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Forward Genetic Approaches in Chlamydia trachomatis
09:03

Forward Genetic Approaches in Chlamydia trachomatis

Published on: October 23, 2013

Plaque formation by Chlamydia in L cells

J Banks1, B Eddie, J Schachter

  • 1The G. W. Hooper Foundation, University of California San Francisco Medical Center, San Francisco, California 94122.

Infection and Immunity
|March 1, 1970
PubMed

Insights

Chlamydia can form plaques in cell cultures, with mouse fibroblast cells showing the highest sensitivity. This plaque assay offers a sensitive method for measuring chlamydial infectivity, comparable to traditional egg-based methods.

Area of Science:

  • Microbiology
  • Cell Biology
  • Infectious Diseases

Background:

  • Chlamydiae are obligate intracellular bacteria known to infect various hosts.
  • Accurate measurement of chlamydial infectivity is crucial for understanding pathogenesis and developing treatments.
  • Traditional methods like egg LD50 determination have limitations in sensitivity and practicality.

Purpose of the Study:

  • To investigate the ability of Chlamydiae to produce plaques in cell culture.
  • To identify the most sensitive cell line for chlamydial plaque formation.
  • To compare the sensitivity of the plaque assay with established methods for chlamydial infectivity determination.

Main Methods:

  • Infection of various cell lines with Chlamydiae.
  • Observation and characterization of plaque formation.
  • Comparison of plaque titration with egg LD50 determination for quantifying chlamydial infectivity.

Main Results:

  • Chlamydiae successfully produced plaques in multiple cell lines.
  • Mouse fibroblast L-929 cells demonstrated the highest sensitivity and plaque clarity.
  • The plaque assay exhibited sensitivity comparable to or exceeding egg LD50 determination.

Conclusions:

  • The plaque assay is a highly sensitive and reproducible method for quantifying chlamydial infectivity.
  • Mouse fibroblast L-929 cells are optimal for this chlamydial plaque assay.
  • This assay provides a valuable tool for research requiring precise measurement of chlamydial infectivity, excluding only slow-growing trachoma-inclusion-conjunctivitis agents.

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