Development of Eimeria nieschulzi (Coccidia, Apicomplexa) Gamonts and Oocysts in Primary Fetal Rat Cells

Figure 3

In situ localization of intestinal stages and third-generation merozoites. (a) FITC/DAPI overlay of B1C4 antibody probed section at 72 h p.i. Fluorescence signals are limited to the middle and upper part of the crypts but were absent in the villi. Bar 200 μm. (b) FITC/DAPI overlay of B1C4 antibody probed section at 72 h p.i at higher magnification shows multinuclear schizonts. Bar 25 μm. (c) Transmitted light (TL) micrograph of third-generation merozoites. At this time of infection they are characterized with a length of more than 25 μm and a straight cell shape and were found in the intestine at 117 h p.i. Bar 25 μm. (d) TL micrograph of B1C4 probed section at 120 h p.i., the enzymatic reaction of the secondary antibody linked peroxidase can be found in the lower and middle parts of the crypts (c). Signals are absent in the villi (v). musc: muscularis; submuc: submucosa; muc: mucosa. Bar 200 μm (e) TL micrograph shows antibody derived peroxidase reaction in schizonts of the third-generation in the middle part of the crypts at 120 h p.i. The schizonts contain approximately 12 merozoites. Bar 50 μm. (f) TL micrograph shows schizonts of different shapes and sizes at 120 h p.i. The asterisk designates a schizont which contained more than 12 merozoites and probably belongs to the second-generation schizont considering the stages occurred in vitro. Bar 25 μm. (g) FITC labelled parasite stages at 144 h p.i. are visible in larger clusters in the middle and upper parts of the crypts, and at the base of the atrophied villi. Bar 200 μm. (h) Higher magnifications revealed mono- and multinuclear stages (FITC/DAPI overlay). The mononuclear stages (hash key) are probably early macrogamonts and similar to them observed in vitro. The multinuclear stages (asterisk) are probably schizonts of the fourth generation, because the localization of nuclei is not limited to the periphery. The corresponding DAPI image can be found in Supplementary Figure 2 (see Supplementary Material available online at http://dx.doi.org/10.1155/2013/591520). Bar 50 μm.