21. In the host, WSSV infects a wide variety of cells from ectodermal and mesodermal origin. 22. The esca is ectodermal in origin whereas the barbel organs may be derived from the mesoderm. 23. Cells from both the mesodermal and the ectodermal tissues contribute to the formation of the eye. 24. This is similar to the embryonic apical ectodermal ridge, which forms during normal limb development. 25. The animal cap forms the roof of the blastocoele and goes on primarily to form ectodermal derivatives. 26. A major focus is basic investigation of ectodermal appendage development and the study of human ectodermal dysplasias. 27. A major focus is basic investigation of ectodermal appendage development and the study of human ectodermal dysplasias. 28. Now, as the ectoderm continues to elongate, the ectodermal cells of the neural plate fold inward. 29. Another cadherin, E-cadherin, is expressed by ectodermal cells in the process of neural plate development. 30. Unlike the larger tracheae which are derived of ectodermal stem cells, tracheoles do not molt with the insect.
