CD8+ T lymphocytes are recruited to neoplastic cervix

To^liicIV distinguish normal cervical lymphocyte populations from phenotypes recruited to the cervix in response to cervical neoplasia, lymphocytes were isolated from normal and neoplastic cervix. A portion of the cervical transformation zone was obtained from 19 patients with pathologically confirmed cervical intraepithelial neoplasia and from 20 patients with normal cervices undergoing hysterectomy for benign indications. Mononuclear cells were harvested from cervical tissue using a serial, multienzymatic digestion procedure and enriched by density gradient centrifugation. Isolated cell populations were stained with surface marker-specific monoclonal antibodies and analyzed by fluorescent activated cell sorter to determine the percentage of B cells, total T cells, CD4⁺ T cells, CD8⁺ T cells, and natural killer (NK) cells. The distribution of circulating peripheral blood lymphocyte phenotypes was similar for both patients with neoplasia and normal controls. A marked disparity in the proportions of NK cells and T cells was demonstrated among lymphocyte phenotypes infiltrating the cervix. The percentage of CD4⁺ T cells and NK cells was significantly depressed (P=0.04,P=0.03, respectively) in dysplastic tissue as compared to normal cervical tissue. In contrast, the proportion of CD8⁺ T cells was significantly increased in the dysplastic tissue (P=0.0001). Analysis of immunocompetent cells in the circulation appears to have little correlation with immunocytes present in the dysplastic epithelium. The depression in the proportion of CD4⁺ T lymphocytes and NK cells at the cervical squamocolumnar junction reflects a local recruitment of CD8⁺ T cells to the site of neoplasia in the cervix.     

Cell-mediated immunity and biological response modifiers in insulin-dependent diabetes mellitus complicated by end-stage renal disease

Previous studies have shown several immunoregulatory abnormalities in insulin-dependent diabetes mellitus (IDDM). In this report we compared peripheral blood mononuclear cells (PBMC) from patients with IDDM complicated by end-stage renal disease (ESRD) to those from normal subjects and from patients with ESRD of different etiologies for their: natural killer (NK) and antibody-dependent cell-mediated cytotoxic (ADCC) activities; modulation of NK and ADCC activities by biological response modifiers (BRM) including purified human lymphoblastoid interferon, human recombinant alpha-2 interferon, human gamma interferon and human recombinant interleukin 2; proliferative response of T and B lymphocytes to concanavalin A (Con A), phytohemagglutinin and pokeweed mitogen, and ability to produce T-cell growth factor (interleukin 2; IL-2). PBMC of diabetic patients demonstrated significantly lower NK activity than normal and ESRD subjects. Upon treatment with BRM, NK activity was augmented and achieved normal levels. ADCC activity was not different from that of normal controls and exhibited similar increases when stimulated by BRM. The proliferative responses to Con A, phytohemagglutinin and pokeweed mitogen as well as IL-2 production in response to Con A stimulation were significantly lower in the IDDM group. Our results indicated that NK cells from patients with IDDM can respond to IL-2 with enhanced cytotoxicity, and, because activation of resting T cells by mitogenic stimuli depends on the production of IL-2 as well as the appearance of a receptor for IL-2, our finding of low levels of in vitro IL-2 production by PBMC from patients with IDDM may explain the depressed NK activity and the observed poor response to T-cell mitogens.     

Enhancement of natural killer cell activation and antibody-dependent cellular cytotoxicity by interferon-alpha and interleukin-12 in vaginal mucosae Sivmac251-infected Macaca fascicularis

We studied the innate immune system of Cynomolgus monkeys (Macaca fascicularis) experimentally infected via the vaginal mucosae with a virulent simian immunodeficiency virus isolate SIVmac251. Animals were evaluated for their natural killer (NK) cell activity, and for their antibody-dependent cellular cytotoxicity. NK cells from SIVmac251-infected macaques show impaired NK cell activity compared to cells from uninfected animals. Subsequent treatment of NK cells with interferon-a (IFN-alpha) or interleukin-12 (IL-12) alone partially restored the NK activity. However, either treatment of NK cells with both IFN-alpha and IL-12 completely reversed the impairment of cytotoxicity induced by simian immunodeficiency virus (SIV) infection. Incubation of NK cells from infected but not from uninfected monkeys with IFN-alpha and IL-12 for 8 days increased the percentage of CD16+/CD56+ cells twofold to five-fold and enhanced antibody-dependent cellular cytotoxicity (ADCC) activity. Thus IFN-alpha and IL-12 greatly enhance both the NK cell and ADCC activities of peripheral blood cells from SIVmac251-infected animals and increase the number of NK cells in longer term culture. The combined effect of IFN-alpha and IL-12 in enhancing NK cell activity may provide a novel therapeutic approach for the restoration of depressed NK cell activity observed in human immunodeficiency virus (HIV)-infected patients.     

Difference in effect of single immunosuppressive agents (cyclophosphamide, CCNU, 5-FU) on peripheral blood immune cell parameters and central nervous system immunoglobulin synthesis rate in patients with multiple sclerosis.

Cyclophosphamide (CY), 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU) and 5-fluorouracil (5-FU) were given in single course schedules to chronic progressive multiple sclerosis (MS) patients clinically stable for 6 months. The following peripheral immune cellular parameters were measured before, during and after each drug administration: white blood count (WBC), polymorphonuclear count (PMN), lymphocyte count, percentage of T cells, T cell response to phytohaemagglutinin (PHA), percentage of B cells, percentage of cells bearing receptors for the Fc portion of immunoglobulin (% FcR cells), killer (K) cell activity defined by antibody-dependent cellular cytotoxicity (ADCC), and natural killer (NK) cell activity. Central nervous system (CNS) immunoglobulin G (IgG) synthesis was also measured. The patients were followed carefully by both quantitative and qualitative methods for any change in their neurologic condition. Selective reduction in NK activity was observed with CY and 5-FU while no significant alteration was seen in %FcR cells and K activity. CY differed from 5-FU in reducing lymphocyte count and B cell percentage while 5-FU decreased the percentage of T cells. CCNU, but not the other drugs, reduced T cell proliferative response to PHA. In addition, CCNU, which is known to penetrate well into the nervous system, caused a modest reduction in CNS IgG synthesis, while 5-FU had an uncertain effect. Clinically the patients were unchanged or continued to progress in their disability. The results suggest an independence of the CNS immune from the systemic immune system in MS in response to many immunosuppressive drugs.     

Effect of Interleukin (IL)-12 and IL-15 on Activated Natural Killer (ANK) and Antibody-Dependent Cellular Cytotoxicity (ADCC) in HIV Infection

The ability of IL-12 and IL-15 to enhance natural killer (NK) activity and antibody-dependent cellular cytotoxicity (ADCC) of mononuclear cells (MNCs) from HIV⁺ children and their mothers was investigated. MNCs from HIV⁺ patients were deficient in NK and ADCC activity compared to control MNCs against several target cells. Overnight incubation with IL-15 or IL-12 augmented NK activity of MNCs from both patients and controls, and the combination of IL-12 and IL-15 resulted in the greatest enhancement. ADCC in HIV⁺ patients against gp120-coated CEM.NKR cells or chicken erythrocytes could also be enhanced by IL-2 or IL-15 in overnight cultures. Culturing MNCs with either IL-2 or IL-15 for 1 week increased the NK activity in patients to levels of controls treated with these cytokines. However, the response to the combination of IL-12 and IL-15 was less than that to IL-15 alone in 1-week cultures. Culturing MNCs with IL-2 and IL-15 for 1 week also increased the percentage of CD16⁺/CD56⁺ cells in both patients and controls. Thus, IL-15 can restore the deficient NK activity in patients and may be a candidate for immunomodulative therapy in HIV⁺ patients.     

Immunological and Functional Characteristics of Peripheral Blood and Synovial Fluid Lymphocytes from Patients with Rheumatoid Arthritis

Spontaneous (SCMC) and antibody dependent cellular cytotoxicity (ADCC); mitogenic responsiveness (PHA, Con A, PPD, dextran and pokeweed) as well as lymphocyte subpopulations (E-, EA-, EAC-rosettes, S-Ig) were studied simultaneously in peripheral blood (PBL) and synovial fluid lymphocytes (SFL) of fifteen patients with rheumatoid arthritis. Marked differences were observed in the cytotoxic activity of SFL and PBL. Whereas SCMC activity of SFL was always significantly elevated above the cytotoxic levels of PBL, the reverse was true for the ADCC reaction; here, 50% of the patients showed a decreased cytotoxicity of SFL compared to PBL. Synovial fluid neutrophils (SFN) were found to be inactive in both cytotoxic assays. No differences were found in ADCC activity of PBL between normal controls and RA patients. In SCMC assays a significantly increased activity of control PBL was only observed at L/T ratios of 100:1. Overnight incubation of PBL from RA patients and normal controls resulted in a marked decrease in SCMC and, to a smaller extent, in ADCC activity. SFL from three out of four patients lost less SCMC activity after overnight incubation than the corresponding PBL. In one patient even an increased activity in both cytotoxic systems was obtained. Regarding lymphocyte populations, T-cells were significantly decreased in PBL of RA patients. With the exception of a significantly lowered percentage of C3 receptor positive cells in SFL, no significant differences were recorded in the lymphocyte distribution between the patients' PBL and SFL. In the RA patients, the response to T-cell mitogens was significantly depressed in SFL while PPD and pokeweed reactivity was equal to that of PBL.     

慢性髓系白血病患者外周血T淋巴细胞亚群和NK细胞检测的临床意义

目的 研究不同分期慢性髓系白血病患者外周血T淋巴细胞亚群、NK细胞的变化特点,以及应用伊马替尼治疗后获得完全细胞遗传学反应(complete cytogenetic reponse,CCyR)患者淋巴细胞亚群表达情况.方法 选取我院诊治40例慢性髓系白血病患者,其中急变期9例,慢性期31例.采用流式细胞术检测外周血T淋巴细胞亚群、NK细胞水平,并与正常对照组进行比较.结果 初治慢性期、急变期CML患者外周血CD3+、CD4+、CD8+T细胞百分率及CD4+/CD8+比值均低于正常对照组,且急变期CD3+、CD4+T细胞百分率及CD4 +/CD8+比值下降尤为突出(P＜0.01);初治慢性期患者NK细胞百分率与正常对照组相比无差异,而急变期患者低于正常对照组(P＜0.05).与正常组对比,伊马替尼治疗首次获得完全细胞遗传学反应患者仅CD4+T细胞百分率降低,差异具有统计学意义(P＜0.05);但获得完全细胞遗传学反应后应用伊马替尼治疗大于12月患者,CD3+、CD4+T细胞百分率及CD4 +/CD8+比值较正常对照组均有所下降(P＜0.05).与治疗前相比,治疗首次获得完全细胞遗传学反应患者CD3+、CD4+T细胞百分率升高(P＜0.05),而缓解后应用伊马替尼治疗大于12月患者T淋巴细胞亚群无改变(P＞0.05);各组的NK细胞百分比无差异(P＞0.05).初诊CML患者、急变期CD4+/CD8+的比值与BCR-ABLl/ABL1的比值呈负相关.结论 CML患者存在细胞免疫调节功能异常,且机体免疫功能与疾病分期密切相关.伊马替尼治疗初次获得完全细胞遗传学反应患者细胞免疫功能得到改善,但长期应用抑制患者细胞免疫功能.     

宫颈癌患者外周血T淋巴细胞及NK细胞的检测及其临床意义

为探讨宫颈癌患者外周血T淋巴细胞亚群和NK细胞活性检测的临床意义,采用流式细胞仪测定宫颈癌患者外周血T淋巴细胞亚群和NK细胞活性,以正常人作对照分析。结果表明,宫颈癌患者外周血CD3＋、CD3＋CD4＋、NK细胞数量及CD3＋CD4＋/CD3＋CD8＋比值较正常对照组均明显下降（P〈0.05）,而CD3＋CD8＋细胞水平显著升高。外周血T淋巴细胞亚群和NK细胞数量的改变与宫颈癌临床病理分期有关,分期越晚,CD3＋细胞、CD3＋CD4＋细胞、CD3＋CD4＋/CD3＋CD8＋细胞比值及NK细胞数量越低,CD3＋CD8＋细胞水平越高;Ⅰ、Ⅱ期宫颈癌患者与Ⅲ、Ⅳ期患者之间有显著差异（P〈0.05）。实验结果提示,宫颈癌患者细胞免疫功能低下,且临床病理分期越晚,其免疫功能越低,检测T淋巴细胞亚群、NK细胞可用于宫颈癌患者的免疫监测。     

Effect of feeding a diet with half of the recommended levels of all vitamins on the natural and inducible levels of cytotoxic activity in mouse spleen cells.

Groups of 6-week-old female C57Bl/6 mice were fed a normal diet with recommended levels of all vitamins or a vitamin-deficient (VD) diet containing half of the recommended level of each vitamin. At different time periods (1-11 weeks) after the initiation of diets, basal natural killer (NK) activity, interleukin-2 (IL-2) and concanavalin A (Con A)-induced cytotoxic activity, Con A-induced IL-2 production and levels of allospecific cytotoxic T cell activity generated in a mixed lymphocyte culture (MLC), were studied in spleen cells derived from control and VD mice. Results indicated that: (i) spleen NK activity remained normal until 2 weeks after the initiation of VD diet, fell steeply to low levels at the 4 and 5 week time points and remained depressed thereafter; (ii) IL-2- and Con A-induced levels of cytotoxic activity in spleen cells derived from VD mice declined at 4 weeks after the institution of VD diet, and then remained low throughout the study; (iii) the capacity of spleen cells from VD mice to generate IL-2 in response to Con A and cytotoxic T cells in response to allogeneic spleen cells, was normal at 1 and 4 weeks after initiation of the VD diet and was markedly depressed at the 6 and 9 week time points. These results suggest that partial combined deficiencies of dietary vitamins strongly influence assays of immune function.     

Immune functions in inflammatory bowel and coeliac diseases

Different immune functions of 10 patients with glutein-sensitive enteropathy (GSE), 9 with Crohn's disease (CD), 11 with ulcerative colitis (UC) and 13 healthy controls were characterized. The numbers of suppressor T cells in GSE were comparable to those of the controls; otherwise, the lymphocyte subpopulations were decreased in these bowel diseases. In the whole-blood cultures, the lymphocyte proliferative responses to PHA were normal in the bowel diseases, but the responses to Con A were decreased in CD. In cultures with D-penicillamine, the inhibition of the helper effect of CD patients was more pronounced in PHA-stimulated cultures than in Con A-stimulated cultures. The total Ig and IgA production did not markedly differ among the groups. PWM-induced IgM secretion was significantly decreased in GSE, CD and UC, and IgG secretion in CD and UC, as compared to controls. In GSE, an increased Con A inducible suppressor cell activity was observed in the IgM production. Altogether, no clear-cut immunological imbalance was detected in any of the bowel diseases; this in agreement with previous works. However, there are some differences in the regulatory cell balance among the patients with GSE, CD and UC. The determination of lymphocyte proliferative responses to PHA and Con A together with D-penicillamine seems to provide a new immunological criterium for distinguishing between Chrohn's disease and ulcerative colitis.     

T-cell abnormality and defective interleukin-2 production in patients with carcinoma of the urinary bladder with schistosomiasis

Patients with schistosomiasis of the urinary bladder (SB) and schistosomiasis with carcinoma of the urinary bladder (SCB) had significantly increased percentage of IL-2R-, HLA-DR-, and transferrin receptor (T9)-bearing T cells in circulation. The percentage of these activated T cells decreased byin vitro culture with PHA but increased bySchistosoma haematobium soluble egg antigen. These patients with SB and SCB had a PHA-specific defect in IL-2 production. A functional defect with induction of IL-2R-positive suppressor monocytes appears to correlate with the defective PHA-induced IL-2 production by CD4+ T cells and monocytes. Disordered regulation of PHA-induced IL-2 production by the CD4+ T cells and monocytes may be the key feature in the highly depressed cell-mediated immune response in schistosomiasis. However, immune activation and significantly elevated IL-2 production in response to disease-specificS. haematobium soluble egg antigen may be related with the pathogenesis of SB and SCB. Thus,S. haematobium-specific CD4+ T cells are present in schistosomiasis, and their function is determined by adequate release of IL-2-and/or IL-2R-bearing CD11+ suppressor monocytes.     

Kinetic studies of the immunopharmacologic effects of NPT 15392 in mice

NPT 15392 [9-erythro-(2-hydroxy,3-nonyl)-hypoxanthine] was administered in a single intraperitoneal injection to Balb/c mice at a dose of 0.1 mg/kg. Modifications of immune parameters were evaluated 1-14 days after the treatment. NPT 15392 potentiated antibody responses to both T-dependent (SRBC, TNP-KLH) and T-independent (TNP-LPS) antigens and delayed-type hypersensitivity to oxazolone. The proliferative response of spleen cells from NPT-treated mice to stimulation with PHA was depressed, but that to dextran sulphate was augmented. The responses to Con A or LPS were inconsistently modified. NPT 15392 augmented killer cell functions, including both T cell-mediated cytotoxicity against allogeneic tumor cells and NK cell activity against YAC-1 tumor cells. It slightly augmented or depressed ADCC activity against antibody-coated chicken erythrocytes (CRBC) depending on the time of its administration. Concerning the stimulation of NK cell activity, the effect was more marked on spleen effector cells when NPT 15392 was given i.v. and on peritoneal effector cells when it was given i.p. From these results, T helper cells, B cells, and NK cells appeared to be target cells of NPT 15392 action. The various stimulatory effects peaked at different times according to the immune function tested. In addition, the prolonged, sometimes double-peaked action (antibody response to T-dependent antigens, NK activity) indicates complex mechanisms of action which may involve indirect interactions mediated by lymphokines or monokines.     

Soluble and cellular markers of immune activation in patients with systemic sclerosis

The peripheral blood lymphocyte pattern, the lymphocyte responses in vitro, as well as the soluble markers of immune activation were studied in 24 patients with systemic sclerosis (SSc patients). The proportions of total T cells (CD3), their CD4 subset, as well as B lymphocytes were within the normal range. The relative proportion of CD8 lymphocytes, however, was significantly reduced. Patients with SSc had a slightly lower percentage of CD4/4B4+ cells, whereas their proportion of CD4/2H4+ cells was elevated as compared to healthy controls. The proportion of lymphocytes expressing the interleukin-2 receptor (IL-2R) was significantly higher in SSc patients. The proliferative responses of peripheral blood mononuclear cells to PHA stimulation were reduced in the patient group, while expression of IL-2R on lymphocytes after such in vitro stimulation was comparable to that of controls. Expression of IL-2R on patient but not control lymphocytes was increased after in vitro exposure to laminin. Such exposure failed to induce IL-2 production or cell proliferative responses. Soluble plasma IL-2R level (sIL-2R) and soluble CD8 (sCD8) molecule levels in SSc patients were significantly elevated. These results indicate the presence of an ongoing lymphocyte activation in this disease process.     

Relationship between intensity of infection and immunomodulation in human schistosomiasis. II. NK cell activity and in vitro lymphocyte proliferation.

Natural killer (NK) cell activity against K-562 targets and lymphoproliferative responses to Con A, interleukin-2 (IL-2) and Con A + IL-2 were examined in a group of 41 Sudanese children suffering from schistosomiasis mansoni and haematobium. The results were correlated to the intensity of infection as determined by enumeration of parasite ova in urine and stool. NK cell activity measured at three effector to target cell ratios was significantly depressed in the patient group as compared to a German control group. Impairment of NK cell activity showed a direct relationship with the patients' parasite load. Furthermore lymphoproliferation to Con A, IL-2 and Con A + IL-2 was depressed in the group of patients. Interestingly the costimulation effect of IL-2 expressed as coefficient of delta ct/min(Con A + IL-2)/delta ct/minCon A correlated significantly to the intensity of infection suggesting that lymphocytes from heavily infected patients were defective in producing appropriate amounts of IL-2 in response to Con A. Our findings support the concept that heavy infections with S. mansoni and/or S. haematobium induce a peculiar dichotomy of cellular and humoral immune parameters. Whereas T cell-dependent cellular immune responsiveness and NK cell function decrease with increasing worm burden specific IgE and IgG antibody responses increase.     

胃癌患者红细胞C3b受体与淋巴细胞免疫功能的相关性研究

目的：研究胃癌患者红细胞C3b受体（RBC-C3bR）与淋巴细胞免疫功之间的关系。方法：利用酵母菌花环试验、MTT法及克隆抗体致敏花环法对51例胃癌患者及30例正常人的RBC-C3bR、自然杀伤细胞（NK）活性及T淋巴细胞（TC）亚群进行测定。结果：胃癌患者RBC-C3bR阳性率、NK细胞杀伤活性、CD3^＋、CD4^＋、CD4^＋／CD8^＋比值均比正常对照组显著低下（P〈0．05、P〈0．01）。经统计学相关性分析显示，RBC-C3bR阳性率与CD4^＋／CD8^＋比值、NK细胞杀伤活性间呈正相关（P〈0．05，P〈0．01）。结论：胃癌患者红细胞免疫功能与淋巴细胞免疫功能一样受到抑制，二者免疫功能密切联系、相互影响。     

Effect of lymphokines on natural killer cytotoxicity in patients with high risk of developing the acquired immune deficiency syndrome

Regulation of natural killer (NK) activity of peripheral blood mononuclear cells (PBMC) from patients with the acquired immune deficiency syndrome (AIDS) and from individuals at high risk of developing AIDS (R-AIDS) was studied. The response of untreated PBMC to the interferon inducer polyinosinic polycytidilic acid (Poly I:C) was lower in AIDS and R-AIDS than in normal controls and PBMC from R-AIDS were more susceptible to stimulation with lymphokine rich supernatants (Con A-SN, PHA-SN, lectin free IL-2) than AIDS and normal controls. To determine the role of the different T lymphocyte subsets in the regulation of NK activity, PBMC were selectively treated with monoclonal non-cytotoxic anti-Leu 2a and anti-Leu 3a antibodies and then stimulated with lymphokine rich supernatants. These results indicate that the effect of crude supernatants was the combination of opposite effects. Leu 2a-blocked R-AIDS-PBMC enhanced NK cytotoxicity when exposed to IL-2 rich supernatants whereas Leu 3a-blocked R-AIDS-PBMC suppressed the cytotoxic reaction.     

In vivo effect of isoprinosine on interleukin-2 production, lymphocyte mitogenesis and NK activity in normal and cyclophosphamide immunosuppressed mice

The in vivo effect of isoprinosine on IL-2 production, mitogen-induced proliferation and NK activity of lymphocytes from normal as well as cyclophosphamide (CY) treated mice has been investigated. Isoprinosine was given in a single dose (50 mg/kg or 5 mg/kg) to normal or CY treated mice (250 mg/kg i.p. simultaneously to isoprinosine). An enhancement of T lymphocyte proliferation and IL-2 production was observed in both cases. There was no correlation between the small effect observed in T lymphocyte proliferation and the enhancement of IL-2 levels found in the supernatants of Con A activated spleen cells, specially in normal mice. Administration of isoprinosine every day (50 mg/kg) augmented Con A induced mitogenesis, IL-2 production and NK activity in animals treated with cyclophosphamide, but not in normal mice. Isoprinosine could be of interest in a combined treatment with immunosuppressants for the restoration of certain immune functions. The effect of isoprinosine on immune responses may be mediated in part by changes in IL-2 activity.     

宫颈癌患者HPV感染和调节性T细胞的相关性研究

目的 探讨宫颈部位人乳头瘤病毒（HPV）感染与CD4＋ CD25＋ CD127-调节性T细胞（TReg）及机体免疫水平的关系.方法 采用第二代核酸杂交扩增技术（HC2）检测41例正常对照组、50例宫颈上皮内瘤变（CIN）Ⅰ、42例CIN Ⅱ～Ⅲ和70例感染HPV宫颈癌患者;采用流式细胞术检测外周血CD4＋CD25＋ CD127-TReg、细胞毒性T细胞（CTL）和NK百分率;采用酶联免疫吸附实验（ELISA）检测血清中TGF-β1和INF-γ的含量.结果 ①HPV感染率随着宫颈病变的加重而升高（P =5.75×10^-19）;②宫颈CIN Ⅱ～Ⅲ组与宫颈癌组外周血CD4＋CD25＋CD127-TReg、CTL、NK、TGF-β1、INF-γ与CIN Ⅰ组及正常对照组比较,差异均 有统计学意义（P=1.03×10^-9）;且在HPV阴阳性组间比较亦有统计学意义（P=2.33×10^-4）;③CTL与NK和Treg呈负相关（P值分别为1.62×10^-6和3.41×10^-5）;INF-γ含量与TReg呈负相关（P=2.11×10^-5）;④HPV与CD4＋ CD25＋ CD127-TReg百分率呈正相关（P =3.02×10^-6）.结论 宫颈HPV感染与TReg密切相关,TReg失调导致的免疫水平下降可能是宫颈癌免疫逃避机制之一.     

Effect of phorbol myristate acetate on T cell colony formation, interleukin-2 (IL-2) receptor expression and IL-2 production by cells from patients at all stages of HIV infection.

We and others have shown that several T cell responses induced by the mitogen phytohaemagglutinin (PHA), including T cell colony formation, IL-2 receptor (IL-2R) expression, and IL-2 production are impaired in patients with AIDS and lymphadenopathy syndrome (LAS). We investigated whether phorbol myristate acetate (PMA) could act in synergy with PHA (as it does in healthy subjects) to enhance in vitro T cell responses of patients at all stages of infection by HIV. In AIDS patients with opportunistic infections (AIDS/OI), PHA + IL-2 + PMA led to a total disappearance of T cell colonies in 10/11 patients, among whom six already displayed very low numbers of colonies induced by PHA + IL-2 (less than 50 colonies/5 x 10(4) cells). In contrast, T cell colony formation induced by PHA + IL-2 + PMA was maintained or increased, compared with that induced by PHA + IL-2, in five out of six AIDS patients with Kaposi's sarcoma (AIDS/KS), 10/14 LAS and six out of seven HIV-seropositive asymptomatic (HIV+/AS) homosexuals. In these three groups of patients, a low percentage of colony cells induced by PHA + IL-2 + PMA expressed CD3 and CD4 molecules, but 50-89% of cells were IL-2R (Tac) positive, as in healthy controls. Studies on T cell activation and IL-2 production were performed on a selected group of 12 HIV-infected patients for whom sufficient numbers of lymphocytes could be obtained. PMA induced CD4 down-modulation in controls and in HIV-infected patients. However, CD3 down-modulation and induction of the Tac chain of IL-2R by PMA were significantly impaired in patients, compared with controls, and these two parameters were correlated. Although PHA alone induced virtually normal levels of Tac antigen on patients' cells, Tac induction by PHA + PMA was significantly decreased in patients versus controls. Cells from five out of 10 patients tested failed to produce detectable amounts of IL-2 after PHA stimulation, whereas IL-2 production increased significantly in all patients tested (n = 9) after PHA + PMA, with a level of IL-2 activity significantly higher than in controls. No correlation was found in this group of patients between the effects of PMA + PHA on T cell colony formation, Tac expression, or IL-2 production, as compared with PHA alone. Taken together, our results indicate that in vitro T cell functional studies with PMA may be useful to evaluate better the defects of T cell activation in HIV-infected patients.     

Analysis of CD16+dim and CD16+bright lymphocytes--comparison of peripheral and clonal non-MHC-restricted T cells and NK cells.

The Fc gamma RIII receptor (CD16) has been described on natural killer cells and a small subset of T lymphocytes. CD16+bright lymphocytes represent the typical population of peripheral blood CD3- NK cells. In these studies in addition to CD16+bright NK cells Fc gamma RIII expressing cytotoxic T lymphocytes in peripheral blood from one healthy individual are characterized as CD16+dim non-MHC-restricted CTLs either expressing the alpha/beta (80%) or the gamma/delta T cell receptor (20%). Both CD16+ subsets are clearly distinct in their functional capacity performing NK and ADCC activity. Freshly isolated CD16+dim T cells exert higher ADCC, CD16+bright NK cells higher NK activity. They are also differentially activated by interleukin-2 since CD16+bright NK cells reveal a bright expression of the p75 IL-2 receptor beta-chain in contrast to the very low p75 expression on CD16+dim T cells. This activation leads to a gradual increase of ADCC by NK cells. Finally the CD16 expression pattern with low and bright intensity represents a stable phenotype expressed by clones generated from these different subpopulations. On a clonal level CD16+dim non-MHC-restricted T cells can be distinguished from CD16+bright NK cells by their lower capacity in NK killing, but they are equally potent in ADCC. Finally these CD3+CD16+dim clones provide the basis for studies of Fc gamma RIII and TcR interaction.