Oral Administration of Silk Peptide Enhances the Maturation and Cytolytic Activity of Natural Killer Cells

Silk peptide, the hydrolysate of silk protein derived from cocoons, has been employed as a biomedical material and is believed to be safe for human use. Silk peptide display various bioactivities, including anti-inflammatory, immune-regulatory, anti-tumor, anti-viral, and anti-bacterial. Although earlier investigations demonstrated that silk peptide stimulates macrophages and the production of pro-inflammatory cytokines, its effect on natural killer (NK) cell function has not yet been explored. In this study, we initially confirmed that silk peptide enhances NK cell activity in vitro and ex vivo. To assess the modulatory activity of silk peptide on NK cells, mice were fed various amounts of a silk peptide-supplemented diet for 2 months and the effects on immune stimulation, including NK cell activation, were evaluated. Oral administration of silk peptide significantly enhanced the proliferation of mitogen- or IL-2-stimulated splenocytes. In addition, oral silk peptide treatment enhanced the frequency and degree of maturation of NK cells in splenocytes. The same treatment also significantly enhanced the target cell cytolytic activity of NK cells, which was determined by cell surface CD107a expression and intracellular interferon-γ expression. Finally, oral administration of silk peptide stimulated T helper 1-type cytokine expression from splenic lymphocytes. Collectively, our results suggest that silk peptide potentiates NK cell activity in vivo and could be used as a compound for immune-modulating anti-tumor treatment.

Effects of Panax ginseng Aqua - acupuncture on Lymphocyte Activities in Glucocorticoid Treated Mice / 대한면역학회지

Panax ginseng (PG) has been used as an important analeptic in traditional medicine. This study was purposed to investigate the effect of PG on immune responses induced by glucocorticoid in mice. PG solution was injected into CV6 and BL23, which are the classical acupuncture points, for 7 days after injection with glucocorticoid. And then B and T cell proliferation and cytolytic activity of natural killer (NK) cells were measured. B cell proliferation by 'H-thymidine incorporation was decreased by about 25% in control group as compared with normal group. However, B cell proliferation was significantly increased 1.8-fold in CV6 group and 2.5-fold in BL23 group as compared with normal group. T cell proliferation by H- thymidine incorporation was decreased by about 15% in control group as compared with normal group. On the other hand, T cell proliferation was significantly increased 1.9-fold in CV6 group and 2.3-fold in BL23 group as cornpared with normal group. Furthermore in purified T cell, the proliferation was furtherly increased rather than in non-purified T cell. The activity of NK cell was remarkably decreased in control group as compared with normal group. However, the activities of NK cells in CV6 and BL23 groups were recovered to the above levels of normal group. On the other hand, the activity of NK cell in the blank locus group was slightly increased compared with control group. However this increasement was not reached the levels of CV6 and BL23 groups. And in the case of purified NK cell, the cytolytic activity of NK cell was respectively increased 1.6-fold in normal group, 1.4-fold in control group, 2.0-fold in blank locus group and 2.0-fold in CV6 group and 1.4-fold in BL23 group as compared to the non-purifed NK cell. These results suggest that PG aqua-acupuncture at CV6 and BL23 may proliferate B and T cells that is suppressed by glucocorticoid, and activate NK cell activity.

In Vitro Antitumor Activities and phenotype Analysis of Tumor—infiltrating Lymphocytes(TIL)and Lymphokine—activating Killer(LAK)Cells From Patients With Osteosarcoma / 中国免疫学杂志

TIL were isolated from the resected tumor mass,and lymphocytes were separated from pe-ripheral blood of 12 patients with osteosarcoma.In vitro antitumor activity and spesificity of rIL—2 activated TIL and LAK cells were determined by 4 hour ~(51)Cr releasing assay.Phenotypeanalysis of TIL were carried out in different intervals of incubation.The results revealed thatduring the incubation period from Day 15—Day 20,the difference between average cytolytic ac-tivities of TIL and LAK ceils with K562 and LiBr cells as target cells(E:T ratio 25:1)were in-significant,while that from 7 of those patients with autotumor cells as target cells were signifi-cant.The phenotype analysis showed that the percentage of CD3~+ cells remained constant,whilethat of CD4~+ cells tends to increase,and that of CD8~+cells tends to decrease during the whole in-cubation period.

Effect of perforin-mediated cytotoxicity on systemic defense mechanisms against primary influenza virus infection / 中国免疫学杂志

Objective:To investigate the effect of perforin-mediated cytotoxicity in primary influenza virus infection.Methods:Perforin-deficient and wild-type C57BL/6 mice were infected intranasally with influenza virus A/PR/8/34. Pulmonary viral growth was determined at various days after infection by pfu experiment. Perforin-mediated apoptotic degeneration was observed by Immunohistochemical staining. LDH-release method was used for detection of specific CTL and NK cell activity from spleen cells.Results:Mice deficient in the perforin gene showed an increased virus growth and prolonged virus shedding. The appearance of apoptotic degeneration in virally infected lung cells was delayed in perforin-deficient mice. The cytolytic activities of natural killer cells and virus-specific cytotoxic T lymphocytes were significantly lower than that of wild-type mice.Conclusion:Perforin plays a critical role in the host defense system against primary influenza virus infection.