Influenza Virus Multiplication in Homologously Transplanted Mouse Fetal Tissues

Abstract

Summary The susceptibility of embryonic mouse tissues to infection with various strains of human influenza virus has been tested by transplantation of virus-treated tissues to the subcutaneous space of homologous adult hosts. The technique is relatively simple and gives readily reproducible results. When infection with the virus occurred it was localized to the transplanted donor tissue and the draining axillary and inguinal lymph nodes of the recipient host. No characteristic cytologic changes due to virus proliferation were noted. The capacity of different strains of influenza virus to multiply in transplanted fetal mouse lung varied with the degree of infectivity of the individual strain for adult mouse lung. The purely egg-adapted A′ strain, A/England/1/51, showed no increase in virus titer in the 1st fetal lung generation but acquired proliferative capacity after a single fetal or adult lung passage. Non-neurotropic strains of influenza virus did not multiply in fetal tissues other than lung. An encephalitogenic variant of the WS strain of influenza A (NWS) was infective for mouse fetal lung, intestine, kidney, heart, bladder and spleen but not for skin.