In vivo modulation of natural killer cell activity by tamoxifen in patients with bilateral primary breast cancer

Natural killer (NK) cell activity, the autologous mixed lymphocyte reaction (AMLR) and proportions of T cell subpopulations (CD3⁺/CD4⁺ and CD3⁺/CD8⁺) and NK cells (CD16⁺) were studied in 21 patients with bilateral primary breast cancer (BBC), 10 patients with single-breast cancer (SBC) and 20 healthy controls. All patients studied had no evidence of disease and had been off radiotherapy and/or chemotherapy for at least 1 year. Ten patients with BBC were also treated with tamoxifen. Patients with SBC had NK cell activity, AMLR responses and T cell subpopulations that were comparable to those of normal controls. In patients with BBC, a significant (P<0.01) increase in NK activity compared to that in normal controls (42±13% versus 21±10%, effector-to-target cell ratio, 251) and a significant (P<0.05) decrease in CD4⁺ T cell proportions (30±15% versus 49±13%) and absolute numbers (472±82/mm³ versus 953±131/mm³) were found. However, the proliferative response of BBC patients' T lymphocytes in AMLR was in the range of the normal controls. Lymphocytes derived from 10 BBC patients treated with tamoxifen exhibited NK cell activity that was comparable to that of normal controls and patients with SBC, and was significantly (P<0.01) reduced compared to the pretreatment period. BBC patients who received tamoxifen also show a reduction in the proportion of CD4⁺ T cells and in AMLR proliferative responses, which decreased compared to levels in normal controls. Taken together, these results indicate that long-term tamoxifen treatment modulates immune responses in BBC patients.     

In vitro augmentation of rat natural killer (NK) cell activity

In vitro augmentation of rat natural killer (NK) cell activity was produced by 2 types of treatment. Increased activity occurred "spontaneously" when spleen cells were cultured alone at 37 degrees C. This augmentation was dependent on the presence of adherent, phagocytic cells, presumably macrophages, and was independent of LPS of FCS. Normally low levels of NK activity, present in macrophage-depleted cultured cells, could also be boosted in vitro by incubation with Corynebacterium parvum. This augmentation appeared to be independent of both B cells and macrophages and may be due to stimulation of rat NK cells themselves. Both forms of augmentation were associated with the production of interferon, were found in rats of all ages and strains tested, and should provide an excellent in vitro system for detailed studies of activation of rat NK cells.     

In vitro modulation of mouse natural killer (NK) cell activity by the serum thymic factor (FTS)

Previous studies indicated that the serum thymic factor (FTS) could modulate in vivo the level of splenic natural killer (NK) cell activity in mice. The present report shows that such an effect is also observed after a short term in vitro incubation of the effector cells with FTS. The regulatory effects of FTS result in an increase or a decrease of the splenic NK cell cytotoxicity depending upon the age and the mouse strain. Furthermore, FTS is able to enhance the NK cell activity of thymus and bone marrow cells which are known to be weakly reactive in NK cytotoxicity. Depletion experiments demonstrated that the FTS-induced increase of NK cell activity was not mediated by Thy 1+ cells nor macrophages, thus suggesting a direct action of FTS on the effector cells. Comparative studies using other thymic hormones revealed similar patterns of reactivity. These results favor the hypothesis of a close relationship between the thymus and NK cells.     

Chemotherapy-induced modulation of natural killer and lymphokine-activated killer cell activity in euthymic and athymic mice

Combinations of chemotherapy and interleukin-2 (IL-2) aimed at improving therapeutic efficacy in cancer patients have generally proved disappointing. Although chemotherapy blocks tumor growth and sometimes boosts immune functions, most drugs are immunosuppressive, at least transiently. Therefore, it is reasonable to assume that maximal exploitation of the immunostimulatory and antitumor activity of both modalities requires careful coordination of chemotherapy and IL-2 timing. We analyzed the temporal effect of 5-fluorouracil (5-FU, 100–120 mg/kg), cyclophosphamide (CY, 100 mg/kg), Adriamycin (8 mg/kg) and dacarbazine (100 mg/kg) on the activation of natural killer/lymphokine-activated killer (NK/LAK) cells by IL-2 in several strains of euthymic mice and in athymic nude mice. Following in vivo or in vitro exposure to IL-2 1–15 days after chemotherapy, the total lytic activity of the spleen and the number of LAK precursors (LAK-p) were measured. In euthymic mice injected with IL-2 (5×10⁴ Cetus units twice daily for 4–5 days), 5-FU augmented (up to 37-fold, days 1–9) and CY reduced (up to day 6) LAK activity, as compared with that in the IL-2 control. In bulk cultures containing IL-2 (1000 CU/ml, 3–4 days), both 5-FU and CY reduced LAK activity of euthymic mice splenocytes for up to 6 days after chemotherapy, which was followed on day 9 by full recovery. In splenocytes of nude mice, 5-FU increased and CY diminished LAK activation in bulk cultures, starting 3 days after chemotherapy. In athymic mice, 5-FU markedly augmented the total number of LAK-p/spleen (up to 30-fold, days 3–9), as determined by limiting-dilution cultures with IL-2 (for 7–8 days). In euthymic mice, in contrast, LAK-p levels decreased for up to 6–9 days after treatment with 5-FU, Adriamycin or dacarbazine, later recovering to pretreatment levels, whereas CY markedly increased LAK-p (up to 15-fold) when administered 6–12 days before limiting-dilution culture initiation. The effect of chemotherapy on LAK and NK activity was essentially similar. In other experiments, a subset of asialoGM1-LAK-p was found in the spleens of 5-FU-treated mice, but not in untreated mice. Our results suggest that the immunomodulatory effect of chemotherapy on NK/LAK activity in mice is variable and largely depends on the drug itself, the interval between chemotherapy and IL-2 administration, the strain of mice and the assay used.     

Analysis of natural killer activity and natural killer cell subsets in patients with bladder cancer

Summary In order to analyze the state of the natural resistance system of bladder cancer patients in vivo, we measured natural killer (NK) activity and NK cell subsets of peripheral blood lymphocytes (PBL) from 46 patients with bladder cancer and 25 age- and sex-matched healthy volunteers. The mean NK activity in patients with lowstage bladder cancer was similar to that in the controls, while NK activity in patients with high-stage bladder cancer was significantly depressed. The mean proportions of Leu7⁺ cells in patients with both low-stage and highstage bladder cancer were significantly higher than that in the controls. The mean proportion of Leu11a⁺ cells in patients with low-stage bladder cancer was similar to that in the controls, while in patients with high-stage bladder cancer it was significantly higher. This study demonstrates the abnormal immunological state of bladder cancer patients; namely, abnormalities exist not only in NK activity but also in the proportions of circulating NK cell subsets.     

Evaluation of natural killer cell activity

Natural killer (NK) cells are being appreciated not only for their ability to recognize and lyse tumor cells and virus-infected cells but also for their immunoregulatory properties. NK cells provide a first line of defense against invading pathogens with a two pronged attack, lysis of infected cells and secretion of cytokines and chemokines with potent antipathogen effects. This article describes the standard chromium release assay, which measures the ability of NK cells derived from the peripheral blood to lyse appropriate target cells.     

Kupffer cells modulate natural killer cell activity in vitro by producing prostaglandins

The effect of Kupffer cells on natural killer (NK) cell-mediated cytotoxicity was examined. Kupffer cells prepared from rat liver suppressed NK activity against K562 cells and other tumor cell lines through a soluble factor secreted into the culture supernatant. When human peripheral blood mononuclear cells were incubated with the Kupffer cell-culture supernatant, a significant reduction of the cytotoxic activity was observed in the 6-hr chromium-release assay. This activity was dose dependent and was evident at various effector/target cell ratios. Lipopolysaccharide stimulated generation of the suppressive factor released from Kupffer cells in a dose-dependent manner. Suppression of the NK activity was observed when the Kupffer cell-culture supernatant was present in the assay system, whereas pretreatment of effector/target cells with the supernatant had minimal inhibitory effects. Autologous monocytes in human peripheral mononuclear cells were not related to this suppression. The suppressive factor in the fraction had a molecular weight below 10,000. Indomethacin, an inhibitor of prostaglandin synthesis, ameliorated the suppressive effects. These results suggest that Kupffer cells may modulate NK activity by producing PGs (E1, E2, and F2 alpha).     

Renewal of natural killer cells in mice having elevated natural killer cell activity

The present study was designed to examined the dynamics of splenic natural killer (NK) cells under two conditions of enhanced NK cell activity: (1) CBA/J mice given polyinosinic-polycytidylic acid (poly-I:C), an NK-cell-enhancing agent, and 62) untreated athymic nude (nu/nu) mice. The 'total NK cell activity' of the spleen (percentage specific lysis corrected for changes in organ cellularity) increased 5-fold and 2.7-fold after poly-I:C treatment for 1 day and 4 days, respectively. An injection of hydroxyurea (HU), a cell-cycle-toxic drug, given together with either poly-I:C or saline to CBA/J mice resulted in both cases in a 25% reduction in total NK cell activity 1 day later. This suggests that the renewal rate of nondividing NK cells is similar in poly-I:C-treated and saline-injected mice, and that the NK-enhancing effect of poly-I:C is not due to a stimulation of proliferation among NK cell precursors. HU administered simultaneously with poly-I:C or saline for 4 days eliminated NK cell activity in both cases, indicating that spleen NK cell activity is mediated almost entirely by newly formed (less than or equal to 4 days) cells. In nude mice, NK cell activity was assayed at various intervals after an HU depletion period of 2 days. NK depletion was initially more rapid in nu/nu mice than in control (nu/+) mice, although equally profound, and the subsequent recovery of NK cell activity after cessation of HU was also more rapid than in control (nu/+) mice.(ABSTRACT TRUNCATED AT 250 WORDS)     

Physiologic modulation of natural killer cell activity as an index of Alzheimer's disease progression

Patients with Alzheimer's disease (AD) are characterized by an altered sensitivity to cortisol-mediated modulation of circulating lymphocytes. Longitudinal studies are needed to address the clinical applicability of these abnormalities as prognostic factors. Therefore, we designed a longitudinal study to address the clinical applicability of physiologic modulation of Natural Killer (NK) cell activity as a prognostic factor in AD. NK activity was assessed as baseline measurement and in response to modulation by cortisol at 10(-6)M. To verify the immunophysiological integrity of the NK cell population, we tested augmentation of NK cytotoxicity by human recombinant interleukin (IL)-2 (100 IU/ml) as control. The response to modulation by cortisol or by IL-2 was significantly greater in patients with AD. Based on change in the Mini-Mental State score at entry and at 18 months, patients with AD could be assigned to a "fast progression" (Delta > 2 points) or to a "slow progression" group (Delta 相似文献   

Long-term influence of adjuvant therapy on natural killer cell activity in breast cancer

Summary Unstimulated IFN- and IL2-stimulated (NK) cell activities were investigated in patients with breast cancer who had received either local radiotherapy alone or adjuvant chemotherapeutic treatment with CMF combined with radiotherapy 12 to 18 months previously. When tested against the primarily NK-sensitive K562 cell line, patients who had received adjuvant chemotherapeutic treatment with CMF were shown to have a significantly decreased unstimulated and IFN-stimulated NK cell activity, as compared to both patients after radiotherapy only (P<0.002) and P<0.005, respectively) and healthy control persons (P<0.05). The former group of patients also had a significantly decreased IFN-stimulated NK cell activity, when tested against the primarily NK-insensitive Chang hepatoma cell line, as compared to patients after radiotherapy only (P<0.005) and healthy controls (P<0.05). Moreover, patients after radiotherapy only proved to have a significantly increased unstimulated (P<0.01) and IFN-stimulated NK cell activity (K562: P<0.05; Chang hepatoma cell line: P<0.05), as compared to healthy control individuals. In contrast, no difference in IL2-stimulated NK cell activity was detected. The investigation for the expression of CD3 and/or Leu 19 antigens as phenotypic markers of cells with non-MHC restricted cytotoxicity showed a significantly lower percentage of cells with the CD3+ phenotype in patients with breast cancer, irrespective of the chosen post-operative treatment, as compared to healthy controls (P<0.01). Finally, patients with breast cancer who had received radiotherapy only had a significant trend towards an increased percentage of CD³+/Leu 19+ PMNC, as compared to both patients after CMF treatment (P<0.05) and healthy controls (P<0.025). We conclude that patients with breast cancer vary on a long-term basis in their NK activity and in the phenotype of their PMNC depending on their post-operative adjuvant management.Abbreviations NK natural killer cells - IFN interferon - IL 2 interleukin 2 - CMF cyclophosphamide, methotrexate, fluorouracil - ER oestrogen receptor - PMNC peripheral blood mononuclear cells - MHC major histocompatibility complex - CTL cytotoxic T lymphocytes     

The effect of calcitriol on natural killer cell activity in hemodialyzed patients

We report the effect of calcitriol on natural killer (NK) cell activity in patients with chronic renal failure undergoing long-term hemodialysis. Natural killer cytotoxicity was significantly decreased in these patients when compared to healthy control subjects (13.1 +/- 1.3 vs 38.8 +/- 2.4%, P less than 0.001). These patients also have decreased levels of calcitriol (17 +/- 3 vs 36 +/- 3 pg/ml, P less than 0.001). After 14 days of oral treatment with calcitriol at a dose of 0.5 micrograms per day, a significant increase in NK activity was observed (20.2 +/- 1.6%, P less than 0.001). This increase was maintained after 28 days of treatment (21.1 +/- 2%, P less than 0.001). These results suggest that the decreased serum calcitriol might contribute to the diminished NK activity found in hemodialyzed patients, and suggests a new potential therapeutical utility of calcitriol as modulator of the immune function in these patients.     

In vivo modulation of lymphokine-activated killer cell activity by cell wall components of Candida albicans.

We have previously reported that inoculating CD2F1 mice intraperitoneally with five doses of 2 x 10(7) inactivated Candida albicans (CA) cells was associated with the induction of lymphokine-activated killer (LAK)-like effectors. In this study we investigated the ability of some purified cell wall components of CA (CA-CW) to induce LAK-like cells in vivo. Multiple administrations of glucan ghost (GG), a mannoprotein mixture (MP) and a low-protein mannan fraction (M) at variance with whole CA did not induce LAK-like cells in the peritoneal cavity. However, the broad-spectrum antitumor cytotoxicity induced by CA could be recalled to a high level by a booster dose of MP and M, but not GG, given up to 70 days after the multiple CA-treatment. This induced cytotoxicity was maximum when the booster was given on Day +14 after CA-treatment and minimum on Day +70. In CA-treated mice, inoculated on Day +30 with CA or MP, LAK-like cytotoxicity was already significantly increased 4 hr after the booster, but the maximum value was reached at 24 hr. Anti-mannan antibodies did not interfere with LAK-like cells induction by CA because splenectomy before CA-treatment or passive administration of anti-mannan antibodies had no effect on the rapid activation of cytotoxicity by CA or a booster dose of MP. Administration of recombinant human interleukin-2 (rhIL-2) to CA-treated mice induced a higher level of NK activity than that induced by the same dose in untreated control mice, but did not activate LAK-like effectors. The results indicate that LAK-like effectors are easily generated in the peritoneal cavity by a booster with a defined antigenic constituent of CA cell wall for a long period in CA-sensitized mice.     

Neuroimmunomodulation with enkephalins: in vitro enhancement of natural killer cell activity in peripheral blood lymphocytes from cancer patients

To initiate investigations into the effects of enkephalins on immune function in cancer patients, the effect of methionine-enkephalin and leucine-enkephalin on natural killer (NK) cell activity in isolated peripheral blood lymphocytes from cancer patients was investigated. Incubation of lymphocytes with either enkephalin resulted in significant increases in NK cell activity. At effector:target cell ratios of 100:1, 33:1 and 11:1 leucine-enkephalin significantly (p less than 0.05) enhanced NK activity at dilutions of 10(-6), 10(-8), 10(-10), and 10(-14) mg/ml. Similar results were obtained with methionine-enkephalin with the exception that the 10(-6) dilution gave insignificant changes at both the 33:1 and 11:1 cell ratios. The results indicate a difference in dose response to both enkephalins between lymphocytes from cancer patients and normal volunteers.     

Characterization of natural killer cell activity in Macaca nemestrina

Natural killer (NK) cell activity was evaluated in three groups of Macaca nemestrina that varied with respect to SAIDS D retrovirus serotype 2 (SRV-2/W) and viremic status. Target cells used were Raji and K562 cells. No significant differences (ANOVA) in mean NK activity were detected among the three groups of animals studied. Using Raji targets, mean LU₃₀/10⁶ ± SEM was 6.3 ± 1.6 for seronegative (V-Ab−) animals, 7.3 ± 1.5 for seropositive (V-Ab+) animals, and 10.2 ± 3.5 for persistently viremic (V + Ab−) animals. Using K562 targets, mean LU₃₀/10⁶ was 7.6 ± 1.7 for seronegative (V-Ab−) animals, 6.5 ± 2.5 for seropositive (V-Ab+) animals, and 5.1 ± 1.9 for persistently viremic (V+Ab−) animals. Percentage blood CD16⁺ and CD8⁺cells also were not different in the three groups of animals. NK activity did not always correlate with percentage of CD16⁺ or CD8⁺ cells in peripheral blood at the time the assays were done. In persistently viremic animals, there was a strong positive correlation between percent CD16⁺ and CD8⁺ cells and NK activity using K562 cells but not Raji cells. Depletion experiments indicated that lysis was mediated by both CD8⁺ and CD16⁺ cells with both Raji and K562 cells. However, Raji targets were a better indicator of killing mediated by CD16⁺ cells. Our studies indicate that M. nemestrina may be classified as high or low responders with regard to NK activity, and there was no correlation with SRV-2/W viral or antibody status. Additionally, our results suggested that group housing of M. nemestrina was usually associated with increased NK activity. In conclusion, studies of NK activity in M. nemestrina should consider target cells used, phenotype of effectors, endogenous (high or low) levels of NK activity in individual animals, and housing conditions. © 1996 Wiley-Liss, Inc.     

Stage-related decrease in natural killer cell activity in untreated patients with mycosis fungoides

Summary Natural killer activity of peripheral blood mononuclear cells against the human cell line K 562 was evaluated in 11 patients with mycosis fungoides and simultaneously in 10 age-and sex-matched controls. In the patient group, nine had no previous treatment and in two topical therapy had been discontinued more than 3 months before. None had any associated disease or concurrent therapy that could interfere with the immune system. Patients with early disease showed a mean specific lysis and a range of individual data similar to the controls whereas patients with advanced disease had a significant defect of natural killer activity at effector: target ratios of 100:1, 50:1, and 25:1, as shown by the Mann-Whitney test. Preincubation of effector cells with -interferon for 1 h in a single patient with low natural killing capacity led to a clear increase of the specific lysis, suggesting reduced functional activity rather than depletion of effector cells.