Related Experiment Video

Updated: May 3, 2026

Macrophage Cholesterol Depletion and Its Effect on the Phagocytosis of Cryptococcus neoformans
11:07

Macrophage Cholesterol Depletion and Its Effect on the Phagocytosis of Cryptococcus neoformans

Published on: December 19, 2014

12.2K

Cryptococcal cell morphology affects host cell interactions and pathogenicity

Laura H Okagaki1, Anna K Strain, Judith N Nielsen

  • 1Department of Microbiology, Medical School, University of Minnesota, Minneapolis, Minnesota, United States of America.

Plos Pathogens
|June 30, 2010
PubMed

Insights

Cryptococcus neoformans can dramatically enlarge in vivo, evading immune cells and increasing survival. This fungal cell enlargement is a novel mechanism for pathogen survival during infection.

Area of Science:

  • Mycology
  • Infectious Diseases
  • Cell Biology

Background:

  • Cryptococcus neoformans is a significant human fungal pathogen.
  • This pathogen typically exists as 5-10 micrometer cells.
  • Infection can lead to severe outcomes, including meningoencephalitis.

Purpose of the Study:

  • To investigate the phenomenon of cryptococcal cell enlargement in vivo.
  • To understand the impact of cell size changes on fungal pathogenicity.
  • To elucidate the mechanisms underlying cryptococcal cell enlargement and survival.

Main Methods:

  • In vivo observation of Cryptococcus neoformans cell morphology.
  • Assessment of phagocytosis by host mononuclear cells.
  • Evaluation of resistance to oxidative and nitrosative stress.
  • Analysis of fungal cell DNA content and ploidy.

Main Results:

  • Cryptococcus neoformans cells enlarged up to 100 microm in vivo.
  • Enlarged cells exhibited reduced phagocytosis and increased stress resistance.
  • Cell enlargement was associated with decreased central nervous system penetration.
  • Enlarged cells were identified as polyploid and uninucleate, capable of producing daughter cells.

Conclusions:

  • Cryptococcal cell enlargement is a novel survival mechanism.
  • Morphological changes allow evasion of host immune defenses.
  • This phenomenon facilitates pathogen survival during early infection stages.

More Related Videos

Size Matters: Measurement of Capsule Diameter in Cryptococcus neoformans08:24

Size Matters: Measurement of Capsule Diameter in Cryptococcus neoformans

Published on: February 27, 2018

13.5K
Complementary Use of Microscopic Techniques and Fluorescence Reading in Studying Cryptococcus-Amoeba Interactions10:56

Complementary Use of Microscopic Techniques and Fluorescence Reading in Studying Cryptococcus-Amoeba Interactions

Published on: June 22, 2019

5.8K

Related Concept Videos

Microbial Morphologies01:29

Microbial Morphologies

Bacterial and archaeal cells exhibit remarkable diversity in shape and structure, critical in their adaptability and functionality. Among bacteria, the most commonly observed shapes include cocci and bacilli. Cocci are spherical and may exist singly or in groupings such as pairs (diplococci), chains (streptococci), clusters (staphylococci), or tetrads. Bacilli, in contrast, are rod-shaped and can also occur as single cells, in pairs, or chains, depending on their environmental and genetic...
4.8K
Overview of Fungi01:29

Overview of Fungi

Fungi are a diverse group of eukaryotes more closely related to animals than other eukaryotes. Fungal cell walls comprise chitin, a polysaccharide that provides structural strength, and glucans, which contribute to flexibility and integrity. Other polysaccharides, such as mannans and galactosans, may supplement or replace chitin in some fungi. These adaptations, along with their preference for acidic environments and tolerance for high osmotic pressure, enable fungi to thrive in various...
2.4K
Fungal Group Zygomycota01:29

Fungal Group Zygomycota

Zygomycota, previously classified as a distinct fungal group, are primarily terrestrial, saprophytic molds that play a crucial role as decomposers. Recent phylogenetic studies have revealed that these fungi are now divided into two major clades — Mucoromycota, which includes many symbiotic species, and Zoopagomycota, which primarily consists of parasitic and pathogenic fungi. These groups exhibit distinct ecological roles and reproductive strategies while sharing key structural and...
2.1K
Fungal Phylum Microsporidia01:28

Fungal Phylum Microsporidia

Microsporidia are a group of obligate intracellular fungi that were initially classified as protists but were later reclassified based on phylogenetic, molecular, and structural evidence linking them to the Chytridiomycota. These unicellular, non-motile organisms are highly specialized parasites that infect a wide range of animal hosts, including humans. They have evolved extensive genomic and metabolic reductions, making them highly dependent on their hosts for survival.Morphology and Genomic...
782
Colonisation of Pathogens01:25

Colonisation of Pathogens

Pathogen colonization of host tissues is a critical step in the development of infectious diseases. Various pathogenic microorganisms, including bacteria, fungi, viruses, and protozoa, have evolved complex strategies to attach to, invade, and persist within host environments. These mechanisms enable pathogens to establish infections, evade immune responses, and resist antimicrobial treatments.Attachment to Host CellsIn bacteria, colonization typically begins with adherence to host epithelial...
77
Antifungal Agents01:15

Antifungal Agents

Amphotericin B is a broad-spectrum antifungal agent that exploits structural differences between fungal and mammalian cell membranes. Its amphipathic structure—featuring a hydrophobic polyene-lactone ring and a hydrophilic region containing mycosamine and carboxylic acid groups—enables selective binding to ergosterol, a sterol predominantly found in fungal plasma membranes. This selective interaction underlies the drug’s antifungal activity, although weak binding to...
119