This study sought to shed light on the killing effect of peripheral blood mononuclear cells (PBMCs) irradiated by gamma ray at a dose of 1 Gy on cultured human gastric tumor cell line MKN-28. The radiation dose rate of 17 Gy/min was used. The groups in the experiment were MKN-28 cell control group, PBMCs control group, MKN-28 tumor cells with irradiated or non-irradiated PBMCs co-cultured groups. Radiation dosage was one Gray, acridine orange/ethidium bromide (AO/EB) staining was used for observation of the killing effects of PBMCs on tumor cells in different period. Cells were harvested 240 h later and observed by transmission electron microscopy. The result showed the living period of irradiated PBMCs was shorter than that of non-irradiated PBMCs. In the irradiated and non-irradiated groups,a few PBMCs were still alive after being cultured for 240 h, but the cell volume was larger than that of lymphocytes. These cells were identified as monocytes (95%) or DCs (5%) by transmission electron microscopy. The co-culture of irradiated PBMCs and MKN-28 cells showed that tumor cells were eliminated after 96 h. As compared with the non-irradiated goup, the irradiated PBMCs had more potent ability for killing tumor. The results demonstrate that 1 Gy gamma irridiation can improve the killing effect of PBMCs on the tumor cells, and that 1 Gy gamma irritation can also induce shorter living period of lymphocytes in PBMCs cultured in vitro, but such irritation has little effect on the living period of monocytes and DCs in PBMCs.
Cell Survival ; Coculture Techniques ; Gamma Rays ; Humans ; Leukocytes, Mononuclear ; cytology ; immunology ; radiation effects ; Stomach Neoplasms ; immunology ; pathology ; Tumor Cells, Cultured

OBJECTIVETo investigate the effects of extremely low frequency magnetic and electric fields (ELFEMFs) emitted from 380 kV transmission lines on some leukocyte differentiation antigens in dairy cows.

METHODSThe study was carried out in 5 cows exposed to 1.98-3.28 microT of ELFEMFs and in 5 control cows exposed to 0.2-0.7 microT of ELFEMFs. Following haematological and immunologic parameters were measured in both groups: WBC, CD45R, CD6, CD4, CD8, CD21, and CD11B leukocyte antigen expression.

RESULTSSome of the haematological and immunologic parameters under investigation were similar in both groups. However, CD8 (T lymphocyte surface antigen) was higher in the exposed group (1.35 +/- 0.120 vs. 0.50 +/- 0.14 x 10(3)/mL). Furthermore, the CD4/CD8 ratio (0.84 +/- 0.05 and 2.19 +/- 0.16 for exposed and not exposed cows respectively) and circadian rhythm were different between the two groups.

CONCLUSIONExposure to ELFEMFs is responsible of the abnormal temporal variations and distribution of some haematological and immunological parameters in dairy cows.

Animals ; Antigens, CD ; blood ; Cattle ; Circadian Rhythm ; radiation effects ; Electromagnetic Fields ; Environmental Exposure ; analysis ; Female ; Leukocytes ; immunology

Constructing a bone marrow chimera prior to graft transplantation can induce donor-specific immune tolerance. Mixed chimerism containing hematopoietic cells of both recipient- and donor-origin has advantages attributed from low dose of total body irradiation. In this study, we explored the mechanism of mixed chimerism supplemented with depletion of Natural Killer cells. Mixed chimerism with C57BL/6 bone marrow cells was induced in recipient BALB/c mice which were given 450 cGy of gamma-ray irradiation (n = 16). As revealed by reduced proliferation and cytokine production in mixed leukocyte reaction and ELISpot assay (24.6 vs 265.5), the allo-immune response to bone marrow donor was reduced. Furthermore, the induction of transferable immunological tolerance was confirmed by adoptive transfer and subsequent acceptance of C57BL/6 skin graft (n = 4). CD4+FoxP3+ regulatory T cells were increased in the recipient compartment of the mixed chimera (19.2% --> 33.8%). This suggests that regulatory T cells may be therapeutically used for the induction of graft-specific tolerance by mixed chimerism.
Animals ; Bone Marrow Cells/cytology ; *Bone Marrow Transplantation ; Cell Proliferation ; Chimerism ; Cytokines/metabolism ; Gamma Rays ; Graft Survival ; *Immune Tolerance ; Killer Cells, Natural/immunology/radiation effects ; Leukocytes/immunology/radiation effects ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Models, Animal ; Skin Transplantation ; T-Lymphocytes, Regulatory/cytology/*immunology/metabolism ; Whole-Body Irradiation

BACKGROUNDPrevious studies showed that anti MHC-II monoclone antibody (MAb) only had partial inhibiting effect of alloreactive mixed lymphocyte reaction (MLR) in vitro and it was unsteady and non-persistent. The aim of this research was to determine whether radioactive isotope (188)Re marked MHC-II antibody could benefit the allograft acceptance in transplantation as compared to normal MHC-II antibody.

METHODS188Re was incorporated to 2E9/13F (ab')(2) which is against swine MHC class II antigen (MAb-(188)Re). Porcine peripheral blood mononuclear (PBMC) cells were examined for proliferation and cytokine mRNA expression after stimulation with MHC-II MAb or MAb-(188)Re.

RESULTSThe proliferative response of recipient PBMCs in mixed lymphocyte reaction (MLR) to donor alloantigen showed that the stimulation index of MAb-(188)Re group was significantly lower than the MHC-II MAb group and control (P < 0.05). mRNA expression of interleukin 2, interferon Υ and tumor necrosis factor α (type 1 cytokines) was lower in MAb-(188)Re group than the MHC-II MAb group, while interleukin 10 (type 2 cytokines) was higher in MAb-(188)Re group in the first 24 hours.

CONCLUSIONMAb-(188)Re could help the graft acceptance by inhibiting T cell proliferation, lowering the expression of type 1 cytokines and elevating the type 2 cytokines produced by PBMC.

Animals ; Antibodies, Monoclonal ; chemistry ; pharmacology ; Cell Proliferation ; drug effects ; Interleukin-10 ; genetics ; Interleukin-2 ; genetics ; Isoantigens ; immunology ; Leukocytes, Mononuclear ; drug effects ; radiation effects ; Lymphocyte Culture Test, Mixed ; Mitomycin ; pharmacology ; Radioisotopes ; Reverse Transcriptase Polymerase Chain Reaction ; Rhenium ; Swine ; Tumor Necrosis Factor-alpha ; genetics