Natural killer lymphocytes

Studies of the effects of in vitro exposure to a range of concentrations (encompassing environmentally relevant concentrations of monobutyltin, dibutyltin, and tributyltin) on human natural killer lymphocytes obtained from adult male and female donors revealed the presence of detectable concentrations of the butyltins in all the donors, indicating possible exposure of natural killer cells to butyltins in the blood. It was suggested that the study provided evidence that butyltin compounds significantly inhibit natural killer cell function and possible natural killer cell-mediated potential in humans (Whalen etal, 1999). 

Adult bone marrow-derived stem cells are presently the cell types most widely utilized in cardiac stem cell therapy. A heterogeneous subset, termed autologous bone marrow-derived mononuclear cells (ABMMNCs), is composed of small amounts of stromal or MSCs, HPCs, EPCs, and more committed cell lineages, such as natural killer lymphocytes, T lymphocytes, B lymphocytes, and others [2]. 

Approximately 30% of liver cells are nonparenchymal cells. Cell types located in the interlobular portal tracts include bile duct epithelial cells and connective tissue fibroblasts. Those located within the lobule interior are the rare fixed, natural killer lymphocytes (pit cells) and the more abundant endothelial cells lining the sinusoids, Kupffer cells, and stellate cells (also known as fat-storing or Ito cells). The recent... 

Shavit Y, Terman GW, Lewis JW, Zane CJ, Gale RP, Liebeskind JC (1986b) Effects of footshock stress and morphine on natural killer lymphocytes in rats Studies of tolerance and cross-tolerance. Brain Res 372 382-385. 

The mechanism by which IFN-a exerts antitumor activity is unclear, particularly in hematological cancers. In melanoma and renal cell carcinoma, antitumor effects may be mediated by augmented immune responses including activation of natural killer lymphocytes and enhanced expression of cell surface antigens (e.g., MHC I and II). However, these mechanisms have not been decisively proved. 

Azathioprine, 6-(l-methyl-4-nitro-imidazole-5-yl)-thiopurine (see Figure 1), is an immunosuppressive agent [1,2], which is widely used in clinical treatment of autoimmune disorders as weU as in prevention of graft rejection or graft-versus-host disease in organ and tissue transplantation [3-10], Azathioprine acts on several activities in cellular immunity processes. It inhibits lymphocyte activation [11], lymphocyte differentiation [12], in-vitro lymphocyte stimulation [13,14], in-vitro mixed lymphocyte reaction [15] and it reduces the activity of natural killer lymphocytes [16,17],... 

Little is known about the effects of organotins in humans. What is known was reviewed in 2001. Thymocytes play an important role in human immunity 24 h after exposure in vitro to 500 ng of a variety of mono, di, and tributyltin compounds, the viability of thymocytes was halved. The natural-killer lymphocytes were affected by the presence of these butyltin compounds at a concentration of about 200 nM after 24 h. ... 

COPD is a chronic inflammatory disease that results from prolonged and repeated inhalation of particles and gases, chronic (or latent) infection or an interaction of these factors. In many cases, the inflammation persists even when the exposure (in most cases smoking) is stopped. Prominent among the infiltrating leukocytes are neutrophils, CD8+ lymphocytes (Co-receptor for the T-cell receptor. CD8+ is specific for the class IMHC protein. It is expressed on the surface of cytotoxic T-cells and natural killer cells.) and CD68+ monocytic cells (A lysosomal antigen. All cells that rich in... 

Immune Defense. Figure 2 Cytokines involved in the development of adaptive immune responses in secondary lympoid tissues such as the lymph nodes or spleen. Abbreviations B B-lymphocyte, IFN interferon, Ig immunoglobulin, IL interleukin, NK natural killer cell, TE T-effector (cytotoxic) lymphocyte, TH T-helper lymphocyte... 

Large granular lymphocytes, not belonging to either the T- or B-cell lineage. Natural killer (NK) cells are considered part of the innate defense system since, in contrast to cytotoxic T-cells, they are able to kill certain tumor cells in vitro without prior sensitization. The basal activity of NIC cells increases dramatically following stimulation with type I IFNs. In addition, NK cells display Fc-receptors for IgG and are important mediators of Antibody-Dependent-Cell-mediated-Cytotoxicity (ADCC). 

Syk and ZAP-70 are early intermediates in the transduction of signals from immune receptors, including the B- and T-cell recqrtors for antigen, activatory natural killer-cell receptors, the mast cell and basophil receptor for IgE, and the widely distributed receptors for the Fc portion of IgG. Immune receptors control checkpoints in lymphocyte development and serve to integrate the responses of innate and acquired immunity. 

Natural killer cell Lymphocytes Rat (prenatal and lactation exposure) Yes Reduced 42% Ilback et al. (1991)... 

IL-1 (17.5) Monocyte/macrophage, lymphocyte, neutrophil, endothelium, fibroblast keratinocyte Activation of T cells, B cells, natural killer cells, osteoblasts, and endothelium. Induces fever, sleep, anorexia, ACTH release, hepatic acute phase protein synthesis and HSPs. Leads to myocardial depression, hypercoagulability, hypotension/sbock, and death. Simulates production of TNF, IL-6, and IL-8 and stress hormone release. Suppression of cytochrome P-450, thyro-globulin, and lipoprotein synthesis. Procoagulant activity. Antiviral activity. 

The CB2 receptor has a more limited distribution, being localized predominantly in the immune system. Among the human leukocytes, B lymphocytes express the highest levels of CB2, followed respectively by natural killer cells, monocytes, polymorphonuclear neutrophils, T8 lymphocytes, and T4 lymphocytes. It is also found in the lymph nodes, spleen, tonsils, and thymus (Cabral, 1999). 

Kimber I, Jackson JA, Stonard MD. 1986a. Failure of inorganic lead exposure to impair natural killer (NK) cell and T-lymphocyte function in rats. Toxicol Lett 31 211-218. 

Kimura, A., Orn, A., Holmquist, G., Wizzell, H., and Ersson, B. (1979) Unique lectin-binding characteristics of cytotoxic T-lymphocytes allowing their distribution from natural killer cells and K cells. Eur. J. Immunol. 9, 575. 

Null cells are also known as large granular lymphocytes , but are best known as natural killer (NK) cells. These represent a third lymphocyte subgroup. They are capable of directly lysing cancer cells and virally infected cells. 

Pasqualetti, D. et al., Lymphocyte T subsets and natural killer cells in Italian and Philippino blood donors, Vox Sang., 84, 68, 2003. 

Based upon recent controlled studies, there is considerable evidence that opioids such as morphine induce substantial effects on immune status. For example, it has been shown that morphine administration is associated with alterations in a number of immune parameters, such as natural-killer cell activity [12,13], proliferation of lymphocytes, [13, 14] antibody production [15,16], and the production of interferon [17]. Studies in our laboratory have shown that acute morphine treatment in rats suppresses splenic lymphocyte proliferative responses to both T- and B-cell mitogens, splenic natural-killer cell activity, blood lymphocyte mitogenic responsiveness to T-cell mitogens, and the in vitro production of the cytokines interleukin-2 and interferon-y [18-22], Furthermore, the immune alterations induced by morphine are dose-dependent and antagonized by the opioid-receptor antagonist, naltrexone (e.g., [22]). 

Novick, D.M. et al., Natural killer cell activity and lymphocyte subsets in parenteral heroin abusers and long-term methadone maintenance patients, J. Pharmacol. Exp. Ther., 250, 606, 1989. 

Kay, N., Allen, J., Morley, J.E., Endorphins stimulate normal human peripheral blood lymphocyte natural killer activity, Life Sci., 35, 53, 1984. 

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