Abstract
1. Skin lesions characteristic to herpes simplex appeared 5-6 days after subcutaneous inoculation of virulent strian of herpes simplex virus (HSV) into the mid flank of CFI mice. Multiplication of HSV at the inoculated site was proved by virus titration and fluorescent antibody technique.
The cutaneous findings are confined to the mid flank, which shows bandlike crustings with superficial dry adherent scales. Histological examination revealed intraepidelmal vesicles and ballooning degnration but no intranuclear inclusion bodies.
2. Repeatied intraperitoneal injection of avirulent strain of HSV made the mice immune and prevented the development of the lesion perfectly but neonatally thymectomized mice developed the lesion even after immunization.
3. Thymectomized mice and unoperated mice produced neutralizing serum antibody against HSV almost to the same extent 7 days after the immunization.
4. From the results described above, it is thought that the depression of the capacity to develop aquired resistance against HSV in neonatal thymectomized mice is due not to circulating neutraliging antibody but rather to cellular type of immunity.
