Phagocytosis, neutrophils

A common characteristic of most CNS bacterial pathogens (e.g., H. influenzae, Escherichia coli, and N. meningitidis) is the presence of an extensive polysaccharide capsule that is resistant to neutrophil phagocytosis and complement opsonization. 

Dunn, P. A. and Tyrer, H. W. (1981) Quantitation of neutrophil phagocytosis, using fluorescent latex beads. Correlation of microscopy and flow cytometry. J. Lab. Clin. Med. 98, 374-381. 

Trinkle, L. S., Wellhausen, S. R., andMcLeish, K. R. (1987) A simultaneous flow cytometric measurement of neutrophil phagocytosis and oxidative burst in whole blood. Diagnostic and Clin. Immunol. 5, 62-68. 

Several studies have demonstrated that MDMA can suppress neutrophil phagocytosis as well as suppress the production of tumor necrosis factor-alpha and interleukin. 

In our hands, we have observed that IL-2 was not able to induce neutrophil phagocytosis of opsonized sheep red blood cells in vitro [49]. MacDonald et al. 

To date, no data are available in the literature concerning the role of IL-21 on neutrophil cell physiology. Our preliminary results indicate that this cytokine does not modulate human neutrophil phagocytosis and apoptosis [Pelletier et al., unpubl. data]. Other experiments need to be performed to clearly establish whether or not IL-21 is a neutrophil agonist. Whether or not these cells express the IL-21 Ra chain remains to be determined. 

Key Words Macrophage neutrophil phagocytosis immunofluorescence microscopy antibody opsonin. 

Weineisen M, Sjobring U, Fallman M et al. Streptococcal M5 protein prevents neutrophil phagocytosis by interfering with CDllb/CD18 receptor-mediated association and signaling. J Immunol 2004 172(6) 3798-3807. 

The capability of Echinacin to stimulate neutrophil phagocytosis in vivo has been demonstrated in two volunteer studies. In the first open study, in 12 healthy males, Echinacin administered i.m. on 4 consecutive days significantly increased by 20-30% the ability of neutrophils to phagocytose Candida albicans ex vivo [19]. In a second double-blind study on 24 male volunteers, Echinacin Liquidum was administered orally (30 drops, three times a day) for five days to 12 subjects, the other 12 received placebo [20]. By the fifth day of treatment, the phagocytic activity of isolated neutrophils was significantly higher (+ 120%) in the Echinacin group in comparison to placebo. 

Effects of ascorbic acid and calcium and sodium ascorbate on neutrophil phagocytosis and post-phagocytic metabolic activity. South African Med. J. 56 401-404. 

Herant, M., Heinrich, V. and Dembo, M. (2005) Mechanics of neutrophil phagocytosis behavior of the cortical tension. Journal of Cell Science, 118, 1789-97. 

Moore S.I., G.B. Hufihagle, G.H. Chen, E.S. White and P. Mancuso, 2003. Leptin modulates neutrophil phagocytosis of Klehsiella pneumoniae. Infect. Immun. 71,4182-4185. 

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