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Published on: February 7, 2019
ELECTRON MICROSCOPY OF LATENT PSITTACOSIS VIRUS IN MCCOY CELLS
Abstract:
Kajima, Masahiro (University of Notre Dame, Notre Dame, Ind.), Nehama Sharon, and Morris Pollard. Electron microscopy of latent psittacosis virus in McCoy cells. J. Bacteriol. 88:709-715. 1964.-Replication of psittacosis virus in McCoy cells was observed periodically by electron microscopy, and was correlated with the appearance of inclusion bodies in infected cells stained by acridine orange fluorochrome. Three well-defined morphological stages characterized the replication cycle: (i) noninfectious initial body, (ii) noninfectious intermediate body, and (iii) infectious mature or elementary body. When replication of virus was interrupted by aminopterin, the virus failed to develop beyond the noninfective initial body stage; however, after treatment of such cultures with folinic acid, intermediate and mature virus particles appeared in the cells. Latent psittacosis virus, as described here, represented a virus in which the replication process was interrupted at a noninfective (eclipse) stage of the developmental cycle.
Insights
This study reveals psittacosis virus replication in McCoy cells, detailing three morphological stages. Interruption and restoration of replication by specific compounds offer insights into latent virus development.
Area of Science:
- Microbiology
- Virology
- Cell Biology
Background:
- Psittacosis virus, a Chlamydia species, causes respiratory illness.
- Understanding viral replication is crucial for developing effective treatments.
- Latent viral infections pose significant challenges in disease management.
Purpose of the Study:
- To investigate the replication cycle of psittacosis virus in McCoy cells using electron microscopy.
- To characterize the morphological stages of psittacosis virus development.
- To explore the factors influencing the interruption and restoration of viral replication.
Main Methods:
- Electron microscopy was employed to visualize psittacosis virus within McCoy cells.
- Acridine orange fluorochrome staining was used to identify inclusion bodies.
- Viral replication was manipulated using aminopterin and folinic acid.
Main Results:
- Three distinct morphological stages of psittacosis virus replication were identified: initial, intermediate, and mature (elementary) bodies.
- Aminopterin treatment halted viral development at the initial body stage.
- Folinic acid treatment restored the development of intermediate and mature virus particles.
Conclusions:
- Latent psittacosis virus represents a state where replication is arrested at a non-infectious (eclipse) stage.
- The study elucidates the morphological dynamics of psittacosis virus replication.
- Folinic acid can overcome aminopterin-induced inhibition of psittacosis virus replication.
