This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Herrmann, J. M.
Right arrow Articles by Simons, E. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Herrmann, J. M.
Right arrow Articles by Simons, E. R.

 Previous Article  |  Next Article 

Infection and Immunity, August 2007, p. 3989-3998, Vol. 75, No. 8
0019-9567/07/$08.00+0     doi:10.1128/IAI.00388-07
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Sequential Chemotactic and Phagocytic Activation of Human Polymorphonuclear Neutrophils{triangledown}

Jens Martin Herrmann,1,2 John Bernardo,2 Heidi J. Long,2 Kurt Seetoo,2 Mary E. McMenamin,2 Eraldo L. Batista Jr.,1 Thomas E. Van Dyke,1 and Elizabeth R. Simons2*

Department of Oral Biology and Periodontology, Goldman School of Dental Medicine,1 Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 021182

Received 14 March 2007/ Returned for modification 27 April 2007/ Accepted 17 May 2007

Human polymorphonuclear neutrophils (PMN) chemotax to a foreign entity. When the chemoattractants’ origins are reached, specific receptors bind to the invader's surface, initiating phagocytosis, phagosome formation, and fusion with granule membranes, generating the bactericidal oxidative burst, and releasing lytic enzymes, specific peptides, and proteins. We explored the initial signaling involved in these functions by observing naïve, unprimed PMN in suspension using fluorescent indicators of cytoplasmic signals ({Delta}[Ca2+]i and {Delta}pHi) and of bactericidal entities (oxidative species and elastase) exposed to N-formyl-methionyl-leucyl-phenylalanine (fMLP) and/or multivalent immune complexes (IC). fMLP and IC each initiate a rapid transient rise in [Ca2+]i, mostly from intracellular stores, simultaneously with a drop in pHi; these are followed by a drop in [Ca2+]i and a rise in pHi, with the latter being due to a Na+/H+ antiport. The impact of a second stimulation depends on the order in which stimuli are applied, on their dose, and on their nature. Provided that [Ca2+]i is restored, 10–7 M fMLP, previously shown to elicit maximal {Delta}[Ca2+]i but no bactericidal functions, did not prevent the cells’ responses with {Delta}[Ca2+]i to a subsequent high dose of fMLP or IC; conversely, cells first exposed to 120 µg/ml IC, previously shown to elicit maximal {Delta}[Ca2+]i and bactericidal functions, exhibited no subsequent {Delta}[Ca2+]i or {Delta}pHi to either stimulus. While exposure to 10–7 M fMLP, which saturates the PMN high-affinity receptor, did not elicit bactericidal release from these naïve unprimed PMN in suspension, 10–5 M fMLP did, presumably via the low-affinity receptor, using a different Ca2+ source.

* Corresponding author. Mailing address: Department of Biochemistry, K-602, Boston University School of Medicine, 80 East Concord St., Boston, MA 02118. Phone: (617) 638-4332. Fax: (617) 638-5339. E-mail: esimons{at}bu.edu

{triangledown} Published ahead of print on 25 May 2007.

Editor: J. B. Bliska

Infection and Immunity, August 2007, p. 3989-3998, Vol. 75, No. 8
0019-9567/07/$08.00+0     doi:10.1128/IAI.00388-07
Copyright © 2007, American Society for Microbiology. All Rights Reserved.





Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»