Abstract
On the nature of vaccine hemagglutinin (to be referred to as VH) many works have been carried out to characterize it more precisely. These may be itemized as follows: 1) VH is a soluble substance separable from the elementary body by certain procedures, 2.) VH is considered to be destroyed by cobra venom or Cl. welchii alpha-toxin, and 3) the possibility is indicated that two hemagglutinins, thermolabile and thermostable, exist and these are quite different from the L-S antigen. The present authors reported that VH was readily inactivated by some nitrogen mustards. The effect of ultraviolet irradiation on VH has been examined, because the biological effect of the nitrogen mustards is considered to be analogous in some point to that of ultraviolet or X-ray irradiation, and the folling report deals with the results obtained.
