Transmission modes of <i>Pneumocystis carinii</i> among rats observed by karyotype analysis

, Hong, S T; , Ryu, J S; , Chai, J Y; , Lee, S H

doi:1992.30.4.283

Korean J Parasito > Volume 30(4):1992 > Article

Original Article


Korean J Parasitol. 1992 Dec;30(4):283-288. English. Published online Mar 20, 1994. http://dx.doi.org/10.3347/kjp.1992.30.4.283
Copyright © 1992 by The Korean Society for Parasitology


Transmission modes of Pneumocystis carinii among rats observed by karyotype analysis
S T Hong,J S Ryu,J Y Chai and S H Lee
Department of Parasitology and Institute of Endemic Diseases, Seoul National University College of Medicine, Seoul 110-799, Korea.


Abstract
To observe the transmission patterns of karyotype of Pneumocystis carinii (Pc) by rat colonies, three strains of rats, Sprague-Dawley(SD), Wistar(W) and Fisher(F) from various animal vendors, were suppressed of their immunity by injection of methyl prednisolone. They were kept for 5 to 13 weeks in 3 different animal rooms, A, B, and C. The purified organisms were prepared in low melting point agarose gel by embedded lysis method for pulsed field gel electrophoresis. Field inversion gel electrophoresis showed 2 patterns of the karyotype of Pc. The rooms A and C contained SD rats from the source P, and also the room A was used for F and W rats. However, Pc from all of the SD and F rats in the room A showed same karyotypes, the pattern I. The SD rats from different vendors, M and S, were reared in the room B, and shared the same Pc karyotypes, the pattern II. The rats of W strain were from the vendor M, and immune-suppressed in the animal room A. Five weeks after the experiment, the Pc showed the karyotype pattern II but the pattern became mixed with the type I after 7 to 8 weeks. The findings revealed that the animals born and reared in the same animal quarter harbored Pc with same karyotypes. If the animals were kept under immune-suppression in the same room with heavily infected hosts, they could be infected by Pc from their neighbors. The present experimental findings suggest that Pc is transmitted among rats through the air.

Figures


	Fig. 1 The FIGE gel run under conditions of 1% agarose, 50 sec forward and 25 sec backward, 110V 96 hrs, and 1/2X TBE buffer 14℃. Loaded samples are, 1. Size marker Saccharomyces cerevisiae AB 972; 2. F2; 3. F3-1; 4. F12; 5. F13-1; 6. F14; 7. F15. All of the Fisher rats were kept in the room A, but F2, F12, and F13-1 were from the animal room P and F3-1, F14, and F15 were from K.


	Fig. 2 The FIGE gel run under conditions of 1% agarose, 50 sec forward and 25 sec backward, 95 V, 120 hrs, and 1/2X TBE buffer 14℃. Loaded samples are 1. Size marker Saccharomyces cerevisiae AB 972; 2. F19; 3. F14; 4. SD30-6; 5. SD28; 6. SPF; 7. W13-3; 8. W13-20; 9. Size marker as lane 1.


	Fig. 3 The FIGE gel run under conditions of 1% agarose, 50 sec forward and 25 sec backward, 95 V, 96 hrs, and 1/2X TBE buffer 14℃. Loaded samples are 1. Size marker Saccharomyces cerevisiae AB 972; 2. F19; 3. F2; 4. SD28; 5. SD32; 6. SPF1; 7. D30-6. W13-3; 9. W13-20; 10. W13-32.


	Fig. 4 Karyotypcs of P. carinii showing the patterns I, II, and the mixed one. The pattern I was found in the room A, and the pattern II was in the room B.

Tables


	Table 1 Albino rats used for Pc infection in 3 animal rooms

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