Relationship between A-type and C-type particles in cells infected by Rous sarcoma virus

Area of Science:

• Virology
• Cell Biology
• Oncology

Background:

• Avian RNA tumor viruses, including Rous sarcoma virus (RSV) and Rous-associated virus (RAV), infect chicken cells.
• Cytoplasmic A-type particles are observed in infected cells, often in clusters.
• The presence and origin of these A-type particles in infected cells require further investigation.

Purpose of the Study:

• To investigate the characteristics and origin of cytoplasmic A-type particles in chicken cells infected with avian RNA tumor viruses.
• To determine the relationship between A-type particles and cellular pathology.
• To explore the immunological relationship between A-type particles and C-type viruses.

Main Methods:

• Thin section electron microscopy was used to observe A-type particles in infected chicken cells.
• Immunoelectron microscopy with monospecific antisera against viral internal proteins was applied.
• Various strains of leukosis-sarcoma viruses were used to infect cell cultures.

Main Results:

• A-type particles were observed more frequently in Rous sarcoma virus-infected cells compared to Rous-associated virus-infected cells.
• These particles were present in a small fraction of total infected cells and appeared transiently.
• Immunological analysis revealed that A-type particles contain components related to the internal proteins of C-type viruses.

Conclusions:

• The study hypothesizes that A-type particles develop in chicken cells undergoing cytopathological degeneration.
• This hypothesis explains the transient appearance of A-type particles in infected cells.
• A-type particles share immunological components with C-type viruses, suggesting a potential viral relationship.