Warning: mkdir(): Permission denied in /home/virtual/lib/view_data.php on line 81
Warning: fopen(upload/ip_log/ip_log_2024-11.txt): failed to open stream: No such file or directory in /home/virtual/lib/view_data.php on line 83
Warning: fwrite() expects parameter 1 to be resource, boolean given in /home/virtual/lib/view_data.php on line 84 Ultrastructural observation of Naegleria fowleri trophozoite in mouse brain and axenic culture
Ultrastructural observation of Naegleria fowleri trophozoite in mouse brain and axenic culture
Jae-Sook Ryu,Chin-Thack Soh and Kyung-Il Im
Department of Parasitology, College of Medicine and Institute of Tropical Medicine, Yonsei University, Seoul, Korea.
Department of Parasitology, College of Medicine, Hanyang University, Seoul, Korea.
Abstract
Present study was undertaken to elucidate the changes of the ultrastructure of Naegleria fowleri trophozoite in brain tissue of mice and culture medium. Naegleria fowleri, 0359 strain, which used in this study was cultured in axenic liquid medium, CGVS medium. Each mouse was inoculated with 1 × 10(5) amoebas intranasally under secobarbital anesthesia, and sacrificed on 7th day after the infection. Comparative observation of the ultrastructure of the amoebas in axenic culture and experimentally infected mice brain was done with transmission electron microscope. The results are summarized as follows: The amoebas in mouse brain tissue were round in outline, whereas those of amoebas from axenic culture showed irregular appearance. Mitochondria in the amoebas from axenic culture was oval, round and cylindrical shape and darkly stained, whereas those of the amoebas from mouse brain tissue showed dumbbell shape together with above forms. The stain was not unique, but light and/or dark. Rough endoplasmic reticulum of amoebas in brain tissue was tubular, but from culture it was vesicular or tubular in shape. Empty vacuoles were demonstrated in amoebas from culture, while food vacuoles with myelinated structures were abundant in those from tissue, suggesting a strong phagocytic activity. Mouse brain tissue infected were extensively destroyed, and polymorphonuclear leukocytes were infiltrated predominantly with inflammatory lesion. Amoebas were observed in the vicinity of the capillary.
Figures
Figs. 1-4 Fig. 1.N. fowlerii trophozoite cultured showing two nuclei (N), vesicular endoplasmic reticulum (VER) and pseudopodial extension (P) (×7,500).
Fig. 3.N. fowlerii trophozoite cultured showing vacuole that is containing the particulated material (V) (×15,000).
Fig. 4.N. fowlerii trophozoite cultured showing vesicular endoplasmic reticulum (VER) and various shapes of mitochondria (M) (×10,000).
Figs. 5-8 Fig. 5.N. fowlerii trophozoite observed in the mouse brain tissue. The amoeba is enclosed partially by two polymorphonuclear leukocytes (PMN) and contained dumbbell shaped mitochondria (M) (×10,000).
Fig. 6.N. fowlerii trophozoite observed in the mouse brain tissue showing polysome and autophagic vacuole (AV) (×25,000).
Fig. 7.N. fowlerii trophozoite observed in the mouse brain tissue. The amoeba, that is partially disintegrated, is engulfed by a leukocyte (×12,500)
Fig. 8.N. fowlerii trophozoite observed in the mouse brain tissue showing the vacuole and its axonal contents (×20,000).
Tables
Table 1 Ultrastructural characteristics of Nagleria fowleri trophozoite
References
1.
Bowers B, Korn ED. The fine structure of Acanthamoeba castellanii. I. The trophozoite. J Cell Biol 1968;39(1):95–111.
2.
Bowers B, Korn ED. The fine structure of Acanthamoeba castellanii (Neff strain). II. Encystment. J Cell Biol 1969;41(3):786–805.
3.
Lamb D, Reid L. Histochemical and autoradiographic investigation of the serous cells of the human bronchial glands. J Pathol 1970;100(2):127–138.
4.
Cerva L. Folia Parasit 1970;17:127–133.
5.
Culbertson CG, Ensminger PW, Overton WM. Pathogenic Naegleria sp.--study of a strain isolated from human cerebrospinal fluid. J Protozool 1968;15(2):353–363.
6.
Griffin JL. Human amebic dysentery. Electron microscopy of Entamoeba histolytica contacting, ingesting, and digesting inflammatory cells. Am J Trop Med Hyg 1972;21(6):895–906.
7.
Lastovica AJ. Letter: Ultrastructure of pathogenic and non-pathogenic Naegleria amoebae. Trans R Soc Trop Med Hyg 1975;69(2):286–287.
8.
Maitra SC, Krishna Prasad BN, Das SR, Agarwala SC. Study of Naegleria aerobia by electron microscopy. Trans R Soc Trop Med Hyg 1974;68(1):56–60.
9.
Maitra SC, Krishna Prasad BN, Das SR, Agarwala SC. Ultrastructural differences of Hartmannella culbertsoni Singh and Das, 1970, in mouse brain and under different cultural conditions. Trans R Soc Trop Med Hyg 1974;68(3):229–235.
10.
Martinez AJ, Nelson EC, Jones MM, Duma RJ, Rosenblum WI. Experimental Naegleria meningoencephalitis in mice. An electron microscope study. Lab Invest 1971;25(5):465–475.
11.
Martinez J, Duma RJ, Nelson EC, Moretta FL. Experimental naegleria meningoencephalitis in mice. Penetration of the olfactory mucosal epithelium by Naegleria and pathologic changes produced: a light and electron microscope study. Lab Invest 1973;29(2):121–133.
12.
Schuster F. An Electron Microscope Study Of The Amoebo-Flagellate, Naegleria Gruberi (Schardinger). I. The Amoeboid And Flagellate Stages. J Protozool 1963;10:297–313.
13.
Schuster F. An Electron Microscope Study Of The Amoebo-Flagellate, Naegleria Gruberi (Schardinger). II. The Cyst Stage. J Protozool 1963;10:313–320.
14.
Schuster FL, Dunnebacke TH. Ultrastructural observations of experimental Naegleria meningoencephalitis in mice: intranuclear inclusions in amebae and host cells. J Protozool 1977;24(4):489–497.
15.
Vickerman K. Structural changes in mitochondria of Acanthamoeba at encystation. Nature 1960;188:248–249.
16.
Vickerman K. Patterns of cellular organisation in Limax amoebae. An electron microscope study. Exp Cell Res 1962;26:497–519.
17.
Visvesvara GS, Callaway CS. Light and electron microsopic observations on the pathogenesis of Naegleria fowleri in mouse brain and tissue culture. J Protozool 1974;21(2):239–250.
PDF Links
Full text via DOI
Download Citation 
