Natural Killer Cell Cytotoxicity and Antibody-Dependent Cellular Cytotoxicity to Herpes Simplex Virus-Infected Cells in Human Pregnancy

ABSTRACT: Natural killer cell (NKC) cytotoxicity and antibody-dependent cellular cytotoxicity (ADCC) represent the ability of human leukocyte effector cells to destroy target cells in the absence and presence of antibody, respectively. Since these immune systems play a pivotal role in the body's primary lines of defense against a variety of pathogens including herpes simplex virus (HSV), a study was undertaken to evaluate the influence of pregnancy on these systems. Eleven uncomplicated gravidas were followed serially through each trimester and compared to 11 nonpregnant female controls. Mononuclear cells were acquired by Ficoll-Hypaque centrifugation of heparinized blood. Chang liver cells infected with HSV-I were utilized as target cells in a ⁵¹Cr release assay. Mean NKC values in the pregnant patients were uniformly lower than in the controls. No similar decreases in ADCC activity were observed in a comparison between the two study populations. These data support previous observations suggesting that pregnancy represents a relatively immunocompromised state. Differences apparently exist between NKC and ADCC effector cell populations with regard to the influence of pregnancy. Although these physiologic alterations in immunoregulation may help support the fetoplacental allograph, detrimental conditions may exist regarding susceptibility to various pathogens such as HSV.     

Natural Killer Cytotoxicity and Antibody-Dependent Cell Cytotoxicity to Herpes Simplex Virus-Infected Target Cells in Murine Pregnancy

ABSTRACT: In vitro natural killer cytotoxicity (NKC) and antibody-dependent cell cytotoxicity (ADCC) activity against herpes simplex virus (HSV)-infected cells were evaluated in a pregnant murine model (C₅₇B1₆inbred strain). Virgin (n = 16) and pregnant (late gestation) mice (n = 15) were infected intraperitoneally with HSV, type 1. After 18 hr, a 0.5-ml aliquot of the peritoneal wash was frozen for virus plaque assay, and the cells were cultured in the ⁵¹chromium release assay for NKC and ADCC. %NKC (mean ± S.E.) to HSV-infected targets was significantly suppressed (P < 0.05) in pregnant mice, 10.3% ± 1.9, compared to that of virgin mice, 32.5% ± 2.5. This suppression was abrogated with HSV-specific antisera (%ADCC); 53.9% ± 4.4 (pregnant) compared to 49.1% ± 3.6 (virgin). The diminished NKC activity in pregnant mice was reflected in an increased mean number of virus particles in the peritoneal wash, 266 + 66 PFU/ml, compared to 38 ± 11 PFU/ml in virgin mice (P < 0.05). We concluded that NKC, but not ADCC, to HSV-infected targets was suppressed and that HSV elimination was impaired in pregnant mice.     

Effect of vernolide-A,a sesquiterpene lactone from Vernonia cinerea L., on cell-mediated immune response in B16F-10 metastatic melanoma-bearing mice

One of the major reasons for the rapid progression of cancers is the ability of tumor cells to escape from the immune surveillance mechanism of the body. Modulation of immune responses is highly relevant in tumor cell destruction. Effect of vernolide-A on the cell-mediated immune (CMI) response in metastatic condition was studied using C57BL/6 mice model. Administration of vernolide-A enhanced natural killer (NK) cell activity, antibody-dependent cellular cytotoxicity (ADCC), and antibody-dependent complement-mediated cytotoxicity (ACC) and the activity was observed in treated group much earlier compared with the metastatic tumor-bearing control. Administration of vernolide-A significantly enhanced the production of interleukin (IL)-2 and interferon-gamma (IFN-γ) in metastatic tumor-bearing animals. In addition, vernolide-A significantly down-regulated the serum levels of proinflammatory cytokines such as IL-1β, IL-6, tumor necrosis factor-alpha (TNF-α), and granulocyte–macrophage colony-stimulating factor (GM-CSF) during metastasis. All these results demonstrate that vernolide-A could enhance the immune response against metastatic progression of B16F-10 melanoma cells in mice.     

Evidence for a Correlation Between Antibody-Dependent Cellular Cytotoxicity-Mediating Anti-HIV-1 Antibodies and Prognostic Predictors of HIV Infection

Using our gp120/41-expressing, NK cell activity-resistant CEM.NK^R cell clones as targets in HIV-1-specific antibody-dependent cellular cytotoxicity (ADCC) assays, we demonstrate here that the serum titers of anti-HIV-1 ADCC antibodies bear a significant (P < 0.05) positive correlation with the peripheral blood CD4+ T cell counts and a negative one with the number of copies of HIV-1 RNA in the plasma of HIV-infected individuals. These findings underscore the importance of these antibodies as a protective immune parameter in these infections.     

Alveolar macrophage interleukin (IL)-10 and IL-12 production in atopic asthma

Inflammation in asthma is characterized by a Th2 response. In many experimental systems, this response can be regulated by interleukin (IL)-IO and IL-12. IL-10 deactivates T cells, and IL-12 reorients the response toward a Till pattern. Alveolar macrophages (AM) can secrete both of these cytokines, and thus regulate T-cell behavior in asthma. They can enhance the Tli2 response by turning off their secretion of IL-10 and IL-12. or tend to downregulate it by producing these cytokines. To elucidate that point, we assayed the AM IL-10 and IL-12 from 11 asthmatic patients and four controls. Six asthmatics were treated by inhaled corticosteroids. AM were recovered by bronchoalveolar lavage (BAL). They were isolated and cultured for 24 h without stimulation or in the presence of lipopolysaccharide (LPS), IL-10 and the p40 subunit of IL-12 were assayed in the BAL fluid and i n AM culture supernatants by ELISA. Spontaneous AM IL-10 production was higher in asthmatics, particularly in the treated group. The AM IL-10 production after stimulation by LPS was also elevated in asthmatics, but was mainly so in untreated patients. IL-12 levels were higher in BAL fluids from untreated patients than from controls. The IL-12 production of LPS-stitnulated-AM from these patients was increased. These results show that AM are at least primed for the production of IL-10 and IL-12 in asthma, and suggest that these cells could be involved in the resolution of the asthmatic inflammation.     

Interleukin (IL)-4 promotes T helper type 2-biased natural killer T (NKT) cell expansion, which is regulated by NKT cell-derived interferon-gamma and IL-4

CD1d-restricted natural killer T (NKT) cells can rapidly produce T helper type 1 (Th1) and Th2 cytokines and also play regulatory or pathological roles in immune responses. NKT cells are able to expand when cultured with alpha-galactosylceramide (alpha-GalCer) and interleukin (IL)-2 in a CD1d-restricted manner. However, the expansion ratio of human NKT cells is variable from sample to sample. In this study, we sought to determine what factor or factors are responsible for efficient in vitro expansion of NKT cells from various inbred mouse strains. Although the proportion of NKT cells in the spleen was nearly identical in each mouse strain, the growth rates of NKT cells cultured in vitro with alpha-GalCer and IL-2 were highly variable. NKT cells from the B6C3F1 and BDF1 mouse strains expanded more than 20-fold after 4 days in culture. In contrast, NKT cells from the strain C3H/HeN did not proliferate at all. We found that cell expansion efficiency correlated with the level of IL-4 detectable in the supernatant after culture. Furthermore, we found that exogenous IL-4 augmented NKT cell proliferation early in the culture period, whereas interferon (IFN)-gamma tended to inhibit NKT cell proliferation. Thus, the ratio of production of IL-4 and IFN-gamma was important for NKT cell expansion but the absolute levels of these cytokines did not affect expansion. This finding suggests that effective expansion of NKT cells requires Th2-biased culture conditions.     

Natural killer (NK) and antibody-dependent cellular cytotoxicity (ADCC) activities can be differentiated by their different sensitivities to interferon and prostaglandin E1

Though purported to be identical cells (or in identical populations of cells), the natural killer (NK) cell mediating spontaneous natural cytotoxicity and the killer (K) cell mediating antibody-dependent cellular cytotoxicity (ADCC) may not be totally identical, at least in susceptibility to regulation by the immunomodulators prostaglandin E₁ (PGE₁) and interferon (IFN). We demonstrate here that NK cells are always enhanced by IFN, while K cells are inhibited from binding targets, resulting in fewer effectors at optimal concentrations of antibody. Only at 10- to 100-fold suboptimal concentrations of antibody is ADCC activity enhanced. As measured by magnitude of inhibition and dose-response titration, ADCC activity is less sensitive to the effects of PGE₁ than is NK activity in the⁵¹Cr release assay and single-cell assay. After overnight incubation with or without PGE₁, whatever sensitivity ADCC activity had to PGE₁ is lost. However, NK cells incubated in the presence of PGE₁ overnight are still sensitive to inhibition. Indomethacin boosts NK activity without having any effect on ADCC activity. Finally, NK activity is substantially reduced by overnight incubation of cells at room temperature, which has no effect on K cells.     

Granulocyte colony stimulation factor (G-CSF) suppresses interleukin (IL)-12 and/or IL-2 induced interferon (IFN)-gamma production and cytotoxicity of decidual mononuclear cells

PROBLEM: The placenta is one of the few non-hematopoietic tissues to express granulocyte colony stimulation factor (G-CSF). Placental G-CSF production is considered to be one of the major causes of granulocytosis during pregnancy although its physiological role in pregnancy has not yet been examined. METHOD OF STUDY: The effects of G-CSF on interleukin (IL)-2 and/or IL-12 induced interferon (IFN)-gamma production of magnetic cell sorting (MACS) sorted decidual lymphocytes was examined by enzyme-linked immunosorbent spot-forming cell assay (ELISPOT). The effect of G-CSF on cytotoxicity of decidual lymphocytes against the choriocarcinoma cell line JEG-3 was examined by lactate dehydrogenase (LDH) release assay. RESULTS: As previously reported by us, IL-2 and/or IL-12 activated decidual mononuclear cells were capable of killing choriocarcinoma cells. We observed that G-CSF abolished IFN-gamma production and cytotoxicity of decidual mononuclear cells and MACS sorted CD56+ cells. CONCLUSIONS: In addition to its well-known trophic effects on hematopoiesis, our results suggest about new roles of G-CSF in reproductive immunology.     

过敏性紫癜患儿血清IL-8和IL-12的水平及其意义

目的:旨在探讨IL-8和IL-12在AP和在APN发病机制中的作用及其相互关系,期望在AP的治疗方面提供一些新的理论依据。方法:检测32例AP、11例APN和15例正常儿童血清中IL-8、IL-12的变化,并分析它们之间的相关性意义。结果:过敏性紫癜患儿急性期血清中IL-8、IL-12的含量无论普通组还是肾损害组均显著高于对照组,恢复期IL-8和IL-12仍高于正常对照组。急性期IL-8和IL-12呈正相关性。说明二者共同参与了过敏性紫癜的发病过程。结论:本实验说明了IL-8和IL-12共同参与了过敏性紫癜的发病过程,尤其在紫癜性肾炎中,为IL-8、IL-12拮抗剂在过敏性紫癜治疗中的应用提供了客观依据。     

Expression of interleukin (IL)-12 (p40) and IL-12 (β2) receptors in allergic rhinitis and chronic sinusitis

BACKGROUND: Interleukin (IL)-12 is a relatively new and structurally distinct TH1-associated cytokine produced by B cells and macrophages, which may play a suppressive role in the development of allergic sinonasal mucosal responses. OBJECTIVE: We investigated the expression of IL-12 (inducible p40 subunit) and its receptor (IL-12R beta2 subunit) in tissue biopsies of naturally exposed patients with allergy-associated (ACS) and nonallergy-associated chronic sinusitis (NCS) and compared it with controls. We also examined IL-12 and IL-12R expression in biopsies from a ragweed allergen challenge model. In the allergen challenge model, the effect of pretreatment with topical corticosteroids on IL-12 and IL-12R expression was assessed. METHODS: To detect IL-12 and IL-12R mRNA, we employed the technique of in situ hybridization using digoxigenin-labelled riboprobes. RESULTS: In both ACS and NCS subjects there was decreased expression of IL-12 as compared with control (P < 0.05). IL-12R (beta2) expression was decreased in ACS subjects as compared with control (P < 0.05), however, there was no significant difference found between NCS subjects and control. In the allergen challenge subjects, there was a significant decrease in IL-12 expression following challenge (P < 0.05). This effect was abrogated by pretreatment of the subjects with topical corticosteroids. However, IL-12R (beta2) expression showed no change following allergen challenge while pretreatment with topical corticosteroids resulted in increased expression of the (beta2) receptor after allergen challenge (P < 0.05). CONCLUSION: Our data suggest that IL-12 plays a role in the in vivo suppression of the allergic inflammatory response and that the control of this suppression may be exerted largely via the IL-12 (beta2) receptor.     

Antibody-dependent cellular cytotoxicity (ADCC)-mediated destruction of human immunodeficiency virus (HIV)-coated CD4+ T lymphocytes by acquired immunodeficiency syndrome (AIDS) effector cells

The acquired immunodeficiency syndrome (AIDS) is defined in clinical terms by the development of Kaposi's sarcoma and/or severe opportunistic infections in persons without predisposing conditions. A hallmark of the syndrome has been a decrease in the number of CD4⁺ T helper cells. The reduction in the frequency of the CD4⁺ lymphocytes has been postulated to be primarily the result of human immunodeficiency virus (HIV) tropism and cytophathogenicity for the T-cell subset. Yet only a small percentage of cells is actually infected with HIV. Recently, we provided evidence indicating that AIDS patients' natural killer cells can mediate normal levels of antibody-dependent cellular cytotoxicity (ADCC) despite exhibiting a defect in natural killer (NK) effector function (J Immunol 139:55, 1987). This finding prompted us to investigate whether AIDS patients' effector cells could mediate ADCC against circulating CD4⁺ T cells infected with or expressing HIV antigen. The findings reported herein demonstrate that AIDS effector cells can mediate lysis of CEM (CD4⁺ T-cell line) coated with HIV protein in the presence of HIV-specific antibody. Lysis was specific, as non-HIV-coated CEM or the addition of HIV-negative serum resulted in no lysis. We then examined HIV-coated peripheral blood-derived CD4⁺ T lymphocytes as targets in ADCC. We demonstrate that in the presence of HIV-specific antibody, HIV-coated CD4⁺ T lymphocytes serve as targets for ADCC by AIDS effector cells. The lytic activity obtained with AIDS effector cells was comparable to that obtained with normal effector cells. These results demonstrate that AIDS effector cells can mediate ADCC against HIV-coated CD4⁺ T lymphocytes and suggest that ADCC may play a rolein vivo in the pathogenesis of AIDS.     

Are Granulocytes the Main Effector Cells of Natural Cytotoxicity in Chickens?

Purified peripheral blood granulocytes from chicken were tested for cytotoxic activity against two types of virus-transformed chicken cell line, LSCC-H32 and LSCC-RP9. Strong cytotoxicity could be demonstrated, as measured in a 4-hr 51Cr-release assay, especially against the fibroblastoid LSCC-H32 cells. The degree of cytotoxicity was dependent on the E:T ratio. Normal CEF cells were completely resistant to the cytotoxicity. No cytotoxicity of human granulocytes could be observed against a variety of adherent and non-adherent target cells, as measured by the same microcytotoxicity technique. The priority of granulocytes in the natural cytotoxicity in the avian system is, therefore, suggested.     

Interleukin (IL)-2 and IL-12 responses to Chlamydia trachomatis infection in adolescents

Chlamydia trachomatis infects epithelial cells at the mucosal surface. While in vitro and animal studies have shown changes in mucosal T(H)1-associated cytokines in the presence of C. trachomatis infection and with its progression to the upper genital tract or clearance, in vivo cytokine responses to chlamydial infection in humans are not well understood. Using a quantitative enzyme-linked immunosorbent assay (ELISA), we examined the endocervical production of two T(H)1-associated cytokines, i.e. interleukin (IL)-2 and IL-12, in relation to C. trachomatis infection in adolescents. At a randomly selected visit for 396 females, median endocervical IL-2 levels were significantly lower (190 versus 283 pg/ml, P = 0.02) and median IL-12 levels significantly higher (307 versus 132 pg/ml, P < 0.001) in subjects testing positive versus negative for C. trachomatis. These divergent T(H)1-associated cytokine responses were: (1) confirmed in paired analyses of 96 individuals before and after infection within 6-month intervals, (2) reversible in 97 patients who cleared infection during consecutive visits, (3) not attributable to sociodemographic factors or other genital infections and (4) independent of common genetic variants at the IL2 and IL12B loci associated previously with differential gene expression. From these findings we infer that increased IL-12 and decreased IL-2, observed commonly during mucosal inflammation, are important features of mucosal immune defence against C. trachomatis infection.     

Human Immunodeficiency Virus (HIV) Type-1 GP120-Specific Cell-Mediated Cytotoxicity (CMC) and Natural Killer (NK) Activity in HIV-Infected (HIV+) Subjects: Enhancement with Interleukin-2(IL-2), IL-12, and IL-15

Cell-mediated cytotoxicity (CMC), as mediated by cytophilic antibody to human immunodeficiency virus (HIV) antigens, may be an important defense in HIV-infected (HIV⁺) patients in response to the virus. In this study the ability of interleukin (IL)-2, IL-12, and IL-15 to enhance natural killer (NK) and gp120-specific CMC of mononuclear cells (MNCs) from HIV⁺children and adults was examined. NK activity against K562 cells was deficient in HIV⁺patients compared to controls and could be enhanced by IL-2, IL-12, or IL-15, with the combinations of IL-2 + IL-12 and IL-12 + IL-15 producing more cytotoxicity than individual cytokines. Gp120-specific CMC was significantly higher in patients than in controls. It could be increased by IL-2, IL-12, and IL-15 and further by combining IL-2 and IL-12. When an exogenous source of antibody in the form of hyperimmune HIV-specific immunoglobulin (HIVIG) was present, the response of control MNCs was much higher than that of patients, although gp120-specific cytotoxicity of patients’ MNCs was significantly enhanced (two- to threefold) by the addition of HIVIG. This increment in cytotoxicity due to HIVIG, however, could not be further augmented by cytokines in controls or patients. Our findings suggest multiple cytokine administration to boost NK cell function, together with passive immunotherapy, might offer a new therapeutic approach to benefit HIV⁺patients.     

IL-12p70、p40在子宫内膜异位症患者腹腔液中的表达及意义

目的　通过测定子宫内膜异位症患者腹腔液中IL - 12 p70及IL - 12p4 0的水平 ,探讨其与子宫内膜异位症发生发展的关系。方法　采用酶联免疫吸附法 (ELISA)测定 2 0例子宫内膜异位症患者 (内异症组 )及 2 0例卵巢良性肿瘤患者(对照组 )腹腔液中IL - 12p70、IL - 12 p4 0的水平。比较两组间两个细胞因子水平以探讨它们与内异症发生的关系 ,并探讨其是否与疾病的进展有关。结果　腹腔液中IL - 12 p70水平内异症组稍低于对照组 ,但两者之间差异无显著性 (P >0 0 5 ) ;IL- 12 p4 0水平内异症组明显高于对照组 ,差异有显著性 (P <0 0 5 ) ;内异症组中 (Ⅰ～Ⅱ期 )患者IL - 12 p4 0水平较 (Ⅲ～Ⅳ期 )患者稍高 ,但两者差异并无显著性 (P >0 0 5 ) ;而 (Ⅰ～Ⅱ期 )患者IL - 12 p70水平明显高于 (Ⅲ～Ⅳ期 )患者 ,差异有显著性 (P <0 0 5 )。结论　内异症患者腹腔液中IL - 12p4 0水平的增高可能是自然杀伤 (NK)细胞功能受损的部分原因 ,从而可能与子宫内膜异位症的发生有一定关系 ;腹腔液中IL - 12 p70水平随内异症疾病程度进展而下降 ,表明其可能是内异症中NK细胞功能进一步下降的原因之一 ,从而可能是促使内异症进一步发展的原因之一。     

Characterization of the in vivo and in vitro Effects of Indomethacin on Human Natural Killer Cell Activity

The in vivo and in vitro effects of indomethacin on the natural killer (NK) cell activity against K 562 target cells were studied. In vivo administration of indomethacin, 3 X 50 mg for 7 days to normal donors did not influence baseline NK cell activity, which means that treatment with prostaglandin (PG) inhibitors can be allowed in studies on NK cell activity of persons with normal PG production. The NK cell activity of fresh mononuclear cells was boosted with pharmacological concentrations of indomethacin in vitro, while frozen cells were not. Our results indicate that indomethacin enhances the NK cell activity in vitro by blocking the prostaglandin production of monocytes, since monocyte depleted effector cells were not boosted by indomethacin.     

The combined effect of interleukin (IL)-10 and IL-12 polymorphisms on induced cytokine production

Interleukin (IL)-12 and IL-10 are immunoregulatory cytokines with an antagonistic effect of the T-helper (Th)1/Th2 cytokine balance and provide a functional link between innate and adaptive immune responses. The aim of the study was to investigate the combined effect of -1082A*G in IL10 and +16974A*C in IL12B single nucleotide polymorphisms (SNPs) on induced cytokine production by stimulated peripheral blood mononuclear cells (PBMCs) isolated from healthy donors. The presence of the high-producer IL-12p40 genotype led to diminished production of IL-10 as determined by the -1082*G allele of SNP in IL10. Significantly decreased IL-10 production was detected in AA+AG/GG in comparison with the low-producer IL-12p40 (AC/CC+AG/GG) genotype combination after stimulation with C3bgp (2 +/- 4 vs. 29 +/- 14.2 pg/ml; p = 0.0003) and LPS (33.4 +/- 13.5 vs. 93.3 +/- 59.6 pg/ml; p = 0.019). IL-12p40 production was independent of IL10 genotype. The present results demonstrated that the production of IL-10 from PBMC depended on both -1082A*G in IL10 and +16974A*C in IL12B polymorphisms.