Related Experiment Videos
[Inapparent persistent chlamydial infection in McCoy cells]
Abstract:
We have studied the phenomena of inapparent chlamydial infections in vitro using McCoy cells in culture as hosts and low doses of Chlamydia psittaci (GP-IC) as infecting agents. The results indicate that GP-IC can persist undetected at least 220 hrs in McCoy cells previously inoculated with 0.2 mL of a GP-IC preparation containing 30 ifu/mL, using the centrifuge-assisted inoculation technique. These cells were maintained in complete MEM medium supplemented with 2% v/v of foetal bovin serum (FBS). These inapparent chlamydial infections did not follow active infections (detectable chlamydial multiplication); however, they could be induced to active infections (formation of intracytoplasmic inclusions) by transfering the infected McCoy cells in complete MEM medium supplemented with 5% v/v of FBS and 1 microgram/mL of cycloheximide. Transfer of these cells in complete MEM medium supplemented with 5% v/v of FBS but without cycloheximide did not induce active infections indicating that nutritional competition was not implicated in these inapparent chlamydial infections since that medium usually support chlamydial multiplication.
Insights
Inapparent chlamydial infections were studied in McCoy cells using low doses of Chlamydia psittaci (GP-IC). These persistent, undetected infections could be reactivated into active infections with specific medium and cycloheximide.
Area of Science:
- Microbiology
- Cell Biology
- Infectious Diseases
Context:
- Chlamydial infections can establish inapparent states within host cells.
- McCoy cells are a common model for studying Chlamydia propagation.
- Understanding persistent infections is crucial for disease management.
Purpose:
- To investigate the characteristics of inapparent chlamydial infections in vitro.
- To determine the conditions required to induce active infection from an inapparent state.
- To explore the role of host cell environment in chlamydial persistence.
Summary:
- Low doses of Chlamydia psittaci (GP-IC) established inapparent infections in McCoy cells, persisting for over 220 hours.
- These infections remained undetected without active multiplication.
- Reactivation to active infection (intracellular inclusions) was achieved by transferring cells to medium with 5% FBS and cycloheximide.
Impact:
- Demonstrates a method for inducing active chlamydial infections from persistent, inapparent states.
- Highlights the role of specific cellular conditions in Chlamydia lifecycle manipulation.
- Provides insights into Chlamydia persistence mechanisms, potentially aiding therapeutic strategies.