Functional roles of mannose-binding protein in the adhesion, cytotoxicity and phagocytosis of Acanthamoeba castellanii

Kim, Jong Hyun; Matin, Abdul; Shin, Hong-Jae; Park, Hyun; Yoo, Kyung Tae; Yuan, Xi Zhe; Kim, Kwang Sik; Jung, Suk Yul

doi:10.1016/j.exppara.2012.08.007

Cited by 29 publications

(20 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A priori , this observation suggests that Acanthamoeba would be an unlikely target for the anti‐predator activities of phage‐encoded exotoxins. However, the finding that, at least in the case of E. coli , bacterial uptake is mediated by a receptor (Kim et al ., ; J.W. Arnold, G.B.…”

Section: Discussionmentioning

confidence: 99%

The Trojan Horse of the microbiological arms race: phage‐encoded toxins as a defence against eukaryotic predators

Arnold

Koudelka

2013

Environmental Microbiology

View full text Add to dashboard Cite

Phage-encoded Shiga toxin (Stx) acts as a bacterial defence against the eukaryotic predator Tetrahymena. To function as an effective bacterial anti-predator defence, Stx must kill a broad spectrum of predators. Consistent with that assertion, we show here that bacterially encoded Stx efficiently kills the bacteriovore Acanthamoeba castellanii in co-culture. We also show that, in addition to Stx, the phage-encoded exotoxin, diphtheria toxin (Dtx) expressed by Corynebacterium diphtheriae also can function as part of an anti-predator strategy; it kills Acanthamoeba in co-culture. Interestingly, only exotoxins produced by bacteria internalized by the Acanthamoeba predator are cytolethal; the presence of purified Dtx or Stx in culture medium has no effect on predator viability. This finding is consistent with our results indicating that intoxication of Acanthamoeba by these exotoxins does not require a receptor. Thus bacteria, in the disguise of a food source, function as a 'Trojan Horse', carrying genes encoding an exotoxin into target organisms. This 'Trojan Horse' mechanism of exotoxin delivery into predator cells allows intoxication of predators that lack a cell surface receptor for the particular toxin, allowing bacteria-bearing exotoxins to kill a broader spectrum of predators, increasing the fitness of the otherwise 'defenceless' prey bacteria.

show abstract

Section: Discussionmentioning

confidence: 99%

The Trojan Horse of the microbiological arms race: phage‐encoded toxins as a defence against eukaryotic predators

Arnold

Koudelka

2013

Environmental Microbiology

View full text Add to dashboard Cite

show abstract

“…Acanthamoeba were capable of adhering and invading the extracellular matrix components such as laminin and collagen type I [ 32 ]. Previous studies provided information on the role of MBP and AhLBP as the marker of pathogenicity, mostly in protein level and a few in DNA works [ 31 , 33 – 36 ].…”

Section: Introductionmentioning

confidence: 99%

Acanthamoeba-mediated cytopathic effect correlates with MBP and AhLBP mRNA expression

Nordin

Ghafar

et al. 2017

Parasites Vectors

View full text Add to dashboard Cite

BackgroundIn recent years, the concern of Acanthamoeba keratitis has increased since the infection is often associated with contact lens use. Partial 18S rRNA genotypic identification of Acanthamoeba isolates is important to correlate with pathophysiological properties in order to evaluate the degree of virulence. This is the first report of genotypic identification for clinical isolates of Acanthamoeba from corneal scrapings of keratitis in Malaysia. This study is also the first to correlate the mRNA expression of MBP and AhLBP as virulent markers for axenic strains of Acanthamoeba.ResultsIn this study, ten clinical isolates were obtained from corneal scrapings. Rns genotype and intra-genotypic variation at the DF3 region of the isolates were identified. Results revealed that all clinical isolates belonged to the T4 genotype, with T4/6 (4 isolates), T4/2 (3 isolates), T4/16 (2 isolates) and one new genotype T4 sequence (T4/36), being determined. The axenic clinical isolates were cytopathogenic to rabbit corneal fibroblasts. MBP and AhLBP mRNA expression are directly correlated to Acanthamoeba cytopathic effect.ConclusionsAll ten Malaysian clinical isolates were identified as genotype T4 which is predominantly associated with AK. Measuring the mRNA expression of Acanthamoeba virulent markers could be useful in the understanding of the pathogenesis of Acanthamoeba keratitis.Electronic supplementary materialThe online version of this article (doi: 10.1186/s13071-017-2547-0) contains supplementary material, which is available to authorized users.

show abstract

“…Graft failure was defined as the irreversible loss of central graft clarity and the loss of visual acuity. For eyes in which the graft did not remain clear, the follow-up interval included the period from surgery to graft failure [ 8 , 9 ].…”

Section: Methodsmentioning

confidence: 99%

Associated factors, diagnosis and management of Acanthamoeba keratitis in a referral Center in Southern China

Zhong

Deng

et al. 2017

BMC Ophthalmol

View full text Add to dashboard Cite

BackgroundTo analyse the associated factors, diagnosis, clinical manifestations and therapeutic effects of Acanthamoeba keratitis at a tertiary ophthalmic centre in Southern China.MethodsA retrospective clinical study was performed in fifteen patients who were admitted to Zhongshan Ophthalmic Centre (ZOC) from January 2004 to December 2014. The patients’ pathogenesis-associated factors were analysed, and preoperative diagnoses were determined using corneal scraping cultures and/or confocal microscopy followed. All diagnoses were confirmed by postoperative pathological examinations. At follow-up, best-corrected visual acuity (BCVA), the recurrence rate and graft transparency were evaluated to assess therapeutic effects.ResultsThe main pathogenic factors observed in the fifteen patients were a history of injury or a foreign body entering the eyes (12 cases). In all, Acanthamoeba keratitis was preoperatively diagnosed in 5 cases using corneal scraping cultures or confocal microscopy. Ocular symptoms included redness, photophobia, tearing, and blurred vision. Penetrating keratoplasty was performed in thirteen patients, and postoperative pathological examinations were performed to confirm these diagnoses. The logarithm of the minimum angle of resolution (logMAR) of visual acuity was significantly improved after keratoplasty (p < 0.01). No recurrence was observed, and approximately 90% of the corneal grafts were found to be transparent during the follow-up period.ConclusionsCorneal trauma may be the main pathogenic factor that causes Acanthamoeba keratitis in southern China. Corneal scraping combined with confocal microscopy was helpful for achieving a correct diagnosis. Early keratoplasty combined with amoebicidal therapy is an effective treatment strategy in Acanthamoeba keratitis.

show abstract

Functional roles of mannose-binding protein in the adhesion, cytotoxicity and phagocytosis of Acanthamoeba castellanii

Cited by 29 publications

References 15 publications

The Trojan Horse of the microbiological arms race: phage‐encoded toxins as a defence against eukaryotic predators

The Trojan Horse of the microbiological arms race: phage‐encoded toxins as a defence against eukaryotic predators

Acanthamoeba-mediated cytopathic effect correlates with MBP and AhLBP mRNA expression

Associated factors, diagnosis and management of Acanthamoeba keratitis in a referral Center in Southern China

Contact Info

Product

Resources

About