Table 1.

Abilities of various Fab fragments to activate YU2 envelope glycoproteinsa

Fab fragmentsCAT activity (% conversion)
HXBc2YU2
−Fab+Fab−Fab+Fab
DO142-104371328
b123911427
DO8i4211250
MTW61DNDND1388
DA4860101682
  • a Recombinant viruses bearing the HXBc2 or YU2 envelope glycoproteins were produced in COS-1 cells. Virions were incubated alone (−) or with (+) Fab fragments directed against the V3 loop (DO142-10) and CD4BS (b12, DO8i, MTW61D, and DA48) at a concentration of 10 μg/ml. CAT activity was measured 72 h after the addition of Molt 4 clone 8 target cells. The values expressed are the precentage conversion of chloramphenicol to acetylated forms.