Natural Cytotoxic Activity Research Articles

Engineering of CD34+ progenitor-derived natural killer cells with higher-affinity CD16a for enhanced antibody-dependent cellular cytotoxicity

Background aimsNatural killer (NK) cell transfer is a promising cellular immunotherapy for cancer. Previously, we developed a robust method to generate large NK cell numbers from CD34+ hematopoietic stem and progenitor cells (HSPCs), which exhibit strong anti-tumor activity. However, since these cells express low levels of the Fc receptor CD16a in vitro, antibody-dependent cellular cytotoxicity (ADCC) by these cells is limited. To broaden clinical applicability of our HSPC-NK cells toward less NK-sensitive malignancies, we aimed to improve ADCC through CD16a transduction. MethodsUsing wildtype and S197P mutant greater-affinity (both with V158) CD16a retroviral transgenes (i.e., a cleavable and noncleavable CD16a upon stimulation), we generated CD16a HSPC-transduced NK cells, with CD34+ cells isolated from umbilical cord blood (UCB) or peripheral blood after G-CSF stem cell mobilization (MPB). CD16a expressing NK cells were enriched using flow cytometry–based cell sorting. Subsequently, phenotypic analyses and functional assays were performed to investigate natural cytotoxicity and ADCC activity. ResultsMean transduction efficiency was 34% for UCB-derived HSPCs and 20% for MPB-derived HSPCs, which was enriched by flow cytometry-based cell sorting to >90% for both conditions. Expression of the transgene remained stable during the entire NK expansion cell generation process. Proliferation and differentiation of HSPCs were not hampered by the transduction process, resulting in effectively differentiated CD56+ NK cells after 5 weeks. Activation of the HSPC-derived NK cells resulted in significant shedding of wildtype CD16a transcribed from the endogenous gene, but not of the noncleavable mutant CD16a protein expressed from the transduced construct. The mean increase of CD107+IFNγ+ expressing NK cells after inducing ADCC was tenfold in enriched noncleavable CD16a HSPC-NK cells. Killing capacity of CD16a-transduced NK cells was significantly improved after addition of a tumor-targeting antibody in tumor cell lines and primary B-cell leukemia and lymphoma cells compared to unmodified HSPC-NK cells. ConclusionsTogether, these data demonstrate that the applicability of adoptive NK cell immunotherapy may be broadened to less NK-sensitive malignancies by upregulation of CD16a expression in combination with the use of tumor-targeting monoclonal antibodies.

Classification of NK-Large Granular Lymphocytic Leukemia By CD56 Expression

Introduction Large granular lymphocytic leukemia (LGLL) is a rare chronic lymphoproliferative disease of T cell and natural killer (NK) cell lineage. Less than 10% of cases are NK-large granular lymphocytic leukemia (NK-LGLL), which is distinguished by clonal growth of mature NK cells that are CD3-, CD16+, and/or CD56+. There are two types of mature NK cells based on CD56 intensity. The CD56dim NK-cell subset exhibits a higher level of natural cytotoxic activity compared to the CD56bright NK-cell subset, which, in turn, is capable of producing abundant cytokines ( Trends Immunol. 2001;22(11):633-640). However, few studies have explored the internal heterogeneity of NK-LGLL based on CD56 expression ( Leukemia. 2010;24(4):881-884; Blood Cancer J. 2018;8(6):51) . Method A total of 402 patients have been diagnosed with LGLL at our hospital since June 2005, including 40 with NK-LGLL. All patients met the recommended diagnostic criteria ( Blood. 2017;129(9):1082-1094). Treatment responses were collected after at least 3 months of therapy. NK subtype was defined by flow cytometry analysis using common surface markers showing CD3−/CD16+, or CD56+ pattern, and cells were considered antigen partial positive if antibody staining was between 20%-80%. To perform subgroup analysis, we incorporated partial CD56 positive into the negative group since mature NK cells are CD56-positive. Clonality was evaluated by killer-cell immunoglobulin-like receptors (KIR). Sequencing of STAT3 and STAT5b was performed with Next Generation Sequencing. Results Twenty-eight of 40 patients (70.0%) presented symptoms at the time of diagnosis in which anemia was the most prevalent accounting for 67.5%. PRCA was the most common comorbidity, affecting 20.0% of patients. All cases were CD2+, CD3-. Expressions of mature NK cell markers are heterogenous, including CD8 (22.5%), CD16 (77.5%), CD56 (40.0%), CD57 (58.9%), CD94 (78.8%), CD161 (35.3%), perforin (83.3%), GramB (77.8%). KIR analyses were available in 31 cases, 45.2% of NK-LGLs showed a form of restrictive expression, mainly CD158i (32.3%), an activating KIR, whereas 58.1% of cases lacked CD158a/b/e/f/i expression. STAT3 mutated status was studied in 28 cases (70.0%), 46.4% had STAT3 mutations, and no STAT5B mutations were detected. We classified 40 cases into two subsets based on CD56 expression (Table 1). CD56- cases displayed a more aggressive course. They usually presented with symptomatic disease including anemia (91.7% vs 31.3%, P= 0.000), severe anemia (66.7% vs 12.5%, P= 0.001), neutropenia (66.7% vs 12.5%, P= 0.001), splenomegaly (52.4% vs 12.5%, P= 0.012), and treatment requirement (87.0% vs 31.3%, P= 0.001). CD56-negative cases expressed CD161 at a higher frequency (60.0% vs 0.0%, P=0.001) while the other mature markers were similar. Interestingly, STAT3 mutation was detected in 13 of 20 (65.0%) in CD56- NK-LGLL, and none of 8 CD56+ NK-LGLL had STAT3 mutation (p=0.007). The treatment pattern was similar between CD56+ vs CD56- NK-LGLL. However, the treatment efficacy was lower in CD56- NK-LGLL, with overall response rates (ORR) of 100% vs 79% and CR (complete response) rate of 80% vs 46%, in CD56+ and CD56- NK-LGLL patients respectively. Conclusions NK-LGLL is a heterogenous entity and can be divided into two groups further based on CD56 expression. CD56- NK-LGLL showed more prominent clinical symptoms, high STAT3 mutation, and CD161 expression. CD56- NK-LGLL showed a poor response than CD56+ NK-LGLL. More investigations are deserved to explore the underlying mechanisms.

Diversity and Biological Activities of Endophytic Fungi from the Flowers of the Medicinal Plant Vernonia anthelmintica.

Secondary metabolites produced by endophytic fungi are an important source of biologically active compounds. The current research was focused on the biological activities of ethyl acetate extracts of fungi, isolated and identified from Vernonia anthelmintica flowers for the first time. In addition, an investigation of the non-polar chemical composition of dichloromethane-ethyl acetate extracts of the most active fungal strain was carried out. The isolates included Ovatospora senegalensis NR-03, Chaetomium globosum NR-04, Thielavia subthermophila NR-06, Aspergillus calidoustus NR-10, Aspergillus keveii XJF-23 and Aspergillus terreus XJF-3 species. Strains were identified by 18S rRNA gene sequencing methods and were registered in GenBank. Crude extracts of the fungi displayed in vitro biological activities, including antimicrobial and cytotoxic activities. A melanin content assay was performed on murine B16 cells. An ethyl acetate extract of O. senegalensis NR-03 showed high anticancer and antimicrobial activity; therefore, we also studied the non-polar chemical composition of the dichloromethane-ethyl acetate fraction and identified 52 non-polar compounds with the different medium. This investigation discovered that the secondary metabolites of the total extract of endophytic fungi could be a potential source of alternative natural antimicrobial, cytotoxic and melanin synthesis activity in their host plant, and the isolation of bioactive metabolites may provide a lead to new compounds of pharmaceutical significance.

Heme oxygenase and indoleamine regulation by cytokines in cervical cancer cells and natural killer cells cytotoxic activity

Heme oxygenase and indoleamine regulation by cytokines in cervical cancer cells and natural killer cells cytotoxic activity

CircFOXO3 Induced by KLF16 Modulates Clear Cell Renal Cell Carcinoma Growth and Natural Killer Cell Cytotoxic Activity through Sponging miR-29a-3p and miR-122-5p.

Renal cell carcinoma (RCC) is one of the most common urological malignancies with high incidence and metastatic relapse. Clear cell RCC (ccRCC) comprises nearly 70% of all RCC cases and is responsible for the majority of morbidity and mortality of RCC. Due to the poor diagnosis strategy and unsatisfactory clinical intervention, ccRCC causes a huge economic burden and poor patient quality of life; therefore, novel diagnostic or therapeutic targets for ccRCC are urgently needed. This study investigated the biological role of circFOXO3 in ccRCC development, showing that circFOXO3 is highly expressed in RCC cells and tissues and inhibits the viability of ccRCC cells. circFOXO3 dysregulation regulates NK cell cytotoxicity towards RCC cells by directly sponging miR-29a-3p and miR-122-5p. Overexpression of miR-29a-3p or miR-122-5p attenuated NK cell toxicity towards RCC cells and the transcriptional factor Kruppel-Like Factor 16 (KLF16) regulates circFOXO3 expression in RCC cells. In conclusion, this study has partially elucidated the function of circFOXO3 in ccRCC development, providing potential novel therapeutic targets for ccRCC.

Peritoneal Fluid from Patients with Ovarian Endometriosis Displays Immunosuppressive Potential and Stimulates Th2 Response.

Endometriosis is a common gynaecological disorder characterized by the ectopic growth of endometrial tissue outside the uterine cavity. It is associated with chronic pelvic inflammation and autoimmune reactivity manifesting by autoantibody production and abrogated cellular immune responses. Endometriotic peritoneal fluid contains various infiltrating leucocyte populations and a bulk of proinflammatory and immunoregulatory cytokines. However, the nature and significance of the peritoneal milieu in women with endometriosis still remains obscure. Therefore, the aim of the present study was to investigate the immunoregulatory activity of the peritoneal fluid (PF) from women with endometriosis. The peritoneal fluid samples were collected during laparoscopic surgery from 30 women with and without endometriosis. Immunoregulatory cytokines (IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-γ and TNF) and chemokines (CCL2, CCL5, CXCL8 and CXCL9) were evaluated in PF and culture supernatants generated by unstimulated and CD3/CD28/IL-2-stimulated CD4+ T cells cultured in the presence of PF. The effect of PF on the generation of Treg and Th17 cells in CD4+ T cell cultures, as well as the natural cytotoxic activity of peripheral blood mononuclear cells, was also investigated. Concentrations of IL-6, IL-10, CCL2, CXCL8 and CXCL9 were significantly upregulated in the PF from women with endometriosis when compared to control women, whereas concentrations of other cytokines and chemokines were unaffected. The culturing of unstimulated and CD3/CD28/IL-2-stimulated CD4+ T cells in the presence of endometriotic PF resulted in the downregulation of their IL-2, IFN-γ, IL-17A and TNF production as compared to culture medium alone. On the other side, endometriotic PF significantly stimulated the production of IL-4 and IL-10. Endometriotic PF also stimulated the release of CCL2 and CXCL8, whereas the production of CCL5 and CXCL9 was downregulated. Endometriotic PF stimulated the generation of Treg cells and had an inhibitory effect on the generation of Th17 cells in cultures of CD4+ T cells. It also inhibited the NK cell cytotoxic activity of the peripheral blood lymphocytes. These results strongly imply that the PF from patients with endometriosis has immunoregulatory/immunosuppressive activity and shifts the Th1/Th2 cytokine balance toward the Th2 response, which may account for deviation of local and systemic immune responses. However, a similar trend, albeit not a statistically significant one, was also observed in case of PF from women without endometriosis, thus suggesting that peritoneal milieu may in general display some immunoregulatory/immunosuppressive properties. It should be stressed, however, that our present observations were made on a relatively small number of PF samples and further studies are needed to reveal possible mechanism(s) responsible for this phenomenon.

Chimeric Virus-Like Particles of Prawn Nodavirus Displaying Hepatitis B Virus Immunodominant Region: Biophysical Properties and Cytokine Response.

Hepatitis B is a major global health challenge. In the absence of an effective treatment for the disease, hepatitis B vaccines provide protection against the viral infection. However, some individuals do not have positive immune responses after being vaccinated with the hepatitis B vaccines available in the market. Thus, it is important to develop a more protective vaccine. Previously, we showed that hepatitis B virus (HBV) ‘a’ determinant (aD) displayed on the prawn nodavirus capsid (Nc) and expressed in Spodoptera frugiperda (Sf9) cells (namely, Nc-aD-Sf9) self-assembled into virus-like particles (VLPs). Immunisation of BALB/c mice with the Nc-aD-Sf9 VLPs showed significant induction of humoral, cellular and memory B-cell immunity. In the present study, the biophysical properties of the Nc-aD-Sf9 VLPs were studied using dynamic light scattering (DLS) and circular dichroism (CD) spectroscopy. Enzyme-linked immunosorbent assay (ELISA) was used to determine the antigenicity of the Nc-aD-Sf9 VLPs, and multiplex ELISA was employed to quantify the cytokine response induced by the VLPs administered intramuscularly into BALB/c mice (n = 8). CD spectroscopy of Nc-aD-Sf9 VLPs showed that the secondary structure of the VLPs predominantly consisted of beta (β)-sheets (44.8%), and they were thermally stable up to ~52 °C. ELISA revealed that the aD epitope of the VLPs was significantly antigenic to anti-HBV surface antigen (HBsAg) antibodies. In addition, multiplex ELISA of serum samples from the vaccinated mice showed a significant induction (p < 0.001) of IFN-γ, IL-4, IL-5, IL-6, IL-10, and IL-12p70. This cytokine profile is indicative of natural killer cell, macrophage, dendritic cell and cytotoxic T-lymphocyte activities, which suggests a prophylactic innate and adaptive cellular immune response mediated by Nc-aD-Sf9 VLPs. Interestingly, Nc-aD-Sf9 induced a more robust release of the aforementioned cytokines than that of Nc-aD VLPs produced in Escherichia coli and a commercially used hepatitis B vaccine. Overall, Nc-aD-Sf9 VLPs are thermally stable and significantly antigenic, demonstrating their potential as an HBV vaccine candidate.

Vitamin D and the Immune System in Menopause: A Review.

Menopause is a normal phenomenon in a woman’s life cycle involving multiple health-related issues that contribute to physical instability. Changes in the immune system in postmenopausal women are caused by estrogen deprivation along with age. Increased proinflammatory serum marker levels, cytokine responses in body cells, decreased CD4 T and B lymphocyte levels, and natural killer cell cytotoxic activity are also observed during postmenopause. Moreover, vitamin D, in addition to its classical effects on calcium homeostasis and bone density, plays an important role. Current evidence indicates that vitamin D regulates innate and adaptive immune responses; however, vitamin D deficiency is linked to increased autoimmune activity and infection susceptibility. This review provides an overview of the consequences of immune alterations as an outcome of aging in postmenopausal women and the benefit of vitamin D supplementation.

The effect of human leukocyte antigen A1 and B35-Cw4 on sustained BK polyomavirus DNAemia after renal transplantation.

Human leukocyte antigen (HLA) class I presentation pathway plays a central role in natural killer (NK) cell and cytotoxic T-cell activities against BK polyomavirus (BKPyV) DNAemia. We determined the risk of sustained BKPyV DNAemia in 175 consecutive renal transplant recipients considering the simultaneous effect of donor/recipient HLA class I antigens and pre- or post-transplant variables. Median (IQR) age was 53 (44-64) years, and 37% of patients were female. 40 patients (22.9%) developed sustained BKPyV DNAemia [median (IQR) viral load: 9740 (4350-17125) copies/ml]. In the Cox proportional hazard analysis, HLA-A1 (HR: 3.06, 95% CI: 1.51-6.17) and HLA-B35-Cw4 (HR: 4.63, 95% CI: 2.12-10.14) significantly increased the risk of sustained BKPyV DNAemia, while 2 HLA-C mismatches provided a marginally protective effect (HR: 0.32, 95% CI: 0.10-0.98). HLA-Cw4 is a ligand for NK cell inhibitory receptor, and HLA-B35 is in strong linkage disequilibrium with the HLA-Cw4 allele. The association between HLA-B35-Cw4 expression and sustained BKPyV DNAemia supports the important role of cytotoxic T cells and NK cells that would normally control BKPyV activation through engagement with immunoglobulin-like killerreceptors(KIRs). Further studies are required to investigate the effect of HLA-C alleles along with NK cell activity against BKPyV DNAemia.

Multifaceted Applications of Microbial Pigments: Current Knowledge, Challenges and Future Directions for Public Health Implications.

Microbial oddities such as versatile pigments are gaining more attention in current research due to their widely perceived applications as natural food colorants, textiles, antimicrobial activities, and cytotoxic activities. This indicates that the future generation will depend on microbial pigments over synthetic colorants for sustainable livelihood. Although several reviews have detailed the comprehensive applications of microbial pigments extensively, knowledge on several aspects of pigmented microbes is apparently missing and not properly reviewed anywhere. Thus, this review has been made to provide overall knowledge on biodiversity, distribution, pathogenicity, and ecological and industrial applications of microbial pigments as well as their challenges and future directions for food, industrial, and biomedical applications. Meticulously, this compendious review treatise on the pigments from bacteria, fungi, yeasts, and microalgae includes reports from the 1970s to 2018. A total of 261 pigment compounds produced by about 500 different microbial species are included, and their bioactive nature is described.

ПРИГНІЧЕННЯ ФОРМУВАННЯ ШЛУНКОВИХ ВИРАЗОК ПРИ ІМОБІЛІЗАЦІЙНОМУ ВОДОІМЕРСІЙНОМУ СТРЕСІ ПОПЕРЕДНЬОЮ ТРАНСПЛАНТАЦІЄЮ МУЛЬТИПОТЕНТНИХ СТРОМАЛЬНИХ КЛІТИН

To investigate the effect of pre-transplantation of multipotent stromal cells (MSCs) of bone marrow on gastric ulcer formation and the state of the immune system in conditions of acute and prolonged stress. Wistar rats reproduced immobilizing water-immersion stress of 2 types: acute and prolonged. Investigated the number and area of stress ulcers, thymus and spleen, as well as hematologic parameters, proliferative and cytotoxic activity of peripheral blood mononuclear cells, splenocytes and cells of lymph nodes, determined the absorption activity of neutrophils. With prolonged stress as a result of MSC transplantation, the number and area of ulcers significantly decreased, indicating the adaptive protective effect of cells. With acute stress, the introduction of MSC had virtually no effect on ulcer formation. With prolonged stress, there was a decrease in thymus, spleen and leukocyte counts in the blood. Under the influence of transplanted MSCs, the number of all mobilized cells was normalized with the exception of lymphocytes. The natural cytotoxicity and proliferative activity of splenocytes, cells of lymph nodes and peripheral blood in acute and prolonged stress as a result of the introduction of MSC did not change significantly. The introduction of bone marrow MSС 24 h before the last reproduction of stress responses in the model of prolonged stress significantly reduced the number and area of ulcers, which generally indicates the anti-ulcer effect of cells, and normalized the stress-induced quantitative cellular changes in the immune system. Transplantation of bone marrow MSCs to rats prior to reproduction of stress enhances the adaptive antistress mechanisms that develop during prolonged stress, leading to suppression of gastric ulcer formation and significantly altering immune system activity. It can be assumed that one of the mechanisms of action on the body of MSCs is to promote the formation of adaptive responses.

The effects of the transplantation of thymus-derived multipotent stromal cells on the immune system and survival of lethally irradiated mice

The traditional source for regeneration of the immune system is hematopoietic stem cells. Multipotent stromal cells (MSCs), especially MSCs of the thymus, have been significantly less studied for this purpose.The aim was to study the regenerative, immunobiological and radioprotective properties of thymus-derived multipotent stromal cells.Materials and methods. Researches were conducted to study the effect of transplantation of thymus-derived MSCs on the survival and features of restoration of the immune system of lethally irradiated mice. Lethally irradiated (with dose 9 Gy) CBA mice, 5-6 weeks old, were injected intravenously with 5·104 thymus-derived MSCs. On the 30th day the cellularity of lymphoid organs, bone marrow and blood, natural and adaptive immunity were studied.Results. It was found that transplanted thymus-derived MSCs significantly prolonged the survival and average lifespan of mice, restored the cellularity of bone marrow, the ability of bone marrow stromal cells to form fibroblast colonies, greatly increased the cellularity of the thymus and contributed to the normalization of the number of leukocytes in the blood. In addition, the natural cytotoxic activity of splenocytes and their ability to synthesize α/β- and γ-interferons, significantly increased, the number of antibody-producing cells was stimulated and the synthesis of antibodies increased. The concentration of the tumor necrosis factor α in the blood was significantly reduced.Conclusions. The results indicate that thymus-derived MSCs possess pronounced regenerative and immunobiological activity, which provides these cells with radioprotective ability. The obtained data can be used to develop combined cell transplants and new methods for improving their regenerative potential and radioprotective effects.

Immunostimulatory effects of cordycepin-enriched WIB-801CE from Cordyceps militaris in splenocytes and cyclophosphamide-induced immunosuppressed mice.

The medicinal mushroom Cordyceps militaris has been reported to possess anticancer and immunomodulatory effects. We investigated the immunostimulatory effects of culture supernatant of C.militaris (WIB-801CE) by examining its in vitro enhancing effects on cell proliferation and cytokine releases in splenocytes and its in vivo effects on cyclophosphamide-induced immunosuppressed mice. WIB-801CE enhanced normal and methotrexate-induced cell proliferation. WIB-801CE significantly ameliorated interleukin (IL)-2, interferon-γ, and tumor necrosis factor-α secretion in methotrexate-induced splenocytes. Oral administration of WIB-801CE effectively increased the cyclophosphamide-suppressed splenocyte proliferation and natural killer cytotoxic activity. WIB-801CE effectively recovered cyclophosphamide-induced decreases in IL-2, interferon-γ, tumor necrosis factor-α, and IL-10 level. The collective data implicate WIB-801CE as a therapeutic candidate in ameliorating the immunosuppression through immunostimulatory properties.

Effects of recombinant canine interferon-γ injected before general anesthesia with propofol and isoflurane on natural killer cytotoxic activity during anesthesia in dogs

We aimed to determine whether subcutaneous injection of recombinant canine interferon-γ (rCaIFN-γ) 1h before general anesthesia with a combination of propofol and isoflurane (P-I) changes the cytotoxic activity of natural killer (NK) cells during anesthesia in dogs. Nine clinically healthy beagles were assigned to one of two groups: rCaIFN-γ–treated group (n=5) and control group (no treatment, n=4). One hour before P-I anesthesia, rCaIFN-γ was subcutaneously injected at a dose of 1×104U/kg body weight for the test group and physiologic saline was subcutaneously injected for the control group. Blood samples were collected 1h before P-I anesthesia (immediately before rCaIFN-γ injection) and 1 and 3h after anesthesia induction. NK cytotoxic activity was measured using the Rose Bengal assay, using canine thyroid adenocarcinoma cells as target cells. In the control group, NK cytotoxic activity decreased significantly over time (P<0.05). On the other hand, in the rCaIFN-γ group, the activity increased for the first hour after anesthesia induction without a significant difference from the level before anesthesia; furthermore, the activity at 3h after anesthesia induction was comparable with that before anesthesia. NK cytotoxic activity at 1 and 3h after anesthesia induction was significantly higher in the rCaIFNγ group than in the control group (P<0.05). Subcutaneous injection of rCaIFN-γ 1h before P-I general anesthesia not only maintained but also enhanced NK cytotoxic activity up to 3h after anesthesia induction in dogs. In conclusion, subcutaneous injection of rCaIFN-γ before cancer resection in cancer-bearing dogs might be effective for preventing intraoperative dissemination of cancer cells and postoperative cancer recurrence and metastasis.

Extract of metabolic products of Bacillus subtilis AK augments natural killer cell cytotoxic activity

ABSTRACTAimNatural killer (NK) cells play an important role in immune surveillance against viral diseases and cancer. Probiotics, live bacteria beneficial to human health, and some bacterial metabolic products are reported to augment NK cell activity and possibly result in the prevention of tumor development. The aim of this study was to investigate the effect of an extract of metabolic products of Bacillus subtilis AK (EMBSAK), a selected clone of Bacillus subtilis natto, on NK cell activity in human volunteers and mice.MethodsIn the human study, healthy volunteers ingested an EMBSAK‐containing commercially available product, SARABAGAN, for 7 days. In the mice study, BALB/c wild‐type (WT), interferon (IFN)‐γ‐deficient ( IFN‐γ−/−) and RAG 2‐deficient ( RAG −/− ) mice were given oral SARABAGAN 80 mg/kg/day for 7 days. Cytotoxic activity and NK cell number were then examined on 51Cr release assay and flow cytometry, respectively.ResultsOral EMBSAK frequently increased NK cell cytotoxicity, but not NK cell population, in human volunteers in a dose‐dependent manner. Moreover, oral EMBSAK augmented NK cell cytotoxicity, but not NK cell number and population, in WT and RAG 2‐deficient, but not IFN‐γ‐deficient, mice. This suggests that supplemental intake of EMBSAK enhances NK cell cytotoxic activity, but not cell number, depending on IFN‐γ but not on acquired immune cells.ConclusionEMBSAK may be useful to prevent infectious and malignant disease via activation of NK cell cytotoxicity.

Natural Killer Cell Receptors and Cytotoxic Activity in Phosphomannomutase 2 Deficiency (PMM2-CDG).

BackgroundPMM2-CDG is the most common N-glycosylation defect and shows an increased risk of recurrent and/or severe, sometimes fatal, infections in early life. We hypothesized that natural killer (NK) cells, as important mediators of the immune response against microbial pathogens and regulators of adaptive immunity, might be affected in this genetic disorder.ObjectiveTo evaluate possible defects on PMM2-CDG NK peripheral blood cell number, killing activity and expression of membrane receptors.MethodsWe studied fresh and activated NK cells from twelve PMM2-CDG cells. The number and expression of lymphoid surface receptors were studied by flow cytometry. The NK responsiveness (frequency of degranulated NK cells) and killing activity against K562 target cells was determined in the NK cytotoxicity assay.ResultsWe found an increase of blood NK cells in three patients with a severe phenotype. Two of them, who had suffered from moderate/severe viral infections during their first year of life, also had reduced T lymphocyte numbers. Patient activated NK cells showed increased expression of CD54 adhesion molecule and NKG2D and NKp46 activating receptors. NKp46 and 2B4 expression was inversely correlated with the expression of NKG2D in activated PMM2-CDG cells. Maximal NK activity against K562 target cells was similar in control and PMM2-CDG cells. Interestingly, the NK cell responsiveness was higher in patient cells. NKG2D and specially CD54 increased surface expression significantly correlated with the increased NK cell cytolytic activity according to the modulation of the killer activity by expression of triggering receptors and adhesion molecules.ConclusionsOur results indicate that hypoglycosylation in PMM2-CDG altered NK cell reactivity against target cells and the expression of CD54 and NKG2D, NKp46 and 2B4 activating receptors during NK cell activation. This suggests a defective control of NK cell killing activity and the overall anti-viral immune response in PMM2-CDG patients. The present work improves our understanding of the immunological functions in PMM2-CDG and possibly in other CDG-I types.

Association between IL18-607C/A and -137G/C polymorphisms and susceptibility to non-small cell lung cancer in a Chinese population

Lung cancer is one of the main causes of cancer-related mortality in males and females worldwide. A pleiotropic effect has been observed in the interleukin 18 gene (IL18); its effects include the activation of natural killer cell cytotoxicity and the promotion of the Th1 immune response through the alteration of the expression of interferon-γ and TNF-α in humans. IL18 is therefore involved in the elimination of tumor cells in the human body. We recruited 357 patients with non-small cell lung cancer (NSCLC) and 414 controls to evaluate the correlation between two genetic variations (IL18-607C/A and IL18-137G/C) and the pathogenesis of NSCLC. We used polymerase chain reaction-restriction fragment length polymorphism to genotype IL18-607C/A and IL18-137G/C. Statistical analysis revealed that individuals harboring the AA genotype of IL18-607C/A had an increased risk of NSCLC compared to those harboring the CC genotype (OR = 2.20, 95%CI = 1.30-3.74). Individuals expressing the A allele of IL18-607C/A had an elevated risk of developing NSCLC compared to those expressing the C allele (OR = 1.31, 95%CI = 1.06-1.62). In summary, our analysis shows that the IL18-607C/A genetic variation is related to the risk of NSCLC, whereas the IL18-137G/C variation is not. Therefore, the IL18-607C/A variation is related to the pathogenesis of NSCLC in the Chinese population studied.

Immunomodulatory and cellular antioxidant activities of pure compounds from Teucrium ramosissimum Desf.

Evaluation of the immunomodulatory activity of plant compounds is an interesting and growing area of research. Teucrium ramosissimum Desf. is a native and endemic medicinal plant from the South of Tunisia traditionally used for the treatment of many diseases. The anti-inflammatory activity of apigenin-7-glucoside, genkwanin, and naringenin isolated from T. ramosissimum were assayed. The phagocytic activities of macrophage and lymphocyte proliferation were investigated in the absence and presence of mitogens (lipopolysaccharide [LPS] or lectin). Depending on the concentrations, the compounds affect macrophage functions by modulating their lysosomal enzyme activity and nitric oxide (NO) release. The tested compounds enhance significantly splenocyte proliferation, either with or without mitogen stimulation. In studies to assess any potential effects of apigenin-7-glucoside, genkwanin, and naringenin on innate immunity, the results showed that these compounds significantly enhanced the killing activity of natural killer (NK) cells and cytotoxic activity of the T lymphocyte (CTL) isolated from splenocytes. These results suggest that T. ramosissimum compounds such as apigenin-7-glucoside, genkwanin, and naringenin may be potentially useful for modulating immune cell functions in physiological and pathological conditions.

Characteristics of the Immune System and the Risk of Developing Endogenous Psychosis at Juvenile Age

Study aim. To investigate immunological parameters at the early stages of development of juvenile schizophrenia. Materials and methods. Immunological profiles were determined in patients aged 16–25 years receiving in-patient treatment. Patients were divided into two groups. Group 1 consisted of 39 patients with psychopathological symptomatology at the non-psychotic level (prodrome group) and group 2 consisted of 38 patients with first onset of endogenous psychosis (psychosis group). Immunological parameters included phagocytic activity, lymphocyte natural killer cytotoxic activity, production of interleukins IL-1, IL-4, IL-10, and interferon γ, and circulating immune complex (CIC) levels. These investigations were performed before and after treatment. Results. The experiments reported here showed that changes in immune system function were seen in patients at the earliest stages of disease development, with activation of proinflammatory and anti-inflammatory interleukins, decreases in phagocytic index and natural killer lymphocyte cytotoxic activity, and phagocytic number. Development of psychosis was associated with persistence of the high level of IL-10 production, the decreased level of natural killer cytotoxic activity, and the decreased phagocytic index, with accumulation of CIC. Conclusions. The authors recommend the use of not only psychotropic, but also immunomodulatory agents at the early stage of the development of endogenous psychosis.

In vitro and in vivo anti-inflammatory activity of digested peptides derived from salmon myofibrillar protein conjugated with a small quantity of alginate oligosaccharide.

Salmon myofibrillar protein (Mf) was investigated as a source of edible anti-inflammatory products. Peptides produced by stepwise digestion of Mf (without carbohydrate) with pepsin and trypsin had little effect on the secretion of inflammation-related compounds from lipopolysaccharide-stimulated RAW 264.7 macrophage cells. However, peptides prepared from Mf conjugated with alginate oligosaccharide (AO; 19 μg/mg protein) (dMSA) through the Maillard reaction in the presence of sorbitol significantly reduced the secretion of the pro-inflammatory mediators nitric oxide, tumor necrosis factor (TNF)-α and interleukin (IL)-6, as well as mRNA expression of TNF-α, IL-6, inducible nitric oxide synthase and cyclooxygenase-2. Additionally, dMSA inhibited acute inflammation in a carrageenan-induced model of paw edema in mice, but had no effect on natural killer cell cytotoxic activity or macrophage phagocytosis. These results suggest that fish Mf conjugated with AO may be a potential food material with anti-inflammatory function.