@article {715,
	title = {Lipid rafts, caveolae, caveolin-1, and entry by Chlamydiae into host cells.},
	journal = {Exp Cell Res},
	volume = {287},
	year = {2003},
	month = {2003 Jul 1},
	pages = {67-78},
	abstract = {Obligate intracellular bacterial pathogens of the genus Chlamydia are reported to enter host cells by both clathrin-dependent and clathrin-independent processes. C. trachomatis serovar K recently was shown to enter cells via caveolae-like lipid raft domains. We asked here how widespread raft-mediated entry might be among the Chlamydia. We show that C. pneumoniae, an important cause of respiratory infections in humans that additionally is associated with cardiovascular disease, and C. psittaci, an important pathogen in domestic mammals and birds that also infects humans, each enter host cells via cholesterol-rich lipid raft microdomains. Further, we show that C. trachomatis serovars E and F also use these domains to enter host cells. The involvement of these membrane domains in the entry of these organisms was indicated by the sensitivity of their entry to the raft-disrupting agents Nystatin and filipin, and by their intracellular association with caveolin-1, a 22-kDa protein associated with the formation of caveolae in rafts. In contrast, caveolin-marked lipid raft domains do not mediate entry of C. trachomatis serovars A, 36B, and C, nor of LGV serovar L2 and MoPn. Finally, we show that entry of each of these chlamydial strains is independent of cellular expression of caveolin-1. Thus, entry via the Nystatin and filipin-sensitive pathway is dependent on lipid rafts containing cholesterol, rather than invaginated caveolae per se.},
	keywords = {Anti-Bacterial Agents, Caveolae, Caveolin 1, Caveolins, Chlamydia, Chlamydia Infections, Cholesterol, Dose-Response Relationship, Drug, Eukaryotic Cells, Filipin, HeLa Cells, Host-Parasite Interactions, Humans, Membrane Microdomains, Nystatin, Species Specificity},
	issn = {0014-4827},
	author = {Stuart, Elizabeth S and Webley, Wilmore C and Norkin, Leonard C}
}
@article {712,
	title = {Association of caveolin with Chlamydia trachomatis inclusions at early and late stages of infection.},
	journal = {Exp Cell Res},
	volume = {266},
	year = {2001},
	month = {2001 Jun 10},
	pages = {229-38},
	abstract = {The mechanism by which the intracellular bacterial pathogen Chlamydia trachomatis enters eukaryotic cells is poorly understood. There are conflicting reports of entry occurring by clathrin-dependent and clathrin-independent processes. We report here that C. trachomatis serovar K enters HEp-2 and HeLa 229 epithelial cells and J-774A.1 mouse macrophage/monocyte cells via caveolin-containing sphingolipid and cholesterol-enriched raft microdomains in the host cell plasma membranes. First, filipin and nystatin, drugs that specifically disrupt raft function by cholesterol chelation, each impaired entry of C. trachomatis serovar K. In control experiments, filipin did not impair entry of the same organism by an antibody-mediated opsonic process, nor did it impair entry of BSA-coated microspheres. Second, the chlamydia-containing endocytic vesicles specifically reacted with antisera against the caveolae marker protein caveolin. These vesicles are known to become the inclusions in which parasite replication occurs. They avoid fusion with lysosomes and instead traffic to the Golgi region, where they intercept Golgi-derived vesicles that recycle sphingolipids and cholesterol to the plasma membrane. We also report that late-stage C. trachomatis inclusions continue to display high levels of caveolin, which they likely acquire from the exocytic Golgi vesicles. We suggest that the atypical raft-mediated entry process may have important consequences for the host-pathogen interaction well after entry has occurred. These consequences include enabling the chlamydial vesicle to avoid acidification and fusion with lysosomes, to traffic to the Golgi region, and to intercept sphingolipid-containing vesicles from the Golgi.},
	keywords = {Animals, Caveolin 1, Caveolins, Cell Line, Chlamydia trachomatis, Epithelium, Filipin, HeLa Cells, Humans, Inclusion Bodies, Macrophages, Membrane Microdomains, Mice, Nystatin, Phagosomes},
	issn = {0014-4827},
	doi = {10.1006/excr.2001.5202},
	author = {Norkin, L C and Wolfrom, S A and Stuart, E S}
}
