Dynamika replikacji wirusa BLV i PI3 w hodowli komorek FLK

The influence of non-cytopathic and cytopathic strains of M-PI₃ parainfluenza virus on bovine leukaemia virus (BLV) replication was assessed. It was found that enzymatic activity of BLV revertase from FLK cells was 21 471 cpm, 23 127 cpm, 12 406 cpm and 2506 cpm after 24, 48, 72 and 96 hours, respectively. In FLK cells infected additionally with the cytopathic strain M-PI₃ the number of cpm was lower than in that of control cells (FLK uninfected with M-PI₃) and was 16 367, 17 329, 20 987 and 4637 after 24, 48, 72 and 96 hours, respectively. The highest activity of BLV revertase from FLK cells infected also with the non-cytopathic strain of M-PI₃ was obtained after 24 and 48 h; the findings were: 26 451 cpm and 28 319 cpm, respectively. This activity after 72 h was 18 952 cpm and after 96 h 3421 cpm. The yield of BLV from FLK cells infected additionally with the non-cytopathic strain M-PI₃ was higher by 37,9 per cent after 24 h p.i. and by 38,8 per cent after 48 h p.i. than in that received from FLK control cels. The results have indicated the synergetic activity of BLV and non-cytopathic M-PI₃ viruses cultivated in FLK cells.