Figure 5

LiCPA mutant infectivity in vitro. Human monocyte cells (U937) were infected with wildtype (WT), CPA null mutants (ΔLicpa C1, ΔLicpa C2) or re-expresser clones (ΔLicpa C1::CPA, ΔLicpa C2::CPA) of L. infantum. Cell cultures were monitored for four days; results are presented as the percentage of infected macrophages and the number of amastigotes per infected cell in panels A and B, respectively. Similar experiments were performed in a canine monocyte cell line (DH82) using WT, ΔLicpa C1 and ΔLicpa C1::CPA L. infantum clones. Cell cultures were monitored for five to ten days after infection; results are presented in panels C and D. Depicted values at 96 and 120 hrs incubation are the mean of four independent experiments and error bars indicate the standard deviation. The data for the ten day incubation period is derived from one experiment, hence the absence of a standard deviation.