Figure 6.

Infection of mouse macrophages with lack-targeted L. major in vitro. BALB/c bone marrow–derived macrophages were incubated with indicated lack-targeted L. major promastigotes using three parasites per macrophage. After 16 h at 35°C, the monolayers were washed to remove extracellular parasites and stained immediately (A), or washed and then incubated for an additional 80 h at 35°C and stained (B). Monolayers were scored for frequency (percent) of macrophages infected with either five or more amastigotes (5+), one to four amastigotes (1–4), or uninfected (0). In C, mean numbers of intracellular amastigotes per 100 macrophages are indicated at 16 and 96 h after infection using the indicated organisms. For each infection, ∼200 macrophages were analyzed. Data are averages from two experiments.