TY - JOUR
T1 - Anti-prion activity of protein-bound polysaccharide K in prion-infected cells and animals
AU - Hamanaka, Taichi
AU - Sakasegawa, Yuji
AU - Ohmoto, Akihiro
AU - Kimura, Tomohiro
AU - Ando, Takao
AU - Doh-ura, Katsumi
N1 - Funding Information:
We thank Keiko Nishizawa and Ayumi Oguma from Tohoku University for their technical assistance. This study was supported by the Health and Labor Sciences Research Grants (Research on Measures for Intractable Diseases) from the Ministry of Health, Labor, and Welfare of Japan, and by the Program for the Promotion of Fundamental Studies in Health Science of the NIBIO in Japan.
PY - 2011/2/11
Y1 - 2011/2/11
N2 - Protein-bound polysaccharide K (PSK) is a clinical immunotherapeutic agent that exhibits various biological activities, including anti-tumor and anti-microbial effects. In the present study, we report on the anti-prion activity of PSK. It inhibited the formation of protease-resistant abnormal prion protein in prion-infected cells without any apparent alterations in either the normal prion protein turnover or the autophagic function in the cells. Its anti-prion activity was predominantly composed of the high molecular weight component(s) of the protein portion of PSK. A single subcutaneous dose of PSK slightly but significantly prolonged the survival time of peritoneally prion-infected mice, but PSK-treated mice produced neutralizing antibodies against the anti-prion activity of PSK. These findings suggest that PSK is a new anti-prion substance that may be useful in elucidating the mechanism of prion replication, although the structure of the anti-prion component(s) of PSK requires further evaluation.
AB - Protein-bound polysaccharide K (PSK) is a clinical immunotherapeutic agent that exhibits various biological activities, including anti-tumor and anti-microbial effects. In the present study, we report on the anti-prion activity of PSK. It inhibited the formation of protease-resistant abnormal prion protein in prion-infected cells without any apparent alterations in either the normal prion protein turnover or the autophagic function in the cells. Its anti-prion activity was predominantly composed of the high molecular weight component(s) of the protein portion of PSK. A single subcutaneous dose of PSK slightly but significantly prolonged the survival time of peritoneally prion-infected mice, but PSK-treated mice produced neutralizing antibodies against the anti-prion activity of PSK. These findings suggest that PSK is a new anti-prion substance that may be useful in elucidating the mechanism of prion replication, although the structure of the anti-prion component(s) of PSK requires further evaluation.
KW - Immunotherapeutic agent
KW - Prion
KW - Prion-infected cells
KW - Protein-bound polysaccharide K
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U2 - 10.1016/j.bbrc.2011.01.030
DO - 10.1016/j.bbrc.2011.01.030
M3 - Article
C2 - 21219866
AN - SCOPUS:79651470773
VL - 405
SP - 285
EP - 290
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
SN - 0006-291X
IS - 2
ER -