Ultrastructural features of DEN2 virus-infected monocytes. "Acinar" like structure. A and B show empty spaces surrounded by monocytes. (A bar 1 μm; B bar: 2 μm). C) In some instances, a moderated electron dense material also delimited the empty space (bar: 1 μm) D) Inset from C shows a lineal electron dense material (large arrow) delimiting the empty space, beyond viral particles (small arrow) and a monocyte are observed (bar: 200 nm).