Chugai Seiyaku Kabushiki Kaisha

Yasuo Sekimori

Tomoyuki Igawa

Masayuki Tsuchiya

Hiroyuki Tsunoda

Reiko Irie

Minoru Machida

Teruo Nakamura

Hajime Miyamoto

Shigeyuki Iijima

Izumi Sugo

Kiyoshi Habu

Hiromitsu Kawata

Akira Hayasaka

Kenju Ueno

The present inventors discovered that stable and highly concentrated IgM solutions can be prepared by using, as an additive, a compound comprising a polyvalent cationic ion, such as magnesium chloride or arginine hydrochloride, to suppress IgM aggregation in solutions.

Highly concentrated stabilized IgM solution

IgM can be obtained in the form of a pentamer by placing the genes encoding the H, L, and J chains on the same vector to transform appropriate host cells. The gene encoding the J chain may be introduced by co-transfection. When no J chain is expressed, the IgM is produced as a hexamer. The transformants obtained according to the present invention achieve a high yield of IgM. The present invention also provides methods which enable separation and quantification of polymeric IgM.

Anti-ganglioside antibodies and compositions

The present invention provides a polyethylene glycol-conjugated erythropoietin (PEG-conjugated EPO) prepared by PEG conjugation on the lysine residue at position 52 of native erythropoietin (native EPO). In order to achieve more sustained efficacy without losing physiological activities of native EPO, a glycoprotein rich in sugar chains, there has been a need to develop a PEG-conjugated EPO with significantly sustained efficacy by introducing a controlled number of PEG molecules at controlled positions. This PEG-conjugated EPO addresses such a need and provides more sustained efficacy.

PEG-conjugated erythropoietin

The present invention provides a gene encoding a fucose transporter, a fucose transporter polypeptide, a method for screening for a compound that binds to a fucose transporter or a compound that inhibits fucose transport activity, a cell having inhibited fucose transporter functions, and a cell wherein the expression of the fucose transporter is inhibited. The present invention further relates to a method for producing recombinant protein, and specifically, to a method for producing protein by which fucose existing within the Golgi apparatus of a host cell is decreased, a method for inhibiting the addition of fucose to protein by which fucose existing within the Golgi apparatus of a host cell is decreased upon production of recombinant protein using the host cell, a method for increasing the cytotoxic activity of an antibody by which an antibody is produced using a cell wherein fucose existing within the Golgi apparatus is decreased, and a cell having a Golgi apparatus wherein fucose existing within the Golgi apparatus is decreased.

Fucose transporter

The present inventors examined use of citric acid buffers for suppressing cryoprecipitation of IgM at a pH range and salt concentration suitable for storing IgM. As a result, the present inventors discovered that citric acid buffers significantly suppress cryoprecipitation.

Methods for stabilizing protein solutions

Polynucleotides encoding anti-ganglioside antibodies

Growing community of inventors

Shizuoka, Japan

Yasuo Sekimori