Abstract
The course of influenza infection in mice with mouseadapted PR8 strain of influenza A virus was studied by means of immunofluorescent staining. Absolute 104.1 EID50 amount of virus corresponding to 60 LD50 was inhaled as aerosol into each mouse weighing 10g in average.
Obtained results can be summarized as follows:
1) Synthesis of virus antigens was restricted to the cells lining along bronchoalveolar tree, although the growth of virus in alveolar cells started some 12 hours behind that in bronchial cells.
2) In the late stage of infection, specific immunofluorescence was still detectable with alveolar cells. Whereas, new antigen synthesis was not detectable in newly built metaplastic cells along main bronchus.
3) Infiltration of rounded cells, probably lymphocytes and monocytes in origin, which plays dominant role to explain the histological characteristics of influenza pneumonia as interstitium pneumonitis, was found as in many other works. However, no specific fluorescence was detectable among the population of these rounded cells, this suggesting that these cell infiltrations are the reflection of the non-specific inflammation.
