Masayoshi Aosasa

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We screened six mouse monoclonal antibodies (mAbs) against prion protein (PrP), which were previously established in our laboratory, for inhibitory activity against PrP(Sc)-accumulation in scrapie-infected cell lines and identified two mAbs, 3S9 and 2H9, as possessing this inhibitory activity. mAb 3S9 recognized an epitope including 154th tyrosine in the(More)
Mouse embryonic stem (ES) cells can be maintained in an undifferentiated state in the presence of leukemia inhibitory factor (LIF), a member of the interleukin-6 cytokine family. In other mammals, this is not possible with LIF alone. Chicken ES-like cells (blastodermal cells) have only been cultured with mouse LIF because chicken LIF was not available.(More)
We generated two recombinant chicken IgYs, designated Ab3-15 and Ab4-19, against mammalian prion protein (PrP) from the single chain fragment of variable region (scFv) antibodies. These two antibodies recognized PrP(Sc) from bovine spongiform encephalopathy (BSE) in cattle and were more sensitive than the corresponding scFv antibodies. These antibodies also(More)
Interleukin-6 (IL-6), a multipotential cytokine that plays roles in regulating immune responses, acute phase reactions and hematopoiesis, induces proliferation and antibody production in hybridoma cells. The biological activities of the recombinant chicken IL-6 (rchIL-6) were determined using murine and chicken hybridoma cells. Cell proliferation and(More)
A panel of chicken monoclonal antibodies (mAbs) was developed against prion protein (PrP), the sequence of which is a highly conserved molecule among mammals. A portion of the splenocytes from chickens immunized with recombinant mouse PrP was fused with the chicken B cell line, MuH1. The remaining splenocytes were used to generate the recombinant mAbs by(More)
A monoclonal antibody (MAb) specific for chicken interleukin-6 (chIL-6) was generated by using Balb/c mice immunized with recombinant chIL-6 (rchIL-6). On Western blot analysis, the MAb, designated E3, reacted with rchIL-6 but not with recombinant murine IL-6 (rmIL-6). The MAb E3 also reacted with supernatant of the chicken macrophage-like cell line HD11(More)
Background. N-Acetylneuraminic acid and N-glycolylneuraminic acid (NeuGc) are the most common sialic acids in mammals, and NeuGc has attracted attention as a tumor-associated antigen. Methods. In frozen liver sections from patients with hepatocellular carcinoma, glycolipid-type NeuGc was detected on the surface of liver cancer cells in 9 of 17 samples(More)
Mucin-type O-glycosylation is initiated by a large number of UDP-GalNAc: polypeptide N-acetylgalactosaminyltransferases (GalNAc-T). Although extensive in vitro studies using synthetic peptides as substrates suggest that most GalNAc-Ts exhibit overlapping substrate specificities, many studies have shown that individual GalNAc-Ts play an important role in(More)
When compared with mammalian IgG, chicken IgY is advantageous in terms of cross-reactivity. In this study, two plasmids were constructed for expression of recombinant chicken IgY derived from a chicken hybridoma. The first was for expression of the light (L) chain, and the other was for the heavy (H) chain with a histidine (His) tag at the carboxy-terminal.(More)
Antibodies can distinguish not only differences in amino acid sequences (primary structure), but also differences in three-dimensional structure and thus may be useful for detecting the conversion of prion proteins, especially in vivo. For diagnosis, we prepared chicken single chain variable fragment (scFv) antibodies that specifically recognized a prion(More)