Embedding and Staining Ameboid Forms

Abstract

The cytochemical evaluation of experimentally treated amebae requires preparative technics which do not involve extraneous material. For such work, the following simple and rapid modifications of standard procedures allowing a high recovery have been devised: embedding amebae in bulk; embedding small numbers; preservation of whole mounts; and, staining of whole mounts. For embedding in bulk, the amebae are fixed, dehydrated, and cleared in a centrifuge tube. The tube is initially lined with paraffin, in order to recover the amebae which on dehydration adhere to the sides. The addition of xylene both clears, and by dissolving the paraffin, releases the adherent amebae. The cleared amebae are finally transferred from the centrifuge tube to a depression slide for embedding. In the staining of whole mounts as well as the embedding of small numbers of amebae, the entire procedure is carried out under a dissecting microscope, the amebae remaining in the same conical depression slide throughout each of the procedures. The use of micro-capillary pipettes for changing reagents further insures against loss of amebae. In order to exemplify the above procedure for staining whole mounts, a detailed description for the Feulgen technic is presented. A simple procedure for preserving whole mounts involves fixation, dehydration and embedding on a slide. The reagents are added with a pipette, and are removed by tilting the slide. The whole mounts may be stored in this condition.