Figure 1.

Characterization of L₆E₉ cell infection by four T. cruzi strains. Giemsa staining of L₆E₉ cells after 72 hours of infection with (A) Y, (B) CL, (C) Brazil, and (D) Tulahuen strains of T. cruzi was performed. All strains studied successfully infected the myoblasts, and at 72 hours post infection (hpi), it was possible to observe amastigote forms in the host cell's cytoplasm as shown in details in A inset. (Bars = 50 μm.) To confirm genetic background of the parasite stocks used for infection, genomic DNA from epimastigote forms was isolated and amplified with Multiplex PCR with primers derived from a hypervariable region of the T. cruzi mini exon. (E) The Y, CL, and Tulahuen strains had a PCR product of 250 bp, indicating that they belong to the T. cruzi (TC) II family, and the Brazil strain had a 200-bp product, indicating that it belongs to TC I family.