ lymphocyte counts and the development of AIDS in HIV-1-infected haemophiliac patients.

After a maximum of 11 years (median 8.3 years) from the time of HIV seroconversion, 25 out of 59 (42%) of CMV-seropositive haemophiliacs had progressed to AIDS, as opposed to eight out of 50 (16%) CMV seronegatives. The age-adjusted relative risk for AIDS among CMV seropositives was 2.4 (P = 0.03). In order to determine how this adverse effect is mediated, the mean rate of decline in serial CD4+ lymphocyte counts was studied. CD4+ lymphocyte counts tended to decline more rapidly in CMV seropositives than in seronegatives (-0.087 x 10(9)/l per annum versus -0.082 x 10(9)/l per annum), but this difference did not reach statistical significance. The average CD4+ lymphocyte count at the time of HIV seroconversion was estimated to be similar in CMV seropositives and negatives, because in HIV-1-negative haemophiliacs the CD4+ counts were virtually identical, after adjustment for age (0.94 x 10(9)/l and 0.97 x 10(9)/l, respectively). The median CD4+ cell count at which AIDS developed was higher in the CMV-seropositive group (0.07 x 10(9)/l) than in the seronegative group (0.04 x 10(9)/l), but this difference did not reach statistical significance. We conclude from these findings that the adverse effect of CMV is not wholly mediated via a more rapid loss of CD4+ cells. We discuss other processes that may be mediated by CMV, such as a functional deficiency of residual CD4+ cells, or dissemination of HIV in other organs, which may be important in determining the earlier onset of AIDS among CMV-seropositive subjects.     

Comparison of absolute neutrophil to CD4 lymphocyte values as a marker of immunosuppression in cancer patients on cytotoxic chemotherapy

Background

The absolute neutrophil count (ANC) is currently used to assess immune status of patients on cytotoxic therapy. The CD4 lymphocytes have also been shown to be of importance in protection against opportunistic infections. In people of African descent a low baseline ANC has been recorded and the currently accepted neutropaenic threshold may not be appropriate.

Objective

This study was aimed at comparing the change in ANC to CD4 lymphocyte count in adult cancer patients following chemotherapy.

Patients and methods

Eighty chemotherapy-naive patients with various malignancies had their ANC and CD4 lymphocyte counts done at days 0 and 12 of the first cycle of various chemotherapeutic regimens. The paired sample t-test was done to assess the significance between these values. Socio-demographic data was obtained using questionnaires.

Results

ANC and CD4 pre-chemotherapy differed significantly from their post-chemotherapy values (p=0.001) for both parameters). The CD4 count showed significant reduction in patients with Non-Hodgkin''s lymphoma (p=0.043), colorectal carcinoma (p=0.037) and other malignancies (p=0.030), while the ANC did not. Patients who had received COPP for Hodgkin''s lymphoma also had significant CD4 depletion (p=0.037).

Conclusion

The CD4 lymphocyte count may be a more suitable parameter than ANC, for monitoring immuno-depletion in cancer patients on cytotoxic chemotherapy. Further studies are required to validate these findings, especially in the Negroid population.     

胃癌患者PBMCs中CD4+CD25+T细胞体外增殖及对CD4+CD25-T细胞增殖的影响

目的:探讨胃癌患者外周血单个核细胞（PBMCs）中的CD4+CD25+T细胞体外增殖及对CD4+CD25-T细胞增殖的影响。 方法:以免疫磁性分离方法 （MACS）分选出胃癌患者外周血单个核细胞中的CD4+CD25+T及CD4+CD25-T细胞后，用流式细胞仪分析细胞的纯度及活力；再以小鼠抗人CD3单抗、小鼠抗人CD28单抗及rh IL-2作为共刺激因子，观察与CD4+CD25-T细胞共培养时，CD4+CD25+T细胞对CD4+CD25-T细胞增殖的抑制效应。 结果:（1）分选后健康对照组及胃癌患者PBMC 中CD4+CD25+ T细胞纯度分别为83.8%±1.84%、84.13%±2.77％，两者相比，无显著差异（P＞0.05）;(2)经MACS 分选后正常对照组与胃癌患者CD4+CD25+ T细胞活力分别为98.52%±0.72%、97.80%±0.95%，两者相比，无显著差异（P＞0.05）；(3)无论是健康对照还是胃癌患者的CD4+CD25+T均具有明显抑制效应性T细胞如CD4+CD25-T细胞的增殖，随着CD4+CD25+T细胞数的增加，这种抑制增殖的能力也相应增加，当CD4+CD25+∶〖KG-*2〗CD4+CD25-T达 1∶〖KG-*2〗1时，抑制率最大达到50％。 结论:MACS分选法能够分选出高纯度及活力的CD4+CD25+T细胞，分选后CD4+CD25+T细胞在体外均能抑制CD4+CD25-T细胞增殖，且这种抑制效应呈一定效靶比关系。