抄録
The relationship between the number of circulating leukocytes and amount ofvirus-inhibiting factor (IF) or interferon appearing in blood stream in response toinjection of E. coli endotoxin or Newcastle disease virus (NDV) was studied in miceafter whole-body X-irradiation. Two days after irradiation with 500R, the leukocytecount fell to 7% of the normal value. Production of IF, however, was not depressedwhen induced with endotoxin 2 days after irradiation, while NDV induced a slightlylower titer of IF, 1/1.6 of that in non-irradiated mice. When induced 5 days afterirradiation, though leukocyte count remained at 8 to 9% of the normal value, IF titersattained were only 1/3 and 1/4 of the control value with endotoxin and NDV, respectively.In mice given 1000 R before 2 days, leukocyte number was less than 1% of thenormal value, while IF titers reached 1/2.7 and 1/5 of that in the control mice withendotoxin and NDV, respectively. The lack of parallel between the leukocyte count andamount of IF produced suggest that circulating leukocytes do not produce IF.
