Role of Tear Anti-Acanthamoeba IgA in Acanthamoeba Keratitis

Author(s):  
J. Y. Niederkorn ◽  
H. Alizadeh ◽  
H. Leher ◽  
S. Apte ◽  
S. El Agha ◽  
...  
Pathogens ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 321 ◽  
Author(s):  
Steven Rolland ◽  
Luce Mengue ◽  
Cyril Noël ◽  
Stéphanie Crapart ◽  
Anne Mercier ◽  
...  

Acanthamoeba castellanii is a ubiquitous free-living amoeba. Pathogenic strains are causative agents of Acanthamoeba keratitis and granulomatous amoebic encephalitis. In response to adverse conditions, A. castellanii differentiate into cysts, which are metabolically inactive and resistant cells. This process, also named encystment, involves biochemical and genetic modifications that remain largely unknown. This study characterizes the role of the ACA1_384820 Acanthamoeba gene during encystment. This gene encodes a putative N-acetyltransferase, belonging to the Gcn5-related N-acetyltransferase (GNAT) family. We showed that expression of the ACA1_384820 gene was down-regulated as early as two hours after induction of encystment in A. castellanii. Interestingly, overexpression of the ACA1_384820 gene affects formation of cysts. Unexpectedly, the search of homologs of ACA1_384820 in the Eukaryota gene datasets failed, except for some species in the Acanthamoeba genus. Bioinformatics analysis suggested a possible lateral acquisition of this gene from prokaryotic cells. This study enabled us to describe a new Acanthamoeba gene that is down-regulated during encystment.


2015 ◽  
Vol 114 (9) ◽  
pp. 3283-3289 ◽  
Author(s):  
Ismail Soner Koltas ◽  
Fadime Eroglu ◽  
Elif Erdem ◽  
Meltem Yagmur ◽  
Ferdi Tanır

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
M. Barbariga ◽  
F. Vallone ◽  
E. Mosca ◽  
F. Bignami ◽  
C. Magagnotti ◽  
...  

Abstract Corneal neo-vascularization (CNV) is a highly prevalent medical condition which impairs visual acuity. The role of specific proteins in modulating CNV has been extensively reported, although no studies have described the entire human proteome in CNV corneas. In this paper, we performed a proteomic analysis of vascularized vs healthy corneal stroma, in a CNV mouse model and in CNV-affected patients, with a specific focus on extracellular matrix (ECM) proteins. We identified and quantified 2315 murine proteins, 691 human proteins and validated 5 proteins which are differentially expressed in vascularized samples and conserved in mice and humans: tenascin-C and fibronectin-1 were upregulated, while decorin, lumican and collagen-VI were downregulated in CNV samples. Interestingly, among CNV patients, those affected with Acanthamoeba keratitis showed the highest levels of fibronectin-1 and tenascin-C, suggesting a specific role of these two proteins in Acanthamoeba driven corneal CNV. On a broader picture, our findings support the hypothesis that the corneal stroma in CNV samples is disorganized and less compact. We are confident that the dissection of the human corneal proteome may shed new light on the complex pathophysiology of human CNV, and finally lead to improved treatments.


Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 266
Author(s):  
Yu-Jen Wang ◽  
Sung-Chou Li ◽  
Wei-Chen Lin ◽  
Fu-Chin Huang

Acanthamoeba act as hosts for various microorganisms and pathogens, causing Acanthamoeba Keratitis (AK). To investigate the association between endosymbionts and AK progression, we performed a metagenomics study to characterize the intracellular microbiome from five lenses associated with AK isolates and standard strains to characterize the role of ocular flora in AK progression. The used clinical isolates were axenic cultured from lenses associated with AK patients. AK isolates and standard controls such as 16S ribosomal RNA sequencing techniques were used for analysis. The microbiome compositions and relative abundance values were compared. The orders of Clostridiales and Bacteroidales presented major populations of intracellular microbes belonging to all isolates. Comparison of the different source isolates showed that most of the abundance in keratitis isolates came from Ruminococcus gnavus (121.0 folds), Eubacterium dolichum (54.15 folds), Roseburia faecis (24.51 folds), and Blautia producta (3.15 folds). Further analysis of the relative abundance data from keratitis isolates showed that Blautia producta was positively correlated with the disease course. In contrast, Bacteroides ovatus was found to be abundant in early-stage keratitis isolates. This study reveals the abundant anaerobic Gram-positive rods present in severe keratitis isolate and characterize the association between Acanthamoeba and ocular flora in AK progression.


Cornea ◽  
1997 ◽  
Vol 16 (3) ◽  
pp. 277???283 ◽  
Author(s):  
David H. Park ◽  
David A. Palay ◽  
Sheraz M. Daya ◽  
R. Doyle Stulting ◽  
Jay H. Krachmer ◽  
...  

Ophthalmology ◽  
2011 ◽  
Vol 118 (1) ◽  
pp. 29-35 ◽  
Author(s):  
Pravin K. Vaddavalli ◽  
Prashant Garg ◽  
Savitri Sharma ◽  
Virender S. Sangwan ◽  
Gullapalli N. Rao ◽  
...  

2007 ◽  
Vol 93 (5) ◽  
pp. 1114-1120 ◽  
Author(s):  
Hassan Alizadeh ◽  
Sudha Neelam ◽  
Jerry Y. Niederkorn

Cornea ◽  
2000 ◽  
Vol 19 (Supplement 2) ◽  
pp. S110
Author(s):  
J. Y. Niederkorn ◽  
H. Alizadeh ◽  
H. Leher ◽  
S. Apte ◽  
S. El Agha ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document