Influence of Molecular Sizes of Cryptococcus neoformans Capsular Polysaccharide on Phagocytosis

Akira Yasuoka, Hiroshi Yamada, Mitsuo Kaku, Hironobu Koga, Shigeru Kohno

Research output: Contribution to journalArticlepeer-review

28 Citations (Scopus)


The role of capsular polysaccharides (CPS) of Cryptococcus neoformans in phagocytosis by murine alveolar macrophages was investigated in four strains of C. neoformans serotype A, YC-11, YC-5, YC-27 and YC-13. Phagocytosis rates increased markedly after adding 10% mouse serum, compared to fetal calf serum. The reverse relation between capsular thickness of C. neoformans and phagocytosis by alveolar macrophages was observed except in YC-27, which had thin capsules and high virulence. The phagocytosis rate in mice serum was 17.3% in YC-11 (capsule thickness 2.8–3.5 μm), 39.8% in YC-5 (capsule size 0.81.5 μm), 20.3% in YC-27 (capsule size 0.6–1.1 μm), and 62.8% in YC-13 (capsule not detected microscopically). The CPS of YC-11, YC-5, and YC-27 analyzed by gel-filtration using CL-2B showed high molecular fractions near the void volume. However, the CPS of YC-13 showed only low molecular fractions. The widely eluted CPS of YC-11 was separated into 3 fractions and each fraction was added in the phagocytosis assay of YC-13. Phagocytosis was markedly suppressed particularly by the addition of a higher molecular fraction. These results suggest that phagocytosis of C. neoformans by alveolar macrophages is influenced by the molecular sizes of the CPS.

Original languageEnglish
Pages (from-to)851-856
Number of pages6
Issue number11
Publication statusPublished - 1994


  • Antiphagocytic activity
  • Capsular polysaccharide
  • Cryptococcus neoformans
  • Murine
  • alveolar macrophage

ASJC Scopus subject areas

  • Microbiology
  • Immunology
  • Virology


Dive into the research topics of 'Influence of Molecular Sizes of Cryptococcus neoformans Capsular Polysaccharide on Phagocytosis'. Together they form a unique fingerprint.

Cite this