FIG. 1.

The in vitro effect of control and heat-treated (complement-depleted) rodent plasma on virus vector infectivity of cells. Plasma was prepared from immunocompetent (A) and athymic (B) rats as described in Materials and Methods and either exposed to a temperature of 56°C for 30 min or not before incubation with an adenovirus, retrovirus, or HSV vector expressing the lacZ cDNA for 1.5 h. The viruses were then added onto Vero cells and, 16 h later, the number of lacZ cDNA-expressing cells was recorded. Values represent the mean titer of virus from triplicate dishes. In pilot experiments, virus preincubation with HBSS or with HBSS-bovine serum albumin (10 mg/ml) did not result in significant reductions of virus titers (data not shown). Error bars represent the standard error of the mean. If not shown, then the error bars were too small to graph.