This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ferrante, A Articles by Abell, T J Search for Related Content PubMed PubMed Citation Articles by Ferrante, A Articles by Abell, T J

Conditioned medium from stimulated mononuclear leukocytes augments human neutrophil-mediated killing of a virulent Acanthamoeba sp.

ABSTRACT

Human neutrophils in the presence of serum containing anti-amoeba antibody either lacked amoebicidal activity or were poorly amoebicidal for Acanthamoeba culbertsoni. In contrast, neutrophils preexposed for 1 h to supernatants from human peripheral blood mononuclear leukocytes (MNLs) stimulated with phytohemagglutinin demonstrated significant amoeba killing in the presence of serum containing anti-acanthamoeba antibodies. Supernatant from MNL cultured in the absence of phytohemagglutinin were not effective in stimulating significant activity in the neutrophils. Serum containing antibody promoted the adherence of many neutrophils to one amoeba. There was no significant difference between the ability of neutrophils treated with supernatants from stimulated MNLs (stimulated conditioned medium [sCM]) and supernatants from nonstimulated MNLs (nonstimulated conditioned medium [nsCM]) in their binding to acanthamoeba. The effects of sCM on neutrophils was a general phenomenon. For example, the sCM but not the nsCM enhanced the antibody-dependent neutrophil-mediated cytotoxicity against three tumor targets (K562 erythroid myeloid leukemia cell line, B16 melanoma, and P815 (DBA/2 mastocytoma). Furthermore, the sCM but not the nsCM increased the bactericidal (against Staphylococcus aureus and Streptococcus pneumoniae) and fungicidal (against Torulopsis glabrata) activity of the neutrophil. The sCM but not the nsCM contained activities which inhibited neutrophil migration and stimulated a respiratory burst in these leukocytes. These results suggest that the neutrophil antimicrobial power can be increased by exposing the leukocytes to MNL mediators.

This article has been cited by other articles:

• Clarke, D. W., Alizadeh, H., Niederkorn, J. Y. (2006). Intracorneal Instillation of Latex Beads Induces Macrophage-Dependent Protection against Acanthamoeba Keratitis. IOVS 47: 4917-4925 [Abstract] [Full Text]  
• Clarke, D. W., Alizadeh, H., Niederkorn, J. Y. (2005). Failure of Acanthamoeba castellanii to Produce Intraocular Infections. IOVS 46: 2472-2478 [Abstract] [Full Text]  
• Marciano-Cabral, F., Cabral, G. (2003). Acanthamoeba spp. as Agents of Disease in Humans. Clin. Microbiol. Rev. 16: 273-307 [Abstract] [Full Text]  
• Mattana, A., Cappai, V., Alberti, L., Serra, C., Fiori, P. L., Cappuccinelli, P. (2002). ADP and Other Metabolites Released from Acanthamoeba castellanii Lead to Human Monocytic Cell Death through Apoptosis and Stimulate the Secretion of Proinflammatory Cytokines. Infect. Immun. 70: 4424-4432 [Abstract] [Full Text]