Lymphocyte Natural Killer Cell Research Articles

Circulating CD4+ T lymphocyte helper cells confer protection to reinfection of SARS-COV-2 but not circulating CD8+ T Lymphocyte natural killer cells

Circulating CD4+ T lymphocyte helper cells confer protection to reinfection of SARS-COV-2 but not circulating CD8+ T Lymphocyte natural killer cells

Transcriptome analysis of chicken intraepithelial lymphocyte natural killer cells infected with very virulent infectious bursal disease virus

The infectious bursal disease (IBD) is an acute immunosuppressive viral disease that significantly affects the economics of the poultry industry. The IBD virus (IBDV) was known to infect B lymphocytes and activate macrophage and T lymphocytes, but there are limited studies on the impact of IBDV infection on chicken intraepithelial lymphocyte natural killer (IEL-NK) cells. This study employed an mRNA sequencing approach to investigate the early regulation of gene expression patterns in chicken IEL-NK cells after infection with very virulent IBDV strain UPM0081. A total of 12,141 genes were expressed in uninfected chicken IEL-NK cells, and most of the genes with high expression were involved in the metabolic pathway, whereas most of the low expressed genes were involved in the cytokine-cytokine receptor pathway. A total of 1,266 genes were differentially expressed (DE) at 3 day-post-infection (dpi), and these DE genes were involved in inflammation, antiviral response and interferon stimulation. The innate immune response was activated as several genes involved in inflammation, antiviral response and recruitment of NK cells to the infected area were up-regulated. This is the first study to examine the whole transcriptome profile of chicken NK cells towards IBDV infection and provides better insight into the early immune response of chicken NK cells.

Identification of Reference Genes in Chicken Intraepithelial Lymphocyte Natural Killer Cells Infected with Very-virulent Infectious Bursal Disease Virus

Due to the limitations in the range of antibodies recognising avian viruses, quantitative real-time PCR (RT-qPCR) is still the most widely used method to evaluate the expression of immunologically related genes in avian viruses. The objective of this study was to identify suitable reference genes for mRNA expression analysis in chicken intraepithelial lymphocyte natural killer (IEL-NK) cells after infection with very-virulent infectious bursal disease virus (vvIBDV). Fifteen potential reference genes were selected based on the references available. The coefficient of variation percentage (CV%) and average count of these 15 genes were determined by NanoString technology for control and infected samples. The M and V values for shortlisted reference genes (ACTB, GAPDH, HMBS, HPRT1, SDHA, TUBB1 and YWHAZ) were calculated using geNorm and NormFinder. GAPDH, YWHAZ and HMBS were the most stably expressed genes. The expression levels of three innate immune response related target genes, CASP8, IL22 and TLR3, agreed in the NanoString and RNA sequencing (RNA-Seq) results using one or two reference genes for normalisation (not HMBS). In conclusion, GAPDH and YWHAZ could be used as reference genes for the normalisation of chicken IEL-NK cell gene responses to infection with vvIBDV.

The Role of Circulating CD16+CD56+ Natural Killer Cells in the Screening, Diagnosis, and Staging of Colorectal Cancer before Initial Treatment.

Background and Objective A reliable noninvasive prediction tool for the screening, diagnosis, and/or staging of colorectal cancer (CRC) before surgery is critical for the choice of treatment and prognosis. Methods Patients admitted for initial treatment of CRC between January 1, 2015, and December 31, 2018, were retrieved and reviewed. Records of CD16+CD56+ natural killer (NK) cells were analyzed according to the stages of CRC. Results The number of qualified participants in the healthy, stage I, stage II, stage III, and stage IV CRC patients were 60, 66, 60, 70, and 68, respectively. There was a significant difference in circulating CD16+CD56+ NK cells between the healthy group and the CRC group (p < 0.01), as well as between the healthy group and stage III or IV CRC group (p < 0.01 and 0.001, respectively). The percentage of circulating CD16+CD56+ NK cells in lymphocytes was negatively correlated with the occurrence of CRC. When comparing the pool of stage I and II CRC cases with the pool of stage III and IV CRC cases using circulating CD16+CD56+ NK cells, the area under the Receiver Operating Characteristic curve was 0.878. Using an optimal cutoff value of 15.6%, the OR was 0.06 (0.03, 0.11), p < 0.001, sensitivity was 86.5%, specificity was 72.5%, positive predictive value was 74.2%, and negative predictive value was 85.5%. Conclusions Circulating CD16+CD56+ NK cells can be used as a screening and diagnostic/staging tool for CRC.

The Development of Humanized Liver With Rag1 Knockout Rats

BackgroundThe animal model with humanized liver is useful for testing drug metabolism and toxicity in preclinical studies. A mouse model has been reported in which the liver was repopulated more than 90% with human hepatocytes; however, in the rat, the target is far from being reached. In this study, we attempt to develop a humanized liver model with an immunodeficient rat. MethodsRag1 knockout rats were treated with neonatal thymectomy. At 3 and 4 weeks of age, they were injected with hepatotoxin retrorsine; 2 weeks after, the animals were subjected to 70% partial hepatectomy and transplanted with immature human hepatocytes via portal vein. The recipients were also treated with anti-asialo GM1 antibody weekly from the day before transplantation and were injected with FK506 every 3 days after transplantation. ResultsIn Rag1 knockout rats, B lymphocytes were deleted almost completely in peripheral blood. However, T and natural killer (NK) lymphocytes were kept present. When they were treated additionally with neonatal thymectomy for T-lymphocyte deletion and suppressed neutralized NK lymphocytes with anti-asialo GM1, B, T, and NK cells in lymphocytes were reduced to very low levels of 0.75%, 1.58%, and 0.26%, respectively. After transplanting human donor hepatocytes into retrorsine-treated recipient livers, at week 3 the human cell-derived hepatic colonies were expanded in the recipient liver and the liver repopulation rate with human hepatocytes reached approximately 17%. The human hepatocyte-specific genes, albumin, CYP3A4, CYP2C18, and CYP2C9, also could be detected in the recipient rat. ConclusionIt is possible to generate a chimera animal with humanized liver in a novel severely immunodeficient rat model.

Role of Cellular Prion Proteins in the Function of Macrophages and Dendritic Cells

The cellular isoform of prion proteins (PrPC) is expressed in hematopoietic stem cells, granulocytes, T and B lymphocyte natural killer cells, platelets, monocytes, dendritic cells, and follicular dendritic cells, which may act as carrier cells for the spread of its abnormal isoform (PrPSc) before manifesting transmissible spongiform encephalopathies (TSEs). In particular, macrophages and dendritic cells seem to be involved in the replication of PrPSc after ingestion. In addition, information on the role of PrPC during phagocytotic activity in these cells has been obtained. A recent study showed that resident macrophages from ZrchI PrP gene (Prnp)-deficient (Prnp-/-) mice show augmented phagocytotic activity compared to Prnp+/+ counterparts. In contrast, our study suggests that Rikn Prnp-/- peritoneal macrophages show pseudopodium extension arrest and up-regulation of phagocytotic activity compared to Prnp+/+ cells. Although reports regarding phagocytotic activity in resident and peritoneal macrophages are inconsistent between ZrchI and Rikn Prnp-/- mice, it seems plausible that PrPC in macrophages could contribute to maintain the immunological environment. This review will introduce the recent progress in understanding the functions of PrPC in macrophages and dendritic cells under physiological conditions and its involvement in the pathogenesis of prion diseases.

A Peptide Against the N-Terminus of Myristoylated Alanine-Rich C Kinase Substrate Inhibits Degranulation of Human LeukocytesIn Vitro

Leukocytes synthesize a variety of inflammatory mediators that are packaged and stored in the cytoplasm within membrane-bound granules. Upon stimulation, the cells secrete the granule contents via an exocytotic process whereby the granules translocate to the cell periphery, the granule membranes fuse with the plasma membrane, and the granule contents are released extracellularly. We have reported previously that another exocytotic process, release of mucin by secretory cells of the airway epithelium, is regulated by the myristoylated alanine-rich C kinase substrate (MARCKS) (Li Y, Martin LD, Spizz G, Adler KB. MARCKS protein is a key molecule regulating mucin secretion by human airway epithelial cells in vitro. J Biol Chem 2001;276:40982-40990; Singer M, Martin LD, Vargaftig BB, Park J, Gruber AD, Li Y, Adler KB. A MARCKS-related peptide blocks mucus hypersecretion in a mouse model of asthma. Nat Med 2004;10:193-196). In those studies, mucin secretion in vitro and in vivo was attenuated by a synthetic peptide identical to the N-terminus of MARCKS, named the MANS peptide (Li and colleagues, 2001). In this study, we used the MANS peptide to investigate possible involvement of MARCKS in secretion of leukocyte granule proteins. In neutrophils isolated from human blood, phorbol 12-myristate 13-acetate-induced myeloperoxidase release was attenuated in a concentration-dependent manner by MANS but not by equal concentrations of a missense control peptide. In additional studies using human leukocyte cell lines, secretion of eosinophil peroxidase from the eosinophil-like cell line HL-60 clone 15, lysozyme from the monocytic leukemia cell line U937, and granzyme from the lymphocyte natural killer cell line NK-92 were attenuated by preincubation of the cells with MANS but not with the missense control peptide. The results indicate that MARCKS protein may play an important role in the secretion of membrane-bound granules from different leukocytes. MARCKS may be an important component of secretory pathways associated with release of granules by different cell types.

Acute effects of electroconvulsive therapy on lymphocyte natural killer cell activity in patients with major depression

Background: Major depression has been associated with a reduction in lymphocyte natural killer cell activity (NKCA). The effects of biological treatment of depression on the immune system have not been systematically investigated. The present study addresses the acute effects of electroconvulsive therapy (ECT) on NKCA. Methods: Thirteen patients undergoing ECT for major depression were studied. NKCA at four different effector:target (E:T) ratios (E:T=50:1; 25:1; 12.5:1 and 6.25:1, respectively) was assessed serially in relation to the first ECT session prior to and up to 1 h following treatment (−30′, −10′, −3′ before ECT and +3′, +10′, +30′ and +60′ following ECT). On several patients, NKCA data were also available in relation to the sixth ECT session. Comparisons between mean NKCA values for each of the E:T ratios at the different time points were made using ANOVA. Results: There were significant changes in NKCA values with time at E:T=25:1 ( P<0.05). Mean NKCA values for the 30 min following ECT were significantly higher than the mean NKCA values for the 30 min preceding ECT for all four E:T ratios used ( P<0.05). Differences in NKCA values between ECT no. 1 and ECT no. 6 were small and not statistically significant. Conclusion: ECT is associated with a significant albeit transient increase in NKCA. The clinical implications of these findings are unknown at the present time. Limitations: A small number of patients has been investigated, particularly for the sixth ECT session. No control group for ECT was available. No correlations with clinical outcome variables have been obtained.

The ratio of n-6 to n-3 polyunsaturated fatty acids in the rat diet alters serum lipid levels and lymphocyte functions.

Previous studies have reported that feeding rats diets rich in fish oils, which contain high proportions of the n-3 polyunsaturated fatty acids (PUFA) eicosapentaenoic and docosahexaenoic acids, results in lowering of blood lipid levels and suppression of lymphocyte functions tested ex vivo and in vivo. The effects of other n-3 PUFA, such as alpha-linolenic acid, which is found in high proportions in linseed oil, are not as well documented. Therefore, in the present study, weanling male rats were fed for six weeks on one of five high-fat (20% by weight) diets made by mixing together sunflower and linseed oils; the resulting blends had n-6/n-3 PUFA ratios of 112.5:1 (pure sunflower oil), 14.8:1, 6.5:1, 0.81:1, and 0.33:1 (pure linseed oil); the levels of all other components in the diet were identical. The final body weight and total dissectable fat were lowest in rats fed the pure linseed oil diet. Serum cholesterol, triacylglycerol and nonesterified fatty acid concentrations decreased as the n-6/n-3 PUFA ratio of the diet decreased. The fatty acid composition of the serum and of spleen lymphocytes was influenced by the diet fed-there was a progressive decrease in the proportions of linoleic and arachidonic acids and a progressive increase in the proportion of alpha-linolenic acid as the n-6/n-3 PUFA ratio of the diet decreased. Eicosapentaenoic and docosahexaenoic acids were detected in the serum but not in spleen lymphocytes. Inclusion of alpha-linolenic acid in the diet resulted in significant suppression of spleen lymphocyte proliferation in response to the T-cell mitogen concanavalin A and in spleen lymphocyte natural killer cell activity, both measured ex vivo. The localized graft vs. host response, a measure of cell-mediated immunity in vivo, progressively decreased as the n-6/n-3 PUFA ratio of the diet decreased. Thus, this study shows that dietary alpha-linolenic acid results in lowered blood lipid levels and suppressed lymphocyte functions ex vivo and in vivo. With respect to these effects, alpha-linolenic acid is as potent as dietary fish oil.

Effects of haloperidol on lymphocyte natural killer cell activity: in vivo and in vitro studies : Ziad Kronfol, Madhavan Nair, James Meador-Woodruff University of Michigan Medical Center, Ann Arbor, MI 48109-0118

Effects of haloperidol on lymphocyte natural killer cell activity: in vivo and in vitro studies : Ziad Kronfol, Madhavan Nair, James Meador-Woodruff University of Michigan Medical Center, Ann Arbor, MI 48109-0118

Enhancement of human natural killer cell activity by opioid peptides: Similar response to methionine-enkephalin and β-endorphin

We studied the effect of methionine-enkephalin (MET) and β-endorphin upon human peripheral blood lymphocyte natural killer cell (NKC) activity in a group of healthy volunteers ( n = 27; 17 male and 10 female, age ± SD and range of 32 ± 6, 25–43 years and 36 ± 11, 22–65 years, respectively). Aliquots from some individual samples were preincubated separately with different concentrations of either peptide ( n = 12), while others were tested with only one of these substances (MET, n = 6; β-endorphin, n = 9). Using each individual as its own control, MET (10 −8 and 10 −6 M) and β-endorphin (10 −10 and 10 −8 M) significantly increased NKC activity (NKCA) (at least 20% over base value, effector-to-target cell ratio, 40:1) in 7 out of 15 and 7 out of 19 subjects, respectively. Results obtained from the rest of the samples were mixed, e.g., changes observed in NKCA were not significant or showed significance with only one of the peptide concentrations studied. Cells from individuals showing a significant increase in NKC lytic function following preincubation with either MET or β-endorphin responded similarly to the other peptide (in both cases 5 out of 6 subjects), suggesting that enhancement of NKCA by MET and β-endorphin may work through a similar mechanism.

A familial occurrence of natural killer cell-T-lymphocyte proliferation disease in two children

Several reports describe the association of hyperlymphocytosis with neutropenia. This syndrome, named lymphoproliferative disease, is characterized by a chronic indolent clinical course, bone marrow lymphocyte infiltration, and granulopenia of central origin. The proliferating lymphocytes share large granular lymphocyte natural killer cell and T-lymphocyte characteristics. They are either of monoclonal or polyclonal origin. In this report the familial occurrence of a similar syndrome observed in two children is described. Lymphocyte morphologic abnormalities including nuclear pockets, were noted, a feature usually present in leukemic cells. Lymphocyte proliferation was distinct in each case as shown by the presence of a predominant CD4+ cell population in one and a predominant CD8+ population in the other. Monoclonal gene rearrangements of T-cell receptor beta-chain gene were found although clonal variations occurred with time in one patient. The cause of this unique familial occurrence of monoclonal lymphoproliferation associated with neutropenia is unknown.

Fifty cases of human immunodeficiency virus (HIV) infection: immunoultrastructural study of circulating lymphocytes.

The peripheral lymphocytes of 50 cases of human immunodeficiency virus (HIV) infection (13 of acquired immune deficiency syndrome (AIDS), 17 of AIDS related complex (ARC), and 20 healthy carriers) were studied immunoultrastructurally. The prevalence of "tubuloreticular structures" and "tubular confronting cisternae" increased with the progression of the disease. Numerous tubular confronting cisternae were noted in patients presenting with a high serum acid labile alpha-interferon values. The patients with depressed natural killer cell activity were characterised by circulating immature natural killer cells with abundant multivesicular bodies that were devoid of "parallel tubular arrays". With an immunogold staining technique the location of HIV antigen was detected ultrastructurally, both at the surface of "hand-mirror" natural killer cell lymphocytes and inside vacuolised cells, probably corresponding to infected T4 lymphocytes. These findings indicate the usefulness of electron microscopic techniques in evaluating the pathology and the pathogenetic outcome of AIDS.

Association between urinary zinc excretion and lymphocyte dysfunction in patients with lung cancer

Patients with bronchogenic carcinoma often have low serum zinc concentrations and sometimes have markedly elevated renal zinc losses. Since normal zinc metabolism is critical for the proper function of T lymphocytes and natural killer cells, the effect of zinc status on T cell phytohemagglutinin response and peripheral blood lymphocyte natural killer cell activity was studied in patients with lung cancer. Mean (± SEM) serum zinc concentration in 75 patients with cancer was 67.4 ± 2.2 μg/dl versus 96.0 ± 8.0 μg/dl for normal subjects. Patients with low serum zinc levels (less than 70 μg/dl) had significantly higher urine zinc excretion than patients with normal serum zinc levels (1,385 ± 240 μg per 24 hours versus 392 ± 107 μg per 24 hours) (p <0.001). This pattern of zinc concentrations (i.e., low serum zinc in combination with high urine zinc) is typical of patients with mild zinc deficiency, and suggests that a mild chronic zinc deficiency state was present in some of these patients. When lymphocyte data were analyzed according to serum zinc concentrations and urinary zinc excretion, low serum zinc concentration and high urine zinc excretion both correlated with depressed T cell phytohemagglutinin response (p <0.005 and p <0.001, respectively). For instance, mean maximal phytohemagglutinin response in patients with urinary zinc excretion of more than 700 μg per 24 hours was 22,132 ± 3,201 cpm (n = 14) compared with 68,130 ± 6,850 cpm for patients with normal zinc excretion (n = 7). Peripheral blood lymphocyte natural killer cell activity did not correlate with either serum or urine zinc values. Oral zinc sulfate (220 mg, three times daily for six weeks) was then administered to patients with hyperzincuria (mean = 992 μg per 24 hours). Zinc-supplemented patients had normalization of T cell phytohemagglutinin response after zinc therapy, whereas control patients demonstrated continued T cell dysfunction. Natural killer cell activity did not change in either group during the study period. These data suggest that a mild subclinical zinc deficiency state may exist in some patients with lung cancer and may be an important cause of abnormal T cell function. Furthermore, zinc supplementation may be useful to improve lymphocyte function in selected patients. Whether zinc supplementation would alter the course of the disease or the patient's prognosis is presently unknown.

Impaired natural killer cell activity in patients with inflammatory bowel disease: Evidence for a qualitative defect

The natural killer cell lymphocyte may represent an important element in immune defense. Since host defense may be abnormal in patients with inflammatory bowel disease, we assessed natural killer cell function in 34 patients with ulcerative colitis and Crohn's disease. Lymphocytes from 31 of 34 patients (91%) exhibited decreased natural killer cell activity (mean cytotoxicity ± SEM was 25% ± 7.5% of the mean normal values, p < 0.01). Disease activity, type of disease, and steroid therapy had no influence on these values. None of the 10 age-matched disease controls with other intestinal inflammatory conditions had natural killer cell activity outside the normal range. The numbers of circulating killer cells present in patients with impaired activity were quantified using a cytofluorometric detection system. All patients tested had normal numbers of cells binding nonaggregated immunoglobulin G (Fc receptor positive) despite decreased natural killer cell activity. It appears that by using this cytofluorometric detection technique, decreased natural killer cell activity is not the consequence of diminished numbers of natural killer cells.