IAI FigSearch
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
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 arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Ketterer, M. R.
Right arrow Articles by Apicella, M. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Ketterer, M. R.
Right arrow Articles by Apicella, M. A.

Infection and Immunity, August 1999, p. 4161-4170, Vol. 67, No. 8
0019-9567/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.

Infection of Primary Human Bronchial Epithelial Cells by Haemophilus influenzae: Macropinocytosis as a Mechanism of Airway Epithelial Cell Entry

Margaret R. Ketterer,1 Jian Q. Shao,1 Douglas B. Hornick,2 Ben Buscher,1 Venkata K. Bandi,3 and Michael A. Apicella1,*

Department of Microbiology1 and Department of Medicine,2 The University of Iowa, Iowa City, Iowa, and Department of Medicine, Baylor College of Medicine, Houston, Texas3

Received 14 January 1999/Returned for modification 21 March 1999/Accepted 14 May 1999

Nontypeable Haemophilus influenzae is an exclusive human pathogen which infects the respiratory epithelium. We have initiated studies to explore the interaction of the nontypeable H. influenzae strain 2019 with primary human airway epithelial cells by electron and confocal microscopy. Primary human airway cell cultures were established as monolayers on glass collagen-coated coverslips or on semipermeable membranes at an air-fluid interface. Scanning electron microscopy indicated that bacteria adhered to nonciliated cells in the population. The surface of infected cells showed evidence of cytoskeletal rearrangements manifested by microvilli and lamellipodia extending toward and engaging bacteria. Confocal microscopic analysis demonstrated that infection induced actin polymerization with an increase in cortical actin as well as evidence of actin strands around the bacteria. Transmission electron microscopic analysis showed lamellipodia and microvilli surrounding organisms, as well as organisms adherent to the cell surface. These studies also demonstrated the presence of bacteria within vacuoles inside of airway cells. Confocal microscopic studies with Texas red-labeled dextran (molecular weight, 70,000) indicated that H. influenzae cells were entering cells by the process of macropinocytosis. These studies indicate that nontypeable H. influenzae can initiate cytoskeletal rearrangement within human airway epithelium, resulting in internalization of the bacteria within nonciliated human airway epithelial cells by the process of macropinocytosis.


* Corresponding author. Mailing address: Department of Microbiology, The University of Iowa, 51 Newton Rd., Iowa City, IA 52242. Phone: (319) 335-7807. Fax: (319) 335-9006. E-mail: michael-apicella{at}uiowa.edu.


Infection and Immunity, August 1999, p. 4161-4170, Vol. 67, No. 8
0019-9567/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.



This article has been cited by other articles:




Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. J. Virol. Eukaryot. Cell
Microbiol. Mol. Biol. Rev. Clin. Vaccine Immunol. All ASM Journals

Copyright © 1999 by the American Society for Microbiology. All rights reserved.