Related Experiment Video
Updated: Jan 21, 2026
07:42
Using Fluorescent Proteins to Visualize and Quantitate Chlamydia Vacuole Growth Dynamics in Living Cells
Published on: October 13, 2015
7.9K
Enumeration of Viable Chlamydia from Infected Animals Using Immunofluorescent Microscopy
Steven Liang1, James B Mahony2
1Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada.
Methods in Molecular Biology (Clifton, N.J.)
|August 7, 2019
Summary
Quantifying viable Chlamydia trachomatis in infected mice is crucial for vaccine development. This study details a culture-based method using immunofluorescent microscopy to accurately count infectious bacteria.
Area of Science:
- Microbiology
- Immunology
- Vaccinology
Background:
- Accurate quantification of infectious Chlamydia is vital for vaccine efficacy studies.
- Current non-culture methods cannot distinguish between viable and nonviable Chlamydia organisms.
- Chlamydia's obligate intracellular nature complicates viability assessment.
Purpose of the Study:
- To develop and describe a method for enumerating viable Chlamydia trachomatis in infected animal models.
- To provide a reliable technique for vaccine evaluation by assessing infectious load.
Main Methods:
- Collection of vaginal swabs from Chlamydia-infected mice.
- Culturing swabs on McCoy cells to allow Chlamydia replication.
- Enumeration of viable Chlamydia by counting intracellular inclusions using immunofluorescent microscopy.
Main Results:
- Successful enumeration of viable Chlamydia trachomatis from infected mouse vaginal swabs.
- Demonstration of a culture-based method capable of differentiating viable from nonviable organisms.
- Establishment of a quantifiable measure of infectious Chlamydia load.
Conclusions:
- Culture combined with immunofluorescent microscopy provides an effective means to quantify viable Chlamydia trachomatis.
- This method is essential for accurate evaluation of Chlamydia vaccines in animal models.
- The described technique addresses limitations of non-culture-based diagnostic methods.
Related Concept Videos
01:12Immunofluorescence Microscopy
13.0K
A fluorescence microscope uses fluorescent chromophores called fluorochromes, which can absorb energy from a light source and then emit this energy as visible light. Fluorochromes include naturally fluorescent substances (such as chlorophylls) and fluorescent stains that are added to the specimen to create contrast. Dyes such as Texas red and FITC are examples of fluorochromes. Other examples include the nucleic acid dyes 4’,6’-diamidino-2-phenylindole (DAPI), and acridine orange.
13.0K
01:29Bacterial Phylum Chlamydiae
436
The phylum Chlamydiae or Chlamydiota is composed of a single order, Chlamydiales. This phylum consists entirely of obligate intracellular parasites that infect eukaryotic hosts. While human pathogens within this group have been studied extensively, the phylum encompasses many species capable of interacting with various eukaryotic organisms. Members of Chlamydiae are typically small cocci, approximately 0.5 μm in diameter, and exhibit a distinctive developmental cycle. As is characteristic...
436
00:59Tonicity in Animals
123.3K
The tonicity of a solution determines if a cell gains or loses water in that solution. The tonicity depends on the permeability of the cell membrane for different solutes and the concentration of nonpenetrating solutes in the solution within and outside of the cell. If a semipermeable membrane hinders the passage of some solutes but allows water to follow its concentration gradient, water moves from the side with low osmolarity (i.e., less solute) to the side with higher osmolarity (i.e.,...
123.3K
01:16Tonicity in Animals
5.1K
Tonicity describes the amount of solute in a solution. The measure of the tonicity of a solution, or the total amount of solutes dissolved in a specific amount of solution, is called its osmolarity. Three terms—hypotonic, isotonic, and hypertonic—are used to relate the osmolarity of a cell to the osmolarity of the extracellular fluid that contains the cells. In a hypotonic solution, such as tap water, the extracellular fluid has a lower concentration of solutes than the fluid inside...
5.1K
02:59Animal Mitochondrial Genetics
9.0K
Among all the organelles in an animal cell, only mitochondria have their own independent genomes. Animal mitochondrial DNA is a double-stranded, closed-circular molecule with around 20,000 base pairs. Mitochondrial DNA is unique in that one of its two strands, the heavy, or H, -strand is guanine rich, whereas the complementary strand is cytosine rich and called the light, or L, -strand. Compared to nuclear DNA, mitochondrial DNA has a very low percentage of non-coding regions and is marked by...
9.0K
01:20Infection
12.0K
When a pathogen enters the body and reproduces, it can cause an infection, damage body cells, and cause illness symptoms that eventually lead to disease. Therefore, its prevention requires breaking the chain of infection.
The chain begins with pathogens: bacteria, viruses, fungi, prions, or parasites such as protozoa helminths. These can be present on the skin as transient or resident flora, or they can be acquired from the environment. Identifying and treating the type of infection and...
The chain begins with pathogens: bacteria, viruses, fungi, prions, or parasites such as protozoa helminths. These can be present on the skin as transient or resident flora, or they can be acquired from the environment. Identifying and treating the type of infection and...
12.0K