Blood NK Cells (blood + nk_cell)

Distribution by Scientific Domains
Medical Sciences100%

Kinds of Blood NK Cells

  • peripheral blood nk cell
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    Selected Abstracts

    ORIGINAL ARTICLE: Peripheral Blood NK Cells Reflect Changes in Decidual NK Cells in Women With Recurrent Miscarriages

    AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 2 2010
    Dong Wook Park
    Citation Park DW, Lee HJ, Park CW, Hong SR, Kwak-Kim J, Yang KM. Peripheral blood NK cells reflect changes in decidual NK cells in women with recurrent miscarriages. Am J Reprod Immunol 2010; 63: 173,180 Problem, We aimed to investigate if peripheral blood natural killer (pNK) cell levels are correlated with decidual NK (dNK) cell levels, and if chemokine expression has any role in dNK cell regulation. Method of study, Decidual tissues of women having two or more miscarriages with normal karyotype were collected after miscarriage and an immuno-histochemisty study was made. pNK cells were evaluated using flow cytometric analysis. Results, The %CD3,/56+ and %CD3,/56+/16+ pNK cells showed a significant correlation with mean number of CD56+ dNK cells. The number of decidual CD16+ cells was significantly higher in women with elevated pNK (,15%) than that of normal pNK (<15%). The %CD3,/56+ and %CD3,/56+/16+ pNK cells showed an inverse correlation with duration of gestation. The CCL3+ and CXCL12+ cells were present in the decidua; however, staining intensity was not correlated with number of dNK cells. Conclusion, The pNK cell levels reflect changes in dNK cell levels. This implicates that pNK cell level is a clinically useful marker to predict pregnancy outcome. Further study is needed to examine if elevated pNK cells enhance recruitment of dNK cells in the decidua. [source]

    ORIGINAL ARTICLE: Correlation Between Natural Cytotoxicity Receptors and Intracellular Cytokine Expression of Peripheral Blood NK Cells in Women with Recurrent Pregnancy Losses and Implantation Failures

    AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 6 2009
    Atsushi Fukui
    Problem, Natural cytotoxicity receptors (NCRs) are unique markers, which regulate NK cell cytotoxicity and cytokine production. We investigated whether women with recurrent pregnancy losses (RPLs) and implantation failures have aberrant correlation between NCRs and intracellular cytokine expression of NK cells. Method of study, Peripheral blood NK cells (CD56dim and CD56bright) were analyzed for NCRs (NKp46, NKp44 and NKp30) and cytokine expression (TNF-,, IFN-,, IL-4, IL-10) using flow cytometry in RPL (n = 22), implantation failures (n = 23) or controls (n = 15). Results, In type 1 cytokine studies, CD56bright/NKp30+ cells in controls (r = 0.696, P < 0.05) were positively correlated with CD56bright/IFN-,+/TNF-,+ cells. CD56bright/NKp46+ cells in implantation failures (r = ,0.76, P < 0.01) were negatively correlated with CD56bright/IFN-,+/TNF-,, cells. RPL did not have any correlation. In type 2 cytokine studies, CD56+/NKp46+ cells (r = 0.758, P < 0.01) and CD56+/NKp30+ cells (r = 0.637, P < 0.05) were positively correlated with CD56bright/IL-4+/IL-10+ cells in controls. CD56+/NKp30+ cells in implantation failures (r = ,0.778, P < 0.05) were negatively correlated with CD56bright/IL-10+/IL-4+ cells. There were no correlations in RPL. Conclusion, Recurrent pregnancy losses and implantation failures have lack of, or negative correlation between NCRs and intracellular cytokines expression. This observation suggests that excessive pro-inflammatory cytokine expression in NK cells in RPL and implantation failures may be exerted through the NCRs or interruption of signal transduction processes. [source]

    Study of cord blood natural killer cell suppressor activity

    EUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2001
    S. El Marsafy
    Abstract: We tested the immunosuppressive effect of cord blood (CB) natural killer (NK) cells using highly purified CB NK cells in mixed lymphocyte cultures (MLC) containing autologous CB T cells as responders. Control cultures were done without NK cells. Our findings revealed that CB NK cells induced a dose-dependent inhibition of T lymphocyte proliferation as evidenced by decreased 3H-thymidine incorporation in MLC. The T cell alloproliferation was significantly decreased in the presence of an NK cell to responder cell ratio of 0.1, 0.2 or 0.4 compared with control cultures done without NK cells (p=0.02, 0.003 and 0.0002, respectively). T lymphocyte inhibition was also achieved using irradiated CB NK cells and still demonstrable on addition of disparate CB NK and T cells to the MLC. In agreement with previous reports, adult blood NK cells inhibited the alloreactive T cells in the MLC using adult T lymphocytes as responders. Compared to control cultures done without NK cells, statistically significant inhibition of 3H-thymidine incorporation in MLC was observed at a ratio of NK cells to responder cells ratio of 0.2 or 0.4 (p=0.02). To investigate the mechanism whereby CB NK cells can interfere with the development of alloreactive T cells in MLC, we measured the tumour necrosis factor-, (TNF-,) concentrations in MLC supernatants using NK cell-depleted or unseparated CB mononuclear cells (MNC) as responders. The results revealed significantly high levels of TNF-, in the absence of NK cells (p=0.007). We conclude that CB NK cells suppress alloreactive T lymphocytes as do their counterparts in adult blood. However, the high NK to T cell ratio in CB could contribute to a more marked suppressive potential compared to that in adult blood. The mechanism of NK-mediated inhibition is likely related to disruption of the TNF-, pathway of T-lymphocyte activation. [source]

    NK cells of human secondary lymphoid tissues enhance T cell polarization via IFN-, secretion

    EUROPEAN JOURNAL OF IMMUNOLOGY, Issue 9 2006
    Barbara Morandi
    Abstract Human secondary lymphoid tissues harbor NK cells that predominantly secrete cytokines in response to activation. Here, we demonstrate that these immunoregulatory NK cells assist in the Th1 polarization of primary immune responses, induced by dendritic cells. Tonsilar, but not peripheral blood NK cells enhanced the expansion of IFN-,-producing CD4+ T cells via their superior ability to produce IFN-,. Addition of IFN-, increased Th1 polarization while antibody blocking of this cytokine abolished NK cell-dependent Th1 polarization. Our data suggest that NK cells in secondary lymphoid organs assist priming of Th1 cells via cytokine secretion and this effect should be harnessed during vaccination against viruses and tumors. [source]

    REVIEW ARTICLE: Tolerance Mechanisms in Pregnancy: A Reappraisal of the Role of Class I Paternal MHC Antigens,

    AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 2 2010
    David A. Clark
    Citation Clark DA, Chaouat G, Wong K, Gorczynski RM, Kinsky R. Tolerance mechanisms in pregnancy: a reappraisal of the role of class I paternal MHC antigens. Am J Reprod Immunol 2010; 63: 93,103 Problem, Allogeneic pregnancies have a survival advantage over syngeneic pregnancies, and paternal Class I MHC antigens have been implicated. In humans, HLA-C and HLA-G and E are expressed by subpopulations of fetal trophoblast. In mice, Qa-2, a Class Ib antigen, and classical H-2K antigens have been described. However, the mechanism of prevention of embryo demise in utero has not been critically assessed, and a number of conflicting ideas have not been addressed. The ,, T-cell receptor recognizes peptide bound to the groove in Class I MHC, and peptides have profound effects on the interaction of KIR receptors on T and NK cells with Class I MHC. Methods, Data on prevention of pregnancy loss (abortion) in poly IC-treated mice were reviewed along with information about prevention of losses in the abortion-prone CBA × DBA/2 model. This information was combined with data on paternal antigen expression at different times in pregnancy when key events determining outcome are thought to transpire, and role of tolerance signaling molecules such as CD200. Current data on models supporting a role for ,true' uterine NK cells (TuNKs) versus blood NK cells in the uterus (BuNKs) and role of MHC,KIR interaction were reviewed along with incompatible data in the literature. Results, Whilst paternal Class I MHC appears important, there is an important role for paternal non-MHC minor antigens (small peptides) that bind to the antigen-presenting groove of Class I MHC. BuNKs along with CD8+ T cells and Treg cells appear more important than TuNKs where the role of the latter appears primarily to promote angiogenesis. When during pregnancy the maternal immune system cells are first exposed to paternal Class I + peptide is uncertain, but at the time of implantation, if not earlier, seems likely. Conclusion, Suppression of pregnancy loss by paternal/embryo Class I MHC depends on the presence of paternal peptides. This greatly complicates existing models of Class I,KIR interactions in feto-maternal tolerance or rejection. It is important to consider all the data when devising explanatory models. [source]

    ORIGINAL ARTICLE: Peripheral Blood NK Cells Reflect Changes in Decidual NK Cells in Women With Recurrent Miscarriages

    AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 2 2010
    Dong Wook Park
    Citation Park DW, Lee HJ, Park CW, Hong SR, Kwak-Kim J, Yang KM. Peripheral blood NK cells reflect changes in decidual NK cells in women with recurrent miscarriages. Am J Reprod Immunol 2010; 63: 173,180 Problem, We aimed to investigate if peripheral blood natural killer (pNK) cell levels are correlated with decidual NK (dNK) cell levels, and if chemokine expression has any role in dNK cell regulation. Method of study, Decidual tissues of women having two or more miscarriages with normal karyotype were collected after miscarriage and an immuno-histochemisty study was made. pNK cells were evaluated using flow cytometric analysis. Results, The %CD3,/56+ and %CD3,/56+/16+ pNK cells showed a significant correlation with mean number of CD56+ dNK cells. The number of decidual CD16+ cells was significantly higher in women with elevated pNK (,15%) than that of normal pNK (<15%). The %CD3,/56+ and %CD3,/56+/16+ pNK cells showed an inverse correlation with duration of gestation. The CCL3+ and CXCL12+ cells were present in the decidua; however, staining intensity was not correlated with number of dNK cells. Conclusion, The pNK cell levels reflect changes in dNK cell levels. This implicates that pNK cell level is a clinically useful marker to predict pregnancy outcome. Further study is needed to examine if elevated pNK cells enhance recruitment of dNK cells in the decidua. [source]

    ORIGINAL ARTICLE: Correlation Between Natural Cytotoxicity Receptors and Intracellular Cytokine Expression of Peripheral Blood NK Cells in Women with Recurrent Pregnancy Losses and Implantation Failures

    AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 6 2009
    Atsushi Fukui
    Problem, Natural cytotoxicity receptors (NCRs) are unique markers, which regulate NK cell cytotoxicity and cytokine production. We investigated whether women with recurrent pregnancy losses (RPLs) and implantation failures have aberrant correlation between NCRs and intracellular cytokine expression of NK cells. Method of study, Peripheral blood NK cells (CD56dim and CD56bright) were analyzed for NCRs (NKp46, NKp44 and NKp30) and cytokine expression (TNF-,, IFN-,, IL-4, IL-10) using flow cytometry in RPL (n = 22), implantation failures (n = 23) or controls (n = 15). Results, In type 1 cytokine studies, CD56bright/NKp30+ cells in controls (r = 0.696, P < 0.05) were positively correlated with CD56bright/IFN-,+/TNF-,+ cells. CD56bright/NKp46+ cells in implantation failures (r = ,0.76, P < 0.01) were negatively correlated with CD56bright/IFN-,+/TNF-,, cells. RPL did not have any correlation. In type 2 cytokine studies, CD56+/NKp46+ cells (r = 0.758, P < 0.01) and CD56+/NKp30+ cells (r = 0.637, P < 0.05) were positively correlated with CD56bright/IL-4+/IL-10+ cells in controls. CD56+/NKp30+ cells in implantation failures (r = ,0.778, P < 0.05) were negatively correlated with CD56bright/IL-10+/IL-4+ cells. There were no correlations in RPL. Conclusion, Recurrent pregnancy losses and implantation failures have lack of, or negative correlation between NCRs and intracellular cytokines expression. This observation suggests that excessive pro-inflammatory cytokine expression in NK cells in RPL and implantation failures may be exerted through the NCRs or interruption of signal transduction processes. [source]

    ORIGINAL ARTICLE: Women with Pre-Eclampsia Have an Altered NKG2A and NKG2C Receptor Expression on Peripheral Blood Natural Killer Cells

    AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 3 2009
    Nora Bachmayer
    Problem, Preeclampsia, a pregnancy disorder, is associated with exaggerated inflammation and increased serum monokines. Uterine natural killer (NK) cells are implicated in preeclampsia pathology, but little is known regarding peripheral NK cells in the disease. Method of Study, We examined blood NK cells at delivery in women with preeclampsia, in healthy pregnant women and in healthy non-pregnant blood donors as a reference. Results, Although the percentages of both NKG2A- and NKG2C-positive NK cells were normal in preeclamptic women, the levels of NKG2A and NKG2C on NK cells were significantly up-regulated in these women. In vitro stimulation of PBMCs from healthy pregnant women and blood donors with monokines resulted in increased percentage of NKG2A+ NK cells and increased NKG2A levels, while levels of NKG2C were decreased. Conclusions, Our results suggest that the peripheral NK-cell pool is skewed in preeclampsia and possibly under the influence of monokines like interleukin (IL)-15 and IL-12. [source]

    1141154113 Expression of natural cytotoxicity receptors in peripheral blood NK cell subsets of women with recurrent spontaneous abortions (RSA) or implantation failures

    AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 6 2006
    A Fukui
    Problem:, Natural Cytotoxicity Receptors (NCRs) are unique markers of NK cells and regulate NK cell cytotoxicity and cytokine production. a2V-ATPase is expressed in the cell membrane and can regulate the pH of the extracellular environment, which might facilitate NK cell killing or cytokine secretion. In this preliminary study we evaluated the expression of NCRs and a2V-ATPase in peripheral blood NK cells of women with RSA or implantation (IVF-ET) failures. Method of Study:, Peripheral blood was obtained from women with RSA (n = 10), or IVF-ET failures (n = 9). CD56dim and CD56bright NK cells were analyzed for the expression of NCRs (NKp46, NKp44 and NKp30) and a2V-ATPase using flow cytometry. Results:, For women with RSA, there were significant differences in the expression of NKp46 between CD56dim (36.9 ± 30.2) and CD56bright (76.0 ± 27.5) (P < 0.01), of NKp30 between CD56dim (30.9 ± 25.7) and CD56bright (55.8 ± 29.5) (P < 0.01), and of a2V-ATPase between CD56dim (1.0 ± 0.9) and CD56bright (23.2 ± 15.1) (P < 0.01) NK cells. For women with IVF-ET failures, there were significant differences in the expression of NKp46 between CD56dim (39.5 ± 21.5) and CD56bright (78.8 ± 26.0) (P < 0.01), of NKp30 between CD56dim (27.2 ± 17.9) and CD56bright (45.2 ± 29.8) (P < 0.05), and of a2V-ATPase between CD56dim (1.6 ± 1.4) and CD56bright (21.2 ± 16.5) (P < 0.01) NK cells. Conclusions:, The differential expression of NCRs and a2V-ATPase in NK cell subsets of women with RSA and IVF-ET failures may have an effect in cytotoxicity and cytokine production. Additional studies are currently in effect to evaluate these activities. We suggest that the analysis of NCRs and a2V-ATPase expression in peripheral blood NK cell subsets may contribute to a better understanding in the biology of NK cells in women with RSA or IVF-ET failures. [source]

    Maternal and Neonatal Lymphocyte Subpopulations at Delivery and 3 Days Postpartum: Increased Coexpression of CD45 Isoforms

    AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 1 2004
    Emilia Juretic
    Problem:, Huge physiologic changes during parturition involve immune cells. Alterations in maternal and neonatal lymphocytes postpartum might ascertain the subpopulations that are most affected and may possibly be of importance in the process. Method of study:, Peripheral blood was taken from 20 healthy women at vaginal delivery and 3 days later, concomitantly with cord and peripheral blood from their newborns. Lymphocyte immunophenotyping was done by three-color flow-cytometry. Results:, Maternal T helper cells were decreased and natural killer (NK) cells were significantly increased during labor. Percentage of CD4+ and percentage and absolute count of CD8+ cells coexpressing CD45RA and CD45RO antigens were higher than 3 days later. In cord blood NK cells were considerably increased and more CD4+ cells expressed CD45RO antigen. Conclusion:, Coexpression of CD45RA and CD45RO molecules indicates activation of maternal CD4+ and CD8+ lymphocytes. NK cells increase suggests their possible association with parturition processes. Lymphocyte subsets in cord blood correspond to maternal subsets to some extent. [source]