抄録
We studied the inhibitor gradient for Mumps-NDV-Influenza group by heat-stable mucoprotein-like substance (M-substance) from ox-bile. The M-substance is a sort of competitive inhibitor which is digested by various receptor destroying enzymes.
The inhibitory titer of this substance for hemagglutination of untreated MIN group viruses is highest for mumps virus (Enders strain), and lowest for NDV and when these viruses are heated at 52°, 30′, its inhibitory activity is increased for influenza virus, but not for Enders strain and NDV. When the viruses inactivated by ultraviolet irradiation, formalin or merthiolate, are used, the hemagglatination inhibitory titer of this substance is the same titer as the when the active viruses are used. By such treatments the viruses can not be indicator viruses.
These treated viruses have the same biological properties as active viruses, except that the infectivity are lost. After digestion of M substance by influenza viruses, NDV and mumps virus, the inhibitory activity of this substance against heated PR 8, is completely removed except that by mumps virus. In the same way, the inhibitory activity against untreated or heaten mumps do not be removed.
It is doubtful that mumps virus has the enzymic action for the M substance. It is suggested from these results that M substance is useful as an accessory method in differentiation of MNI group, but it will be necessary to do further investigations for the method mentioned to be applied to the practical purposes.
