Frequency of chromosome disorders occurring in human lymphocytes in the in vitro exposure to different doses of deuterons as protected by adeturon

Peripheral blood of 4 healthy donors was exposed to deutrons with the energy 4,2 GeV/nuclone and the intensivity of 4 to 6.10(10) particles per impulse, the capacity of the dose being 0,008 Gr/sec. The LPE of deutrons was 2,14 MeV sm2/g. Irradiation doses were 0,26; 0,49; 0,97; 2,02; 3,80 Gr. 15-20 min prior to irradiation, the protector adeturone was added at a concentration of 550 micrograms/ml of blood. Chromosome aberrations were analyzed in protected and unprotected blood samples. The results were treated using the method of variance and regression analysis. The correlative correspondence between the number of chromosome aberrations and an approximate dose of actual irradiation was established as Y = 0,13 d + 6,55.10(-4) D2 for dicentrics and as 0,26 D + 12,6.10(-4) D2 + 4,5 for the total percentage of aberrations. The pattern of the dose - effect dependence was retained in protected samples. The calculated values of the factor of dose decrease confirmed antiirradiation properties of adeturone.     

N-glycosylation of recombinant human interferon-gamma produced in different animal expression systems

Recombinant human interferon-gamma (IFN-gamma) was expressed in Chinese hamster ovary cells, baculovirus-infected Sf9 insect cells and the mammary gland of transgenic mice. The N-linked carbohydrate populations associated with both Asn25 and Asn97 glycosylation sites were characterized by matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) in combination with exoglycosidase array sequencing. A site-specific analysis of dual (2N) and single (1N) site-occupancy variants of IFN-gamma derived from Chinese hamster ovary cells showed that N-glycans were predominantly of the complex bi- and triantennary type. Although Asn25-linked glycans were substituted with a core fucose residue, Asn97 N-glycans were predominantly non-fucosylated, and truncated complex and high-mannose oligosaccharide chains were also evident. Transgenic mouse derived IFN-gamma exhibited considerable site-specific variation in N-glycan structures. Asn25-linked carbohydrates were of the complex, core fucosylated type, Asn97-linked carbohydrates were mainly of the oligomannose type, with smaller proportions of hybrid and complex N-glycans. Carbohydrates associated with both glycosylation sites of IFN-gamma from Sf9 insect cells were mainly tri-mannosyl core structures, with fucosylation confined to the Asn25 site. These data demonstrate the profound influence of host cell type and protein structure on the N-glycosylation of recombinant proteins.