Figure 2.

In vivo imaging of sporozoites in the haemolymph. (A) Left panel: An A. stephensi mosquito immobilized on a glass-slide for microscopy observation. Note the fluorescent signal at the base of the wings indicating haemolymph sporozoites (arrowhead). Right panel: An enlarged view of an A. stephensi mosquito viewed from the abdominal side indicating the fluorescent signal from sporozoites in the salivary gland (arrow) and from sporozoites in the veins of the wing (arrowhead). (B) Detection of individual sporozoites in the haemolymph. A vein of the wing imaged with a red filter (568 nm excitation) shows the auto-fluorescent mosquito tissue. The same region imaged with 488 nm excitation light shows the specific green fluorescence of the sporozoites (arrows) as well as the auto-fluorescent tissue. See also movie 1. (C) Three time-lapse images taken 3 seconds apart show the passive movement of sporozoites within the haemolymph of the mosquito tibia. The color image represents three images taken 3 seconds apart, pseudo-colored and overlayed to illustrate the movement of the sporozoites (see also movie 2). (D) Unusually many sporozoites (green) in the haemolymph of an A. albimanus thorax at 26 days post infection.