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

Area of Science:

• Ophthalmology
• Microbiology
• Genetics

Background:

• Acanthamoeba keratitis (AK) is an emerging concern, often linked to contact lens wear.
• Genotypic identification of Acanthamoeba isolates is crucial for understanding virulence and disease progression.
• This study marks the first genotypic identification of clinical Acanthamoeba isolates from keratitis in Malaysia.

Purpose of the Study:

• To perform genotypic identification of clinical Acanthamoeba isolates from Malaysian keratitis patients.
• To investigate the correlation between mRNA expression of specific virulent markers (MBP and AhLBP) and Acanthamoeba cytopathogenicity.

Main Methods:

• Ten clinical Acanthamoeba isolates were obtained from corneal scrapings.
• 18S rRNA gene sequencing was used for genotypic identification and intra-genotypic variation analysis.
• mRNA expression levels of MBP and AhLBP were measured and correlated with cytopathogenicity.

Main Results:

• All ten Malaysian isolates belonged to the T4 genotype, a common genotype associated with AK.
• Specific subtypes within T4, including T4/6, T4/2, T4/16, and a novel T4/36, were identified.
• A direct correlation was observed between MBP and AhLBP mRNA expression and the cytopathic effect of Acanthamoeba on rabbit corneal fibroblasts.

Conclusions:

• The predominant T4 genotype identified in Malaysian clinical isolates aligns with global findings for AK.
• Quantifying mRNA expression of Acanthamoeba virulent markers offers a valuable approach to understanding AK pathogenesis.