The Tween-ether treated hemagglutinin of parainfluenza 2 virus

Summary

Several properties of the Tween-ether treated hemagglutinin of parainfluenza 2 virus have been, studied and compared with those of the untreated virus. When the untreated preparation contains a large proportion of infective or “complete” particles, Tween-ether treatment results in a 64- to 128-fold enhancement of the hemagglutinin titer. With less “complete” particles, the enhancement is only 16- to 32-fold. By ultrafiltration it is shown that Tween-ether treated hemagglutinin consists of particles much smaller than untreated virus particles, including some which pass through 10 mμ pores. This hemagglutinin can be stored at 4°C for long periods without loss of titer. At 37°C, 41°C, 56°C and −70°C it is less stable than untreated virus. It was found to be efficient in eliciting antibodies in rabbits but more sensitive in detecting hemagglutination inhibition antibodies in human sera.