Morphology and three-dimensional reconstruction of the digestive system of Dermatophagoides farinae

The digestive system of Dermatophagoides farinae remains poorly documented.

In this study, a three-dimensional (3-D) model of the alimentary canal of D. farinae was built for the first time based on hematoxylin-eosin staining, 76 cross-sections of the adult mite and 3-D reconstruction technology.

Spatially, the system included the prebuccal cavity, foregut, midgut, hindgut, anus and salivary gland. The prebuccal cavity was surrounded by gnathosoma; the foregut was composed of a muscular pharynx and an esophagus passing through the brain; the midgut was divided into an anterior midgut with a pair of ceca and a posterior midgut; the hindgut consisted of a relatively broad colon and a narrow rectum, and the salivary gland was irregular in shape and located in front of the brain. The 3-D images of the individual external surfaces of the reconstructed alimentary canal were displayed and the human-computer interaction was realized by performing arbitrary rotation and random sectioning.

The 3-D model of the alimentary canal of D. farinae presented in this paper provides a stereoscopic view to study the adjacent relationship and arrangement of respective gut sections in the intact mite. This study has implicit impact on morphology studies, immunohistochemistry, as well as in situ PCR and localization of the allergen in dust mites.