Skip to main content
PMC home page
Infection and Immunity logoLink to Infection and Immunity
. 1996 Jun;64(6):2336–2338. doi: 10.1128/iai.64.6.2336-2338.1996

Influence of opsonization conditions on C3 deposition and phagocyte binding of large- and small-capsule Cryptococcus neoformans cells.

T R Kozel 1, A Tabuni 1, B J Young 1, S M Levitz 1
PMCID: PMC174075  PMID: 8675346

Abstract

Previous studies demonstrated that, following opsonization with normal human serum (NHS), phagocytes bind greater numbers of small-capsule Cryptococcus neoformans cells than yeast cells with large capsules. The present study tested the hypothesis that suboptimal deposition of opsonic C3 fragments contributes to this disparity. C neoformans was grown under conditions promoting large or small capsules and was incubated at various concentrations in NHS. At low concentrations of yeast cells (125 cells per microl of NHS), the deposition of C3 fragments per unit of capsule volume and the binding of yeast cells to cultured human monocytes were similar for yeast cells having large and small capsules. However, at higher cell concentrations, large-capsule cells exhibited suboptimal coating with C3 fragments and markedly diminished monocyte binding compared with small-capsule cells. Thus, the inverse correlation between capsule size and phagocyte binding can be overcome by conditions promoting optimal C3 deposition.

Full Text

The Full Text of this article is available as a PDF (218.7 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bulmer G. S., Sans M. D. Cryptococcus neoformans. 3. Inhibition of phagocytosis. J Bacteriol. 1968 Jan;95(1):5–8. doi: 10.1128/jb.95.1.5-8.1968. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bulmer G. S., Sans M. D. Cryptococcus neoformans. II. Phagocytosis by human leukocytes. J Bacteriol. 1967 Nov;94(5):1480–1483. doi: 10.1128/jb.94.5.1480-1483.1967. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Chuck S. L., Sande M. A. Infections with Cryptococcus neoformans in the acquired immunodeficiency syndrome. N Engl J Med. 1989 Sep 21;321(12):794–799. doi: 10.1056/NEJM198909213211205. [DOI] [PubMed] [Google Scholar]
  4. Collins H. L., Bancroft G. J. Cytokine enhancement of complement-dependent phagocytosis by macrophages: synergy of tumor necrosis factor-alpha and granulocyte-macrophage colony-stimulating factor for phagocytosis of Cryptococcus neoformans. Eur J Immunol. 1992 Jun;22(6):1447–1454. doi: 10.1002/eji.1830220617. [DOI] [PubMed] [Google Scholar]
  5. Davies S. F., Clifford D. P., Hoidal J. R., Repine J. E. Opsonic requirements for the uptake of Cryptococcus neoformans by human polymorphonuclear leukocytes and monocytes. J Infect Dis. 1982 Jun;145(6):870–874. doi: 10.1093/infdis/145.6.870. [DOI] [PubMed] [Google Scholar]
  6. Diamond R. D., May J. E., Kane M. A., Frank M. M., Bennett J. E. The role of the classical and alternate complement pathways in host defenses against Cryptococcus neoformans infection. J Immunol. 1974 Jun;112(6):2260–2270. [PubMed] [Google Scholar]
  7. Granger D. L., Perfect J. R., Durack D. T. Virulence of Cryptococcus neoformans. Regulation of capsule synthesis by carbon dioxide. J Clin Invest. 1985 Aug;76(2):508–516. doi: 10.1172/JCI112000. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Griffin F. M., Jr Roles of macrophage Fc and C3b receptors in phagocytosis of immunologically coated Cryptococcus neoformans. Proc Natl Acad Sci U S A. 1981 Jun;78(6):3853–3857. doi: 10.1073/pnas.78.6.3853. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Kozel T. R., Mastroianni R. P. Inhibition of phagocytosis by cryptococcal polysaccharide: dissociation of the attachment and ingestion phases of phagocytosis. Infect Immun. 1976 Jul;14(1):62–67. doi: 10.1128/iai.14.1.62-67.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Kozel T. R., Pfrommer G. S., Guerlain A. S., Highison B. A., Highison G. J. Strain variation in phagocytosis of Cryptococcus neoformans: dissociation of susceptibility to phagocytosis from activation and binding of opsonic fragments of C3. Infect Immun. 1988 Nov;56(11):2794–2800. doi: 10.1128/iai.56.11.2794-2800.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Kozel T. R., Wilson M. A., Pfrommer G. S., Schlageter A. M. Activation and binding of opsonic fragments of C3 on encapsulated Cryptococcus neoformans by using an alternative complement pathway reconstituted from six isolated proteins. Infect Immun. 1989 Jul;57(7):1922–1927. doi: 10.1128/iai.57.7.1922-1927.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Levitz S. M., Dupont M. P. Phenotypic and functional characterization of human lymphocytes activated by interleukin-2 to directly inhibit growth of Cryptococcus neoformans in vitro. J Clin Invest. 1993 Apr;91(4):1490–1498. doi: 10.1172/JCI116354. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Levitz S. M., Farrell T. P. Growth inhibition of Cryptococcus neoformans by cultured human monocytes: role of the capsule, opsonins, the culture surface, and cytokines. Infect Immun. 1990 May;58(5):1201–1209. doi: 10.1128/iai.58.5.1201-1209.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Levitz S. M., Tabuni A. Binding of Cryptococcus neoformans by human cultured macrophages. Requirements for multiple complement receptors and actin. J Clin Invest. 1991 Feb;87(2):528–535. doi: 10.1172/JCI115027. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Levitz S. M., Tabuni A., Kornfeld H., Reardon C. C., Golenbock D. T. Production of tumor necrosis factor alpha in human leukocytes stimulated by Cryptococcus neoformans. Infect Immun. 1994 May;62(5):1975–1981. doi: 10.1128/iai.62.5.1975-1981.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Macher A. M., Bennett J. E., Gadek J. E., Frank M. M. Complement depletion in cryptococcal sepsis. J Immunol. 1978 May;120(5):1686–1690. [PubMed] [Google Scholar]
  17. Mitchell T. G., Friedman L. In vitro phagocytosis and intracellular fate of variously encapsulated strains of Cryptococcus neoformans. Infect Immun. 1972 Apr;5(4):491–498. doi: 10.1128/iai.5.4.491-498.1972. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Swenson F. J., Kozel T. R. Phagocytosis of Cryptococcus neoformans by normal and thioglycolate-activated macrophages. Infect Immun. 1978 Sep;21(3):714–720. doi: 10.1128/iai.21.3.714-720.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Young B. J., Kozel T. R. Effects of strain variation, serotype, and structural modification on kinetics for activation and binding of C3 to Cryptococcus neoformans. Infect Immun. 1993 Jul;61(7):2966–2972. doi: 10.1128/iai.61.7.2966-2972.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Infection and Immunity are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES