Related Experiment Video
Updated: Aug 4, 2026
Particle Agglutination Method for Poliovirus Identification
Published on: April 20, 2011
Sequence of morphological changes in epithelial cell cultures infected with poliovirus
Abstract:
A sequential study is reported of the cytological changes induced in cultures of monkey kidney epithelial cells by poliovirus. The pattern of cytological changes was followed through a single cycle of virus multiplication. Morphological alterations were correlated with the appearance of new infective virus within the cells and in the culture fluid. Alteration of the chromatin pattern of the nucleus, and Type B acidophilic intranuclear inclusions, were seen as early as 4 hours after virus inoculation. Later wrinkling and shrivelling of the nucleus occurred, and eosinophilic cytoplasmic masses appeared. The rounded, pycnotic cell, customarily used as an index of the cytopathic response, was found only during the last stages of the infective process. On the basis of these changes, infected cells could be classified into six different types. Differential cell counts were made on the stained cultures, and the stage of cytopathic degeneration was correlated with the appearance of virus in the cells and in the culture fluid. Newly formed virus could be detected within the infected cells at about the same time that the first nuclear alterations and intranuclear inclusions were seen. The virus-induced morphological changes exhibited a specificity distinct from the classical pycnosis of autolytic degeneration.
Insights
This study details poliovirus-induced cytological changes in monkey kidney cells, revealing early nuclear alterations and intranuclear inclusions that precede typical cell death. These specific changes help classify infected cells and track virus multiplication.
Area of Science:
- Virology
- Cell Biology
- Pathology
Background:
- Poliovirus infection causes significant cytopathic effects in host cells.
- Understanding the sequential cytological changes is crucial for characterizing viral pathogenesis.
Purpose of the Study:
- To sequentially document and correlate cytological alterations in monkey kidney epithelial cells with poliovirus multiplication.
- To identify early and specific morphological markers of poliovirus infection.
Main Methods:
- Sequential observation of cytological changes in cultured monkey kidney cells infected with poliovirus.
- Correlation of morphological alterations with the detection of infectious virus.
- Classification of infected cells based on observed cytopathic changes.
Main Results:
- Early alterations include nuclear chromatin changes and Type B intranuclear inclusions (4 hours post-inoculation).
- Later changes involve nuclear wrinkling, cytoplasmic masses, and cell rounding (late stage).
- Newly formed poliovirus detected concurrently with initial nuclear changes and inclusions.
Conclusions:
- Poliovirus-induced cytological changes are distinct from autolytic degeneration.
- Early nuclear and intranuclear alterations serve as specific indicators of poliovirus infection.
- A six-type classification system for infected cells was proposed based on observed cytopathic effects.
