Dynamic changes in the numbers of different subsets of peripheral blood NK cells in patients with systemic lupus erythematosus following classic therapy

Imbalance of natural killer (NK) cells is associated with the development of systemic lupus erythematosus (SLE). However, little is known about the dynamic changes on NK cells following therapy. This study aimed at examining the impact of classic therapies on the numbers of different subsets of NK cells in new-onset SLE patients. The numbers of different subsets of peripheral blood NK cells in 24 new-onset SLE patients before, 4 and 12 weeks post the classic therapies, and 7 healthy controls were determined by flow cytometry. The potential correlation between the numbers of NK cells and the values of clinical measures was analyzed. In comparison with that before treatment, the numbers of NK, NKG2C+, and KIR2DL3+ NK cells were significantly increased while the numbers of NKp46+ and NKG2A?+?NK cells significantly decreased at 4 and/or 12 weeks post the treatment only in the drug well-responding patients, but not in those poor responders (P?相似文献   

Phenotype and function of natural killer cells in systemic lupus erythematosus: Excess interferon‐γ production in patients with active disease

Objective

To determine the phenotype and the functionality of natural killer (NK) cells in patients with systemic lupus erythematosus (SLE).

Methods

A total of 94 patients with SLE (91 women and 3 men) were compared with 26 healthy controls. Active SLE was defined by an SLE Disease Activity Index score ≥4. Immunologic tests were performed using nonactivated and/or interleukin‐2 (IL‐2)–activated peripheral blood mononuclear cells. NK cell phenotype was determined by flow cytometry. NK cell natural cytotoxicity and antibody‐dependent cellular cytotoxicity (ADCC) were determined by ⁵¹Cr release and CD107a degranulation experiments. Intracellular interferon‐γ (IFNγ) production by NK cells was evaluated after overnight stimulation with IL‐12 and IL‐18. IFNα levels were assessed using an antiviral cytopathic bioassay.

Results

The absolute NK cell count was decreased in patients with active SLE, but the relative frequencies of total CD3−CD56^bright NK cells and CD3−CD56^dim NK cells were unaffected. The CD3−CD56^dim NK cells in patients with active SLE displayed unique phenotypic characteristics, including significant increases in CD69 and NKG2A and decreased expression of Fcγ receptor type IIIa/CD16, CD8α, and the killer cell immunoglobulin‐like receptor (KIR) KIR2DL1/KIR2DS1. Concomitant with these findings, NK cells from SLE patients had lower cytotoxicity but a normal level of ADCC compared with NK cells from healthy controls. There was a significant positive correlation between the increased level of IFNα in the serum and the enhanced frequency of IFNγ+ cells in patients with active SLE (r = 0.370, P = 0.04).

Conclusion

NK cells in patients with active SLE display phenotypic and functional features associated with activation. Furthermore, NK cells from patients with active SLE have the capacity to produce large amounts of IFNγ. This could contribute to the dysregulation of the link between innate and adaptive immunity seen in SLE.

     

Inhibition of natural killer cell activity by serum from patients with systemic lupus erythematosus: roles of disease activity and serum interferon.

Among their immunological alterations patients with systemic lupus erythematosus (SLE) have been shown to have diminished natural killer (NK) cell activity. This abnormality is at least in part related to humoral factors, as sera from patients with SLE can inhibit the NK activity of peripheral blood mononuclear cells from normal individuals. The present study extends these findings to demonstrate that the inhibitory ability of sera from patients with SLE varies with disease activity. Furthermore, sera from patients with active SLE containing interferon (IFN), a potent stimulator of NK activity, were equally or more inhibitory than sera which did not contain IFN. Thus the factors in SLE sera which can inhibit NK function vary with disease activity and cannot be overcome by IFN present in these sera.     

Impaired release of a soluble natural killer cytotoxic factor in systemic lupus erythematosus

Disease states characterized by abnormalities in immune regulation often demonstrate concomitant abnormalities in cytotoxicity mediated by natural killer (NK) cells. For example, some patients with systemic lupus erythematosus (SLE) have depressed NK activity despite the presence of normal numbers of effector cell:target cell conjugates. This study was designed to determine if defects in NK cell function were directly related to impaired release of a soluble cytotoxic factor. NK activity of peripheral blood mononuclear cells and large granular lymphocytes was measured using 51Cr-labeled K562 target cells in 4-hour release assays. The SLE patients had significantly decreased NK activity relative to normal controls. However, the number of effector cell:target cell conjugates was not different in SLE patients versus control subjects. The release of a soluble natural killer cytotoxic factor (NKCF) by peripheral blood mononuclear cells was measured by cytotoxicity induced in K562 cells. NKCF was released preferentially by suspensions enriched in NK cells (large granular lymphocytes). At a 1:1 dilution, NKCF release was significantly lower in SLE patients than in controls. The release of NKCF correlated well with NK activity. Thus, this study shows that the defect in NK cell activity in SLE patients may be related to an impairment in release of a soluble cytotoxic factor with specificity for NK cell-sensitive targets.     

NK cells dysfunction in systemic lupus erythematosus: relation to disease activity

Through their cytotoxic capacities and cytokine production, natural killer (NK) cells modulate autoimmune diseases. However, their role in the pathogenesis of systemic lupus erythematosus (SLE) has not been extensively studied. The aim of this study was to analyse the immunophenotypic and functional characteristics of the two major NK cell subsets in SLE and relate them with disease activity. Peripheral blood samples from 44 patients with active (n?=?18) and inactive SLE (n?=?26) and 30 controls were analysed by flow cytometry to evaluate NK cell subsets, according to: the differential expression of CXCR3 and CD57; expression of granzyme B and perforin; and production of interferon gamma (IFN-γ) and tumor necrosis alpha (TNF-α), after PMA/ionomycin activation. A clear decrease in absolute and relative numbers of circulating NK cells was found in SLE, particularly in active disease, while the proportions of the major NK cell subsets were unaffected. Active SLE was associated with a reduced CXCR3 expression on both NK cell subsets and a lower frequency of CD56^dim NK cells expressing CXCR3. Furthermore, granzyme B expression was decreased in both SLE groups, but the percentage of NK cells expressing granzyme B and perforin was higher, particularly in active disease. We found a significant decrease in the percentage of CD56^bright and CD56^dim NK cells producing TNF-α and of its expression on CD56^dim NK cells in active disease, while IFN-γ expression on CD56^bright NK cells was increased in both SLE groups. Our findings suggest that NK cell subsets exhibit unique phenotypic and functional changes that are particularly evident in active SLE, and they may have the potential to affect the disease outcome.     

Abnormal interferon modulation of natural cytotoxicity in systemic lupus erythematosus. Relation to suppressive serum factors

In the present study we examined one aspect of the derangement in natural cytotoxicity (natural killer, NK) activity observed in some patients with systemic lupus erythematosus (SLE), i.e., the lack of enhancement of NK activity usually seen with interferon (IFN). NK activity of SLE patients as a group was 23.0 +/- 3.9 lytic units (LU)/10(7) cells (mean +/- SE). This contrasted with the NK activity found in normal controls (45.0 +/- 3.8 LU/10(7) cells) (P less than 0.05). The enhancement seen with IFN was an increase of 15.4 +/- 4.0 LU/10(7) cells in SLE patients compared with 104.6 +/- 192 LU/10(7) cells in control subjects (P less than 0.05). SLE sera and aggregated IgG (Agg-IgG) also inhibited the increase in NK activity of normal peripheral blood mononuclear cells after IFN priming. The results reported here support the hypothesis that the impaired baseline NK activity and poor response to IFN noted in SLE are secondary, in part, to the presence of inhibitory serum factors and preactivation by IFN.     

Impaired natural killer cell function in systemic lupus erythematosus. Relationship to interleukin-2 production

Immune regulation requires clonal expansion of regulatory T cells which is dependent on the presence of interleukin-2 (IL-2). Previously, both natural killer (NK) cell function and IL-2 production were found to be depressed in systemic lupus erythematosus (SLE). This study was designed to determine the relationship between IL-2 production and NK cell activity in SLE. NK activity as determined by a standard 4-hour 51Cr-release assay was impaired in SLE (11.0 +/- 5.1 lytic units/10(7) cells) compared with controls (25.1 +/- 7.1 lytic units/10(7) cells) (P less than 0.05). IL-2 production was induced with concanavalin A and phorbol ester and quantitated using the IL-2 dependent cell line HT-2. IL-2 production was impaired in only 1 SLE patient, despite concomitant abnormalities in NK function in the SLE group as a whole. Moreover, in patients with impaired NK activity, incubation of lymphocytes with exogenous IL-2 did not restore NK activity to normal levels. These findings demonstrate that impaired NK activity in SLE is independent of IL-2 production and that defects in IL-2 production in SLE may not be as common as previously reported.     

Natural killer cell activity in Sj?gren's syndrome and systemic lupus erythematosus: stimulation with interferons and interleukin-2 and correlation with immune complexes.

Natural killer (NK) cell activity and its stimulation by interferons (IFNs) and interleukin-2 (IL-2) are diminished in Sjögren''s syndrome and systemic lupus erythematosus (SLE). Serum samples of these patients often contain circulating immune complexes, which may influence NK cell activity. Sixteen patients with Sjögren''s syndrome (14/16 immune complex positive), 14 with SLE (9/14 immune complex positive), and 11 controls (immune complex negative) were studied. Mononuclear cells collected from a Percoll gradient were preincubated with recombinant IFN-alpha (rIFN-alpha) (100 U/ml), rIFN-gamma (1000 U/ml), rIL-2 (100 U/ml), or without cytokine. Natural killer cell activity was determined by incubating the mononuclear cells with carboxyfluorescein labelled K562 cells, and the percentage decrease of fluorescence was measured on an FACS Analyzer. In patients with Sjögren''s syndrome and SLE NK cell activity and the numbers of cells expressing the NK cell associated antigens CD16 and Leu7 were diminished compared with the controls. Interleukin-2 stimulated NK cell activity significantly in comparison with the non-stimulated value in all studied groups, whereas IFN-gamma only stimulated NK cell activity in both patient groups and IFN-alpha only in patients with Sjögren''s syndrome. There was no correlation between NK cell activity, with or without stimulation, and the immune complex concentrations. It is concluded that NK cell activity is decreased in Sjögren''s syndrome and SLE and that it may be partially restored by IL-2 and IFN-gamma in both diseases, and by IFN-alpha in Sjögren''s syndrome. The decrease of NK cell activity did not correlate with immune complex concentrations; on the other hand, decreased numbers of NK cells (CD16+ or Leu7+) and of cytokine concentrations might be important in the impaired NK cell activity in both diseases.     

Effects of serum from patients with system lupus erythematosus on leukocyte cytotoxicity: modulation of NK activity and ADCC

The ability of sera from patients with systemic lupus erythematosus (SLE) to alter the natural killer (NK) cell activity and antibody dependent cell mediated cytotoxicity (ADCC) of peripheral blood mononuclear cell populations from normal donors was determined employing 4-h 51Cr release assays. SLE sera significantly lowered the NK activity of both whole mononuclear cell populations (MN) (26 +/- 3% decrease) (mean +/- SEM) and lymphocyte enriched populations (24 +/- 5%) toward K562 targets when compared to results with sera from normal donors. The continuous presence of serum was not required for this effect since MN effector cells preincubated with sera and then washed also exhibited diminished NK activity. SLE sera decreased only slightly lymphocyte-mediated ADCC to either erythrocyte (human 0 + RBC) or tumor cell (human CEM T lymphoblast) targets. ADCC by isolated monocytes, however, was significantly diminished by SLE sera (54 +/- 5%). These data suggest that in patients with SLE, serum factors may be responsible for alteration of both NK activity and ADCC.     

Impaired natural killer cell function in systemic lupus erythematosus

Immune regulation requires clonal expansion of regulatory T cells which is dependent on the presence of interleukin-2 (IL-2). Previously, both natural killer (NK) cell function and IL-2 production were found to be depressed in systemic lupus erythematosus (SLE). This study was designed to determine the relationship between IL-2 production and NK cell activity in SLE. NK activity as determined by a standard 4-hour ⁵¹Cr-release assay was impaired in SLE (11.0 ± 5.1 lytic units/10⁷ cells) compared with controls (25.1 ± 7.1 lytic units/10⁷ cells) (P < 0.05). IL-2 production was induced with concanavalin A and phorbol ester and quantitated using the IL-2 dependent cell line HT-2. IL-2 production was impaired in only 1 SLE patient, despite concomitant abnormalities in NK function in the SLE group as a whole. Moreover, in patients with impaired NK activity, incubation of lymphocytes with exogenous IL-2 did not restore NK activity to normal levels. These findings demonstrate that impaired NK activity in SLE is independent of IL-2 production and that defects in IL-2 production in SLE may not be as common as previously reported.     

Abnormal interferon modulation of natural cytotoxicity in systemic lupus erythematosus relation to suppressive serum factors

In the present study we examined one aspect of the derangement in natural cytotoxicity (natural killer, NK) activity observed in some patients with systemic lupus erythematosus (SLE), i.e., the lack of enhancement of NK activity usually seen with interferon (IFN). NK activity of SLE patients as a group was 23.0 ± 3.9 lytic units (LU)/10⁷ cells (mean ± SE). This contrasted with the NK activity found in normal controls (45.0 ± 3.8 LU/10⁷ cells) (P < 0.05). The enhancement seen with IFN was an increase of 15.4 ± 4.0 LU/10⁷ cells in SLE patients compared with 104.6 ± 192 LU/10⁷ cells in control subjects (P < 0.05). SLE sera and aggregated IgG (Agg-IgG) also inhibited the increase in NK activity of normal peripheral blood mononuclear cells after IFN priming. The results reported here support the hypothesis that the impaired baseline NK activity and poor response to IFN noted in SLE are secondary, in part, to the presence of inhibitory serum factors and preactivation by IFN.     

Response of peripheral blood mononuclear cells from lupus patients to stimulation by CpG oligodeoxynucleotides

OBJECTIVES: Increased levels of hypomethylated CpG-containing DNA in sera from patients with systemic lupus erythematosus (SLE) may contribute to the initiation and/or perpetuation of the disease. This study characterizes the in vitro response of peripheral blood mononuclear cells (PBMC) from SLE patients to CpG DNA. METHODS: Secretion of cytokines and IgM, cell proliferation and up-regulation of co-stimulatory molecules were evaluated in PBMC from SLE patients (n=24) and normal controls (n=24) after stimulation with synthetic oligodeoxynucleotides (ODN) containing CpG motifs. RESULTS: Up-regulation of co-stimulatory molecules and the secretion of interferon-alpha and interleukin-6 (IL-6) in response to CpG ODN was significantly reduced in monocytes and dendritic cells from SLE patients. Secretion of interferon-gamma by natural killer (NK) cells was also reduced. In contrast, the IgM and IL-10 response of B cells to CpG ODN was normal. CONCLUSION: Monocytes, dendritic cells and NK cells from SLE patients respond abnormally to CpG ODN stimulation, which may contribute to the cytokine imbalance observed in SLE.     

Relationship between circulating interferon and anti-interferon antibodies and impaired natural killer cell activity in systemic lupus erythematosus

Interferon (IFN) production and response are impaired in a high percentage of systemic lupus erythematosus (SLE) patients. In addition, elevated serum levels of alpha-IFN or anti-alpha-IFN antibodies are present in some SLE patients. This study examined the relationship of circulating IFN and anti-IFN antibodies to the impairment of natural killer (NK) cell function in SLE. All 15 SLE patients studied had measurable circulating alpha-IFN, while the normal controls had minimal serum IFN. Neither patient nor control sera contained any detectable anti-alpha-IFN activity. However, most of the SLE patients demonstrated defects in NK cell function. Because these defects in NK cell function appeared to be associated with circulating IFN, but not anti-IFN, antibodies, the effect of prolonged in vitro IFN exposure on NK cell function of peripheral blood mononuclear cells was determined. It was found that prolonged exposure to IFN induced both an apparent defect in IFN response and a definite impairment of baseline NK cell function. These results suggest that prolonged elevation of circulating alpha-IFN levels could be responsible, in part, for the defects in natural cytotoxicity present in SLE.     

Changes in immune cell frequencies after cyclophosphamide or mycophenolate mofetil treatments in patients with systemic lupus erythematosus

This study was designed to explore the profile of immune cell subsets, including T, B, natural killer (NK), and NKT cells, in systemic lupus erythematosus (SLE) patients, and to determine their relationships with the clinical index and the effects of cyclophosphamide (CYC) and mycophenolate mofetil (MMF) treatment. SLE patients (n?=?28) and age/sex-matched healthy controls (n?=?28) were evaluated. The patients were equally divided into two treatment groups: intravenous drip (IVD) with CYC and prednisolone, and oral MMF and IVD with prednisolone. SLE peripheral blood samples were taken immediately prior to treatment and after 4?weeks of drug treatment. T, B, NK, and NKT cell subsets were measured by flow cytometry. Double-stranded DNA antibody and Sm antibody were detected by indirect immunofluorescence. Serum C3, C4, and C-reactive protein were determined by scatter turbidimetry. The percentages of CD3+CD4+ T, CD3-CD16CD56+ NK, and CD3+CD16CD56+ NKT cells and the CD4+/CD8+ ratio were significantly lower in SLE patients, while CD3+CD8+ T and CD3-CD19+ B cells were higher than the controls. The lymphocyte subsets were significantly correlated with the SLE disease activity index (SLEDAI) and complement factors (C3, C4). Four weeks of CYC or MMF treatment led to a significant increase in CD3+CD4+ T cells (P?相似文献   

Natural cell mediated cytotoxicity in systemic lupus erythematosus

The significantly reduced natural killer (NK) cell activity was demonstrated in the peripheral blood lymphocytes (PBL) from 20 female patients with systemic lupus erythematosus (SLE) when compared with NK activity in the age and sex-matched controls. The reduced NK activity did not correlate with clinical parameters including daily prednisolone doses, serum CH50, antinuclear antibody titers, antiDNA activities, circulating immune complex levels, and cytotoxic activities of antilymphocyte antibodies (ALA). The effects of prednisolone and aggregated human IgG on NK activity were only slightly suppressive in the in vitro studies. When normal PBL were pretreated with rabbit complement and SLE sera containing ALA, the NK activity of the surviving cells was markedly decreased. The decrease was specific and did not seem to be due to the physical hindrance of the dead cells. Other heterologous ALA of rabbit origin did not exert a suppressive effect on NK activity. These results suggest that the suppressed NK activity in SLE can be ascribed to an antiNK cell specific antibody in lupus sera, although the participation of circulating immune complexes was not completely excluded.     

Down-regulation of natural killer cells and of gamma/delta T cells in systemic lupus erythematosus. Does it correlate to autoimmunity and to laboratory indices of disease activity?

A depletion of natural killer (NK) cells seems to play a role in the course of systemic lupus erythematosus (SLE) whereas the possible involvement in this disease of T cell receptor (TCR) gamma/delta positive T cells is still debated. The aim of this study was to evaluate the peripheral blood mononuclear cells (PBMCs) that express NK surface markers CD16 and CD56 or gamma/delta TCR antigen in 58 SLE patients, investigating the possible role of these cell subsets involved in non-MHC-restricted cytotoxicity and their relationship with the main clinical and laboratory parameters. SLE patients had, with respect to controls, considerably decreased values of NK cells (P<0.0004 in percentage and P<0.00004 as absolute number), of non-MHC-restricted T cytotoxic lymphocytes (P<0.007 and P<0.0015, respectively) and of T cells expressing gamma/delta TCR (P<0.02 and P<0.004, respectively). The absolute numbers of these cell subsets positively correlated to each other (P<0.009). gamma/delta T cells inversely correlated with higher ESR values, both percentually (P<0. 006; r=-0.367) and in absolute number (P<0.009; r=-0.350). Moreover, the percentage values of this cell subset inversely correlated with higher levels of CRP (P<0.05; r=-0.256) while SLE patients with anti-SSB/La antibodies had lower values of T lymphocytes bearing gamma/delta TCR, both as percentage (P<0.008) and as absolute number (P<0.02). Our study indicates that non-MHC-restricted cytotoxicity, shared by NK, NK-like and gamma/delta T cells, may be down-regulated in SLE patients, owing to a significant reduction of these PBMC subsets. These specific cell subset impairments seem to affect only some aspects of the disease, suggesting a weakening of the regulatory properties of these cells in the control of different immunological and inflammatory features of SLE, that could be of importance in its clinical expression.     

Natural killer T cells in families of patients with systemic lupus erythematosus: their possible role in regulation of IGG production

OBJECTIVE: To determine whether there is a link between the frequency of natural killer T (NKT) cells and high levels of IgG in patients with systemic lupus erythematosus (SLE) and their relatives. METHODS: Blood samples were obtained from patients with SLE, their first-degree relatives, patients with rheumatoid arthritis (RA), and healthy control subjects. The frequency of NKT cells (defined as CD56+ T cells) was expressed as a percentage of total blood lymphocytes. Plasma levels of total IgG and IgM, and IgG antibodies to double-stranded DNA (dsDNA) were determined. RESULTS: The frequency of NKT cells was lower in patients with SLE than in control subjects. No such decrease was observed in the relatives of patients with SLE or in patients with RA. High levels of IgG were observed in both patients with SLE and their relatives, while low levels of IgM were observed in these same groups. In relatives of patients with SLE, an inverse correlation between the frequency of NKT cells and IgG levels was observed. Moreover, raised levels of IgG in patients with SLE and their relatives and high levels of IgG anti-dsDNA in patients were associated with low frequencies of NKT cells. CONCLUSION: These results suggest that NKT cells have an important role in the regulation of IgG production, although NKT cells with invariant T cell receptors may not necessarily be involved. NKT cells in the setting of SLE could lack the cytokine stimulus from NK or other cells that is needed to exert control on IgG production. Enhancement of NKT cell activity may provide a novel basis for therapy in SLE.     

Natural and antibody-dependent cellular cytotoxicity in children with systemic lupus erythematosus and juvenile dermatomyositis

Thirteen children with systemic lupus erythematosus (SLE) and 5 with juvenile dermatomyositis (JDM) were studied for natural cytotoxicity (NK) and antibody-dependent cellular cytotoxicity (ADCC). In vitro prednisolone at pharmacological levels failed to alter NK or ADCC in adult controls, nor did it alter ADCC in any children studied. ADCC was normal, but NK was decreased in SLE (p less than .005) and JDM (p less than .05) compared to controls. Since NK but not ADCC is decreased in these patients, different lymphocyte populations may mediate these 2 cytotoxic functions.     

神经颗粒素在系统性红斑狼疮患者外周血单个核细胞中的表达

目的 探讨神经颗粒素在系统性红斑狼疮(SLE)患者和正常人外周血单个核细胞(PBMCs)的表达状态.方法 对比分析SLE PBMCs基因表达系列分析(SAGE)文库的高表达标签,并采用反转录聚合酶链反应(RT-PCR)法检测与正常人群有明显差异表达的神经颗粒素在SLE患者PBMCs的mRNA表达水平.结果 对比分析SLE PBMCs和正常人各类淋巴细胞SAGE文库显示:神经颗粒素标签仅异位高表达于SLE患者,而几乎不表达于正常人各类淋巴细胞.RT-PCR检测证实:活动组SLE患者神经颗粒素mRNA表达水平较正常对照明显增加(P＜O.001),而缓解组SLE患者其表达水平仅稍有增加(P＞O.05).结论 神经颗粒素作为一种前凋亡因子,高表达于SLE PBMCs,可能介导或参与SLE异常的免疫调节反应.